In the latest study to suggest that anti-inflammatory drugs may protect against brain disorders, researchers have found that regular use of ibuprofen may lower a person's risk of Parkinson's disease.

But the findings are still preliminary and people should not start popping the common painkiller in hopes of warding off the progressive brain disorder, Harvard researchers say.

Parkinson's disease is caused by the loss of brain cells that control movement. Symptoms include shaking, rigidity, slow movements, and unsteadiness.

The findings, presented at the annual meeting of the American Academy of Neurology, came from data collected in a large study of nearly 150,000 men and women. The participants were tracked over eight-and-a-half years, during which time 413 developed Parkinson's disease.

Does Ibuprofen Stand Alone?

"Our findings showed that ibuprofen users were 35 percent less likely to develop Parkinson's disease than nonusers," says researcher Alberto Ascherio, MD, DrPH, associate professor of nutrition and epidemiology at Harvard School of Public Health in Boston.

Surprisingly, this benefit was only seen in patients who took ibuprofen and not those who took aspirin, other anti-inflammatory drugs, or acetaminophen, he tells WebMD.

The more frequently a person took ibuprofen, the greater the benefit, the study showed. Those who used ibuprofen less than twice weekly were 27 percent less likely to develop Parkinson's disease, while daily users were 39 percent less likely to develop Parkinson's.

But there was no link between the length of time that ibuprofen users had been taking the medication and Parkinson's disease, Ascherio says.

The researchers did not study whether the dose of ibuprofen had any effect on the risk of Parkinson's disease.

Age, sex, and smoking status -- known risk factors for Parkinson's disease -- could not explain the results.

Surprising Findings

Ascherio says he was "somewhat surprised" that the benefits did not extend to aspirin or other anti-inflammatory drugs.

It could be a statistical anomaly due to the fact that three-quarters of anti-inflammatory users in the study took ibuprofen. "Maybe we only had the statistical power to see an effect with ibuprofen," he says.

Previous studies have shown a broader impact of anti-inflammatory drugs on Parkinson's disease prevention.

Alternately, there could be an ibuprofen-specific benefit against Parkinson's disease, he says.

Ascherio and his co-investigators plan to follow the patients for at least two more years to see if they can find the answers to these and other questions.

For now, though, "people should not change their behavior based on this study," he says.

Walter Rocca, MD, professor of neurology and epidemiology at the Mayo Clinic in Rochester, Minn., agrees. 'Further study is needed before we can recommend anyone take ibuprofen for the purpose of preventing Parkinson's disease," he says.

Inflammation Linked to Parkinson's

Rocca says the findings make sense from a biological point of view.

"There's quite a bit of literature suggesting that Parkinson's disease results from ongoing inflammation of the brain," he tells WebMD. As a result, there's good reason to think anti-inflammatory drugs can slow or interfere with this process, he says.

Inflammation is the body's most common response to infection or injury. Fluids seep into the affected area, making it red and swollen. This attracts immune cells that set off a barrage of chemical signals -- including pain signals.

Alzheimer's disease also involves brain inflammation. Previous studies have suggested that anti-inflammatory drugs help prevent this disease, too.

Examples of anti-inflammatory drugs are ibuprofen, naproxen, and indomethacin.

Earlier this month, the FDA asked manufacturers of many anti-inflammatory drugs to include warnings on labels about potential heart and stomach ulcer bleeding risks. Aspirin is also an anti-inflammatory drug but was not included in the FDA alert. Acetaminophen (Tylenol) is not an anti-inflammatory drug.

By Charlene Laino, reviewed by Michael W. Smith, MD

SOURCES: American Academy of Neurology 57th Annual Meeting, Miami Beach, Fla., April 9-16, 2005. Alberto Ascherio, MD, DrPH, associate professor of nutrition and epidemiology, Harvard School of Public Health, Boston. Walter Rocca, MD, professor of neurology and epidemiology, Mayo Clinic, Rochester, Minn.