Association of Nonsteroidal Anti-inflammatory Drugs, Prostate Specific Antigen and Prostate Volume

Purpose: Nonsteroidal anti-inflammatory drugs such as aspirin prevent cardiovascular disease and several prior studies suggest that nonsteroidal anti-inflammatory drugs also decrease prostate inflammation and prostate cancer risk. We investigated the association between nonsteroidal anti-inflammatory drug use, prostate specific antigen and prostate volume, hypothesizing that there would be lower prostate specific antigen and prostate volume with nonsteroidal anti-inflammatory drug use. Materials and Methods: The Nashville Men's Health Study uses a multicenter, rapid recruitment protocol to collect clinical, biological, behavioral and body measurement data on 1,277 men older than 40 years who are scheduled for diagnostic prostate biopsy. Nonsteroidal anti-inflammatory drug use was ascertained by survey and clinical interview. Medical charts were reviewed to ascertain current prostate specific antigen, prostate volume and clinical diagnoses following biopsy. Results: Approximately 46% of patients reported receiving nonsteroidal anti-inflammatory drugs, primarily aspirin (37%). After adjusting for age, race and other factors prostate volume was similar between aspirin users and nonusers (47.6 vs 46.0 ml, p = 0.16). In contrast, prostate specific antigen was significantly lower in aspirin users (7.3 vs 8.0 ng/ml, p = 0.01). The association between prostate specific antigen and aspirin was significant in men with latent prostate cancer (6.1 vs 7.3 ng/ml, p <0.01), marginal in patients with high grade prostatic intratepithelial neoplasia (5.0 vs 5.9 ng/ml, p = 0.09) and nonsignificant in those with a negative biopsy (5.6 vs 5.7 ng/ml, p = 0.64). The strongest prostate specific antigen-aspirin association was in men with cancer and a prostate volume of 60 ml or more (7.3 vs 12.7 ng/ml, p <0.01). Conclusions: Prostate specific antigen was significantly lower in aspirin users with latent cancer. Prostate volume was not associated with nonsteroidal anti-inflammatory drug use. Results suggest that aspirin may affect prostate cancer detection, suggesting a potential detection bias to address in future studies of nonsteroidal anti-inflammatory drugs and prostate cancer prevention.