Latest AJCN Supplement
Small-quantity lipid-based nutrient supplements have been designed and marketed to improve child health, growth, and development, particularly among vulnerable populations. The American Journal of Clinical Nutrition’s (AJCN) latest Supplement, “Small-Quantity Lipid-Based Nutrient Supplements for Prevention of Malnutrition and Promotion of Healthy Development: Who Benefits Most?” explores not only whether these supplements work but, more specifically, who benefits the most from these supplements. This AJCN Supplement was sponsored by the Institute for Global Nutrition at the University of California, Davis, with funding from the Bill and Melinda Gates Foundation.
In the Editorial introducing the Supplement, “What Works and for Whom? Individual Patient Data Meta-Analyses in Global Nutrition Research,” ASN members Christopher R. Sudfeld and Emily R. Smith explain how each of the four reviews in this Supplement applied individual patient data meta-analyses to achieve “the most robust approach to answer questions about who benefits from interventions.” In particular, the authors underscore “individual patient data meta-analyses of child small-quantity lipid-based nutrient supplements published in this Supplement identified several effect modifiers that would not have been identifiable in study-level analyses.”
- Small-Quantity Lipid-Based Nutrient Supplements for the Prevention of Child Malnutrition and Promotion of Healthy Development: Overview of Individual Participant Data Meta-analysis and Programmatic Implications
Meta-analyses have demonstrated the benefits of small-quantity lipid-based nutrient supplements on child growth, anemia, and mortality. To further examine the efficacy and effectiveness of these supplements, ASN member Kathryn G. Dewey et al. conducted individual participant data meta-analyses of 14 randomized controlled trials involving more than 37,000 children aged 6 to 24 months. The authors found the benefits of the supplements were constant regardless of most study-level characteristics such as region, sanitation, and water quality. However, the benefits of the supplements on child development were greater among populations with higher stunting burden, households with lower socioeconomic status, and acutely malnourished children. Likewise, the supplements provided greater benefits for hemoglobin and iron status among populations with higher anemia prevalence and acutely malnourished children. The authors concluded, “targeting based on potential to benefit may be worthwhile for those outcomes.”
- Characteristics That Modify the Effect of Small-Quantity Lipid-Based Nutrient Supplementation on Child Growth: An Individual Participant Data Meta-analysis of Randomized Controlled Trials
Working with the same 14 randomized controlled trials discussed above, ASN member Kathryn G. Dewey et al. conducted a two-stage meta-analysis, with the goal of identifying study- and individual-level characteristics that modified the effect of small-quantity lipid-based nutrient supplements on child growth outcomes. Among the study findings, the authors noted that girls benefited more from the supplements than boys. For example, “among girls, small-quantity lipid-based nutrient supplements reduced stunting by 16%, wasting by 21%, low midupper arm circumference by 27%, and small head size by 15%, whereas the corresponding reductions among boys were 9%, 10%, 7%, and 4%, respectively.” Underlying this difference in outcomes, the authors pointed to studies suggesting that “boys are more vulnerable than girls to adverse conditions in early life, which may be driven by biological factors that could also constrain responses to nutrition interventions.” Interestingly, the authors found the supplement provided greater benefits to later-born children (as opposed to firstborns), suggesting that “there may be greater potential to benefit among later-born children in some settings.”
- Small-Quantity Lipid-Based Nutrient Supplements for Children Age 6–24 Months: A Systematic Review and Individual Participant Data Meta-Analysis of Effects on Developmental Outcomes and Effect Modifiers
ASN member Elizabeth L. Prado et al. sought to generate pooled estimates of the effect of small-quantity lipid-based nutrient supplements on brain developmental outcomes such as language, social-emotional, motor, and executive function, analyzing data from more than 30,000 children aged 6 to 24 months. In addition, the authors wanted to identify study- and individual-level characteristics that modified these effects. Overall, the authors found that the supplements “can be expected to result in modest developmental gains, which would be analogous to 1-1.5 IQ points.” The effects of supplements on language, social-emotional, and motor outcomes, however, were larger among study populations with a higher stunting burden, suggesting that policy-makers and program planners “can expect modest, but potentially important, developmental gains among children in the population, particularly in areas with high child stunting burden.”
- Characteristics That Modify the Effect of Small-Quantity Lipid-Based Nutrient Supplementation on Child Anemia and Micronutrient Status: An Individual Participant Data Meta-analysis of Randomized Controlled Trials
This review aimed to identify study- and individual-level characteristics that modified the effect of small-quantity lipid-based nutrient supplements on child hemoglobin, anemia, and inflammation-adjusted micronutrient status outcomes. To conduct their research, ASN member K. Ryan Wessells et al. conducted a two-stage meta-analysis of individual participant data culled from 13 randomized controlled trials involving 15,946 children aged 6-24 months. According to the study findings, at the study level, the beneficial effects of the supplements on hemoglobin “appeared to be greater among studies that were conducted in countries with a high burden of anemia (>60%).” At the individual level, the authors observed that the supplements had “a larger effect on both hemoglobin and ferritin concentrations among later-born than among first-born children, and reduced the prevalence of anemia in these subgroups by 12 and 7 percentage points, respectively.”
We invite you to peruse the complete Supplement to learn not only about the benefits of small-quantity lipid-based nutrient supplements, but also how individual participant data meta-analysis can help us better target nutritional interventions to individuals and specific populations.