Routine vitamin A supplementation for the prevention of blindness due to measles infection in children

Abstract

Background: Reduced vitamin A concentration increases the risk of blindness in children infected with the measles virus. Promoting vitamin A supplementation in children with measles contributes to the control of blindness in children, which is a high priority within the World Health Organization (WHO) VISION 2020 The Right to Sight Program.

Objectives: To assess the efficacy of vitamin A in preventing blindness in children with measles without prior clinical features of vitamin A deficiency.

Search strategy: We searched CENTRAL (2011, issue 1), which includes the Cochrane Acute Respiratory Infections Group Specialised Register, MEDLINE (1950 to January 2011), EMBASE.com (1974 to January 2011) and LILACS (1985 to January 2011).

Selection criteria: Randomised controlled trials (RCTs) assessing the efficacy of vitamin A in preventing blindness in well-nourished children diagnosed with measles but with no prior clinical features of vitamin A deficiency.

Data collection and analysis: Two review authors independently searched the results for eligible studies and extracted data on reported outcomes. We contacted trial authors of the included studies for additional information on unpublished data. We included two RCTs which were clinically heterogenous. We presented the continuous outcomes reported as the mean difference (MD) with 95% confidence interval (CI). Due to marked clinical heterogeneity we considered it inappropriate to perform a meta-analysis.

Main results: Two RCTs involving 260 children with measles which compared vitamin A with placebo met the inclusion criteria. Neither study reported blindness or other ocular morbidities as end points. One trial of moderate quality suggested evidence of a significant increase in serum retinol levels in the vitamin A group one week after two doses of vitamin A (MD 9.45 µg/dL; 95% CI 2.19 to 16.71, 17 participants) but not six weeks after three doses of vitamin A (MD 2.56 µg/dL; 95% CI -5.28 to 10.40; 39 participants). There was no significant difference in weight gain six weeks (MD 0.39 kg; -0.04 to 0.82; 48 participants) and six months (MD 0.52 kg; 95% CI -0.08 to 1.12; 36 participants) after three doses of vitamin A. The second trial found no significant difference in serum retinol levels two weeks after a single dose of vitamin A (MD 2.67 µg/dL; 95% CI -0.29 to 5.63, 155 participants).

Authors' conclusions: We did not find any trials assessing whether or not vitamin A supplementation in children with measles prevents blindness. However, vitamin A use in children should be encouraged for its proven clinical benefits.