BACKGROUND - While statin use has been associated with reduced prostate cancer (PC) aggressiveness, the impact of race and patient characteristics on this association is not well understood. We examined the association between statin use and PC aggressiveness in Caucasians (CA) and African Americans (AA), and explored effect modification by health-seeking behaviors associated with statin use.
METHODS - Of 1,930 cases from the North Carolina-Louisiana Prostate Cancer Project (PCaP), 344 (18%) were classified as aggressive based on clinical criteria. Utilizing non-aggressive cases as referent, logistic regression was used to examine the association between statin use and PC aggressiveness, overall and stratified by race. Smoking and PC screening were examined as effect modifiers of this association.
RESULTS - There was an inverse association between statin use and PC aggressiveness (OR 0. 74; 95%CI 0. 56-0. 96), with comparable effect estimates in both races. Although not statistically significant, statin use was associated with reduced odds ratios for aggressive PC in never-screened men (OR 0. 79; 95%CI 0. 45-1. 39), men screened at low/recommended frequency (≤once/year; OR 0. 66; 95%CI 0. 41-1. 06), and men screened at high frequency (>once/year; OR 0. 78; 95%CI 0. 53-1. 15). Inverse associations between statins and aggressive PC were strongest in never smokers (OR 0. 42; 95%CI 0. 25-0. 72), attenuated in former smokers (OR 0. 84; 95%CI 0. 59-1. 19), and absent in current smokers (OR 1. 36; 95%CI 0. 70-2. 64).
CONCLUSIONS - Statin use was associated with reduced PC aggressiveness in CA and AAs, with strongest inverse associations in non-smokers.
Health-seeking behaviors associated with statin use should be considered when examining the impact of statins on PC aggressiveness.
Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. 2016 Jan 27 [Epub ahead of print]
Emma H Allott, Laura Farnan, Susan E Steck, Lenore Arab, L Joseph Su, Merle Mishel, Elizabeth T H Fontham, James L Mohler, Jeannette T Bensen
Department of Epidemiology, University of North Carolina at Chapel Hill. , University of North Carolina at Chapel Hill. , Epidemiology and Biostatistics, University of South Carolina. , General Internal Medicine, UCLA David Geffen School of Medicine. , Winthrop P Rockefeller Cancer Institute and College of Public Health. , University of North Carolina at Chapel Hill. , School of Public Health, Lousiana State University Health Sciences Center. , Urology, Roswell Park Cancer Institute. , Epidemiology, University of North Carolina