Abstract

Objectives: Workers in over 40 different occupations are suspected to have an elevated risk of bladder cancer, but strong evidence of increased risk is apparent for very few occupational groups. We investigated the association between occupation and bladder cancer in a hospital-based case-control study conducted in Spain. Methods: A total of 1,219 patients with transitional cell carcinoma of the urinary bladder and 1,271 controls, selected from 18 hospitals in Spain between June 1998 and September 2000. All participants were asked to provide detailed information on life-time occupational history, smoking habits, medical history, and other factors. We used unconditional logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI) for each occupation and industry, adjusting for age, hospital region, smoking duration, and employment in a high-risk occupation for bladder cancer. Results: Statistically significant increased risks were observed among men employed as machine operators in the printing industry (OR=2.8;95%CI=1.3-6.2), transportation equipment industry (OR=1.6;95%CI=1.1-2.6), and those who worked for > 10 years in the electric/gas/sanitary services (OR=3.9;95%CI=1.5-10.4) and hotels and other lodging (OR=3.1;95%CI=1.3-7.3). Men who worked as miscellaneous mechanics and repairers (OR=2.0;95%CI=1.1-3.6) and as supervisors in production occupations (OR=2.1;95%CI=1.2-3.6) also had excess risks for bladder cancer. Male farmers, and those who worked in crop and livestock production, had decreased risks for bladder cancer. We found no significant associations between occupation or industry and bladder cancer risk among women. Conclusions: We did not observe excess bladder cancer risk for many of the occupations identified as being a priori at high risk. Examination of more detailed job exposure information should help clarify these associations.