Two community-based trials in neighboring health districts of Burkina Faso found that small-quantity lipid-based nutrient supplements increased child growth, but zinc supplementation had no effect, compared with non-intervention cohorts. We aimed to explore whether differential growth effects are associated with differences in intervention, demographic variables, or morbidity between studies.
Children in the LNS study received 20g SQ-LNS daily containing different amounts of zinc (LNS). Children in the zinc supplementation study received different zinc supplementation regimens (ZS). Anthropometric measurements were repeated every 13-16 weeks (child-interval). Children were visited weekly for morbidity surveillance and received free malaria and diarrhea treatment. For the present analyses, child-intervals were matched by age and season of enrollment. The changes in height-for-age z-score (HAZ) per interval were compared for LNS and ZS using mixed model ANOVA or ANCOVA. Covariates were added to the model in groups, and adjusted differences between group means were estimated.
Mean ages at enrollment of LNS (n=1716) and ZS (n=1720) were 9.4±0.4 and 10.1±2.7 months, respectively. The age-adjusted change in HAZ per interval declined less with LNS -0.070±0.437 versus ZS -0.208±0.431 (p<0.0001). There was a significant group*interval interaction with the greatest difference found in 9-12 month old children (p<0.0001). Controlling for demographic characteristics and morbidity did not reduce the observed differences, even though the morbidity burden was greater in the LNS group.
Growth was greater in children who received LNS and could not be explained by known baseline characteristics or morbidity burden, implying that some of the difference in growth response was due to LNS.Funding: the Bill & Melinda Gates Foundation, Thrasher Research Fund, Canadian International Development Agency.