jhuccs1.us€¦ · Web viewCAMPCS/3 Protocol1. Objective and specific aims. 2.1. Background for...

CAMP Continuation Study/Phase 3 (CAMPCS/3) Protocol

Abstract............................................................................................................3

1. Objective and specific aims.........................................................................41.1. Objective...........................................................................................41.2. Specific aims.....................................................................................4

2. Background.................................................................................................62.1. Background for Specific Aim 1, Hypothesis 1....................................62.2. Background for Specific Aim 1, Hypothesis 2....................................72.3. Background for Specific Aim 2, Hypothesis 3....................................82.4. Background for Specific Aim 3, Hypothesis 4....................................82.5. Background for Specific Aim 4, Hypothesis 5....................................92.6. Rationale.........................................................................................10

3. Preliminary data........................................................................................113.2. Preliminary data from CAMP, CAMPCS, and CAMPCS/2...................12

3.2.1. Ages of participants..............................................................123.2.2. Determination of lung function and airway responsiveness

(Specific Aims 1-4)................................................................123.2.3. Determination of inflammatory-related phenotypes (Specific

Aims 1, 3, and 4)..................................................................123.2.4. Personal smoking in CAMP participants (Specific Aim 1)......133.2.5. Asthma symptoms/morbidity and medication use (Specific

Aim 1)...................................................................................133.2.6. Environmental measures......................................................133.2.7. Patterns of growth and decline of lung function (Specific Aim

4, Hypothesis 5)....................................................................143.2.8. Somatic Growth (Specific Aim 3)..........................................143.2.9. Preliminary data on genetic polymorphisms and lung function

(Specific Aims 2 and 4).........................................................14

4. Methods....................................................................................................164.1. Overview of CAMPCS/3...................................................................164.2. Consent and recruitment in CAMPCS/3...........................................174.3. Patient contact schedule and content of visits...............................174.4. Measurement and assessment methods.........................................18

4.4.1. Pre- and post-BD FEV1 and FEV1/FVC ratio............................184.4.2. Airway responsiveness.........................................................18

CAMPCS/CAMPCS3 Ntbs/Proto_CS3\Manall_610:55am Wednesday, April 27, 2011/rmjals

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4.4.3. Somatic growth....................................................................194.4.4. Symptoms/morbidity and medication use............................194.4.5. Environmental measures......................................................204.4.6. Atopy related phenotypes....................................................204.4.7. ....................................................................Pregnancy history

.............................................................................................204.5. Patient retention.............................................................................204.6. Data management for clinical data.................................................214.7. Data management for genetic studies............................................22

4.7.1. Bioinformatics management system (ORAGEN)...................224.7.2. Management of genotypic data............................................224.7.3. Management of phenotype data...........................................22

4.8. Quality assurance...........................................................................224.9. Data monitoring..............................................................................234.10. Human subjects..............................................................................24

4.10.1.....................Characteristics of the proposed study population.............................................................................................24

4.10.2. ..................................................Sources of research material.............................................................................................24

4.10.3. .................................................Protection of human subjects.............................................................................................24

4.11. Data analysis..................................................................................254.11.1. ...................................................................General approach

.............................................................................................254.11.2. .........................................Measurement of steroid treatment

.............................................................................................264.11.3. ..............................Analyses for Specific Aim 1, Hypothesis 1




.............................................................................................284.11.7. ...............................Analysis for Specific Aim 4, Hypothesis 5

.............................................................................................294.11.8. ........................Sample size considerations - all Specific Aims

.............................................................................................294.11.9. . .Statistical power for multistage whole genome association

analysis, Specific Aim 2, Hypothesis 3..................................304.12. Study organization..........................................................................314.13. Use of comparison populations to describe abnormal patterns of

growth and decline of lung function (Specific Aims 4, Hypothesis 5)........................................................................................................31


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4.14. Methods for defining patterns of reduced lung function growth and early decline of lung function..........................................................32

5. Appendices................................................................................................345.1. Design summary.............................................................................355.2. Data collection schedule.................................................................37

Literature cited....................................................................................................38


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CAMPCS/3 Protocol Contents


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CAMPCS/3 Protocol Abstract

Abstract

This protocol is for the CAMP Continuation Study/Phase 3 (CAMPCS/3), a 4-year observational followup study of the participants in the Childhood Asthma Management Program (CAMP) trial.

The CAMP trial was a multicenter randomized clinical trial designed to determine the effects of three treatments (albuterol alone, albuterol with inhaled corticosteroid (ICS), albuterol with inhaled non-steroid) in1041 children (ages 5-12 at initial screening) with mild to moderate asthma on pulmonary function during a 3.5-5.5 year treatment phase. The cohort has been followed since the end of the CAMP trial, first in the CAMP Continuation Study (CAMPCS) which lasted 4.5 years and subsequently in the CAMP Continuation Study/Phase 2 (CAMPCS/2) which lasted 4 years and had the purpose of determining the long term effects of the treatments on lung and somatic growth. CAMPCS/3 is designed to follow the cohort for 4 additional years to study the determinants of lung growth and progression of obstruction due to persistent childhood asthma.

Childhood asthma can result in significant lung disease in adulthood and possibly the development of chronic obstructive pulmonary disease. None of the long-term followup studies of childhood asthma have had the close followup needed to define determinants of outcomes in young adulthood.

CAMPCS/3 has four specific aims: (1) Define the risk factors for reduced maximal attained lung function and/or progression of obstruction in young adults with mild to moderate persistent childhood asthma; (2) Identify genetic polymorphisms for reduced maximal attained lung function and progression of obstruction in young adults with mild to moderate persistent childhood asthma; (3) Determine effects into early adulthood of 4-6 years of prior continuous treatment with inhaled anti-inflammatory medications; and (4) Define patterns of reduced lung function growth and early decline of lung function in young adults with mild to moderate asthma.

Data collection procedures will be similar to those used in CAMP, CAMPCS, and CAMPCS2. Patients will have a total of 4 visits for spirometry (approximately 1 per year) and a fifth visit for methacholine challenge which may be scheduled at anytime in the latter half of year 1 through year 4. Procedures completed at


Abstract

CAMPCS/3 Protocol Abstract

the spirometry visits will include spirometry pre- and post-bronchodilator, height and weight measurement, and interim history interview (information on asthma symptoms, tobacco smoke exposure, medication use, and home environment will be collected).

The methacholine challenge visit will include methacholine challenge, height and weight measurement, and the same interim health history interview collected at the spirometry visits.


Abstract

CAMPCS/3 Protocol 1. Objective and specific aims

Objective and specific aims

Objective

CAMPCS/3 is an observational followup study of the children who participated in the Childhood Asthma Management Program (CAMP) trial. CAMPCS/3 will extend the CAMP Continuation Study/Phase 2 (CAMPCS/2) for 4 years and will thus continue the follow-up of the CAMP cohort through a total of 16-18 years by the end of the planned extension.

The objective of CAMPCS/3 is to complete our studies of the determinants of lung growth and progression of obstruction due to persistent childhood asthma. Several authors have commented on deviations from normal patterns of change in pulmonary function with age that foreshadow evolution of asthma into chronic airflow obstruction in adulthood (3, 7-9). Published data from the CAMP cohort have provided detailed information about effects of persistent asthma on lung growth through adolescence (10), and there are several studies of effects of asthma on decline in lung function in older adults (11-13). However, there are no comprehensive data on lung growth and the progression of obstruction due to asthma during young adulthood. CAMPCS/3 will determine clinical characteristics, early changes in pulmonary function, inflammatory markers, and genetic polymorphisms that put individual patients who had mild to moderate persistent childhood asthma at risk for progression towards chronic airflow obstruction. CAMP is the largest, most comprehensively phenotyped, genotyped, and best followed group of mild to moderate, persistent childhood asthmatics in the modern era. CAMPCS/3 represents the only opportunity to definitively determine the effects of persistent childhood asthma on lung function growth and decline in early adult life, and to define subgroups of patients with persistent asthma who are at increased risk for development of chronic airflow obstruction.

Specific aims

Specific Aim 1: Define risk factors for reduced maximal attained lung function and/or progression of obstruction in young adults with mild to moderate persistent childhood asthma.


Specific


Hypothesis 1: Increased airway lability (responsiveness to methacholine, reactivity to bronchodilator), increased inflammatory markers (allergy skin tests, serum IgE level, peripheral blood eosinophilia), and cigarette smoking (personal and passive) are related to the reduced maximal attained lung function (FEV1, FVC), and progression of obstruction (FEV1/FVC).

Hypothesis 2: (a) The presence of symptoms independently predicts reduced maximal attained lung function (FEV1, FVC) and progression of obstruction (FEV1/FVC), and (b) the likelihood of persistence of symptomatic asthma is predicted by increased airway lability, increased inflammation (allergy skin tests, serum IgE level, peripheral blood eosinophilia), and cigarette smoking (personal and passive).

Specific Aim 2: Identify genetic polymorphisms for reduced maximal attained lung function and progression of obstruction in young adults with mild to moderate persistent childhood asthma.

Hypothesis 3: Maximally attained lung function (FEV1, FVC), and progression of obstruction (FEV1/FVC) will be associated with one or more specific Single Nucleotide Polymorphisms (SNPs) from 550,000 whole genome tagging SNPs genotyped in the 400 Caucasian parent-child trios in the CAMP cohort.

Specific Aim 3: Determine effects into early adulthood of 4-6 years of prior continuous treatment with inhaled anti-inflammatory medications.

Hypothesis 4: Early continuous treatment lasting 4-6 years of patients with mild to moderate childhood asthma with inhaled corticosteroids (ICS) compared to treatment with placebo (a) will not influence maximally attained lung function (FEV1, FVC), progression of obstruction (FEV1/FVC), and increased airway lability in young adulthood; and (b) will have a small (<1cm) effect on attained maximal height, controlling both (a) and (b) for age, gender, ethnicity, and asthma duration and severity at baseline.

Specific Aim 4: Define patterns of reduced lung function growth and early decline of lung function in young adults with mild to moderate persistent childhood asthma compared to normal subjects, controlling for age, height, and gender.


Specific


Hypothesis 5: (a) Four consistent patterns of FEV1 growth and decline can be identified from comparisons of CAMP persistent asthmatics to non-asthmatics from both longitudinal (Vlagtwedde/Vlaardingen and CARDIA) and cross-sectional (NHANES III) studies: 1) Normal lung growth and no decline, 2) Reduced lung growth, 3) Normal lung growth then early decline, and 4) Reduced lung growth and early decline; and (b) These four patterns can be discriminated from one another using clinical characteristics, early changes in pulmonary function, inflammatory markers, and genetic polymorphisms.


Specific

CAMPCS/3 Protocol 2. Background

Background

Background for Specific Aim 1, Hypothesis 1

Importance of longitudinal follow-up of patients with persistent asthma: Deficits in growth of lung function in childhood due to asthma are important to fully define, as asthma is an important determinant of lung function (FEV1) in adults, independent of smoking (12). Individuals with asthma are at risk for significant lung disease due to more rapid decline in lung function during adulthood than non-asthmatics (11, 13). Longitudinal studies examining the effect of asthma or wheeze on lung function growth from the early school years to adolescence provide conflicting findings (14-23), with some reporting that abnormalities observed at ages 5-7 years did not increase during follow-up into adolescence or early adulthood (14, 20-22, 24, 25), and with others finding decreasing lung function during adolescence (16, 26). Discrepancies in findings of effects of asthma on long-term lung function growth and decline are due in part to use of asthmatics nested within birth cohorts (21, 22) or selected from school populations (27), most of whom have mild disease.

Factors identified as responsible for evolution of abnormalities in lung function: Airway responsiveness and a low level of lung function are independent risk factors for a low level of FEV1 in early adulthood, in both individuals with asthma (28) and individuals without diagnosed asthma (4, 29, 30). A variety of other epidemiologic sources have confirmed that asymptomatic hyper responsiveness is associated with accelerated decline in FEV1 in early adult life and is a risk factor for the development of COPD and for mortality. Ongoing respiratory symptoms are also related to decreases in lung function (17, 18, 31). However, children with asthma who become asymptomatic during adolescence continue to have spirometric abnormalities and airway responsiveness to methacholine or cold air challenge (32-36), significant airway inflammation and airway remodeling on bronchial biopsy (37), and eosinophils in bronchoalveolar lavage fluid (38). The finding that abnormalities are present when symptoms have remitted presents a strong argument for collection and analysis of levels of lung function and airway responsiveness longitudinally in young adulthood.

Timing of decline from maximum values and factors that may be responsible


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for this abnormal pattern: In normal individuals, FEV1 reaches a maximal level in late adolescence or early adulthood and remains stable for several years before declining throughout the rest of life. These patterns of growth and decline of lung function are important determinants of lung function in later adulthood, and both low maximal levels and early decline are associated with development of chronic airway obstruction in later adult life (39, 40). Because of the relationship between the abnormalities in patterns of growth and decline of lung function and subsequent development of chronic airway obstruction, there has been increasing interest in factors that influence pulmonary function in children as they approach and reach adulthood, particularly in high-risk populations. Determinants of abnormalities in patterns of growth and decline of lung function are multifactorial and complex, and data obtained longitudinally to determine factors associated with timing of decline from maximal levels of lung function are sparse. The best studies are CARDIA (13) and Vlagtwedde/Vlaardingen (4, 30, 41). CARDIA studied risk factors for cardiac disease with measurements of FEV1 at 3 to 5 year intervals up to 10 years and collection of information about doctor diagnosis of asthma and cigarette smoking. Individuals were enrolled at ages 18 to 30. Maximal FEV1 levels were achieved starting at age 19 and lasted a shorter time in males (to 24 years) than females (to about 27-28 years). Maximal FEV1 was lower and deteriorated more rapidly in participants with asthma. Cigarette smoking was also a factor and particularly important among asthmatics. Dr. Weiss analyzed data from the Vlagtwedde/Vlaardingen study with very similar results (42).

Effects of smoking on lung function: Timing of active cigarette smoking with regard to lung function is critical in determining an effect. Children who smoke at the level of 1 cigarette per day between the ages of 10-16 can reduce their maximally attained level of FEV1 by 10% (43-45). Comparable figures for childhood asthmatics are not available. Active cigarette smoking by asthmatics in adolescence and early adulthood is associated with increased hospitalizations, emergency department visits, and respiratory symptoms; lower levels of lung function; and increased levels of airways responsiveness (43-45). The extent to which the combination of asthma and smoking can lead to early decline in FEV1 and, hence, the development of chronic airflow obstruction, is currently unknown.


The course of asthma is recognized to be quite variable over time, and long-term consequences of this disease differ for affected individuals. The adult


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outcomes resulting from childhood asthma can only be evaluated from large, longitudinal, well-retained cohorts who are followed from childhood into adulthood. Studies of remission of asthma and subsequent relapse are highly variable in nature and have focused on small numbers of individuals with mild disease. Most studies have employed questionnaires sent to patients, with estimates of asthma obtained by report of symptoms in the past 12 months. Some of the studies examined patients at the time of follow-up; however, even these studies used self-report of symptoms in the past 12 months or 3 years to obtain information about the status of asthma. It is possible to make some estimates of the percentages of children who improve and those who remain with symptoms as they grow into adulthood; however, no long-term study of childhood asthma has included a comprehensive, longitudinal evaluation of risk factors for persistence of symptoms, abnormalities in pulmonary function in the absence of symptoms, and relapse of symptoms after periods of remission. No long-term follow-up study has included an evaluation of the role of environmental exposures on outcome, either in absolute terms or relative to specific sensitivities. Furthermore, whether prior asthma controller therapy should be considered as a modifying factor or as an independent marker of symptom persistence has also not been determined in previous studies.


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Allergic asthma in childhood, as seen in the mild-to-moderate subjects enrolled in CAMP, is clearly a heritable disease. The lambda S, or recurrence risk to relatives (a measure of heritability), for allergic asthma is thought to vary between 3 and 5 (46). When one considers twin studies, the proportion of phenotypic variants attributed to genetic factors ranges from 36-79% (47). The significant heritability estimates have been demonstrated for all of the allergic and inflammatory intermediate phenotypes for this condition (48, 49). There are now a total of 13 studies demonstrating linkages of an asthma phenotype to more than 34 chromosomal regions of the human genome (50-55). At least eight of these regions are highly replicable and have occurred in many studies (50-55). Four of these linked regions have been fine mapped using LD mapping and specific candidate genes identified (G protein-coupled receptor for asthma susceptibility [GPR154]) on chromosome 7p, chromosomes 13q14 (PDH finger protein 11 [PHF11]), 2q14 (dipeptidylpeptidase 10 [DPP10]), and 20p13 (disintegrin and metalloprotease 33 [ADAM 33]). Although there are more than 500 genetic association studies for asthma, most suffer from methodological problems. Given strict criteria with regard to replication, most of these studies do not replicate. To date, there have been reports of positive associations between variants in over 70 genes and asthma phenotypes (56). Of these, 30 associations were replicated in at least two populations and 9 associations were replicated in at least five populations, but the number of candidate genes that are linked to lung function level is very small. To date, no whole genome association study in asthma has been reported. Whole genome association studies offer a unique opportunity to assess association at a whole genome level rather than focus on individual genes. We have an opportunity in CAMP to relate 550,000 SNPs to the unique longitudinal lung function phenotypes being collected as part of this continuation study because of newly funded P01-HL083069 (ST Weiss PI) that includes funds for a whole genome association study of the 400 Caucasian trios in CAMP with a strong replication strategy. No whole genome study has been done for asthma or its lung function phenotypes, and CAMP provides the best longitudinal phenotype data on lung function in asthma in the world.


Numerous short-term studies of ICS therapy (up to 1 year) have reported improvements in measures of spirometry. Prior to CAMP, there had been no controlled study to examine longer term effects. In CAMP, children treated


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continuously with ICS (budesonide) demonstrated a rise in FEV1 compared to children in the placebo group over the first 6-12 months of the trial (57). But by completion of the 4-6 years of continuous treatment, the initial increase in the ICS-treated patients had waned, and the ICS and placebo groups did not differ in terms of FEV1 (57). The lack of long-term effect of ICS on post bronchodilator FEV1 was surprising.

In contrast to the transient-only benefit on post-bronchodilator FEV1, ICS treatment in CAMP resulted in significant and continued improvement in airway responsiveness and bronchodilator reactivity throughout the 4-6 year treatment interval (57). All previous studies demonstrating that ICS improved airway lability were short in duration (up to 1 year). In these short-term studies, the extent of improvement varied considerably among patients (58-60). Factors predictive of improvement in lability with ICS have been largely unknown.

While there have been many studies of ICS on somatic growth, most have been short-term (up to 1 year). Most articles published from the early 1980s did not find any effect of ICS on growth (61-66), but 4 reports in the 1990s did find a decrease in growth from beclomethasone given for periods up to 1 year (67-70). Two long-term follow-up studies without placebo control demonstrated that neither the duration of treatment nor cumulative dose of ICS influenced final height (71) (72). CAMP was the first long-term placebo-controlled study with 3.3-5.5 years of continuous treatment demonstrating a decrease in growth in the ICS-treated group, with an effect in the first year similar to that found in previous short-term studies, but also at the end of the 4-6 year treatment interval (decrease of 1.1 cm, P=0.005). These results were less concerning because of the observation that growth velocity was reduced primarily in the first year of the study, suggesting that height might catch up even with continued use of the drug. However, height in the previously ICS-treated CAMP patients remains lower than in the placebo group more than 4 years after discontinuation of the CAMP study treatment.


While it is not feasible to identify a concurrent cohort of otherwise similar normal subjects for longitudinal comparison to the CAMP cohort, there are three populations with non-asthmatic subsets of subjects that can be separately compared with the mild-to-moderate asthmatics in CAMP to define consistent abnormal patterns of growth and decline of lung function within the 20-30 year old age range of CAMPCS/3: Vlagtwedde/Vlaardingen (4, 30, 41, 42), NHANES III


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(73), and CARDIA (13). Sensitivity analyses using three relevant and generalizable control groups will define the range of effects of persistent asthma on abnormal patterns of growth and decline in lung function.


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Rationale

As shown in the accompanying figure, there are several patterns by which individuals acquire fixed airflow obstruction as adults: (1) reduced lung function growth, (2) early decline, or (3) rapid decline, or (4) some combination of (1), (2), and (3). No study has addressed the impact of persistent asthma on abnormalities in lung growth and decline in early adulthood or defined determinants of these abnormalities among persistent asthmatics. In fact, the information on the natural history of childhood asthma available in the literature is sparse. Although others have followed large cohorts of asthmatics, these studies are in the pre-ICS era, do not take into account treatment, and do not have the size or completeness of CAMP to assess the relevant questions; additionally, others have studied individuals contained within birth cohorts with wheeze or asthma diagnosis who had mild or intermittent disease and thus were unable to address issues that arise from more persistent disease. Information on genetics of asthma is expanding at an exponential rate. Linking the extensive genetic information available on CAMP individuals with the thorough phenotype information obtained over the 15-17 years of follow-up offers significant opportunity to understand more completely the role of candidate genes in this disease. The effects of CAMP treatment on asthma outcomes has already provided information to help practicing physicians with their uncertainties regarding the effect of long-term treatment on outcome of the disease (both symptoms and growth of the lung) and on somatic growth. Practicing physicians continue to need information that can come only from a longer-term follow-up of the CAMP cohort. The NAEPP Guidelines have provided a basis of treatment, but their authors acknowledged many areas in which evidence is lacking, including the continued questions and controversies regarding treatment in children due to the lack of long-term, prospective studies. The data obtained in CAMPCS/3 will provide answers to these questions and better evidence on which to base future recommendations, including long-term effects of early and continuous anti-inflammatory therapy and appropriate methods to track changes in


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pulmonary function to monitor asthma progression. The concept of careful tracking for patterns of changes over time when following patients with asthma is new, and could be a critical tool in assessing early signs of chronic airflow obstruction and for evaluating response to treatments designed to prevent or resolve asthma progression.


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CAMPCS/3 Protocol 3. Preliminary data

Preliminary data

CAMP phases

Study of the CAMP cohort has occurred in 3 phases: CAMP (trial), CAMPCS (observational study, 1st phase), and CAMPCS/2 (observational study, 2nd phase). During the CAMP trial, we studied 1041 children with mild to moderate persistent asthma in a clinical trial to determine if lung growth, as assessed by the change in FEV1, improved with regular use of inhaled anti-inflammatory agents over a 4-6 year period. CAMP children were aged 5-13 years at randomization (5-12 at initial screening) and from 8 clinics across the United States and Canada. 60% were male, and 32% were from minority populations. Median age at asthma onset was 2.5 years. 41% had at least one parent with a diagnosis of asthma, and 88% were atopic with at least one positive skin test. During a 28-day interval on bronchodilator only before randomization, there were, on average, 18 days with asthma symptoms or a peak flow <80% personal best. 30% of children were living in homes with a smoking parent and 70% reported having pets. These data document the representativeness of the CAMP sample and the relatively frequent environmental exposure and prevalence of atopy. The patients had completed an average of 4.3 years (range, 3.5-5.5) of follow-up as of the end of the trial. Only 5% of patients had missed more than 2 study visits in a row. Of the 1,371,018 diary days expected during the CAMP trial, 93% were returned and, of those returned, 88% had data. We reported in the New England Journal of Medicine in 2000 (57) that neither budesonide (an inhaled corticosteroid) nor nedocromil (an inhaled non-steroid) was better than placebo in terms of lung function, but inhaled budesonide improved airway responsiveness and provided better control of asthma than placebo or nedocromil. The side effects of budesonide were limited to a small, but significant reduction in growth that occurred during the first year of treatment without further effect.

The observational phase, known as the CAMP Continuation Study (CAMPCS), began in 1999. During the initial phase of observational followup, we successfully followed 90% of the children randomized in CAMP, with mean time of follow-up since randomization of 9.2 years as of the close of CAMPCS and missed visit rate of only 2%. In CAMPCS we focused on the effects of the initial


Prelimin


4-6 years of anti-inflammatory therapy on the rate of increase of maximal level of lung function, height, bone density, airway responsiveness, and occurrence, relapse, or remission of respiratory symptoms. 5,378 clinic visits and 5,100 telephone visits were completed in CAMPCS, with post-bronchodilator FEV1 obtained at 94% of spirometry visits, and FEV1PC20 obtained at 87% of methacholine visits. Quality grades for spirometry and methacholine challenges were as high as or higher in CAMPCS than in CAMP (3.9 for spirometry, 3.8 for methacholine, on a scale of 0-4). The missed visit rate in CAMPCS was 0.01 missed visits per 6 months of follow-up. 23 (2.5%) patients missed 1 or more in-person visits.

The 2nd phase of the observational followup (CAMPCS/2) began in May 2004. 879 (84%) of the original cohort of 1041 children participated in CAMPCS/2. 4029 in person visits and 4250 telephone visits were completed.

Preliminary data from CAMP, CAMPCS, and CAMPCS/2

Ages of participants

By the end of CAMPCS/2 in 2007, participants were age 17-26 years, and 62% of females and 59% of males were 21 years of age or older (Figure). By the end of the proposed CAMPCS/3 in 2012, all participants will be at least 20 years of age, with over 50% of the cohort at least 25 years old. This will allow analyses that will clearly answer many remaining questions on effects of asthma and its treatment on maximal growth of the lungs and assess the roles of other factors such as inflammatory markers (allergy skin test positivity, serum IgE level, and peripheral blood eosinophilia) and environmental exposure on lung and somatic growth.

Determination of lung function and airway responsiveness (Specific Aims 1-4)

In CAMP and CAMPCS, spirometry was done pre- and post-BD at least annually and pre-BD before methacholine annually. In CAMPCS/2, spirometry was done pre- and post-BD annually and an additional time (pre-BD) before


Prelimin


methacholine testing. CAMP-certified pulmonary function technicians performed tests of airway responsiveness to methacholine using a modified Chai protocol with the Wright nebulizer-tidal breathing technique (74). In CAMP and CAMPCS, airway responsiveness was determined annually. In CAMPCS/2, airway responsiveness was measured once, during year 3 or year 4.

Determination of inflammatory-related phenotypes (Specific Aims 1, 3, and 4)

Skin prick testing with a core battery of antigens (D pteronyssus, D farinae, cat, dog, American cockroach, German cockroach, Penicillium mix, Aspergillus mix, Timothy grass, and short ragweed), as well as a clinic-specific battery of locally relevant antigens, was performed twice in CAMP and once in CAMPCS, in accordance with the CAMP skin test protocol (75). Total serum IgE was performed by the DACI Laboratory at Johns Hopkins University, using standard radioimmunoabsorbant testing twice in both CAMP and CAMPCS and once by the local clinic laboratory during CAMPCS/2. Peripheral blood eosinophil count was measured by the local clinic laboratory twice in both CAMP and CAMPCS and once in CAMPCS/2.

Personal smoking in CAMP participants (Specific Aim 1)

There has been a substantial increase in cigarette smoking during CAMPCS/2 as patients have become older, with 21% currently smoking or reported smoking on at least one interim history form, with onset of starting smoking at age 17.0 +/- 2.1 years (mean +/-SD). These percentages are comparable to national rates (76). We also have data on maternal-reported smoking in utero and during the first 2 years of life from the original CAMP data for use in analyses of effects of these exposures on lung function growth and decline.

Asthma symptoms/morbidity and medication use (Specific Aim 1)

During CAMP, patients recorded daily symptoms, exacerbations requiring prednisone for rescue, and physician contacts because of asthma via daily diary. During CAMPCS and CAMPCS/2, patients were interviewed during clinic visits and twice yearly phone visits about symptoms and medications used in the 7 days prior to the interview, as well as other types of asthma medication (eg, prednisone) used since the last interview, and health care utilization for asthma. Information on nasal steroid use was also recorded. Asthma morbidity has been


Prelimin


assessed by: 1) numbers of times that a physician or a physician's office was telephoned because of asthma symptoms, that the patient was seen at a physician's office because of asthma symptoms, that the patient was seen at an emergency department or urgent care facility because of asthma symptoms, and that the patient was hospitalized overnight because of asthma symptoms; 2) number of days the patient was absent from school or work because of asthma symptoms; 3) numbers of times in the past 7 days the patient awakened during the night because of asthma, used albuterol because of asthma symptoms or low peak flow, or used albuterol for preventive use before exercise; and 4) frequency of coughing, congestion, and wheezing and association with colds and exercise.

Environmental measures

House dust was collected by a standardized protocol for quantitative measurements of major allergens (D pteronyssus, D farinae, cat, dog, and cockroach) once in the first 6 months of CAMP and a second time after the 3 year visit. Questions about the environment have been asked at each visit in CAMP, CAMPCS, and CAMPCS/2 using the same questionnaire. The detailed environmental data from early in CAMP will be used in analyses to examine effects of early life exposures in later life on maximally attained lung function. Relationships to other clinical characteristics will also be explored.

Patterns of growth and decline of lung function (Specific Aim 4, Hypothesis 5)


Prelimin


Data from the 44 CAMP participants age 23 or older were plotted with data from NHANES III (73) participants of the same sex and height (pre-bronchodilator for both CAMP and NHANES III). Four typical patterns are apparent (see Figure for examples from 4 patients): 1) Normal growth, no decline (32% of participants had this pattern), 2) Reduced growth (27%), 3) Normal growth then early decline (14%), and 4) Reduced growth, then early decline (27%). Overall, 41% (16 of 44) of the participants in this small subset have already started to decline -- an extremely abnormal pattern of lung function growth.

Somatic Growth (Specific Aim 3)

Linear growth was assessed 3 times per year in CAMP, 2 times per year in CAMPCS, and once per year in CAMPCS/2 (twice during the year when methacholine was done).

Preliminary data on genetic polymorphisms and lung function (Specific Aims 2 and 4)

The CAMP Genetics Ancillary Study Group has developed an approach to the multiple comparisons problem of looking at multiple SNPS and genes. Recently, the Family Based Association Test (FBAT)-approach has also been shown to be applicable to genome-wide association studies (77), outperforming standard multiple testing approaches such as FDR (78-80) by factors up to 40. Its application to a 100K-scan of the Framingham Heart Study revealed only the replicated association for BMI so far (81). We have utilized the screening algorithm of Lange and Van Steen (77, 82, 83) to generate preliminary data on the genetic determinants of FEV1/FVC ratio for this grant application. This algorithm, which will serve a vital role in the proposed candidate gene


Prelimin


evaluation, begins with estimation of the conditional power of the FBAT statistic, which depends on the effect size, all parental genotypes, and all phenotypic values (84). SNPs with highest conditional power are used for the subsequent FBAT testing, which is independent of the screening step. Thus, only SNPs with reasonable power are used for subsequent family-based analysis; SNPs with low power increase the multiple testing problem with minimal chance of demonstrating association. For this application we performed a preliminary analysis of our first 168 genes in CAMP to determine which, if any, were significantly related to FEV1/FVC ratio. Four genes, DPP10, GPRA, PTH11 and SERPINE2, all had multiple SNPs significantly associated with FEV1/FVC in CAMP.


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CAMPCS/3 Protocol 4. Methods

Methods

Overview of CAMPCS/3

CAMPCS/3 is designed as an extension of CAMPCS/2, which was an extension of CAMPCS, which was an extension of the transition phase of CAMP. The CAMP trial concluded with a transition phase, a 4-month period when study medication was withdrawn and children were monitored for lung function, airway responsiveness, growth, and asthma control. At the end of the transition phase, care for asthma was transferred to the physician who cared for the child prior to enrollment in CAMP. The CAMP study physician provided recommendations for asthma care to the family and the physician at this time. In CAMPCS/3, we are continuing followup and monitoring after the transfer of care. While the participant=s physician administers care, the CAMPCS/3 physician will provide recommendations and is a resource for advice about asthma care.

All CAMP participants are eligible to enroll in CAMPCS/3, including those who did not participate in CAMPCS or CAMPCS/2. We anticipate that 80% or more of those participating in CAMP will enroll in CAMPCS/3. Thus, we expect to have 830 participants in CAMPCS/3, aged 17-26 years, of whom 1/4 to 1/3 will be minority.

CAMPCS/3 will be a multicenter, cohort observational study with treatment for asthma managed by the participant=s physician. Recommendations for treatment in accordance with National Asthma Education and Prevention Program Expert Panel Report (NAEPP Guidelines) will be provided to the family and, if permitted by the family, to the child's physician. While the provision of medications was a benefit to patients during CAMP, we know from CAMPCS and CAMPCS/2 that lack of provision of medications will not be a major deterrent to participation. The bond between staff and patients is very strong, and many of the CAMP/CAMPCS/CAMPCS/2 physicians are the patients' asthma physicians to whom care was "transferred" following the close of CAMP.

CAMPCS/3 visits with patients will begin on 1 January 2008 and end on 31 March 2012. Patients will have one clinic visit for spirometry each calendar year from 1 January 2008 through 31 December 2010, and a final spirometry visit in the period 1 January 2011 through 31 March 2012. Patients will have one additional visit for methacholine testing between 01 July 2008 and 31 March


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2012. The CAMPCS/3 visits will allow patients and families to sustain the contact with the CAMP staff and will provide the reassurance of a second opinion on the asthma care received, while reducing the obligations of participation. The proposed data collection schedule is presented in Appendix 5.2.

The centers participating in CAMPCS/3 include the 8 clinics, the Data Coordinating Center (DCC), and the NHLBI project office. The Genetics Ancillary Study, initiated during CAMP, will continue with analysis of the DNA collected previously and will correlate the genotypic data with phenotypic data collected in CAMPCS/3.

Consent and recruitment in CAMPCS/3

CAMPCS/3 participants may be as young as age 17 at enrollment. Consent and assent statements will be used in CAMPCS/3 as required by each clinic=s IRB and their definition of adulthood. If a participant is considered not of an age to provide consent, the participant=s parent or guardian will be required to sign the consent statement for the participant to enroll in CAMPCS/3. The consent statement will specify the purpose of CAMPCS/3, the general design, the expected duration of the study, the data collection procedures and schedule, the risks and benefits associated with participation, the protections against risks, the alternatives to participation, the incentives to be provided, and the protections for confidentiality of the data provided by the patient and family. The assent statement will provide similar information in an age appropriate fashion. As in previous phases, prototype consent and assent statements will be developed and distributed to clinics, with the understanding that information thought to be essential to informed consent may not be deleted. IRB approval of the CAMPCS/3 protocol and consent and assent statements will be required at a clinic before patient activities may begin at the clinic. The DCC will collect copies of all approved consent and assent statements and will review them for completeness of information. The DCC will monitor for initial IRB approval at each center and annual renewal of approval, as has been done in CAMP, CAMPCS, and CAMPCS/2. The only exclusion criterion for participation in CAMPCS/3 is refusal.

Patient contact schedule and content of visits

The four yearly patient visits will be timed around the anniversary of the patient=s randomization in CAMP. Visit procedures will include spirometry, height and weight measurements, and interim health history and environmental exposures interview. There will be a fifth visit for methacholine testing that may be scheduled for any date during the latter half of year 1 through year 4.


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One week prior to each clinic visit, the study coordinator will contact the patient to remind the patient to bring all medications prescribed or in use for asthma to the visit, and to arrange for holding short-acting bronchodilator for 4 hours and long-acting bronchodilator for 12-24 hours before the visit.

At each visit patients will be queried about asthma medications taken in the past 7 days in detail (medication taken, dose, and number of doses taken) and types of asthma medication used since the last interview. Use of medications for other problems will also be recorded. Questions about chest symptoms, upper airway symptoms and treatment (rhinitis and sinusitis), and tobacco smoke and other environmental exposures will be asked. Pregnancy history will be queried since pregnancy may affect lung function assessment. Height and weight will be measured at each in-person visit.

At each clinic visit, symptoms and medication use will be used to recommend treatment in accordance with the NAEPP Guidelines to be used until the next clinic visit. The treatment recommendation will be transmitted to the asthma care physician via a letter to be sent after each visit (if the patient has given permission for release of his/her information to the primary asthma care physician). This letter will also transmit information about the results of the pulmonary function tests and any information about the interval clinical course.

Measurement and assessment methods

Pre- and post-BD FEV1 and FEV1/FVC ratio

Rationale: FEV1, a stable phenotype, is highly predictive of asthmatic attacks, is correlated with airway responsiveness and bronchodilator response, and predicts asthma severity. FEV1/FVC ratio decreases as a consequence of lung growth. Lower than normal ratios are thought to represent the degree of airflow obstruction in asthma and can be used to represent exaggeration of dysanapsis caused by asthma. Airflow obstruction, assessed by pulmonary function testing, is one of the defining characteristics of subjects with bronchial asthma. Therefore, spirometric measures, including FEV1 and FEV1/FVC, are essential physiologic phenotypes in the study of potential genetic influences in the development of bronchial asthma (116). Data collection: Spirometry will be assessed by methods used in CAMP (117). Spirometry is carried out by study-certified pulmonary function technicians. Pre-bronchodilator spirometry is performed at least 4 hours after the last use of a short-acting bronchodilator and 12-24 hours after the last use of a long-acting bronchodilator. In CAMPCS/3 spirometry will be measured pre- and post-bronchodilator during years 1-4 and


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pre-bronchodilator before the methacholine challenge.

Airway responsiveness

Rationale: The definition of asthma clearly emphasizes the central role of increased airway responsiveness. Characterization of asthma severity requires methods to ascertain this phenotypic trait (116). Data collection: Study-certified pulmonary function technicians perform tests of airway responsiveness to methacholine using a modified Chai protocol with the Wright nebulizer-tidal breathing technique (117). In CAMPCS/3 airway responsiveness will be measured one time only, to decrease participant burden and cost.

To minimize the effects of various factors and the course of asthma on methacholine responsiveness, determinations will not be made within 4 weeks of use of oral steroids for an asthma exacerbation, within 4 hours after the last use of a short-acting bronchodilator and 12-24 hours after the last use of a long-acting bronchodilator, or if the FEV1 at baseline is less than 70% of predicted. Patients will be screened for other contraindications to performance of methacholine challenge prior to initiation of the challenge. If the patient has had a upper respiratory infection in the previous 4 weeks, this is noted on the form. If the patient has consumed caffeine within 4 hours of the methacholine challenge, the test is done and the consumption of caffeine is noted on the form. Effort will be made to do methacholine challenge testing on any one patient at the same time of day as the child was assessed in CAMP, CAMPCS, and CAMPCS/2; the time the test ended will be noted on the form. Two 90 μg puffs of albuterol will be administered after methacholine challenge testing if the FEV1 is less than 90% of pre-diluent baseline. The patient will not be allowed to leave until the FEV1 is at least 90% of baseline. Methacholine solutions will be prepared at each clinic with Provocholine7 and according to the package insert for Provocholine7.

Somatic growth

Rationale: Linear growth is an important outcome of asthma. Results in the literature are mixed, and no study using randomized assignment to ICS and placebo has followed patients longitudinally into adulthood. Data collection: A protocol was established in CAMP to standardize measurement of height and weight (117). Standing height is measured with the Harpenden stadiometer (Holtain model #602 or #603). Weight is measured with the Detecto scale (model #337) with the patient wearing light clothing and socks or barefoot. In CAMPCS/3 linear growth will be assessed at each clinic visit.


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Symptoms/morbidity and medication use

Rationale: Need for medication to control asthma symptoms is an important outcome as well as a modifier of the clinical course, and is needed as a covariate of all outcomes of the study. Data collection: During CAMP patients collected information on symptoms, exacerbations requiring prednisone, physician contacts, urgent care visits, and hospitalizations for asthma via daily diaries and/or interviews during visits. During CAMPCS and CAMPCS/2, patients were interviewed during clinic and telephone visits to determine symptoms and medications used (dose and number of doses taken) in the 7 days prior to the interview, as well as all types of asthma medication used since the last interview. The same questions used in CAMPCS/2 will be used in CAMPCS/3. Questions about what the patient is taking will be asked in a nonjudgmental manner. Use of prednisone since the last contact will be queried. Information on nasal steroid use since the last contact will be recorded. Morbidity will be assessed as follows: 1) by contact with a physician: numbers of times that a physician or a physician's office was telephoned because of asthma symptoms, that the patient was seen at a physician's office because of asthma symptoms, that the patient was seen at an emergency department or urgent care facility because of asthma symptoms, and that the patient was hospitalized overnight because of asthma symptoms (these are answered with the number of relevant events in the interval since the last interview); 2) by absence from school or work: number of days the patient was absent from school or work because of asthma symptoms (these are answered with the number of relevant events in the interval since the last interview; 3) by asthma symptoms: how many times in the past 7 days the patient awakened during the night because of asthma, used albuterol because of asthma symptoms or low peak flow, used albuterol for preventive use before exercise; and 4) by symptoms precipitated by upper respiratory infections and exercise: questions about coughing, congestion, and wheezing (frequency and association with colds and exercise).

Environmental measures

Rationale: Environmental exposures to allergens, particularly those to which the individual patient is sensitized, and irritants are know to affect the course of asthma. Careful collection of these exposures over time will also allow studies of gene-by-environment. Data collection: A home environmental questionnaire was administered at CAMP baseline and annually thereafter throughout CAMP, CAMPCS, and CAMPCS/2. Questions from this form relating to household dust, heating systems, and other environmental factors will be asked at each CAMPCS/3 visit. The interview will also cover use of tobacco cigarettes,


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pipes or cigars by the patient and second hand exposure to tobacco smoke.

Atopy related phenotypes

Rationale: Atopy or allergy is a source of airway inflammation in asthma. Skin test reactivity to aeroallergens is correlated cross-sectionally with serum total and allergen-specific IgE levels, airway responsiveness, and asthma symptoms. In addition, it predicts subsequent decline in FEV1 in older adults (118). Various studies have demonstrated that serum total IgE is correlated with asthma and airway responsiveness (119-121). Eosinophils may play a major role in the development of airway inflammation and bronchial damage in asthmatic subjects (122). Peripheral blood eosinophilia is known to be associated with increased airway responsiveness and higher serum total IgE levels (122). Data collection: Presence of eczema will be queried at each visit as will presence of upper airway disease. Questions to assess the frequency and severity of nasal symptoms are derived from rhinitis and sinusitis quality of life and symptom questionnaires published by Juniper and colleagues (124-126), Bousquet et al (127), Gliklich and Metson (128, 129), Benninger and Senior (130), questionnaires used in the International Study of Asthma and Allergies in Childhood (ISAAC) and the Health Survey for Pediatric Asthma Patients in NHANES IV).

Pregnancy history

Rationale: Pregnancy can affect lung function and body mass index. Data collection: Since information on pregnancy was not collected in prior phases of CAMP, each female participant will be queried about past pregnancies (delivery dates) upon enrollment in CAMPCS/3. Participants will be queried about delivery dates since the last contact at subsequent visits and will be queried about current pregnancy at each spirometry session. Pregnancy is a contraindication for methacholine challenge; female participants are also queried about pregnancy prior to initiation of the methacholine challenge

Patient retention


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In informal discussions, patients have indicated that the bond with the study coordinators and physicians is the most important reason for staying with CAMP, CAMPCS, and CAMPCS/2. We plan to continue the $100 incentive per clinic visit for the participants in CAMPCS/3, as participants will be older, and many will be in college and/or have children of their own. Parents and the older participants have responded enthusiastically to education and updating on new information on asthma, particularly its treatment but also its pathophysiology. Education and information about asthma will be provided during the CAMPCS/3 visits. Throughout CAMP, CAMPCS, and CAMPCS/2, a few participants have required financial assistance to return for annual visits for data collection after moves away from the CAMP clinic area.

Data management for clinical data

A web based database management system patterned after the distributed database management system used successfully in CAMP, CAMPCS, CAMPCS/2 will be used in CAMPCS/3. The CAMP, CAMPCS, CAMPCS/2, and CAMPCS/3 databases will be maintained in separate but easily combinable databases. The data system for CAMPCS/3 will continue to have 2 components: the clinic data system and the clinic spirometry system. The major functions of the CAMPCS/3 data system will be:

1. Patient registration into CAMPCS/32. Data entry of forms3. Inventory of forms and visits keyed for each patient4. Database backup (daily, weekly, monthly)5. Generation of clinic management aids (labels, visit time windows guide,

reminders of upcoming and overdue visits)6. Printing sets of blank case-report forms

The key features of the entry process include:

1. Double entry of all data items2. Checks on patient identifiers 3. Range checking on all items on entry4. Within-form consistency and logic checks on entry5. Data entry screens customized to the forms6. 100% electronic audit trail of all entries, changes, and deletions to the

database7. Additional monthly consistency checks (with follow-up) done centrally at

the CC8. Monthly audits a sample of forms and error-rate tracking over time for


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each clinic9. Monthly performance reports by clinic sent to all clinics

A dedicated spirometry system will be used in CAMPCS/3. FEV1, FVC, FEV1/FVC ratio will be recorded. A written report of the spirometry or methacholine challenge session is printed at the close of the testing session.

Data management for genetic studies

Bioinformatics management system (ORAGEN)

A bioinformatics management system (ORAGEN) has been developed b y the Genetics Ancillary Study Group to handle their data for genetic studies. The ORAGEN application is presently used to track genealogical and lab-management data for their ongoing genetic studies. This application was written in Visual Basic, using the ORACLE database engine to manage relational data items. By relying on a robust and relational data structure, the ORAGEN application can easily manage and manipulate large quantities of phenotypic and genotypic data.

Management of genotypic data

Under the CAMP Genetics Ancillary Study protocol, blood samples collected in the CAMP cohort for DNA extraction were shipped to the Channing Laboratory where they were processed. Once samples were logged into the ORAGEN system, the system printed labels with unique barcodes assigned to each subject. Thus, processed specimens stored at the Channing Laboratory are not identified by name and do not have any of the original identifiers. At the Channing Laboratory, only authorized personnel are able to link these unique barcodes to a 12-digit ID number assigned to each study participant. Only the Principal Investigator can link this 12-digit ID number to the original identifier. After DNA was extracted, DNA aliquots were labeled with new unique barcodes and stored prior to genotyping.

Genotypic data have been carefully checked for errors and inconsistencies. Genotypes were assigned using semi-automated fluorescence scanning with the ABI GENESCAN/GENOTYPER software (Perkin-Elmer, Inc.). A random sample of 5% of any candidate gene genotyping performed at the Channing Laboratory will be redone at an independent laboratory to assure consistency and quality. The Channing Laboratory averages 1% discordancy on their genotype data and has 91-95% completeness for all the SNP's in their candidate genes.


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Management of phenotype data

The CAMP phenotypic data were incorporated into the GENERATIONS system via intermediate ASCII data files. These data files can be read directly into statistical programs such as SAS or exported in formats such as MLINK that are commonly used in statistical genetics. No individual identifying information on CAMP subjects is available at the Channing Laboratory; only the CAMP study identification number is used in the GENERATIONS system.

Quality assurance

The quality assurance procedures used in CAMP, CAMPCS, CAMPCS/2 will be replicated in CAMPCS/3. These are:

$ Certification of data collectors (e.g., clinic coordinator, pulmonary function technician, study physician, data entry technician); requirements for certification include practice with the procedure, completion of practice data collection forms, test of general knowledge of CAMPCS/3 protocol, reading of study manuals, and signature of a statement agreeing to abide by CAMPCS/3 protocol and acknowledging the need for accuracy and integrity in completion of study tasks and for preserving the confidentiality of the study and patient data.

$ Certification of clinics prior to initiation of data collection$ Ongoing feedback on performance in the form of monthly reports and

review of performance at study meetings$ Ongoing review of data collection forms by DCC staff and comparison of

paper forms to keyed data with feedback regarding and correction of discrepancies

$ Double entry of data collection forms$ Range checking during data entry and periodic batch editing to cover more

complex checks of consistency and completeness of the keyed data$ Periodic discussions at study meetings as to the importance of integrity in

this or any other research effort$ System specific and appropriate quality control procedures

The data forms and data system will be designed to exclude transmission of name and other personal identifiers to the DCC. Records will be identified by the CAMP ID number and code. Only these identifiers will be used in edit messages and correspondence with clinics concerning individual patients. Any forms received at the DCC (e.g., for quality control purposes) will be stored in a secure monitored area, with access limited to DCC personnel.


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Backup copies of the central master data file and program libraries will be generated at regular intervals. These backup files will be stored in a secure location, remote from the DCC, to permit regeneration of the master file, should it be destroyed by a computer malfunction, programmer error, fire, or vandalism.

Data monitoring

NHLBI will appoint an observational data and safety monitoring board for CAMPCS/3. The board will meet annually to review the performance of CAMPCS/3 and any safety issues that may arise. The board will review serious adverse events reported by the clinical centers.

Reports summarizing performance will be prepared at regular intervals by the DCC for distribution to and review by clinic staff, the Steering Committee, and the data monitoring board. The reports prepared will include a variety of tabulations which have been useful in CAMP, CAMPCS, and CAMPCS/2. Analyses will be performed comparing the clinics regarding rate of patient recruitment, completion of visits, and number of data collection deficiencies. Assessment of changes in performance will be based on comparisons within clinic involving, for example a comparison of the rate of data collection deficiencies in the most recent time period contrasted with rates observed in earlier time periods. While an overemphasis on competition can lead to problems, it has proven useful for investigators to know the standing of their centers, relative to others, with respect to the quantity and quality of the data supplied. Besides improving data quality, these reports also help maintain the sense of being part of a team with a common goal.

Human subjects

Characteristics of the proposed study population

The CAMP study population includes 1041 patients with mild to moderate asthma of whom 1035 survive. Patients were age 5-12 at initiation of screening for CAMP. As of 31 July 2007 (close of CAMPCS/2 patient visits), patients were age 17-26. 60% of the trial participants are male and 40% are female. There are 13.1% African American participants, 9.5% Hispanic, 68.4% white, and 9.0% other.

We expect that 80-85% patients enrolled in CAMP will enroll in CAMPCS/3. All clinical centers have plans to invite CAMPCS/2 enrollees as well as CAMP patients who did not enroll in CAMPCS or CAMPCS/2 to enroll in CAMPCS/3.


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Sources of research material

Data collected in CAMPCS/3 will be obtained by questionnaire, pulmonary function testing, and height and weight measurements.

Protection of human subjects

Protections for human subjects will include the consent process, linkage of patient records by ID number (name will be known only to clinic staff), and procedures for reporting and reviewing adverse events.

Consent. Written consent will be obtained from the participant if the participant is considered of an age to provide consent per the local institution=s definitions; written consent will be obtained from the parent and assent from the participant will be obtained if the participant is considered not of an age to provide consent. The goal of the consent process will be to provide each person approached with sufficient time and information to make informed decisions about participation in CAMPCS/3. The cornerstone for research on human beings is voluntary consent based on accurate information. The consent process is one of the more important patient-investigator activities because, if done properly, it serves not only to inform but also as a bonding experience. The bonding process is of particular importance in studies where participation extends over a period of years.

Adverse event monitoring. Although CAMPCS/3 will be an observational study with treatment managed by the patient's personal asthma care provider, the study will have a policy and procedure for reporting adverse events. The policy used in CAMPCS/2 is to report all serious adverse experiences judged by a study physician to be associated or possibly associated with the patient's prior treatment with CAMP study medication and all other serious, adverse events (e.g., death, intubation, life-threatening asthma exacerbation, or other life-threatening event). Events are reported to the DCC via narrative and the adverse event data collection form. The reports are then forwarded by the DCC to the clinics, the study chair, and the NHLBI project officer, with instructions to the clinics to submit the reports to their IRB as required by their institution. The reports are also forwarded to the data and safety monitoring board with a ballot asking each member to vote whether the event should be discussed in an immediate conference call or deferred until the next in person meeting of the board.

Confidentiality. Patients will be identified by ID number and code in the study database. Name will be known only to the clinic. The CAMP, CAMPCS, and


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CAMPCS/2 databases do not include patient identifiers except ID number and code; this policy will continue in CAMPCS/3. Clinics will be required to keep patient forms and other records in locking file cabinets or in a locked room used only by CAMPCS/3 staff.

Data analysis

General approach

Since the CAMPCS/3 data will come from continued, long-term observation of the original trial cohort, generalized linear regression models for the analysis of longitudinal data with continuous, binary, and event count response variables will be required to combine data across all phases of follow-up to address the Specific Aims for CAMPCS/3 (95). The choice of response and explanatory variables will vary depending on the Specific Aim; these choices are outlined below. Other, specialized methods are required for Specific Aim 2, Hypothesis 3 (genetics) and are discussed in section 4.11.5.

Spirometry measures for use in Specific Aims 1-3 will be maximally attained lung function measured after bronchodilator administration. For Specific Aim 4, CAMP values before bronchodilator will be used for comparison to the normal control values, as normal control values are available only without bronchodilator reversibility.

Depending on the Specific Aim, the data from the approximately m= 874 CAMPCS/3 participants can be expressed as yij and xijk, where yij is the applicable response measure and xijk is the value for the kth of p explanatory variables (predictors) on the ith participant at the jth time of measurement out of ni repeated measurements on the ith participant. We will assume that continuous response measures, such as FEV1, FVC, FEV1/FVC ratio, maximally attained FEV1 and FVC, log(FEV1PC20), height, and height velocity, follow a linear regression model:

yij = β0 + β1 xij1 + β2 xij2 + Y + βp xijp + εij

where εij are normally distributed errors associated with the ith measure at the jth time. When ni 2, the responses will be correlated due to repeated measures on the same participant, which requires special regression methods to determine SEs and P-values accurately. We will use generalized estimating equations with robust variance estimation (GEE) for this purpose. In some cases, e.g., for response measures expressed as change from baseline to the last available measure in young adulthood, ni =1 and the usual regression models


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may be used, although we will also use GEE in this case, since it offers the advantage of robust variance estimation. These models are very flexible and can be extended to include interaction terms needed to compare patterns of response between 2 or more groups across age, using regression spline terms to model complex age effects on response.

For responses such as counts of asthma exacerbations or for binary responses such as remission of asthma or not, we assume a generalized linear model regression applies where the mean response E(yij)=μij is related to the explanatory variables by:

h(μij) = β0 + β1 xij1 + β2 xij2 + Y + βp xijp ,

where h(.) is a link function such as log for counts or logit for binary responses. The GEE methodology can also be used to account for correlated responses in generalized linear regression models. Primary analyses will use all individuals with sufficient data on the variables used for a particular analysis. We expect that 80-85% of the original cohort of 1041 patients will be available for use in analyses. While this is a high rate of follow-up for a cohort followed since 1993, we will conduct additional, confirmatory analyses to assess the effects of missing data on inferences from the primary analyses. We will use the definitions and methods described in Pothoff et al (101) to perform approximate tests of whether the data are missing completely at random (MCAR) or missing at random (MAR). We do not expect the data to be MCAR, so we will conduct sensitivity analyses using both mixed random effect models and multiple imputation, which are still valid when the data are not MCAR, but are MAR. It is possible that some data may be missing and non-ignorable -- the probability that the data item is missing is related to the value of the data item. There is no way to test for this, since the missing data items are not available; however, it is possible to conduct sensitivity analyses making plausible (but untestable) assumptions using methods such as those in Robins et al (103). For all key publications, we will follow the recommendations for handling missing data in clinical trials given by Shih (102): (1) report frequency and reasons for missing data by treatment or other major comparison groups, (2) conduct sensitivity analyses as outlined above and discuss the implications of any discrepancies, found, (3) minimize missing data by maximizing patient retention, (4) make efforts to bring in patients with missing data for a final assessment at the end of follow-up, and (5) develop logistic regression models for the probability of missing data in analysis as a function of variables in the analysis and of baseline characteristics.

Measurement of steroid treatment


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The steroid treatment during the CAMP trial and its subsequent phases will be used to control for the effects of steroid treatment (oral and inhaled) on patterns of change in pulmonary function with age for the natural history analyses to address Specific Aim 1, Hypotheses 1-2. Since sicker asthmatics get more steroid medication (confounding by indication), controlling for the effects of steroid treatment will allow examination of the net relationship between symptoms, allergy measures, peripheral blood eosinophilia, airways responsiveness, and smoking on the natural history of the disease. Since all analyses are time dependent with the relevant exposure to ICS treatment during the interval before collection of outcome data, this information is obtained in sufficient detail in CAMP, CAMPCS, CAMPCS/2 and CAMPCS/3 to allow us to aggregate over these time periods to get a composite picture of the effect of ICS treatment on patterns of growth and decline of lung function. In Specific Aim 3, Hypothesis 4, the primary analysis will be an intention-to-treat comparison between ICS (budesonide) and placebo on attained maximal height and no adjustments for post-randomization treatment are appropriate. However, to help interpret any differences in attained height, the steroid treatments in the two groups will also be compared. We do not expect differential use of steroid treatment to be an issue, since we know that steroid use has been similar between the ICS and placebo arms in CAMPCS and CAMPCS/2.

Analyses for Specific Aim 1, Hypothesis 1

The primary analysis for this aim will use multiple linear regression models for responses (1) maximally attained lung function (FEV1 and FVC) during CAMPCS/3 and (2) progression of obstruction at the time of maximally attained lung function (FEV1/FVC) in relation to explanatory variables measured prior to the beginning of CAMPCS/3 and during CAMPCS/3: log FEV1PC20, bronchodilator response, skin test results, IgE (above/below median), peripheral blood eosinophil count and smoking exposure (personal and passive), height (at maximal maximally attained lung function),height2, gender, and ethnicity. Secondary analyses for Hypothesis 1, aimed at clarifying the natural history lung growth and the progression of childhood asthma into young adulthood, will use three longitudinal linear regression analyses of the full set of repeated measures since the beginning of CAMP on three response variables (FEV1 (L), FVC (L), and FEV1/FVC in relation to the explanatory variables log FEV1PC20, IgE (above/below median), peripheral blood eosinophil count and personal smoking exposure, controlling for age (using regression splines per year of age), height and height2 (the log FEV1PC20 response will not be controlled for the height terms), gender, and ethnicity, and on-going (i.e., time-dependent) asthma treatments (ICS vs. no ICS with indicators for other modalities). Effects and statistical significance will


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be determined by the regression coefficient of the appropriate explanatory variable. Since all the explanatory variables of interest are time-dependent, we will need to explore the appropriate lag-interval for relating the explanatory measures to the response variables.


The primary analysis for Hypothesis 2(a) will use multiple linear regression models for responses (1) maximally attained lung function (FEV1 and FVC) during CAMPCS/3 and (2) progression of obstruction at the time of maximally attained lung function (FEV1/FVC) in relation to measures related to lower respiratory symptoms (average cough/wheeze score during CAMPCS/3 prior to the attained maximally attained lung function), controlling for explanatory variables measured prior to the beginning of CAMPCS/3 and during CAMPCS/3: log FEV1PC20, bronchodilator response, skin test results, IgE (above/below median), peripheral blood eosinophil count and smoking exposure (personal and passive), height (at maximal maximally attained lung function), height2, gender, and ethnicity. Secondary analyses similar to those described for Hypothesis 1 above will be done, adding time dependent symptom scores to the longitudinal linear regression models. The primary analysis for Hypothesis 2(b) of this aim will use a multiple logistic regression model of the odds of persistent symptomatic asthma, (according to NAEPP guidelines) at the end of CAMPCS/3 in relation to explanatory variables measured prior to the beginning of CAMPCS/3 and during CAMPCS/3: log FEV1PC20, bronchodilator response, skin test results, IgE (above/below median), peripheral blood eosinophil count and smoking exposure (personal and passive), height (at maximal maximally attained lung function), height2, gender, and ethnicity. Effects and statistical significance will be determined by the regression coefficient of the appropriate explanatory variable. The same issues related to lag-intervals for the secondary analyses for Hypothesis 1 apply to the secondary analyses for Hypothesis 2(a).


Risch and Merikangas have shown that association studies can be a very powerful approach for finding genetic determinants of a complex disorder (96). Since CAMP has more than 700 family trios with DNA, the use of family-based controls obviates the potential for false-positive associations related to population structure. The transmission/disequilibrium test (TDT), which typically employs genotypic data from affected individuals and their parents, provides a test of linkage and association without bias from population stratification or admixture (97, 98). For family-based association analysis of FEV1, FVC, and FEV1/FVC in CAMP trios, the SNPs will be evaluated for their conditional power


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based on the conditional mean model approach by Lange (99). The SNPs will then be ranked as discussed in the algorithm by Van Steen (2005) (77, 100). In order to fully maximize the statistical power to detect true associations in the first stage of the testing strategy, as in Herbert et al. (81), we will use the FBAT-PC approach (82) with the CAMP pulmonary function data (longitudinal for both FEV1, FVC, and FEV1/FVC are available for 12 consecutive time points). Using the conditional mean model (99), the FBAT-PC approach estimates the genetic effect sizes for all repeated measurements and constructs an overall phenotype with maximal heritability. The overall phenotype is tested for association using the FBAT-statistic. As a rule of thumb (82), the overall phenotype constructed by the FBAT-PC approach has a single-SNP heritability that is about the sum of the estimated heritabilities for each repeated measurement that is included in the FBAT-PC approach (82). For the spirometric phenotypes in CAMP, single SNP heritabilities in the range of 0.5%-1% are realistic estimates (82), and the overall FBAT-PC phenotype can be expected to be in the range of [6%-12%] = [0.5%-1%]*12 measurements. In Herbert et al (81), the FBAT-PC approach was able to extract sufficient power from just 5 repeated BMI-measurements so that genome-wide significance could be established within one sub-sample of the Framingham Heart Study that contained only 200 families with 624 genotyped family members. We will then test our significant SNPs from the 550,000 for our three phenotypes (post-bronchodilator FEV1, FVC, and FEV1/FVC) first in the Sepracor/EMGB case control population then in the remaining 394 CAMP trios and finally in 600 trios from the recently refunded Asthma in Costa Rica R01 HL 066289 (ST Weiss PI). This three stage replication strategy takes maximal advantage of different study designs and multiple ethnicities to enhance the power of replication.


To determine the effects of 3.5 to 5.5 years of randomly assigned ICS therapy started in childhood, the primary regression analysis will be of the change from baseline to the last available post bronchodilator FEV1 % predicted in CAMPCS/3 in relation to indicator variables for assigned treatment group (budesonide vs. placebo and nedocromil vs. placebo), and asthma severity (mild vs. moderate) and duration at baseline. Secondary analyses will be carried out on other response measures: change from baseline to last available corresponding measure in CAMPCS/3 in, post bronchodilator FVC % predicted, post bronchodilator FEV1/FVC, log FEV1PC20, and height. The explanatory variables will consist of two indicator variables for assigned treatment group (budesonide vs. placebo and nedocromil vs. placebo); age, gender, ethnicity (except for the % predicted responses which are, by definition, controlled for age, gender, ethnicity and height); and asthma severity (mild vs. moderate) and


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duration at baseline. The primary effect associated with each response will be determined by the size and statistical significance of the budesonide vs. placebo indicator variable. Interpretation and analysis of the results of these intention-to-treat comparisons are complicated by potential differential asthma treatment patterns over time after the end of the CAMP trial phase; however, this does not appear to be an issue, since data on use of ICS during CAMPCS ranges from 52-54% across the three groups (P=0.82) and ICS use as of the most recent visit in CAMPCS/2 was nearly identical across treatment groups at 37% (P=0.96).

Analysis for Specific Aim 4, Hypothesis 5

Hypothesis 5(a) requires classification of each subject into one of the 4 pre-defined patterns of reduced lung function and decline using the methods outlined in section 4.14. Percent agreement and kappa statistics will be calculated to establish the validity of the classifications. For Hypothesis 5(b), linear discriminant function analysis for four groups will be carried out to identify clinical characteristics, pulmonary function measures, and inflammatory markers available at the start of the CAMP trial that discriminate among the groups. This analysis will be repeated using the same measures available at the beginning of CAMPCS/3 as discriminators. In addition, polychotomous (four category) multiple logistic regression models will also be used to cross check findings from the linear discriminant analyses to mitigate issues with non-normality of the candidate discriminator variables.

Sample size considerations - all Specific Aims

The CAMP trial (104) was designed to recruit 960 patients to detect a 3.5% difference (between each active treatment group vs. placebo in the change from baseline post-bronchodilator FEV1. The calculation assumed a two-sided Type I error=0.01, power=0.90, within group SD=11% for the change from baseline response, 10% lost to follow-up rate, and a 1:1:1.4 allocation ratio for budesonide:nedocromil:placebo treatment groups. These rigorous design specifications proved to be conservative, since recruitment totaled 1041 patients, and both the within group SD and loss to follow-up rate were more optimistic than anticipated at 9.8% and 7% respectively. Allowing for a higher loss to follow-up rate of 15%, with approximately 874 patients, CAMPCS/3 will have power=0.96 to detect a 3.5% difference in the FEV1 change measure with a Type I error of 0.01 and within group SD of 10%. With regard to other response measures, the sample size of 874 patients is adequate to detect small effects (0.31SD) for other outcome measures across treatment groups with power=0.90 and Type I error= 0.01. Comparisons between 2 groups (not necessarily treatment groups) will be able to detect effect sizes from 0.26 to 0.44 SD units,


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assuming the proportion of the total sample size in the smaller of the 2 groups ranges from 0.1 to 0.5 and assuming n=874, power=0.90 and Type I error=0.01. For example, the estimated SD of maximally attained lung function derived from the 44 CAMPCS/2 patients currently aged 23 or older is 0.69L, which implies the ability to detect differences across groups with power=0.90 and Type I error=0.01 in mean maximally attained lung function ranges from 0.18L to 0.30L. Since estimated SDs from regression models will be smaller than total SD estimated from the 44 patients, effective detectable differences in CAMPCS/3 will be smaller than the range just stated.

Statistical power for multistage whole genome association analysis, Specific Aim 2, Hypothesis 3

To assess the power of our multi-stage design, we used a mixture of simulations studies and analytical power calculations. The power of the population-based case/control studies was estimated based on simulation studies in R. The power of family-based studies was computed with using PBAT. The power of the testing strategy by Van Steen was predicted based on simulation studies in R using the R-interface with PBAT. Since the first 2 stages (screening and testing in the 400 trios and testing in Sepracor/ENGB)) in Specific Aim 2 are analyzed jointly and the significance is established based on the combined p-values of both stages, we used simulation studies in R to estimate the overall power level of the first 2 stages in Project 1 of the PO1. The power to detect a SNP with a true association in stages 1 & 2, and to push it forward to the 3rd stage (replication in the other ethnic groups) is defined by the probability that both the SNP with true association achieves a conditional power estimate in the first stage that is among the 3000/4=750 highest power estimates for all 550,000 SNPs and that its combined p-value from the FBAT-statistic in stage 1 and the score-test in stage 2 is significant at an adjusted alpha level of 5%/3000. We used simulation studies with 1000 replicates to estimate the power of this procedure. In the first step, we simulated 400 trios with 550,000 SNPs. For the SNPs that are not associated with the any of phenotypes, we simulate an allele frequency from a beta-distribution that resembles the allele frequency distribution of the 500K chip. The parental genotypes were then generated by assuming that Hardy-Weinberg equilibrium holds and the offspring genotypes were constructed by Mendelian transmissions from the parents. For a SNP that is associated with a quantitative trait, we simulate the phenotype and the genotype configuration of the trio as described in (83). For the quantitative phenotypes, we measured the genetic effect size in terms of heritability/standardized genetic effect size, i.e. the amount of phenotypic variance that is explained by the single SNP, assuming that the phenotype is normally distributed and the mode of inheritance is additive.


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The combined power of stages 1&2 was assessed in the following way. For each phenotype ( the 3 selected quantitative traits FEV1, FVC and FEV1/FVC ratio), we estimated the conditional power of the corresponding FBAT-statistic for all 550,000 SNPs, using the approach by VanSteen for the quantitative traits. Then all 550,000 SNPs were ranked based on their power estimates and the 3072/4=768 SNPs with the highest power estimates were pushed forward to the 2nd stage of the strategy (testing in Sepracor/EMGB). In the 2nd stage, we generated the genotype distribution for the SNPs that are not associated with the selected phenotypes based on the Hardy-Weinberg assumption. For the SNPs associated with one of the 3 quantitative phenotypes, we generated the genotype distribution based on the Hardy-Weinberg assumption and simulated the phenotype as a normal random variable with a heritability of 1/12th of the original heritability of the family sample. We will apply the FBAT-PC approach to 12 repeated measurements in the CAMP study, but will have only 1 cross-sectional measurement available in the Sepracor/EMGB study. For each phenotype, we then compute the score-test in the Sepracor/EMGB study and the FBAT/FBAT-PC test in the CAMP study for all 3000 SNPs that are genotyped in stage 2. For each phenotype, we combine the p-values from stage 1 and stage 2 using Fisher=s method (105). If a combination of SNP and phenotype had a combined p-value that is less than 5%/3000, it is declared to be significant.

Study organization

The CAMPCS/3 Steering Committee will be comprised of the principal investigators from each of the participating centers, the NHLBI project officer, and a representative from the clinic coordinators. The Steering Committee will be responsible for the design and conduct of CAMPCS/3 and will meet monthly by conference call. The Publications Committee, a subcommittee of the Steering Committee, will be responsible for organization and oversight of development of manuscripts.

Use of comparison populations to describe abnormal patterns of growth and decline of lung function (Specific Aims 4, Hypothesis 5)

CAMP spirometry values will be compared to 3 sets of non-asthmatic comparison populations: Vlagtwedde/Vlaardingen (4, 30, 41), NHANES III (73), and CARDIA (13):

1.Vlagtwedde/Vlaardingen: The Vlagtwedde/Vlaardingen cohort study is unique in having a 30-year follow-up of individuals between the initial ages of 15-35


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years in two Dutch towns. All individuals in the two towns were surveyed every 3 years. The subjects are representative of the Dutch population. Information is available on lung function (FEV1 and VC), airway responsiveness to histamine, respiratory symptoms (including asthma diagnosis), cigarette smoking and allergy (peripheral blood eosinophil counts, skin tests, and IgE). A total of 1818 male and 1732 female subjects contributed at least one pulmonary function test value in the age range of 15-35 years, and the total numbers of observations are 4378 for males and 3716 for females. We have extensive experience working with these data and Dr. Weiss has written 17 papers on the data from this study.

2. NHANES III: The third National Health and Nutrition Examination Survey was conducted from 1988 to 1994, and it comprised a random sample of the U.S. population. Spirometry data were collected in a standardized manner, with quality control conducted by National Institute of Occupational Safety and Health. 20,627 individuals age 8 years or older participated. 7429 subjects were asymptomatic, lifelong non-smoking subjects with at least 2 acceptable maneuvers and their data allowed development of reference equations to describe normal pulmonary function for 3 major race/ethnic groups: Caucasians, African-Americans, and Mexican-Americans. As can be seen from our preliminary data, we have used non-asthmatic subjects as a comparison population for lung growth analyses.

3. CARDIA: The Coronary Artery Risk Development in Young Adults Study examined 5115 black and white men and women aged 18-30 at baseline in 1985-6, with re-examination 2, 5, and 10 years later of 4624, 4352, and 3950 participants, respectively. Subjects were randomly sampled in Birmingham, AL, Chicago, IL, Minneapolis, MN, and Oakland, CA. Questionnaires asked about demographic characteristics, respiratory health, cigarette smoking, physical activity, and medical history. Standard procedures of the ATS were followed for measurement of lung function using a water sealed spirometer. We have obtained permission from the CARDIA group to use this data set and we will use the available questionnaire data to identify non-asthmatic individuals within the CARDIA population.


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Since CAMP is a longitudinal follow-up of children starting in 1993, none of these sets of normal subjects was examined concurrently with CAMP; however, these comparison populations share a broad range of important characteristics, being national (NHANES and CARDIA) and international (Vlagtwedde/Vlaardingen), longitudinal (CARDIA and Vlagtwedde/Vlaardingen) and a cross-sectional representative sample of the US population (NHANES), with all 3 comparison groups containing extensive data in the 20-30 year old age group in which CAMPCS/3 will focus. There is good overlap of time of study with CAMP for Vlagtwedde/Vlaardingen, NHANES, and CARDIA. Taken together these populations have the range of variables needed for comparison to CAMP participants, and provide comparison groups that will allow us to define the magnitude and range of abnormal patterns of maximal attained lung function and early lung function decline into young adulthood in subjects with persistent childhood Most importantly, the effects of biases due to age, period, and cohort effects can be minimized by seeking patterns of abnormality that are consistent in comparisons to the two longitudinal populations and to the nationally representative cross-sectional sample.

Methods for defining patterns of reduced lung function growth and early decline of lung function

Four patterns for classification have been identified in our Preliminary Data (C.4.8): normal lung growth and no decline, reduced lung growth, normal lung growth then early decline, and reduced lung growth then early decline. These patterns correspond to the patterns demonstrated by individuals who acquire fixed airflow obstruction from asthma depicted in the schematic in 3.2.7. We will not be able to reliably distinguish individuals in the schematic who exhibit rapid decline, as this pattern typically emerges in the late 20s and will not become established sufficiently with the 20-30 year age range at the end of CAMPCS/3.

Each CAMPCS/3 patient will be independently classified three times by each of two pulmonologists (a total of six classifications) into one of the four lung growth patterns using comparisons of locally weighted smoothed scatterplots (lowess smoothing) of all longitudinal post bronchodilator measures on a patient plotted by age with superimposed and similarly smoothed age, gender, and height adjusted expected curves from each of the three reference populations of non-asthmatics: NHANES III, Vlagtwedde/Vlaardingen, and CARDIA. Each graph will also have a reference line consisting of the ratio of observed to expected with reference lines drawn a 0.9, 1.0, and 1.1.

Assignment to a specific pattern will be made if four or more of the six classifications are to that pattern. Otherwise, discrepant pattern assignments


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will adjudicated by a third pulmonologist at the Data Coordinating Center. The graphs will be identified with a code # only to mask the pulmonologists regarding patient and reference population. Duplicate readings will be made on a random 10% sample of the graphs, which will be inserted randomly into the set of graphs to be read. Inter- and intra-observer agreement kappa statistics will be calculated to assess the reliability of the four category classification. These statistics will be generated periodically throughout the process. After the first 100 patients have been read, the pulmonologists will meet to discuss discrepancies and to refine the definitions below, if needed.

Following the clinical convention used for determining an exacerbation in chronic obstructive pulmonary disease (1), a value of 10% below a non-asthmatic reference curve will be considered lower than normal Working descriptions of the 4 patterns are as follows:

1. ANormal lung growth, no decline@: CAMP values are within 10% of normal throughout the range.

2. AReduced lung growth@: CAMP values are at least less than 90% of normal throughout the range, but the values do not decrease further by more than 10% from the initial low value.

3. ANormal lung growth then early decline@: CAMP values are initially within 90% of normal and then decline by more than 10% and stay below this value for the duration of the range.

4. AReduced lung growth, then early decline@: CAMP values are initially less than 90% of normal and then decline by more than 10% and stay below this value for the duration of the range.

It is likely that there will be patterns that do not fit one of the four descriptions above, although we did not see this in the 44 patients evaluated to date. For instance, we may see decline followed by increase to the previous baseline (present before the decline). If additional patterns occur, we will include them in our analysis providing there are a sufficient number of subjects with the pattern.


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CAMPCS/3 Protocol 5. Tables

Appendices

5.1. Design summary..................................................................................35

5.2. Data collection schedule......................................................................37


Tables

CAMPCS/3 Protocol 5. Appendices

Design summary

Name$ Childhood Asthma Management Program Continuation Study/ Phase 3 (CAMPCS/3)

Objective$ Extend follow-up study of the cohort established by the Childhood Asthma Management

Program (CAMP) for an additional 4 years to study the determinants of lung growth and progression of obstruction due to persistent childhood asthma.

Type of study$ Multicenter, long-term follow-up, cohort study

Population$ 830-880 participants in CAMP, aged 17-26 years, of whom 1/4 to 1/3 are minority

(anticipated)

Treatment$ Prescribed by the patients=s physician$ Consultation of treatment provided by CAMPCS/3 physicians at the time of the annual

visit; advice provided will consider history of asthma symptoms, quality of life (activity, school and work missed), medication use, and pulmonary function, and will be based on the NAEPP Guidelines

Inclusion criteria$ Participant in CAMP$ Consent of the participant or consent of guardian and assent of minor child

Exclusion criteria$ Refusal

Recruitment$ As soon as IRB approval is obtained; at any time during CAMPCS/3


Design


Duration of patient followup$ 4 years

Outcomes$ Rate of increase and maximal level of lung function (FVC, FEV1, FEV1/FVC)$ Rate of increase in or maximal attained level of height$ Airway responsiveness to methacholine$ Occurrence, relapse, or remission of respiratory symptoms$ Use of asthma medications$ Use of health care services

Measures of independent and mediating variables$ Treatment used by the patient$ Environmental exposures$ Manifestations of atopic status$ Duration of asthma

Calendar period of patient visits$ 1 Jan 2008 through 31 Mar 2012

Visit schedule$ Visit y1: any time from 01 Jan 08 - 31 Dec 08$ Visit y2: any time from 01 Jan 09 - 31 Dec 09$ Visit y3: any time from 01 Jan 10 - 31 Dec 10$ Visit y4: any time from 01 Jan 11 - 31 Mar 12$ Visit ym: any time from 01 Jul 08 - 31 Mar 12

Data collection schedule$ Pre- and post-bronchodilator spirometry: yearly$ Methacholine challenge: once$ Height and weight: at every visit$ Interim history (medication use, symptoms, health care utilization): at every visit$ Environmental exposures: at every visit


Design


Data collection schedule

Visits

Y1 Y2 Y3 Y4 Ym

Pulmonary function - Spirometry x x x x . - Methacholine challenge* . . . . x

Physical growth and development - Standing height x x x x x - Weight x x x x x

Respiratory symptoms x x x x x

Interim medical history x x x x x

Treatments used x x x x x

Environmental exposures - Home characteristics x x x x x - Tobacco smoke x x x x x - Job exposures x x x x x

Atopic disease -- manifestations - Eczema x x x x x - Upper airway symptoms x x x x x

*ym may occur at any time between 01 Jul 2008 and 31 Mar 12


Data_sch

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