Body mass index and lung cancer risk in never smokers

Abstract

Background. A relationship between body mass index (BMI) and lung cancer risk in never smokers has not been reported precisely. To evaluate the risk of lung cancer associated with BMI in never smokers, we conducted a case-control study.

Methods. The relationship between BMI and the risk of lung cancer in never smokers was investigated in a study of 204 lung cancer cases and 398 controls admitted between 1987 and 2005. Controls were selected from hospitalized age-matched never-smoking patients with non-malignant respiratory disease.

Results. When compared with BMI of the leanest group (BMI<20.8) in men, no inverse association between BMI and lung cancer was observed after the adjustment for age (the second BMI group: BMI≥ 20.8 to < 22.9; p=0.683, the third BMI group: BMI≥ 22.9 to < 24.9; p=0.745, and the highest BMI group: BMI≥ 25.0; p=0.327). Similarly, no association in women was found between BMI and lung cancer in these three BMI groups (the second group, p=0.639; the third group, p=0.667; the highest group, p=0.978) when compared with that of the leanest BMI group.

Conclusions. Our present study indicated that the association between leanness and the risk of lung cancer might be influenced by other factors such as smoking.