A population-based study of daily nonsteroidal anti-inflammatory drug use and prostate cancer

Objective: To investigate the association between daily use of nonsteroidal anti-inflammatory drugs (NSAIDs) and prostate cancer. Patients and Methods: Subjects were 50- to 79-year-old white men randomly selected in January 1990 from the Olmsted County, Minnesota, community (n=1362) from among participants in a longitudinal study of lower urinary tract symptoms. At the beginning of the study, all medications that were used daily, including prescription and nonprescription NSAIDs, were ascertained by trained interviewers. Men who developed a histologically proved diagnosis of prostate cancer during a median of 66 months (maximum, 6 years) of follow-up were identified from a complete review of the community medical record. Results: Twenty-three (4%) of 569 NSAID users and 68 (9%) of 793 nonusers developed prostate cancer during follow-up (P=.001). The relative odds of prostate cancer were 0.45 (95% confidence interval [CI], 0.28-0.73) in NSAID users compared with nonusers. This inverse association with NSAID use increased with increasing age at study onset. Thus, the relative odds of prostate cancer among NSAID users were 0.9 (95% CI, 0.4-2.2) in men aged 50 to 59 years, 0.4 (95% CI, 0.2-0.8) in men aged 60 to 69 years, and 0.2 (95% CI, 0.1-0.5) in men aged 70 to 79 years compared with similarly aged men who did not use NSAIDs. Conclusion: The study findings suggest that daily use of NSAIDs may be associated with a lower incidence of prostate cancer in men aged 60 years or older. The stronger effect among older men suggests that NSAIDs may prevent the progression of prostate cancer from latent to clinical disease.