1004 Background: Hydroxymethylglutaryl-CoA reductase inhibitors (statins)are commonly used to control high cholesterol. These agents that have been shown to induce apoptosis and inhibiting tumour growth and metastasis in human cancer cell lines and animal tumour models. We studied the association of prostate cancer and statins in veterans. Methods: VISN 16 data warehouse, which contains clinical and demographic information about all veterans (>1.4 million patients) cared for at the 10 VA Medical Centers in 4 states comprising the South Central VA health Care Network in the mid-south region of the US, was queried from Oct 1998 to June 2004. Retrospective case control design was used. The primary variable of interest was prostate cancer (ICD-9 code 185) and the use of statins prior to the diagnosis of prostate cancer. Multivariate logistic regression analysis was done to adjust for covariates including age, body mass index, smoking, diabetes, and race. Statistical analysis was performed using SAS software version 9.0 (Chicago, IL). Results: A total of 443,805 patients were evaluated and of these, 159,874 were on statins. A total of 26,139 were diagnosed with prostate cancer. Statin use was associated with a significant protective effect for prostate cancer (Odds ratio 0.46, 95% CI 0.45 to 0.48). The risk factors associated with an increased risk of prostate cancer included age (OR 1.082, 95% CI 1.081 to 1.084), body mass index (OR 1.015, 95% CI 1.012 to 1.018), smoking (OR 1.13, 95% CI 1.07 to 1.120), diabetes (OR 1.09, 95% CI 1.06 to 1.13), and race - blacks vs whites (OR 1.57, 95% CI 1.50 to 1.63). Conclusions: Statins are protective against the development of prostate cancer after controlling for age, body mass index, smoking, diabetes, and race. An internal consistency of the database is reflected by an increased risk associated with other documented risk facors such as age, race etc. Our data should be evaluated with caution, given the limitations of the population, the database, and this being a case control study. Dose, duration, and particular statin used were not factored into the analysis. If these results are confirmed in a large prospective study they may provide necessary evidence to consider the use of statin drugs in prostate cancer prevention. No significant financial relationships to disclose.