Intake of fruits and vegetables and polymorphisms in DNA repair genes in bladder cancer.

The objective is to investigate the relationships between fruit and vegetable intake, DNA repair gene polymorphisms and the risk of bladder cancer. We have analyzed a hospital-based case-control study of 266 individuals with incident, histologically confirmed bladder cancer diagnosed between 1994 and 2003. Controls (n = 193) were patients treated for benign diseases recruited daily in a random fashion from the same hospital as the cases. All cases and controls were interviewed face-to-face for major risk factors, along fruit and vegetable consumption. Odds ratios (ORs) for fruit and vegetable intake and DNA repair gene polymorphisms were adjusted for age and smoking status, using unconditional logistic regression. A statistically significant decreased risk was observed for fruit and vegetable intake above median (versus below the median) [unadjusted OR 0.61, confidence interval (CI) 95% 0.50-0.96 and OR 0.54, CI 95% 0.39-0.80, respectively]; the decreased risk persisted after adjustment for age and cigarette smoking (OR 0.73, CI 95% 0.49-1.01 and OR 0.86, CI 95% 0.56-1.08, respectively). The fruits and vegetables associated with decreased risks included leafy green vegetables, cruciferous vegetables, apples and citrus fruits. We did not find any interactions between DNA repair gene polymorphisms and fruit and vegetable intake. This study found a reduced risk associated with fruit and vegetable intake. No interaction was observed between fruit and vegetable consumption and DNA repair gene polymorphisms.