Effect of vitamin A supplementation and the role of infections and inflammation on vitamin A status in children aged 36–59 months in rural Burkina Faso: results of a community-based pre-post intervention study

BACKGROUND: Several interventions are implemented in Burkina Faso to tackle vitamin A (VA) deficiency. This study assessed the effects of high-dose VA supplementation (VAS) on indicators of VA status in preschool children and examined whether infections and inflammation modified VA status post-supplementation. METHODS: A community-based pre-post intervention study was conducted during the dry season in rural Burkina Faso among 60 children aged 36–59 months. After baseline assessment, each child received a high-dose oral VAS, and an endline assessment was performed one month later. VA total body stores (TBS), total liver reserve (TLR), and serum retinol concentrations were assessed. Effects of VAS were assessed using Student’s t-test for mean differences across time points (pre- and post-supplementation) and McNemar’s test for differences in proportions. Inflammation was defined as elevated concentrations of C-reactive protein (CRP) or α-1-acid glycoprotein (AGP) at any measurement point (Day 0 or Day 14, pre- or post-supplementation). Malaria infection was assessed at Day 0 during both study phases, and intestinal parasites were evaluated at baseline. Linear regression was used to test the modifying effects of infections and inflammation on VA status post-supplementation. RESULTS: Neither unadjusted nor adjusted serum retinol concentrations changed significantly following high-dose VAS. Although geometric mean ratios (GMRs) suggested modest, non-significant changes in VA TBS and TLR, the prevalence of hypervitaminosis A (TLR ≥ 1 µmol/g) significantly increased from 17% to 38% post-supplementation. Infections and inflammation did not significantly modify changes in VA status overall. However, the GMR for retinol at endline compared to baseline was 0.68 (95%CI: 0.51; 0.91) among children with elevated CRP, corresponding to a 32% reduction in retinol levels (p = 0.011). CONCLUSIONS: High-dose VAS resulted in limited effects on VA status among children whose baseline VA status was already adequate, as indicated by TBS and TLR. Infections and inflammation had minimal to no influence on VA indicators post-supplementation. Future studies should include larger samples and use comprehensive assessment tools to assess the full spectrum of VA status, from deficiency to hypervitaminosis, while accounting for a broader spectrum of infection risks. Such approaches will help better evaluate VA intervention strategies within the context of overlapping public health programs. TRIAL REGISTRATION: Retrospective study registration as a clinical trial was done with the Pan African Clinical Trials Registry (Cochrane South Africa; PACTR201803002999356) on 22 March 2018.