Body mass index, cholesterol level and risk of lung cancer in Lithuanian men

Abstract

Objective: Our objective was to investigate the association between body mass index (BMI), total serum cholesterol (TSC) level and risk of lung cancer in a Lithuanian population-based cohort study.

Materials and methods: The study included 6729 men initially free from cancer. During the follow-up (1978-2008), 358 lung cancer cases were identified. Cox proportional hazards models were used to estimate hazard ratios (HR) and corresponding 95% confidence intervals (95% CI).

Results: Following adjustment for age, smoking, alcohol consumption, and education, BMI 25-29.9 and ≥30.0kg/m(2) hazard ratios (HR) were significantly associated with decreasing risk for lung cancer, HR=0.73; 95% CI: 0.59, 0.91 and 0.62; 95% CI: 0.45, 0.87, respectively (ptrend=0.001) compared to BMI<25 kg/m(2). Inverse association between BMI and lung cancer was observed among current smokers. We found no evidence that BMI was associated with decreased lung cancer risk in never smokers, although small sample size precluded meaningful analysis. Not significantly lower risk of lung cancer among participants in the 5th quintile compared with the 1st quintile of TSC concentrations was observed. HR per 1 mmol/l increase of TSC was 0.90; 95% CI: 0.82, 1.00. Findings suggest consistent effects of BMI and TSC when follow-up was 1993-2008.

Conclusion: Our results show an inverse dose-dependent association between lung cancer risk and BMI in Lithuanian men, especially among current smokers. The inverse association could not be attributed to preclinical cancer effect hypothesis. TSC level was not statistically significantly related to a lung cancer incidence.

Keywords: Body mass index; Cohort studies; Lithuania; Lung cancer risk; Total serum cholesterol.