History of weight and obesity through life and risk of benign prostatic hyperplasia

OBJECTIVE: The relation of anthropometric measures, diabetes, hypertension and hyperlipidemia with benign prostatic hyperplasia (BPH) risk was investigated. DESIGN: Hospital-based case-control study. SUBJECTS: Cases were 1369 men with histologically confirmed BPH, and controls were 1451 men below 75 y, admitted to hospital for acute non-neoplastic diseases. MEASUREMENTS: Using a structured questionnaire, trained interviewers collected information on self-reported height and weight, and measured waist and hip circumference of patients. The odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional multiple logistic regression models. RESULTS: Compared to the corresponding lowest quartile, the OR for the highest one were 0.76 (95% CI 0.59-0.98) for body weight, 0.71 (95% CI 0.54-0.94) for waist-to-hip ratio and 0.87 (95% CI 0.70-1.09) for body mass index (BMI, kg/m2). Compared to a lowest lifelong BMI <20.7 kg/m2, the OR was 1.56 (95% CI 1.25-1.95) for a lowest lifelong BMI (greater-than or equal to)23.7 kg/m2. The OR was 0.74 (95% CI 0.60-0.93) for a lifelong increase of BMI (greater-than or equal to)6.1 kg/m2, compared to <1.6 kg/m2. No association emerged for history of diabetes, hypertension and hyperlipidemia. CONCLUSIONS: Overweight was modestly, inversely related to BPH. The hypothesis of reduced testosterone levels in obese individuals may explain the different BPH risk and need to be tested.