Fluid intake-to-bed time, nocturia frequency and the risk of urothelial carcinoma of the bladder: a case-control study.

Objectives: To clarify the potential role of fluid intake-to-bed time and nocturia frequency on bladder cancer risk in a hospital-based case-control study with Chinese people. Materials and Methods: Four hundred and seven patients with histologically diagnosed bladder cancer and 400 matched controls were enrolled in this study. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression model. Results: After adjustment for potential confounders, the fluid intake-to-bed time was associated with a decreased risk of BCa, with an OR of 0.586 (95% CI = 0.375-0.916, <= 1h) and 0.257 (95% CI = 0.162-0.407, > 1h). The adjusted OR of BCa for subjects with more nocturia frequency (= 2 times) was 2.268 (95 % CI = 1.481-3474), compared to those with no nocturia. Conclusion: We suggested strong protective effect of long fluid intake-to-bed time on BCa risk, especially in ones with >= 2 times nocturia frequency. These results provide evidence for identifying high-risk individuals and modifying their behaviors and lifestyle.