Nonprescription Painkillers Reduce Parkinson's Disease Risk


LOS ANGELES, Nov. 5 -- Parkinson's disease risk was lowered by 20% with regular aspirin use and by up to 56% with regular non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs), researchers found.The findings contribute to growing evidence for a protective role for non-aspirin NSAIDs and perhaps for aspirin at anti-inflammatory doses, Angelika D. Wahner, Ph.D., of the University of California, Los Angeles, and colleagues, reported in the Nov. 6 issue of the journal Neurology.However, it's definitely too early to recommend NSAIDs as a prevention strategy, especially in view of gastrointestinal bleeding and other risks associated with NSAIDS, said Beate Ritz, M.D., Ph.D., a co-author on the study, in an interview with MedPage Today.
Action Points
Explain to interested patients that NSAIDs may have a protective effect against Parkinson's disease.
Caution patients that regular use of higher dose aspirin and non-aspirin NSAIDs may carry other risks, such as gastrointestinal bleeding.
The researchers studied 293 Parkinson's disease patients within three years of their first diagnosis as well as 286 age-, race-, and gender-matched controls in rural California from 2001 through May 2006.
Parkinson's disease was confirmed by a movement disorder specialist as clinically probable or possible. A medical questionnaire evaluated use of aspirin or non-aspirin NSAIDs once a week or more at any point with a duration of at least one month, number of pills taken per day or week in each category, treatment duration, and age at first and last use.
For aspirin, 35.2% of cases and 41.3% of controls reported regular use (at least two pills a week for at least one month). For non-aspirin NSAIDs, 18.4% of cases and 31.8% of controls reported regular use at some point.
The less frequent use among cases than controls suggested lower Parkinson's disease risk with use of non-aspirin NSAIDs (odds ratio: 0.50, 95% confidence interval: 0.34 to 0.74) and a similar trend with aspirin (OR: 0.72, 95% CI: 0.51 to 1.01).
The protective association for non-aspirin NSAIDs persisted for two years after discontinuation of regular use (OR: 0.61, 95% CI: 0.39 to 0.95), but diminished at five and 10 years. Aspirin's effects persisted through five years but not through 10.
Longer duration of non-aspirin NSAID use increased the protective effect of regular use (OR: 0.44 for two or more years use, 95% CI: 0.26 to 0.74), but increasing the dosage did not improve the association.
For aspirin, the protective effect became stronger but remained insignificant for at least two years of use at higher doses among women (OR: 0.51, 95% CI: 0.26 to 1.02).
The reason a trend for benefit with aspirin among women and not men might have been because of dose, Dr. Wahner and colleagues said.
"Regular male users may be using low-dose baby aspirin (no more than 75 mg per pill) for cardiovascular disease and heart problems while women may be using higher doses (500 to 1,000 mg per day) for other indications such as rheumatic disorders or headaches," they wrote.
"If women are indeed using higher doses, this would suggest that a protective effect is only provided by the high anti-inflammatory doses of aspirin," they added.
The neuroprotective results are biologically plausible based on prior animal studies and the role of neuroinflammation in the development of Parkinson's disease, the researchers said.
"NSAIDs may exert their anti-inflammatory effect by inhibiting proinflammatory cyclooxygenase (COX) enzymes, which have been implicated in the pathogenesis of Parkinson's disease," they wrote.
Further studies are needed to determine the effect of different NSAIDs individually, dosage, and whether use "during particular life epochs or NSAID use concurrent with a damaging neurotoxic insult is most efficacious," they concluded.
The study was supported by National Institute of Environmental Health Sciences grants, pilot funding from the Southern California Environmental Health Sciences Center, and the American Parkinson Disease Association. The researchers reported no conflicts of interest.
Primary source: NeurologySource reference: Wahner AD, et al "Nonsteroidal anti-inflammatory drugs may protect against Parkinson disease"Neurology 2007; 69: 1836-1842.