Objective: To assess the impact of vitamin A supplementation on morbidity from acute respiratory tract infections and diarrhoea.
Design: Double blind randomised placebo controlled field trial.
Setting: An urban slum area in New Delhi, India.
Subjects: 900 children aged 12-60 months attending a local health facility for acute diarrhoea of less than seven days' duration randomly allocated to receive vitamin A 200,000 IU or placebo.
Main outcome measures: Incidence and prevalence of acute lower respiratory tract infections and diarrhoea during the 90 days after termination of the enrolment diarrhoeal episode measured by twice weekly household surveillance.
Results: The incidence (relative risk 1.07; 95% confidence interval 0.92 to 1.26) and average number of days spent with acute lower respiratory tract infections were similar in the vitamin A supplementation and placebo groups. Among children aged 23 months or less there was a significant reduction in the incidence of measles (relative risk 0.06; 95% confidence interval 0.01 to 0.48). The incidence of diarrhoea was also similar (relative risk 0.95; 0.86 to 1.05) in the two groups. There was a 36% reduction in the mean daily prevalence of diarrhoea associated with fever in the vitamin A supplemented children older than 23 months.
Conclusions: Results were consistent with a lack of impact on acute lower respiratory tract related mortality after vitamin A supplementation noted in other trials and a possible reduction in the severity of diarrhoea.
PIP: Clinical vitamin A deficiency as manifested by mild xerophthalmia predisposes to increased diarrhea and respiratory morbidity. The authors therefore used a double blind randomized placebo controlled field trial to assess the impact of vitamin A supplementation in an urban slum of New Delhi, India, on morbidity from acute respiratory tract infections and diarrhea during a three-month period. 900 children aged 12-60 months attending a local health facility for acute diarrhea of less than seven days duration were randomly allocated to receive either vitamin A 200,000 IU or a placebo. The study found the incidence and average number of days with acute lower respiratory tract infections to be similar in both the supplementation and placebo groups. The incidence of measles among those aged 23 months or less, however, was reduced significantly in the supplementation group. The incidence of diarrhea was also similar in the two groups, although there was a 36% reduction in the mean daily prevalence of diarrhea associated with fever in the vitamin A supplemented children older than 23 months. The lack of impact upon acute lower respiratory tract related mortality after vitamin A supplementation has been seen in other trials.