Exclusive human milk feeding and prevalence of early adiposity rebound in ELBW infants: a retrospective cohort study

Abstract

The purpose of the present study was to evaluate the prevalence of early adiposity rebound (EAR) and factors associated with its occurrence in a cohort of extremely low birth weight infants (ELBW). We conducted a retrospective longitudinal study including ELBW infants followed-up for up to 10 years after discharge. EAR was defined as occurring before 5 years of age. A multivariate binary logistic regression analysis was performed to evaluate maternal and perinatal variables independently associated with EAR. Out of 212 ELBW infants included in the analysis, 40.6% developed EAR and 21.5% showed it before 4 years of age. Only formula milk feeding at discharge was independently associated with a higher risk of EAR. The mean BMI of children with EAR was higher than that of children without EAR. Furthermore, the prevalence of overweight and obesity was higher in the EAR group than in the timely AR group. Conclusions: ELBW infants in our cohort developed EAR in a relatively high percentage of cases. In this already at-risk population, EAR may represent a further risk factor for an adverse metabolic outcome. Monitoring preterm infants' growth within a long-term follow-up program and promoting and supporting human milk feeding is advisable. What is Known: • Preterm-born infants are at high risk for long-term adverse health outcomes, especially cardiovascular and metabolic. • The occurrence of early adiposity rebound (EAR) is associated with the risk of later obesity and metabolic syndrome. What is New: • The occurrence of EAR in ELBW infants may represent an additional risk factor for later adverse metabolic outcomes in an already vulnerable population. • Future preventive strategies should include a long-term follow-up and the promotion of exclusive breastfeeding.

Keywords: ELBW infants; Early adiposity rebound; Human milk; Metabolic outcomes.

Fig. 1

Flow-chart of the study

Fig. 2

Multiple line graph representation of weight, length/height, and BMI trajectories of the study population throughout the study period

Fig. 3

Mean BMI values in children with early adiposity rebound (EAR) and timely adiposity rebound (AR). **p < 0.001. C.I. 95% 5 years, − 1.3; − 0.4. C.I. 95% 6 years, − 1.9; − 0.9. C.I. 95% 7 years, − 2.2; − 1.0. C.I. 95% 8.5 years, − 2.8; − 1.1. C.I. 95% 10 years, − 4.6; − 1.9

Fig. 4

Estimated marginal means of BMI with standard errors at different time points showing the effect of EAR on BMI overtime. A Repeated Measures ANOVA showed a significant effect of EAR on BMI (F(2.03) = 5.53, p = 0.006, partial η2 = 0.15)