Plasma retinol level, vitamin A supplementation and acute respiratory infections in children of 1–5 years old in a developing country

Abstract

Study objective: To evaluate the relationship between vitamin A supplementation, plasma retinol level (PRL) and incidence, severity and duration of acute respiratory infections (ARI) in children 1–5 years old. Design and setting: A one year prospective randomized intervention study from June 1989 to May 1990 in Cikutra, a suburb of Bandung, Indonesia. Subjects and measurements: Out of almost 2000 children aged 12–54 months, 269 were selected by stratified randomization. Vitamin A (200 000 IU orally) was administered at 6-monthly intervals in a double blind, placebo controlled programme. Every 2 weeks, primary health care workers collected data on respiratory symptoms in the children, and every month a pediatrician examined the children. Venous blood samples were obtained at the start and at 3 and 6 months for plasma retinol levels (PRL). Results: The mean PRL at the start of the study was 20 ± 8 μg/dl; 8% of the children showed a deficient level of less than 10 μg/dl. The incidence of ARI was 6.7 ± 3.5 episodes per child per year, with a mean duration of 5.3 ± 3.1 days per episode. In vitamin A supplemented children the duration of ARI was slightly shorter (5.2 ± 3.1 versus 5.6 ± 3.1 days, P < 0.01) but no effect on the incidence or severity of ARI was detected. Low, and especially deficient, PRL had improved after 3 months and even more after 6 months, but this was unrelated to vitamin A supplementation. There was also no relationship between PRL and incidence, severity or duration of ARI. Conclusions: Only a slight relationship is found between vitamin A supplementation and ARI duration in under-fives.