WEDNESDAY, Aug. 30 (HealthDay News) -- Older men who regularly take aspirin or a similar painkiller may help keep prostate enlargement at bay, a new study finds.

The common condition, called benign prostatic hyperplasia, typically affects one of every four men ages 40 to 50 and almost half of those over 70, experts say. Enlarged prostate can lead to frequent urination and other bothersome effects.

However, men who regularly took a non-steroidal anti-inflammatory drug (NSAID) "had a reduction of 50 percent in enlargement and a 35 percent reduction in moderate to severe urinary problems," said Jenny St. Sauver, a Mayo Clinic epidemiologist who led the study, which was reported in the American Journal of Epidemiology.

It didn't matter which NSAID a man was taking: aspirin, ibuprofen, naproxen (Aleve) or a more expensive cox-2 inhibitor such as Celebrex, St. Sauver said. "Eighty percent were taking daily aspirin," she said. "We did look at the other drugs, but the differences were not statistically significant."

The study was prompted by several earlier studies that suggested a decreased risk of prostate cancer for men who took NSAIDs regularly. This study included nearly 2,500 men living in the neighborhood of the Mayo Clinic in Minnesota. Data on NSAID use and prostate enlargement arose from questionnaires the men completed every two years from 1990 to 2002.

There are several theories as to how NSAIDs might keep prostates from enlarging. According to St. Sauver, the drugs may reduce prostate cell growth or increase the natural death of these cells. Another theory credits the drugs' anti-inflammatory activity.

The findings should not be seen as a green light for men to rush out and start taking these painkillers without consulting a doctor first, the experts stressed. Men should always be cautious about taking NSAIDs, St. Sauver said, because the drugs raise risks for gastrointestinal bleeding.

"We would like to see the results of our study replicated," she said. "If it can be, it would be important to figure out what kind of dose and what kind of timing would be proper."

The warning against indiscriminate use of NSAIDs was repeated in stronger terms by Eric Jacobs, senior epidemiologist at the American Cancer Society.

Jacobs headed a study last year that found that men who had taken NSAIDs regularly for a long period of time were at slightly decreased risk of developing prostate cancer.

"The important thing about NSAIDs in general is that they can have very serious side effects, gastrointestinal bleeding that can be fatal," Jacobs said. "We do not recommend using NSAIDs for cancer prevention."

Many of the men in the Mayo Clinic study were taking low-dose aspirin to protect against heart disease, he said. "Currently, the decision about whether or not to take aspirin is based on balancing cardiovascular benefits with the risk of gastrointestinal bleeding," Jacobs said. "If someone is at high risk, the doctor can decide that the benefits outweigh the risk. Currently, cancer is not part of the risk-benefit ratio."

More information

There's more on prostate enlargement at the U.S. National Institute of Diabetes and Digestive and Kidney Diseases.