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

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.