March 17, 2004 -- Men may be more likely to develop Parkinson's disease than women, a new study shows.
Researchers analyzed several studies on the incidence of Parkinson's disease in the population and found that men were 1.5 times more likely to develop the disease than women.
About 1 million people in the U.S. have Parkinson's disease, and the risk of developing the disease increases with age.
Men Face Higher Risk of Parkinson's
Researchers say previous studies on death rates from Parkinson's disease have shown that men might suffer disproportionately from the condition. But they say death rates aren't an accurate indicator of the disease because they don't include the number of new cases and the cause of death isn't always confirmed.
In this study, researchers analyzed studies on the incidence of Parkinson's disease among populations in the U.S., China, Poland, Italy, Spain, and Finland. The incidence of a disease reflects the number of new cases developed or diagnosed during a specific time period within a certain population.
After adjusting for age, the analysis showed that men were 1.5 times more likely to develop Parkinson's disease than women.
The results appear in the April issue of the Journal of Neurology Neurosurgery and Psychiatry.
Researchers say the male gender itself may be a risk factor for Parkinson's disease, or it may just be a marker for other risk factors that men are exposed to more than women, such as working with toxic chemicals or head injuries, which have been associated with higher risks of the disease.
Another explanation may be that estrogen may have a protective effect on the female nervous system.
Whatever the reasons behind the increased risk of Parkinson's disease among men, researchers say learning more about them may yield new clues about how the mysterious disease develops.