Post on 27-Oct-2018
Luís Pereira-da-Silva
Hospital de Dona Estefânia, CHLC, EPE
Faculdade de Ciências Médicas, UNL
Escola Superior de Tecnologia da Saúde de Lisboa, IPL
Braga, May 12th 2012
NUTRITIONAL ASSESSMENT
OF THE NEWBORN AND SMALL INFANT
Clinical, Biochemical and Body Composition Indicators
I. Clinical indicators (Anthropometry)
II. Biochemical indicators
III. Body composition
Methods for nutritional assessment
I. CLINICAL INDICATORS
(ANTHROPOMETRY)
Anthropometry as a method
Advantage: The most simple and inexpensive among
noninvasive methods convenient tool for bedside
evaluation Lafeber. Clin Perinatol 1999, Pereira-da-Silva in: Preedy ed.
Anthropometry, Springer 2012
Disadvantage: Indirect method with limitations inaccuracy
and non validated measurements in neonates De Bruin. AJCN
1995
Anthropometry – the interests
1. At birth: Diagnosis of fetal malnutrition anticipation of
early metabolic risk
2. Neonatal period and early infancy: Assessment of the
nutritional status (guiding the clinical practice)
3. Early indicators of late metabolic syndrome
(adolescence/ adulthood)
Pereira-da-Silva in: Preedy ed. Anthropometry, Springer 2012
Anthropometry - Measures
Direct measures: weight, length, head circumference
(HC), mid-arm circumference (MAC), skinfolds…
Derived measures: ponderal index, body mass index ,
MAC:HC ratio, mid-arm cross sectional areas…
Pereira-da-Silva in: Preedy ed. Anthropometry, Springer 2012
Weight
The most used measure
High accuracy and reproducibility
Incubators with incorporated
scale
However – the body weight
does not give any information on
body compartments and quality of
growth
Gibson. Horm Res 2003
To be used:
At birth reflecting intrauterine nutrition
First postnatal weeks (preterm infant) evaluation of
the nutritional support
First postnatal months (preterm infant) evaluation
of medium- long-term growth
Weight
Reference curves
Weight
Fetal malnutrition and early metabolic risk Olsen IE, et al. Pediatrics 2010;125:e224
Reference values at birth for: weight, length and HC< > gestational age < >
gender; centiles 3 to 97
Small for-gestational-age (SGA) risks: hypothermia, hypoglycemia,
hypocalcemia, necrotizing enterocolitis (preterm)
Large for-gestational-age (LGA) risks: hypothermia, hypoglycemia,
polycithemia
Constitutional SGA and LGA
Birth weight BMI in adulthood
Curhan. Circulation 1996
Cohort USA: 71.100 neonates 22.846 men at 56 yr J shape curve
Undernutrition Overnutrition
BMI
Weight Nutritional assessment – At birth
Olsen IE, et al. Pediatrics 2010;125:e224
x
E.g.: 32 wks, BW1000, < centile 3 equivalent to < -2SD
z-score calculation: 1823–1000 = 823; 823:306 = -2,68 SD
Weight
Nutritional assessment – First postnatal weeks
Reflect the current clinical
assistance (12 NICUs in USA)
Include: weight, length, HC and
mid-arm circumference
Specific reference values for
SGA, and main comorbidities
(HMD, NEC, BPD…)
http://pediatrics.aappublications.org/cgi/content/full/104/2/280
Ehrenkranz. Pediatrics 1999;104:280
Weight
Nutritional assessment – First postnatal months
Useful for postdischarge follow-
up (up to 50 weeks corrected GA)
– curves for weight, length (lean
mass, and HC (brain)
http://www.biomedcentral.com/1471-2431/3/13 Fenton TR. BMC Pediatr 2003;3:1
Length
Rough indicator of the lean mass; Reflects the skeleton growth Koo. J
Nutr 2000; Gibson. Horm Res 2003
The accurate measurement is of utmost importance when length is
included squared or cubed in indices (BMI, ponderal index)
However Accurate crown-heel length measurement is not easy in
neonates, specially in full-term neonates
Length measurement technique
Conventional method: difficulty in
extending the lower limbs
accuracy reaction to the
discomfort (Neonatal Facial
Coding System) caused by full
extension - equivalent to heel
prick
Pereira-da-Silva. Acta Paediatr 2006
Validation of an alternative method
Length measurement technique
Length measurement technique
Alternative method:
Extending only one lower limb
(the trunk axis should be at a right
angle with the line between the
ileac crests)
Easer, maintains the accuracy
while reducing significantly the
discomfort
Pereira-da-Silva. Acta Paediatr 2006
Head circumference (HC)
Reflects the growth of the brain
the HC is reduced in
cases of severe and
prolonged intrauterine
undernutrition.
Freedman. Science 1980
Mid-arm circumference (MAC)
Reflects the combined arm
muscle and fat compartments
indirect indicator (with limitations)
of the body fat and protein
reserve Georgieff. Clin Perinatol
1986
Pereira-da-Silva in: Preedy ed. Anthropometry,
Springer 2012
Skinfolds
Estimate the subcutaneous fat,
assuming that the measured sites
represent the average thickness of
the subcutaneous fat layer
More used skinfolds: triceps and
biceps (peripheral fat),
subscapular and suprailiac (trunk
fat)
Lukaski. Am J Clin Nutr 1987
Pereira-da-Silva in: Preedy ed.
Anthropometry, Springer 2012
Skinfolds
Male TS
(mm)
BS
(mm)
SBS
(mm)
SPS
(mm)
GA
(wks)
Mean SD Mean SD Mean SD Mean SD
32-33 2.59 0.58 2.31 0.63 2.49 0.56 1.73 0.52
34 3.07 0.70 2.42 0.69 2.89 0.80 2.20 0.67
35 3.25 0.61 2.61 0.62 3.03 0.64 2.30 0.63
36 3.44 0.84 2.77 0.79 3.25 0.78 2.53 0.75
37 4.05 0.98 3.46 0.91 3.77 1.01 3.15 0.85
38 4.03 0.85 3.47 0.83 3.69 0.80 3.17 0.76
39 4.21 0.84 3.61 0.89 3.92 0.90 3.32 0.76
40 4.23 0.83 3.63 0.83 3.95 0.85 3.35 0.74
41 4.26 0.88 3.68 0.77 3.94 0.79 3.43 0.78
Rodriguez. Eur J Pediatr 2004
Central to total skinfold
ratio (CTS)
CTS = (SPS+SBS)/
(TS+BS+ SPS+SBS)
Estimates the central
(troncular) fat
CTA – Not validated
yet
GA
(wks)
Male Female
32-33 47.24±3.93 48.70±4.14
34 47.87±3.73 48.80±4.16
35 47.55±3.18 49.17±3.02
36 48.28±3.24 49.03±3.08
37 47.87±3.01 49.48±3.05
38 47.64±3.12 48.71±3.09
39 48.04±3.25 48.76±3.30
40 48.17±3.06 49.15±3.47
41 48.13±3.19 49.06±3.52
Rodriguez. Eur J Pediatr 2004
Skinfolds
As indicators of total body fat (TBF):
Good correlation (DEXA) Schmelzle. Am J Clin Nutr 2002; Koo. Pediatr
Res 2004; Ahmad. Am J Hum Biol 2010
Poor correlation (MRI) Lapillonne. J Pediatr Endocrinol Metab 1999;
Olhager. Acta Paediatr 2006
Skinfolds
Limitations in estimating the TBF in neonates:
Do not reflect the non-subcutaneous fat; TBF = subcutaneous fat + non-
subcutaneous fat (intrabdominal)
Rapid changes in fat distribution during the neonatal period
The hydration status affects the skinfold compressibility
Accurate measurement requires skill and training (high inter-observer
coefficient of variation)
Skinfolds
Prins. Pediatric Rev Commun 1995
Pereira-da-Silva in: Preedy ed. Anthropometry, Springer 2012
Derived Measures
Certain indexes and formulas associate direct measures and are
capable to predict the body composition and the nutritional status
better than each value on its own
WHO Tech Rep Ser. 1995
INDEXES
based on Weight and Length
1. Ponderal index (W / L3) x100
2. Adiposity index – Body mass index (W / L2)
3. Weight/ Length ratio (W / L)
4. Benn index (W / Ln)
5. Individualized Weight/ Length ratio
Tamim. J Perinat Med 2004
Ponderal index (IPI) W / L3 x100
Used to define types of IUGR:
Late IUGR in gestation – only
weight affected Low PI:
Asymmetrical IUGR
Early IUGR in gestation –
weight + length affected
Normal PI : Symmetrical
IUGR
Normal neonate
Normal PI
Low PI
Asymmetrical IUGR
Normal PI
Symmetrical IUGR
G A40 weeks, ♂
BW 2400 g (SGA)
Length 49 cm
PI = 2.0
Weight (g) x 100/ Length3
(cm)
Asymmetrical IUGR
Lehingue. Am J Hum Biol1998
X
Ponderal index
Type of IUGR
Asymmetrical IUGR – risk
of: asphyxia,
hypothermia,
hypoglycemia and
hypocalcemia
Fay. Aust N Z J Obstet Gynecol
1991
(neonate on the right)
Ponderal index
Symmetrical IUGR - risk of:
poor neurodevelopment and
growth outcome
Berg. Early Hum Dev 1989
Causes: Early and prolonged fetal
malnutrition; Intrauterine infection;
Toxics / Drugs;
Cromosomopathies; Syndromes;
Constitutional
Ponderal index
Type of IUGR
Mid-arm circumference / Head circumference
(MAC:HC ratio)
The HC is used in the denominator as constant, assuming that in
acute protein-energy malnutrition the brain is relatively spared
compared to muscle and fat wasting Freedman. Science 1980
MAC: reflects an acute consumption of fat and protein Sasanow. J
Pediatr 1986
MAC:HC ratio
Fetal malnutrition and early metabolic risk
MAC:HC
Especially useful in diagnosing
malnourished AGA neonates
who would be not identified as
IUGR by the criterion exclusively
based on BW (still > 3rd centile)
Patterson. Am J Obstet Gynecol
1987
MAC:HC
Better indicator of early
metabolic risk and
Hypothermia than the PI
Chang. Early Hum Dev
1993
GA
(weeks)
MAC (cm) MAC:HC
Mean SD Mean SD
25-26 4.9 0.7 0.22 0.02
27 5.25 0.3 0.22 0.01
28 5.5 0.5 0.23 0.02
29 5.7 0.4 0.23 0.02
30 6.0 0.7 0.23 0.02
31 6.4 1.0 0.23 0.03
32 7.0 0.5 0.24 0.02
33 7.0 0.8 0.24 0.02
34 8.3 0.5 0.27 0.01
35 8.1 0.6 0.26 0.01
36 8.3 0.6 0.26 0.02
37 9.5 0.7 0.28 0.02
38 9.5 0.7 0.28 0.01
39 9.7 0.9 0.28 0.02
40 10.1 0.6 0.29 0.02
41 10.2 0.6 0.29 0.02
42 10.6 0.5 0.30 0.01
Sasanow. J Pediatr 1986
MAC:HC ratio
Fetal malnutrition and early metabolic risk
(Barker theory)
FETAL MALNUTRITION
Permanent intrauterine structural and functional changes
(“programming”)
Neonatal anthropometric indicators: fetal malnutrition
+
Postnatal anthropometric indicators: fast catch-up growth
Insulin resistance
Obesity, cardiovascular disease, hypertension, dyslipidemia,
diabetes 2
LATE METABOLIC SYNDROME
Late Metabolic Syndrome
Anthropometry at birth
WEIGHT
<1500g and <1000g risk of glucose intolerance and late metabolic
syndrome (MS) Barker. Diabetologia 1993, Pandolfi. Metabolism 2008
SGA and Macrosomy risk of late MS McCance. BMJ 1994, Wang.
Indian J Pediatr 2007
<2500g + fast catch-up growth 0-6 months Hypertension in adulthood
McCarthy. Pediatr Res 2001
SGA + fast catch-up growth 0-3 years insulin resistance + central
adiposity Soto. J Clin Endocrinol Metab 2003, Mericq. Diabetologia 2005
Late Metabolic Syndrome
Anthropometry at birth + Anthropometric evolution
Asymmetrical SGA +
Fast catch-up growth fast catch-up growth 0-2 anos BMI, central
adiposity and hypertension at age of 5-8 years Ong. BMJ 2000, Singhal,
Circulation 2006
Adiposity spurt (BMI) 7-15 years coronary disease in adulthood
Eriksson. BMJ 1999
Late Metabolic Syndrome
Anthropometry at birth + Anthropometric evolution
Term AGA neonates +
Fast weight gain 0-6 months (but not at 3-6 years) risk of
metabolic syndrome (waist circumference, blood pressure,
triglycerides, HDL, glicemia, insulinemia) at age of 17 years,
independently of BW Ekelund. J Clin Endocrinol Metab. 2007
Late Metabolic Syndrome
Anthropometry at birth + Anthropometric evolution
Mid-arm Cross Sectional Areas
Equations based on mid-arm circumference (MAC) and tricipital skinfold
(TS) estimate total arm area (AA), arm muscle area (AMA) and
arm fat area (AFA):
AA= MAC2 / 4; AMA = (MAC– TS) / 4; AFA= AA- AMA Jelliffee. J
Trop Pediatr 1969
AFA = MAC.TS/2; AMA = AA – AFA Rolland-Cachera. AJCN 1997
For the same mid-arm circumference (MAC):
Case 1 Case 2
Fat area 1 > Fat area 2 Muscle area 1 < Muscle area 2
Mid-arm Cross Sectional Areas
May be better indicators of the relative contribution of fat and muscle in total arm
area, than the isolated values of MAC and TS
Georgieff. J Pediatr 1989, Hediger. Pediatrics 1998
Correlation with body composition in:
In adults (CT scan). Heymsfield. Am J Clin Nutr 1982
In adolescents and children > 9 years (MRI). Rolland-Cachera. AJCN
1997
In neonates (DEXA). Koo. Pediatr Res 2004
Mid-arm Cross Sectional Areas
In neonates and small infants:
Reference values published. Sann. Arch Dis Child 1988
Frequently used in nutrition assessment. Georgieff. J Pediatr 1989,
Hediger. Arch Pediatr Adolesc Med. 1998
Mid-arm Cross Sectional Areas
In neonates and small infants:
Regional anthropometry (eg, mid-arm) as indicator of whole body
composition Consistency questioned: regional anthropometry
also will allow the estimate of the composition of the interested
region (eg, mid-arm)
Mid-arm Cross Sectional Areas
Anthropometry versus Ultrasound: term neonates
Mid-arm Cross Sectional Areas
Healthy term neonates:
Anthropometry
Poor correlation with the
ultrasound measures
Overestimate muscle area
muscular (±110%) and
underestimate fat area (±35%).
However, both methods have
limitations…
Pereira-da-Silva. Early Hum Dev 1999
Mid-arm Cross Sectional Areas
Anthropometriy versus MRI: preterm infants
Mid-arm Cross Sectional Areas
Preterm infants:
Anthropometry
Compared with magnetic
resonance measurements
Direct and derived measures –
non reliable predictors (r2<0.56) of
the mid-arm compartments
Pereira-da-Silva. Neonatology 2009
Mid-arm Cross Sectional Areas
Mid-arm Anthropometry
To summarize, neonates and small infants:
Simple, noninvasive, non expensive and convenient method
(bedside tool)
Useful in individual longitudinal measurements
Other measurements: interpret with caution
II. BIOCHEMICAL INDICATORS
Protein markers
1. Prealbumin
Neonate: term 4-20 mg/dl; preterm 4-14 mg/dl
Half-life ±24 h (albumin 14-20 days)
Limitations: in preterms hepatic synthesis and turnover
Polberger. Acta Paediatr Scand 1990 ; Anderson. Clin Perinatol 2002
2. Retinol binding protein
1-7,8 mg/dl
Half-life 12 h
Specific vitamin A binding proetin; circulates in plasma bound to
prealbumin
Limitations: affected by hepatic dysfunction, infections,
corticotherapy, renal diseases
Protein markers
3. BUN
7-22 mg/dl
It is not an indicator of protein reserve, however may reflect the
intake of protein (specially if insufficient)
Moro. J Pediatr Gastroenterol Nutr 1995
Protein markers
1. Blood markers
Hypophosphatemia (<4mg/dl), hypocalcemia and high alkaline
phosphatase (>800 IU/ml) – poor correlation with BMC
assessed by DEXA in preterm infants Faerk. ADC Fetal Neonatal
Ed 2002
Bone markers
2. Urine markers
Urinary excretion of Ca and P - Tubular rebsorption of phosphate
(TRP) - good guide for phosphate supplementation; if >95%
inadequate supplementation
%TRP = 1 − (PU/CrU) x (CrU/Pp) x 100
P = phosphorus; Cr = creatinine; U = urine; p = plasma
Harrison. Acta Paediatr 2008
Bone markers
3. Urine markers
Urinary Ca and P : creatinine ratios
Reference values: 95th centile: CaU:CrU = 3.8 mmol/mmol; PU:CrU =
26.7 mmol/mmol Aladangady. Pediatr Nephrol 2004
Standard reference - limited usefulness: ratios highly depend on
type of feed (HM, formula…) and not validated (DEXA) Harrison.
Acta Paediatr 2008
Bone markers
Hematological markers
Fe and folic acid hemogram, ferritin, transferrin
Growth Factors
Proteins binding to receptors of cell membranes activate
proliferation and differentiation
Depend on the nutritional status
Permit the evaluation of growth and nutritional status
Usually limited to research
Growth Factors
1. Insuline growth-like factor 1 (IGF-1)
1. Before known as somatomedin C
Released by the liver in response to the GH
Positive correlation with the gestational age and the energy
and protein intake
Kajantie. Pediatr Res 2001, Moyer-Mileur. Clin Perinatol 2007
Growth Factors
2. IGFBP-3
Main IGF-1 binding protein (among 6)
Allows a better interpretation of IGF-1 values
Kajantie. Pediatr Res 2001, Moyer-Mileur. Clin Perinatol 2007
Growth Factors
3. Leptin
Protein secreted by the adipocyte “signals” the brain on
energy reserve status
Positive correlation with : amount if stored fat, birth weight,
BMI, insulinemia andIGF-1
↓ leptinemia – undernourished preterm infants
Ng. Clin Endocrinol 2001, Moyer-Mileur. Clin Perinatol 2007
III. BODY COMPOSITION
Levels of Body Composition
5 Levels
Wang. AJCN 1992
Levels of Body Composition Neonate
Model of 2 or 3 levels: less informative, but more practical and feasible
Rigo. Nestle Nutr Workshop Ser Pediatr Program 2006
Body mass (weight) = Fat mass FM + Fat free mass FFM (+ Bone
mass)
Terminology
FFM = Lean mass + non-fat components of the adipose tissue
FM = pure fat
Adipose tissue = FM + cellular structures and non-cellular structures
of support
Body composition Noninvasive methods of assessment
more used
I. Magnetic resonance imaging (FM + FFM)
II. Dual energy x-ray absorptiometry (DEXA) (FM + FFM + bone mass)
III. Air displacement plethysmography (FM + FFM)
IV. Bioimpedance analysis (FM + FFM)
V. Anthropometry (FM + FFM)
VI. Others: total-body electrical conductivity (TOBEC), infrared
spectroscopy (FM + FFM) …
I. Magnetic resonance imaging
Gold standard in the measurement of adipose tissue (high precision,
fat volumetry), validated in preterm infants Olhager. Pediatr Res 1998,
Harrington. Lipids 2002
Limitations: very expensive, require motionless / sedation, and
displacement of the patient into the equipment Used for research
and validation of less accurate methods Rigo. Nestle Nutr Workshop Ser
2006
Regional assessment - “quality” of fat
Neonates ≤32 weeks
Normal evolution: postnatal
acceleration of growth total and
subcutaneous fat
Severe disease: deep intra-
abdominal fat risk of insulin
resistance
Uthaya. Pediatr Res 2005
I. Magnetic resonance imaging
II. Dual energy x-ray absorptiometry (DEXA)
3-compartment model: FM, FFM and bone mineral content
Good reproducibility in neonates and small infants Godand. J Clin
Densitom 2010
Rapid (6–10 min); non requiring sedation Rigo. Nestle Nutr Workshop
Ser 2006
Limitations:
Reliability questioned in small
individuals requiring validation
Lapillonne. Horm Res 1997, Koo. J Am Coll
Nutr 2004
Expensive, requires displacement of
the patient into the equipment Rigo.
Nestle Nutr Workshop Ser 2006
II. Dual energy x-ray absorptiometry (DEXA)
III. Air displacement plethysmography
(Pea Pod®)
2-compartment model: FM, FFM
Density = Mass/ Volume; %MG = (495/
density) - 450
Validated in neonates and small infants (1-
8 Kg) Ma. AJCN 2004
Advantages: Movable equipment; rapid (4-
5 min); movements allowed Rigo. Nestle
Nutr Workshop Ser 2006
Limitation: Expensive and does not
measure regional fat
Nutrition Lab, H. D. Estefânia
42 days of life,
weighing =1412 g
Enfalac AR® 14%
Miltina Prem® ( energy
and protein) thickened
121 136 Kcal/Kg/d
Prot 3 4,3 g/Kg/d
1 week later:
49 days of life,
weighing =1569 g
(+157 g)
III. Air displacement plethysmography
(Pea Pod®)
A.
Fat free mass
1364 g (96,6%)
Fat mass
47,8 g (3,4%)
B. 1 week later
Fat free mass
1569 g (91,8%)
Fat mass
141 g (8,2%)
III. Air displacement plethysmography
(Pea Pod®)
IV. Bioimpedance analysis
2-compartment model: FM, FFM
Portable equipment (tetrapolar),
allows movements, relatively
inexpensive, bedside use Rigo. Nestle
Nutr Workshop Ser 2006
Not validated in neonates and small
infants… Dung. Eur J Pediatr 2007
NICU, Hospital Dona Estefânia, Lisbon
V. Quantitative Ultrasound
Bone compartment
Convenient method: Noninvasive,
portable equipment , allows
movements, relatively inexpensive,
bedside use
Measures the bone strength; Unit of
measure : speed of sound (SOS) m.s-1
Littner. J Pediatr Endocrinol Metab 2003
NICU, Hospital Dona Estefânia, Lisbon
In neonates and small infants
Standardized method but not validated yet Littner. J Pediatr Endocrinol
Metab 2003
QUS cannot be used as a surrogate for DEXA; however, both
methods may complement each other in the assessment of bone
health Gianni. Arch Dis Child Fetal Neonatal Ed 2008
V. Quantitative Ultrasound
Bone compartment
I. Clinical indicators (Anthropometry)
Anthropometry – the most used method – however it is usually
limited to weight evolution…
Urgent validation of more measurements
Summary
Nutrition Assessment of the Neonate
II. Biochemical indicators
– Energy, protein and bone markers: several limitations,
especially in preterm infants
– Hematological markers – useful in clinical practice
– Growth factors – useful in research
Summary
Nutrition Assessment of the Neonate
III. Body composition
MRI: gold standard, volumetric measurements, used in research
and for validation of other methods
DEXA: 3-comparment model (+ BMC), good reliability, but validity
questioned in small individuals
ADP (Pea Pod): 2-comparment model, promising method, but
does not measure regional fat
Summary
Nutrition Assessment of the Neonate
III. Body composition
QUS: bone compartment (bone strength), promising method
Bioimpedance analysis: 2-comparment model, convenient,
relatively inexpensive, but not validated
Summary
Nutrition Assessment of the Neonate
Clinical practice, tools usually available in NICU
Daily weight; weekly: length and HC
BUN to monitor protein intake (weekly or every 2 wks)
Phosphatemia and alkaline phosphatase to monitor bone
nutrition (weekly or every 2 wks)
Hemogram and ferritin to monitor iron and folic acid intake
(every 2 wks)
Check long bones in x-rays
Suggestion
Thank you