CFRD GUIDELINES UPDATE

Dr Nigel Paterson, respirologistTracy Gooyers, nurse case managerPat Leggatt, dietitian

Overview

Introduction Epidemiology Screening Diagnosis Management Complications

Epidemiology

Prevalence 40-50% of adults with CF 20% of adolescents with CF Rare in childhood

In London CF clinic 18/80 (23%) CFRD 14/80 (18%) IGT Untested/infrequently tested (~5%) Some intermittent IGT

Introduction – CF Related Diabetes

A distinct clinical entity Neither Type 1 nor Type 2 Diabetes Risk for microvascular, not macrovascular

disease Significant impact on pulmonary function

Shares features of both T1DM/T2DM Insulin resistance Insulin insufficiency

Variants CFRD with Fasting Hyperglycemia (+FH) CFRD without Fasting Hyperglycemia (-FH)

Screening

Significance Often clinically silent Nutritional and pulmonary consequences

Weight loss Protein catabolism Lung function decline Mortality

Screening

General Recommendations × HbA1C (insensitive, poor +ve predictive value)× CGM (intermittent high BG non-diagnostic)× FPG (fails to detect CFRD –FH)× SMBG (devices are inaccurate)√ OGTT (recommended method)

Screening

Annual screening Annual screening in asymptomatic patients 2h 75g OGTT After 10 years of age in all pt with CF

Other indications Acute pulmonary illness requiring IV

antibiotics or glucocorticoids Continuous enteral feeding Pregnancy Transplant patients

Recent Admission

2 week admission 1st week daytime BG 3 – 5s

Before evening tube feeds 2 – 4s During feeds 4 – 7 (one 12.1)

OGTT mid stay 5.0 & 12.6 mmol/L 2nd week daytime 3 – 7s

Once established on tube feeds (2500 – 3000 kcal in evening)

9.8 prior to feed 7 – 13s mid feed ( one 5.8) 4 – 10 post feeds

Screening - Inpatients

Significance 8 pt admitted with pulmonary exacerbation Normal random FPG 2 hr IVGTT 14.5 mmol/L (intermittent glucose

intolerance) Baseline FEV1 predictor of poor glucose

tolerance J Cyst Fibr May; 9(3): 199-204

Look for hyperglycemia in unwell CF patients!

Diagnosis

Based on standard ADA criteria 2h 75g OGTT > 11.1mmol/L FPG > 7.0mmol/L *HbA1C > 6.5% Casual BG > 11.1mmol/L + symptoms of

hyperglycemia Insufficient data for lowering these

thresholds in CF

Acute Pulmonary Exacerbation Acute illness requiring IV antibiotics or

systemic glucocorticoids can lead to hyperglycemia

Screening First 48hr Fasting and 2hr post-prandial blood glucose

Diagnosis Diagnostic criteria persist > 48hr Correlated with risk for microvascular

disease

Pregnancy

Pregnancy is a state of insulin resistance Screening

Women planning pregnancy or are pregnant

For GDM: 12-16 weeks and 24-28 weeks For CFRD: 6-12 weeks post-partum if GDM

Diagnosis of GDM by 75g OGTT FPG > 5.1mmol/L 1hr > 10.0mmol/L 2hr > 8.5mmol/L

Enteral Feeding

Screening Mid and immediate post-feeding plasma

glucose At initiation of gastrostomy feeding Monthly by SMBG (Confirm by laboratory)

Diagnosis If criteria are met on two separate days

Transplant Patients

For CF transplant patients Universal need for insulin peri-operatively Many need insulin long-term

Screening Pre-operatively by OGTT

Management

Care team Regular meetings Multidisciplinary approach Experts in CF and diabetes Education on self-management Communication between providers

Management – CF Diet

Doesn’t blend well with group DM classesCarb counting: insulin best approach for manyNo significant change to CF diet

High Calorie, High Protein, High Fat, Liberal Salt intake

Variable intake with focus on eating as much as wishes

Adjust simple carbohydrates through day or with food

Some have developed poor eating behaviors Artifical sweeteners not usually recommended

Use of supplements (Scandishake, Ensure Plus e.g) as indicated by BG

Management - Diet

CF Diet 2500 - 7000 kcal/d Up to 7 – 9 carb choices per meal, 3 or

more for snacks For those using pancreatic enzymes

assume a malabsorption factor about 10 – 15%

Management

Pharmacological Individualized insulin therapy

FH positive - basal and MDI or pump FH negative – MDI

Effects of adding basal are unknown

Oral agents less effective than insulin

Management

Goals same as other diabetes patients A1C < 7% FPG/preprandial PG 4.0 – 7.0 mmol/L 2hr postprandial PG 5.0 – 10.0 mmol/L

5.0 – 8.0 if A1C > 7% Monitoring

SMBG 3x daily if on insulin Quarterly A1C

Exercise encouraged

Complications

Acute Hypoglycemia Rare: DKA, hyperosmolar hypoglycemia

Chronic Microvascular – more common in FH

positive screening

Pulmonary Gastroparesis

Complications

Screening Annual screening

Spot Albumin:Creatinine Ratio (ACR) Dilated eye exam Neurologic assessment and foot exam Regular BP measurements Lipid profile if sufficient exocrine pancreas or

risk factors for cardiovascular disease Begins 5 years after date of onset if known Otherwise, immediately upon first diagnosis