Improved child development outcomes in rural Uganda: long-term follow-up of a randomized maternal education trial

Abstract

Background: Uganda, being a low-and-middle income country, struggles with high stunting (low height-for-age) rates which may result in impaired child development. Although there are several causative factors of child stunting and inadequate development, low nutrient supply, poor hygiene and lack of stimulation, are main promoters. In addition, a dysregulated gut microbiota, inadequate iodine status and maternal depression may play a role. Up until 2013, few if any maternal education intervention studies had been conducted within the framework of a community-based randomized controlled trial (RCT), and long-term follow up studies were not performed. We therefore conducted a cluster-RCT in 2013-14 comprising a six months’ maternal education intervention primarily to reduce child stunting. The study included 511 mother-child pairs and started when the children were 6-8 months. Whereas we found no effects on growth when the children were 20-24 months, several developmental outcomes were markedly improved in the intervention group compared to the controls. Aims: Given these promising data on developmental outcomes we performed a follow-up study when the children were 20-24 and 36 months (current thesis). In addition to assessments of developmental outcomes and growth, we investigated child gut microbiota, iodine status and maternal depression symptoms. Methods: The maternal education in the original trial focused on nutrition, hygiene and stimulation. Anthropometry was measured using WHO-standards whereas development outcomes were assessed with three independent neuropsychological tools. We used 16S rRNA gene sequencing to study gut bacteria whereas a colorimetric method was used to determine urine iodide concentration (a marker of iodine intake). Maternal depression symptoms were self-reported. Results: The intervention significantly improved child development outcomes at 20-24 and at 36 months. Linear growth faltering was significantly less at 36 months in the intervention compared with the control group. The intervention did not lead to any significant changes in gut microbiota or iodine intake, but iodine intake was associated with child cognitive scores. The intervention reduced maternal depression symptoms and this reduction was associated with improved child cognitive- and language development. Conclusion: Our maternal education intervention had long-lasting positive effects on child development and perhaps linear growth. Possible explanations for these findings include adequate iodine intake and reduced maternal depression while gut microbiota was not affected by the intervention. To identify the mechanism(s) underlying the detrimental effects of child undernutrition on growth and development requires multiple approaches including mechanistic studies and well-conducted community-based RCTs.