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Vitamin E and respiratory tract infections in elderly persons.

To the Editor: Dr Meydani and colleagues reported the results of a vitamin E trial involving residents in long-term care facilities. In a post hoc analysis, they observed a slightly lower common cold incidence in the group that was administered 200 IU/d of vitamin E (relative risk [RR], 0.83; 95% confidence interval [CI], 0.68-1.01). We examined the effect of vitamin E (50 mg/d) on common cold incidence in the Alpha-Tocopherol BetaCarotene Cancer Prevention Study cohort involving 21796 male smokers aged 50 to 69 years at baseline. We found no overall effect of vitamin E on common cold incidence (RR, 0.99; 95% CI, 0.98-1.01). However, in an exploratory subgroup analysis, we found a statistically significant but clinically modest reduction of common cold incidence in city-dwelling participants aged 65 years or older who smoked less than 15 cigarettes/d (RR, 0.72; 95% CI, 0.62-0.83), with no effect among elderly participants living outside cities or smoking more than 15 cigarettes/d (RR, 0.99; 95% CI, 0.941.05). Although these 2 studies suggest that vitamin E might reduce the risk of the common cold by 20% in some subgroups of the elderly population, we consider this a small effect. Given an annual incidence of 1 cold per person, 5 persons would need to take up to 200 IU/d of vitamin E for 1 year to prevent 1 episode of the common cold, which is usually a short and self-limiting nuisance.