(Ivanhoe Newswire) -- Smoking for a greater number of years may reduce
the risk of Parkinson's disease, but smoking a larger number of cigarettes per
day does not.
Several studies have shown that smokers have a lower risk of developing
Parkinson's disease.
"These results could guide the development of studies on various tobacco
components with animal models to help understand the relationship between
smoking and Parkinson's disease," study author Honglei Chen, MD, PhD, of the
National Institute of Environmental Health Sciences in Research Triangle Park,
N.C., was quoted as saying. "Research to reveal the underlying chemicals and
mechanisms is warranted; such studies may lead to a better understanding of the
causes of Parkinson's disease. However, given the many adverse consequences of
smoking, no one would suggest smoking in order to prevent Parkinson's disease."
The study involved 305,468 AARP members age 50 to 71 who completed a survey on
diet and lifestyle at the time and again about 10 years later. During the
intervening 10 years, 1,662 of the people had developed Parkinson's disease.
Current smokers were 44 percent less likely to develop Parkinson's disease than
people who had never smoked. People who had smoked in the past and quit were 22
percent less likely to develop Parkinson's than people who had never smoked.
People who smoked for 40 or more years were 46 percent less likely than people
who never smoked to develop Parkinson's disease. Those who smoked for 30 to 39
years were 35 percent less likely to have the disease than nonsmokers. In
contrast, those who smoked for one to nine years were only 8 percent less likely
to get the disease.
The risk of developing Parkinson's disease did not change based on how many
cigarettes a person smoked per day.
Chen noted that studies have shown that smoking is not associated with a slower
progression of the disease once Parkinson's develops or a reduced risk of death,
so he said there is no evidence to support the use of nicotine or other
smoking-related chemicals in treating the disease.
SOURCE: Neurology, online, March 10, 2010