Impact of vitamin A supplementation on prevalence and incidence of xerophthalmia in Nepal

Abstract

Purpose: To assess the impact of vitamin A supplementation at 4-month intervals on the prevalence and incidence of xerophthalmia among preschool-age children.

Methods: A stratified, random sample of 40 wards with 4766 children in Sarlahi district of Nepal was selected to participate in a randomized, controlled, community trial. In the vitamin A group, at 4-month intervals, neonates received 50,000 IU, 1- to 11-month-old infants received 100,000 IU, and children 1 through 4 years of age received 200,000 IU. Children underwent eye examination before the intervention and 16 months later.

Results: Before the intervention, 4318 children were examined for xerophthalmia. The prevalence was 2.3% in the vitamin A group and 3.3% in the placebo group. All children with xerophthalmia were treated with vitamin A at the time of the examination. Of those examined at baseline, 38 in the vitamin A group and 48 in the placebo group died in the 16 months after intervention. There were 1871 (84%) surviving children in the vitamin A group and 1711 (85%) in the placebo group examined at follow-up. After adjustment for the baseline prevalence of xerophthalmia, vitamin A reduced the prevalence at follow-up by 63% (95% confidence interval, 21% to 83%). The apparent incidence was 3.2/1000 per year in the vitamin A group and 9.2/1000 per year in the placebo group, an adjusted reduction of 62% (95% confidence interval, 0% to 86%).

Conclusions: Supplementation was effective at reducing the prevalence and incidence of xerophthalmia.