Purpose: To evaluate the association between active and passive smoking and frequency of colds in women.
Methods: Data on cigarette smoking and frequency and duration of colds were analyzed in the Women's Health Study (WHS), a randomized, double-blind, placebo-controlled trial of low-dose aspirin and vitamin E in the primary prevention of cardiovascular disease and cancer among 39,876 female health professionals.
Results: After adjustment for age, body-mass index, prevalence of asthma and chronic lung diseases, alcohol intake, physical activity, and multivitamin use, current heavy smokers had no appreciable increase in the frequency of colds (relative risk (RR) for >or= 3 versus no colds in the past year, 1.05; 95% confidence interval (CI), 0.80-1.39), but a significantly increased risk of prolonged colds (RR for colds of > 7 vs. 1-3 days, 2.53; 95% CI, 1.95-3.29). There was no difference in the number of days confined to home. Nonsmoking women passively exposed to cigarette smoke had a slightly increased risk of both more frequent colds (RR, 1.33; 95% CI, 1.18-1.51) and more prolonged colds during the previous year (RR, 1.12; 95% CI, 0.99-1.27).
Conclusions: Women who are currently heavy smokers are at increased risk of having colds with longer duration compared with nonsmokers. Nonsmoking women passively exposed to cigarette smoking are at slightly increased risk of having more frequent and longer colds than nonsmoking women not exposed to passive smoke.