Leptin and IGF‐1 in relation to body composition and bone mineralization of preterm‐born children from infancy to 8 years

Abstract

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. Funding informationThe original randomized controlled trial was supported by an unrestricted research grant from Friesland Campina, Amersfoort, the Netherlands. Friesland Campina also provided the formulas. CR was supported by an unrestricted research grant, provided by Hero Benelux, Breda, the Netherlands. Neither Friesland Campina nor Hero Benelux had a role in the design and execution of the studies, or in the analysis and interpretation of the results. SummaryObjective: Preterm birth has been associated with altered body composition, especially increased fat mass (FM) and decreased bone mineralization, and leptin and IGF-1 have been suggested to be involved in the regulation of both. We aimed to study the interplay between leptin, IGF-1, FM and bone mineralization measured in infancy and childhood of children born preterm. Design: Observational study.Patients/subjects: Seventy-nine (40 boys) preterm-born children (gestational age ≤32 weeks and/or birth weight ≤1500 g) aged 8 years.Measurements: Serum leptin and IGF-1 were measured at term age, at 3-and 6-month corrected age (CA), and 8 years. Body composition (fat and lean mass) and bone parameters (bone area, mineral content and density) were measured by Dualenergy X-ray Absorptiometry (DXA) at term age, 6-month CA and 8 years.Results: Leptin was positively associated with FM at all time points and with bone parameters at term age and 6-month CA. IGF-1 was associated with body composition and bone density at most of the time points. Explained variation in bone mineralization increased significantly by adding bone area (BA) and height to the models. Conclusions:During infancy and childhood, leptin and IGF-1 were associated with body composition in preterm-born children. In addition, leptin was associated with bone parameters in early infancy, but not in childhood. It is hypothesized that a complicated interplay between multiple pathways, which most likely changes over time, is involved in regulation of body composition and bone mineralization of pretermborn infants. K E Y W O R D Sbone mineralization, fat mass, follow-up, IGF-1, leptin, preterm infants

IGF-I, Growth, and Body Composition in Preterm Infants up to Term Equivalent Age

“…Nevertheless, given the sample size and observational nature of this study, the evidence for this hypothesis is inconclusive and remains speculative. Moreover, this is in contrast to reports by Ruys and colleagues who found a positive association between IGF-I and fat free mass as well as fat mass measured in preterm infants at term equivalent age, implying that IGF-I relates to overall growth rather than body composition [ 11 ]. However, in relation to later measurements of body composition, others did find IGF-I to relate to body composition.…”

Metabolic Hormone Profiles in Breast Milk From Mothers of Moderate-Late Preterm Infants Are Associated With Growth From Birth to 4 Months in a Sex-Specific Manner

“…Higher MOM IGF-1 concentrations at 4 months' corrected age were instead associated with a greater waist circumference. Previous studies around circulating IGF-1 during infancy confirm the relationship between IGF-1 and leptin concentrations and the association of both these compounds with infant fat and, to a lesser extent, lean mass (60)(61)(62). Previous studies have reported on a strong correlation between waist circumference and fat mass (63) although in our cohort IGF-1 did not show any association with fat mass.…”

Pre- and Post-Pubertal Leptin Levels in Subjects Born Very Preterm and Full-Term Small for Gestational Age in Relation to Measurements of Adipose Tissue

“…The robust correlation between IGF-I and adipose tissue in VPT-LBW men indicate that IGF-I might be of special importance in this group. During infancy and childhood, up to 8 years, leptin but also in some extent IGF-I positively correlated with fat mass in PT-LBW 39 .…”