ANAHEIM, California—Prostate cancer can now be added to the list of malignancies for which nonsteroidal anti-inflammatory agents (NSAIDs) may have a protective effect, according to experimental and clinical research presented at the American Urological Association annual meeting.
A study of 887 men in the Baltimore Longitudinal Study of Aging found a trend toward a protective effect of NSAIDs other than aspirin(Drug information on aspirin) (abstract 259). While the differences were not significant, the relative risk was 0.76 for users of NSAIDs other than aspirin users, 0.85 for men using aspirin, and 1.15 for men using acetaminophen.
Each year of NSAID use was associated with a 6% reduction in risk, also supporting the existence of a dose-response effect, reported Jay D. Pearson, PhD, director of epidemiology, Merck Research Laboratories, West Point, Pennsylvania.
The study followed the men for a median of 9.4 years and found 96 histologically confirmed cases of prostate cancer. Time-dependent proportional hazards analyses were used to estimate the relative risk of prostate cancer associated with medication use (ever/never or length of exposure) adjusted for age, education, and calendar year. Calendar year was included as a covariate because of secular trends in the use of NSAIDs and PSA screening.
"These results from a prospective cohort study suggest a reduction (not statistically significant) in the risk of prostate cancer associated with the use of NSAIDs: 24% reduction for NSAIDs, 15% reduction for aspirin, and no reduction for acetaminophen," Dr. Pearson said. "The lack of an association with acetaminophen also suggests that these reductions are not likely to be due to confounding with pain medications in general."
COX-2 Inhibitors
Experimental studies reported at the AUA meeting provided some insight into NSAIDs’ possible protective effect. The expression of cyclooxygenase-2 (COX-2) has been shown to be increased in human prostate cancers, and treatment with COX-2 inhibitors suppressed this expression, according to researchers from Memorial Sloan-Kettering Cancer Center and Louisiana State University Health Science Center, Shreveport (abstract 1184).
