Infant gut microbiota characteristics generally do not modify effects of lipid-based nutrient supplementation on growth or inflammation: secondary analysis of a randomized controlled trial in Malawi

Authors: HUGHES, RILEY - University Of California, Davis; ARNOLD, CHARLES - University Of California, Davis; YOUNG, REBECCA - Duke University; ASHORN, PER - Tampere University Hospital; MALETA, KEN - University Of Malawi; FAN, YUE-MEI - Tampere University Hospital; ASHORN, ULLA - Tampere University Hospital; CHAIMA, DAVID - University Of Malawi; MALAMBA-BANDA, CHIKONDI - University Of Malawi; Kable, Mary; DEWEY, KATHRYN - University Of California, Davis

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/21/2020
Publication Date: 9/9/2020
Citation: Hughes, R.L., Arnold, C.D., Young, R., Ashorn, P., Maleta, K., Fan, Y., Ashorn, U., Chaima, D., Malamba-Banda, C., Kable, M.E., Dewey, K.G. 2020. Infant gut microbiota characteristics generally do not modify effects of lipid-based nutrient supplementation on growth or inflammation: secondary analysis of a randomized controlled trial in Malawi. Scientific Reports. https://doi.org/10.1038/s41598-020-71922-x.
DOI: https://doi.org/10.1038/s41598-020-71922-x

Interpretive Summary: It has been proposed that the bacteria within the infant gut can affect the benefit that infants receive from diet and nutritional supplements. This is a particularly important idea to explore when considering nutritional supplements for malnourished infant populations. Therefore, we examined the gut bacterial communities of Malawian infants before (6 months of age) and after (12 and 18 months of age) provision of a small quantity lipid supplement. Specific hypotheses that have previously been presented from more exploratory data analyses were tested regarding the potential influence of specific bacteria on the outcome (infant growth and inflammation) of a lipid based supplement. Although we found no conclusive evidence that the bacteria within the infant gut can modify the effect of a small quantity lipid based supplement, we did observe trends for Clostridium and Ruminococcus to be associated with improved growth response to the supplement while Faecalibacterium was associated with higher inflammation response to the supplement. These bacterial types are worth exploring further in conjunction with infant response to lipid based supplements.

Technical Abstract: Efforts to improve infant growth by reducing nutrient deficiencies in undernourished populations are not always successful. It is possible that an unhealthy baseline gut microbial community may act as a barrier to improvement in growth and health outcomes in response to nutritional interventions. The objective of this analysis was to determine whether the infant microbiota at 6 months modified the effect of a nutritional intervention utilizing small-quantity lipid-based nutrient supplements (SQ-LNS) on growth or inflammation outcomes at 12 and 18 months, respectively. Fecal samples at 6 months of age (prior to infant supplementation) were used to characterize baseline microbiota composition using 16S rRNA gene sequencing of the V4 region. Features of the gut microbiota previously identified as being involved in metabolism of fatty acids or micronutrients or involved in outcomes relating to growth and inflammation, especially in children, were investigated. After correction for multiple hypothesis testing, no significant effect modification by the gut microbiota of SQ-LNS supplementation on infant growth and inflammation outcomes was found in the current cohort. Future studies should investigate the presence or absence of effect modification in the context of different nutritional interventions and outcomes to provide further insight.