Supplementation with vitamin A early in life and subsequent risk of asthma
European Respiratory Journal
Asthma; Longitudinal study; Randomised clinical trial; Vitamin A
Animal models suggest that vitamin A deficiency affects lung development adversely and promotes airway hyperresponsiveness, and may predispose to an increased risk of asthma. We examined the long-term effects of vitamin A supplementation early in life on later asthma risk. In 2006-2008, we revisited participants from two cohorts in rural Nepal who were enrolled in randomised trials of vitamin A supplementation. The first cohort received vitamin A or placebo for <16 months during their pre-school years (1989-1991). The second cohort was born to mothers who received vitamin A, β-carotene or placebo before, during and after pregnancy (1994-1997). At follow-up, we asked about asthma symptoms and performed spirometry. Out of 6,421 subjects eligible to participate, 5,430 (85%) responded to our respiratory survey. Wheezing prevalence during the previous year was 4.8% in participants aged 9-13 yrs and 6.6% in participants aged 14-23 yrs. We found no differences between the vitamin A supplemented and placebo groups from either trial in the prevalence of lifetime or current asthma and wheeze or in spirometric indices of obstruction (p≥0.12 for all comparisons). Vitamin A supplementation early in life was not associated with a decreased risk of asthma in an area with chronic vitamin A deficiency. Copyright©ERS 2011.
Checkley, W., West, K., Wise, R., Wu, L., LeClerq, S., Khatry, S., Katz, J., Christian, P., Tielsch, J., & Sommer, A. (2011). Supplementation with vitamin A early in life and subsequent risk of asthma. European Respiratory Journal, 38 (6). http://dx.doi.org/10.1183/09031936.00006911