Fruit and vegetable consumption and risk of COPD: A prospective cohort study of men

Abstract

Background: Antioxidants present in fruits and vegetables may protect the lung from oxidative damage and prevent COPD. Aims: To determine the association between fruit and vegetable consumption and risk of COPD by smoking status in men. Methods: The population-based prospective Cohort of Swedish Men included 44 335 men, aged 45-79 years, with no history of COPD at baseline. Fruit and vegetable consumption was assessed with a self-administered questionnaire. Results: During a mean follow-up of 13.2 years, 1918 incident cases of COPD were ascertained. A strong inverse association between total fruit and vegetable consumption and COPD was observed in smokers but not in never-smokers (p-interaction=0.02). The agestandardised incidence rate per 100 000 person-years in the lowest quintile (<2 servings/day) of total fruit and vegetable consumption was 1166 in current smokers and 506 in ex-smokers; among those in the highest quintile (≥5.3 servings/day), 546 and 255 per 100 000 person-years, respectively. The multivariable HR of COPD comparing extreme quintiles of total fruit and vegetable consumption was 0.60 (95% CI 0.47 to 0.76, p-trend <0.0001) in current smokers and 0.66 (95% CI 0.51 to 0.85, p-trend=0.001) in ex-smokers. Each one serving per day increment in total fruit and vegetable consumption decreased risk of COPD significantly by 8% (95% CI 4% to 11%) in current smokers and by 4% (95% CI 0% to 7%) in ex-smokers. Conclusions: These results indicate that high consumption of fruits and vegetables is associated with reduced COPD incidence in both current and ex-smokers but not in never-smokers.