Nutrient Intake in Relation to Bladder Cancer among Middle-aged Men and Women

This population-based case-control study examined the association between selected nutrients, foods, and diet behaviors and bladder cancer. Bladder cancer cases (n = 262) were identified from the Surveillance, Epidemiology, and End Results Program cancer registry for western Washington, and controls (n = 405) were identified through random digit dialing. Cases were diagnosed between January 1987 and June 1990, and eligible subjects were Caucasian, aged 45–65 years, and residents of King, Pierce, or Snohomish counties. Subjects completed a self-administered, 71-item food frequency questionnaire and a structured telephone interview. Analyses were conducted by logistic regression analysis and included adjustment for age, sex, smoking (current, former, never), and county. Odds ratios and their 95% confidence intervals for highest versus lowest level of intake were examined. An inverse association was found between the risk of bladder cancer and dietary retinol (odds ratio (OR) across quartiles: 1.00, 1.09, 0.97, and 0.52; 95% Cl 0.29–0.97; trend p value = 0.03) and dietary vitamin C (OR across quartiles: 1.00, 0.96, 0.67, and 0.50; 95% Cl 0.28–0.88; trend p value = 0.009), adjusted for calories. The use of multivrtamin supplements daily over the 10-year period ending 2 years before diagnosis versus no use was associated with a decreased risk of bladder cancer (OR = 0.39; 95% Cl 0.24–0.63) as was use of supplemental vitamin C (OR for >502 mg/day over the 10 years vs. none = 0.40; 95% CI 0.21–0.76). Increased intake of fruit was associated with a decreased risk of bladder cancer (OR across quartiles: 1.00, 1.24, 0.72, and 0.53; 95% Cl 0.30–0.93; trend p value = 0.01, adjusted for calories), while increased use of fried foods was associated with an increased risk of bladder cancer (OR across quartiles: 1.00, 1.51, 1.81, and 2.24; 95% Cl 1.25–4.03; trend p value = 0.006). This study provides modest evidence that certain nutrients, foods, and supplementation may affect the incidence of bladder cancer. Am J Epidemiol 1996; 144: 485-95.