Addictive Behavior Cause Linked To Lower Parkinson's Risk
American Academy Of Neurology http://www.aan.com
Link
5-8-00
SAN DIEGO, CA - Amidst the mountain of evidence that
smoking is harmful, there has been one bit of contrary evidence
over the past few years. Studies have consistently found that
smokers have lower rates of Parkinson's disease. However, the
first explanation that comes to mind - that some ingredient in
cigarettes helps prevent Parkinson's may not be correct.
Researchers in the Netherlands have found evidence that higher
consumption of coffee and alcohol is also associated with a lower
incidence of Parkinson's. This, say the authors, suggests that
smoking and other addictive behaviors may be a result of the same
brain chemistry that helps prevent Parkinson's. Results of the study
were presented at the American Academy of Neurology,s 52nd
Annual Meeting in San Diego, CA, April 29 May 6, 2000.
The theory investigated in this study suggests that smokers smoke
because their brains have high levels of dopamine, a brain chemical
implicated in so-called "novelty-seeking" behavior and addiction.
People with lower levels of brain dopamine are not as likely to
become addicted, but they may be more likely to develop
Parkinson's disease, which results from drastic reductions in
dopamine in the brain.
If this theory is correct, then intake of other addictive substances
should also be associated with a reduced incidence of Parkinson's.
This is what the Dutch team sought to prove with data from the
large Rotterdam Study, an ongoing study of almost 8,000 subjects,
aged 55 and older, who have been followed for up to ten years.
As with previous studies, this one found that cigarette smokers had
lower levels of Parkinson's, by almost 50 percent, than did
nonsmokers. "Moreover, there was a dose-effect relationship
between the amount smoked over a lifetime and the risk of
Parkinson's disease," said study author Patricia
Willems-Giesbergen, MD, a researcher at the Erasmus Medical
Center in Rotterdam. "The risk of Parkinson's decreased with an
increase in the amount smoked."
As for coffee, people who drank high amounts had a lower
incidence of Parkinson's. The beverage also had a dose-effect
relationship with the disease whereby the risk for the disease rose
as the amount of coffee consumed decreased. For alcohol, the
researchers found that high consumption was related to a lower
risk of Parkinson's. However, there was no dose-effect relationship
noted.
The results support the hypothesis that patients predisposed to
Parkinson's disease by their brain dopamine levels are more likely
to restrict the use of addictive agents, said Willems-Giesbergen.
But she cautions that the Rotterdam subjects need to be followed
for a longer time to confirm the data.
The American Academy of Neurology, an association of more than
16,500 neurologists and neuroscience professionals, is dedicated to
improving patient care through education and research.
For more information about the American Academy of Neurology,
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-- Flash (flash@flash.hq), May 14, 2000