Quarterly supplementation with vitamin D3 showed no reduction in time to first illness or on the risk for recurrent diarrheal disease. Consequently the researchers at the London School of Hygiene and Tropical Medicine concluded: “Similar supplementation to comparable populations is not recommended.”
Investigation into vitamin D as an additional micronutrient with possible preventative benefits in childhood diarrheal diseases stems from its immunologic properties.
The double-blind placebo-controlled trial looked at children aged 1 to 29 months living in a low income, inner city area in Kabul, Afghanistan.
These 3046 participants - targeted as a high risk population - were split between a placebo control group and an intervention group which received quarterly supplementation of 100 000 IU of vitamin D3.
Data on diarrheal episodes was gathered through active and passive surveillance over 18 months of follow-up.
The results, published in the journal Pediatrics, demonstrated no significant difference in survival time to first diarrheal illness. Incidences of diarrheal episodes were 3.43 per child-year in the placebo group and 3.59 in the intervention group.
Vitamin D3 supplementation was found to have no effect on the risk for recurrent diarrheal disease in either intention-to-treat or per-protocol analyses. It also remained ineffective in prevention when the randomised population was stratified by age groups, nutritional status, and seasons.
While the researchers concluded that they would not recommend this treatment for comparable populations, they advised that additional research in alternative settings could be useful in clarifying the role of vitamin D3 supplementation for prevention of diarrheal diseases.
1.8 million deaths annually
There are 2.5bn cases of diarrheal illnesses in children aged 5 globally, resulting in 1.8m deaths annually.
Recurrent enteric (gastrointestinal) illnesses can lead to malnutrition, disability and mortality among children.
“To combat diarrheal illnesses the World Health Organization recommends improved child nutrition and micronutrient supplementation. Zinc and vitamin A have been shown to reduce the incidence of diarrheal illnesses,” wrote the researchers.
Published online ahead of print, doi: 10.1542/peds.2012-3986
“Vitamin D3 Supplementation and Childhood Diarrhea: A Randomized Controlled Trial”
Authors: A. R. Aluisio, Z. Maroof, D. Chandramohan, J. Bruce, Z. Mughal, Z. Bhutta, G. Walraven, M. I. Masher, J. H. J. Ensink, and S. Manaseki-Holland