UC San Diego

Background

The aim of this study was to investigate modifiable lifestyle factors of smoking, exercise, and obesity with bladder cancer mortality.

Patients and methods

We used mortality-linked data from the National Health Information Survey from 1998 through 2006. The primary outcome was bladder cancer-specific mortality. The primary exposures were self-reported smoking status (never- vs. former vs. current smoker), self-reported exercise (dichotomized as "did no exercise" vs. "light, moderate, or vigorous exercise in ≥ 10-minute bouts"), and body mass index. We utilized multivariable adjusted Cox proportional hazards regression models, with delayed entry to account for age at survey interview.

Results

Complete data were available on 222,163 participants, of whom 96,715 (44%) were men and 146,014 (66%) were non-Hispanic whites, and among whom we identified 83 bladder cancer-specific deaths. In multivariate analyses, individuals who reported any exercise were 47% less likely (adjusted hazard ratio [HR_adj], 0.53; 95% confidence interval [CI], 0.29-0.96; P = .038) to die of bladder cancer than "no exercise". Compared with never-smokers, current (HR_adj, 4.24; 95% CI, 1.89-9.65; P = .001) and former (HR_adj, 2.95; 95% CI, 1.50-5.79; P = .002) smokers were 4 and 3 times more likely, respectively, to die of bladder cancer. There were no significant associations of body mass index with bladder cancer mortality.

Conclusion

Exercise decreases and current smoking increases the risk of bladder cancer-specific mortality. These data suggest that exercise and smoking cessation interventions may reduce bladder cancer death.