Researchers at Vanderbilt University in Nashville said the analysis, known as the Nashville Men's Health Study, included 1,277 participants referred to a urologist for a biopsy of their prostate. Approximately 46 percent of the men reported taking an NSAID, mostly aspirin.

After adjusting for age, race, family prostate cancer history, obesity and other variables that have independent effects on the size of the prostate organ and cancer risk, the researchers found that aspirin use was significantly associated with lower PSA levels.

PSA levels were 9 percent lower in men taking aspirin compared with men who did not take aspirin.

The PSA test is used widely as a method to screen men for the possibility of prostate cancer, with higher blood PSA levels suggesting a greater chance of having prostate cancer. However, high PSA levels can also signify benign prostatic hyperplasia, a non-cancerous enlargement of the prostate organ.

The findings are scheduled to be presented at the American Association for Cancer Research's Seventh Annual International Conference on Frontiers in Cancer Prevention Research.