Catch-up growth in the first two years of life in Extremely Low Birth Weight (ELBW) infants is associated with lower body fat in young adolescence

PLoS One. 2017 Mar 9;12(3):e0173349. doi: 10.1371/journal.pone.0173349. eCollection 2017.

Abstract

Aim: To investigate growth patterns and anthropometrics in former extremely low birth weight (ELBW, <1000 g) children and link these outcomes to neurocognition and body composition in childhood.

Methods: ELBW children were examined at birth (n = 140), at 9 and 24 months (n≥96) and at approximately 11 years within the framework of the PREMATCH (PREMATurity as predictor children's of Cardiovascular and renal Health) case-control (n = 93-87) study. Regional growth charts were used to convert anthropometrics into Z-scores. Catch-up growth in the first two years of life was qualified as present if ΔZ-score >0.67 SDS. At 11 years, anthropometrics, neurocognitive performance, body composition, grip strength and puberty scores were assessed.

Results: ELBW neonates displayed extra-uterine growth restriction with mean Z-scores for height, weight and head circumference of -0.77, -0.93 and -0.46 at birth, -1.61, -1.67 and -0.72 at 9 months, -1.22, -1.61 and -0.84 at 24 months, and -0.42, -0.49 and -1.09 at 11 years. ELBW children performed consistently worse on neurocognitive testing with an average intelligence quotient equivalent at 11 years of 92.5 (SD 13.1). Catch-up growth was not associated with neurocognitive performance. Compared to controls, ELBW cases had lower grip strength (13.6 vs. 15.9 kg) and percentage lean body weight (75.1 vs. 80.5%), but higher body fat (24.6 vs. 19.2%) and advanced puberty scores at 11 years (all P≤0.025). Catch-up growth for weight and height in the first two years of life in cases was associated with a lower percentage body fat compared to cases without catch-up growth (16.8% catch-up growth for weight vs. 25.7%, P<0.001; 20.9% catch-up for height vs. 25.8%, P = 0.049).

Conclusions: In young adolescence, former ELBW children still have difficulties to reach their target height. Compared to normal birth weight controls, ELBW adolescents show lower neurocognitive performance and grip strength and a higher percentage body fat, a potential risk factor for adverse health outcomes in adulthood. Our key finding is that catch-up growth in ELBW children in the first two years of life is associated with a lower percentage body fat and is therefore likely to be beneficial.

MeSH terms

  • Adipose Tissue / metabolism*
  • Adolescent
  • Body Composition
  • Body Height
  • Body Weight
  • Cognition
  • Female
  • Humans
  • Infant, Extremely Low Birth Weight / growth & development*
  • Infant, Extremely Low Birth Weight / physiology
  • Infant, Newborn
  • Male

Grant support

This study was supported by the “Agency for Innovation by Science and Technology in Flanders (IWT)” through the ‘SAFE-PEDRUG’ project (IWT/SBO 130033). K.A. and E.L. are senior clinical investigators of the Fund for Scientific Research, Flanders (Fundamental Clinical Investigatorship, 1800214N and 1801110N) and E.L. is also supported by the EURenOmics consortium (grant agreement 305608). The European Union (HEALTH-FP7-278249-EU-MASCARA, HEALTH-F7-305507 HOMAGE and the European Research Council Advanced Researcher Grant-2011-294713-EXPLORE) and the Fund for Scientific Research Flanders (G.0881.13 and G.088013) currently support the Studies Coordinating Centre in Leuven. J.A.S. is affiliated to R&D Group VitaK, part of Maastricht University, J.A.S. is not funded in any way by this affiliation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.