Early diet and peak bone mass: 20 year follow-up of a randomized trial of early diet in infants born preterm.
BACKGROUND
Preterm infants are at risk of metabolic bone disease due to inadequate mineral intake with unknown consequences for later bone health.


OBJECTIVE
To test the hypotheses that (1) early diet programs peak bone mass and bone turnover; (2) human milk has a beneficial effect on these outcomes; (3) preterm subjects have reduced peak bone mass compared to population reference data.


METHODS
20 year follow-up of 202 subjects (43% male; 24% of survivors) who were born preterm and randomized to: (i) preterm formula versus banked breast milk or (ii) preterm versus term formula; as sole diet or supplement to maternal milk. Outcome measures were (i) anthropometry; (ii) hip, lumbar spine (LS) and whole body (WB) bone mineral content (BMC) and bone area (BA) measured using DXA; (iii) bone turnover markers.


RESULTS
Infant dietary randomization group did not influence peak bone mass or turnover. The proportion of human milk in the diet was significantly positively associated with WBBA and BMC. Subjects receiving >90% human milk had significantly higher WBBA (by 3.5%, p=0.01) and BMC (by 4.8%, p=0.03) than those receiving <10%. Compared to population data, subjects had significantly lower height SDS (-0.41 (SD 1.05)), higher BMI SDS (0.31 (1.33)) and lower LSBMD SDS (-0.29 (1.16)); height and bone mass deficits were greatest in those born SGA with birthweight <1250 g (height SDS -0.81 (0.95), LSBMD SDS -0.61 (1.3)).


CONCLUSIONS
Infant dietary randomization group did not affect peak bone mass or turnover suggesting the observed reduced final height and LS bone mass, most marked in growth restricted subjects with the lowest birthweight, may not be related to sub-optimal early nutrition. The higher WB bone mass associated with human milk intake, despite its low nutrient content, may reflect non-nutritive factors in breast milk. These findings may have implications for later osteoporosis risk and require further investigation.
Fewtrell
Mary S
MS
MRC Childhood Nutrition Research Centre, UCL Institute of Child Health, London, UK. m.fewtrell@ich.ucl.ac.uk
Williams
Jane E
JE
Singhal
Atul
A
Murgatroyd
Peter R
PR
Fuller
Nigel
N
Lucas
Alan
A
D000328:Adult; D000886:Anthropometry; D015415:Biomarkers / Q000378:metabolism; D001724:Birth Weight; D001827:Body Height; D015992:Body Mass Index; D015519:Bone Density; D016723:Bone Remodeling; D001842:Bone and Bones / Q000033:anatomy & histology*; D002118:Calcium / Q000378:metabolism; D004032:Diet; D005260:Female; D005500:Follow-Up Studies; D050723:Fractures, Bone / Q000503:physiopathology; D006262:Health; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000254:growth & development*; D008297:Male; D008895:Milk, Human; D009929:Organ Size; D047928:Premature Birth / Q000503:physiopathology*
D015415:Biomarkers; D002118:Calcium