Metabolic syndrome, diabetes mellitus, and the subsequent development of prostate cancer

Abstract

5158 Background: The lifetime risk of an American man developing prostate cancer (PC) is one in six. Metabolic syndrome (MS) is a cluster of medical disorders (hypertension, dyslipidaemia, hyperglycaemia, obesity) associated with the subsequent development of diabetes mellitus (DM). DM and MS afflict 11% and 22% of US adults respectively. MS and DM are associated with disturbed lipid homeostasis, and hypogonadism. DM and MS predispose to the development of gastrointestinal and endometrial cancer. DM and MS's influence on PC is less clear; some studies have suggested that whereas DM inhibits PC, MS promotes PC development. Methods: The Bezafibrate Infarction Prevention study was a randomized trial of fibrate therapy for the secondary prevention of ischemic heart disease. Between 1990–2 15524 men and women with ischemic heart disease were screened, of whom 3090 entered the trial. 81% were male. Participants were divided into three groups according to baseline parameters: (A) those with neither MS nor DM, (B) those with MS but no DM, (C) those with DM (with or without MS). MS was defined according to ATPIII guidelines. DM was defined by medical history or fasting glucose > 125 mg/dL. Follow-up for PC incidence and all-cause mortality was obtained through the Israeli cancer registry and the Ministry of the Interior respectively. Analysis accounts for differences in age and non-cancer-related-mortality between groups. Ethics approval was obtained. Results: 1350 participants were excluded due to missing data or previous cancer diagnosis, leaving 11,541 men. Mean age at enrollment 61 years (45–74). Median follow-up was 12 years. There were 6119 (53%), 3,376 (29%), and 2,046 (18%) participants in groups A, B and C respectively. Overall there were 459 cases of PC; 298, 123 and 48 in groups A, B and C. The age adjusted PC rates were 4.30, 3.61 and 2.55 per 1,000 patient years in groups A, B and C respectively (A vs C p = 0.003). Data were also analyzed examining PC incidence as a function of ‘number of components of MS present’ after pooling groups A, B and C. Relative risk of developing PC was 1.00, 0.92, 0.90, 0.69, 0.71, and 0.33 for 0, 1, 2, 3, 4, and 5 components respectively. Conclusions: A baseline diagnosis of DM (highly significant) or MS (trend) was associated with a decreased prostate cancer rate over the subsequent 12 years. No significant financial relationships to disclose.