ANTHROPOMETRIC AND METABOLIC FACTORS AND RISK OF BENIGN PROSTATIC HYPERPLASIA: A PROSPECTIVE COHORT STUDY OF AIR FORCE VETERANS AMIT GUPTA, SACHIN GUPTA, MARIAN PAVUK, AND CLAUS G. ROEHRBORN ABSTRACT Objectives. The relationship between anthropometric and metabolic factors and benign prostatic hyper- plasia (BPH) is poorly understood. We investigated the associations of BPH with anthropometric and metabolic parameters in this prospective study of Vietnam War veterans. Methods. A total of 1206 participants in the comparison arm of the Air Force Health Study with a median follow-up of 15.6 years were included in this study. The “Ranch Hand” group, occupationally exposed to herbicides, was excluded to eliminate any confounding from exposure to herbicides. BPH was determined by medical record review using the International Classification of Diseases and Related Problems, Ninth Revision. We used Cox proportional hazards regression models for the statistical analysis. Results. The median age for BPH diagnosis was 58.6 years. On multivariate analyses, increasing age (relative risk [RR] 1.14, 95% confidence interval [CI] 1.12 to 1.17), height (RR 1.02, 95% CI 1.004 to 1.03), and fasting blood glucose (RR 1.004, 95% CI 1.001 to 1.007) were associated with increased risk. The effect of age varied with the duration of follow-up. A greater systolic blood pressure (RR 0.992, 95% CI 0.986 to 0.997) was associated with decreased risk of BPH. A dose-response effect was seen for age, height, and systolic blood pressure. No effect was seen for weight, body mass index, change in weight or body mass index, lipids, thyroid hormone status, or the metabolic syndrome. Conclusions. The risk of BPH increased with increasing age, height, and fasting blood glucose levels. The risk was decreased with a greater systolic blood pressure. No relationship was seen between BPH and metabolic syndrome, weight, body mass index, lipid level, or thyroid hormone status. UROLOGY 68: 1198–1205, 2006. © 2006 Elsevier Inc. B enign prostatic hyperplasia (BPH) is among the most common ailments in elderly men. It leads to troublesome lower urinary tract symptoms (LUTS) and is associated with complications such as acute urinary retention, hematuria, stones, uri- nary tract infections, and need for surgical inter- ventions. The relationship of BPH to anthropometric and metabolic factors is unclear. Several studies have been performed, with conflicting results. Although some studies have found a relationship among obe- sity, body mass index (BMI), waist circumference, and BPH 1–9 ; other studies have not found such as- sociations. 10 –14 Similarly, although some studies have reported associations with diabetes, hyper- tension, and dyslipidemia, 3,5,11,15,16 other studies did not find such associations. 8,9 Most of the stud- ies in this field were cross-sectional in design in which exposure and disease were measured simul- taneously. The few longitudinal studies that have been conducted had a maximum follow-up dura- tion of 6 to 21 years. 2,8,10 –12,14 In this longitudinal study of Vietnam War veterans who were followed up for up to 22.5 years, we report the relationship of BPH with anthropometric and metabolic pa- rameters. MATERIAL AND METHODS The Air Force Health Study was a prospective study of Op- eration Ranch Hand veterans and a comparison group of other From the Departments of Urology and Internal Medicine, Univer- sity of Texas Southwestern Medical Center, Dallas, Texas; and SpecPro Incorporated, Air Force Research Laboratory, Air Force Health Study Branch, Brooks City-Base, Texas Reprint requests: Claus G. Roehrborn, M.D., Department of Urology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9110. E-mail: Claus. Roehrborn@UTSouthwestern.edu Submitted: August 16, 2006, accepted (with revisions): Sep- tember 14, 2006 ADULT UROLOGY © 2006 ELSEVIER INC. 0090-4295/06/$32.00 1198 ALL RIGHTS RESERVED doi:10.1016/j.urology.2006.09.034