Cardiorespiratory fitness and smoking-related and total cancer mortality in men

Purpose: We investigated the association between cardiorespiratory fitness and smoking-related, nonsmoking-related, and total cancer mortality in men. Methods: We followed 25,892 men, age 30-87 yr, who had a preventive medical evaluation, including a maximal exercise test and self-reported health habits. There were 335 cancer deaths (133 from smoking-related cancer, 202 from nonsmoking-related cancer) during an average of 10 yr of follow-up (259,124 man-yr). Results: After adjustment for age, examination year, smoking habits, alcohol intake, body mass index, and diabetes mellitus, there was an inverse association between cardiorespiratory fitness levels and smoking-related (P < 0.001 for trend), nonsmoking-related (P = 0.001 for trend), and total cancer mortality (P < 0.001 for trend). Moderate and high levels of cardiorespiratory fitness were associated with lower risk of smoking-related and nonsmoking-related cancer mortality when compared with low fitness in men. We also observed that smoking-related mortality rates were progressively lower across low, moderate, and high fitness groups in former (P = 0.06 for trend) and current (P = 0.04 for trend) smokers. Conclusion: We conclude that cardiorespiratory fitness may provide protection against cancer mortality in men.