May 4, 2000 (San Diego) -- Smokers desperate for a good reason to light up can now claim it prevents Parkinson's disease. Well, sort of ?.
Several studies over the past 30 years have shown that those who smoke cigarettes have a lower risk of developing movement disorders like Parkinson's. However, the defensive smoker may be only half right, according to a study Dutch researchers presented here at the 52nd annual meeting of the American Academy of Neurology. It's the cause of the addictive behavior that may be protective and not something in the cigarette, they argue.
Smokers aren't alone, either. While studying the health habits and food diaries of 55 people who went on to develop Parkinson's disease, Patricia Willems-Giesbergen, MD, found they were more likely to drink alcohol or coffee than were people who didn't develop the disease. And in the case of coffee drinkers and cigarette smokers, she found that the more they indulged, the lower their risk.
Parkinson's disease is a chronic disorder affecting the brain, and it has symptoms such as stiff and rigid muscles, tremor, changes in speech, and poor balance. It is caused by a destruction of cells in certain areas of the brain, together with a reduction in a chemical called dopamine. On the other hand, addictive behavior -- like smoking, drinking, and taking drugs -- is believed to be associated in part with high levels of dopamine, which is connected with behavior that is described as "pleasure-seeking."
"When healthy people smoke or drink, they release dopamine in the brain ... which gives a kind of rewarding feeling," explains Willems-Giesbergen, who is a researcher at Erasmus Medical Center in Rotterdam, the Netherlands. "It's a good feeling and, therefore, they want to smoke or drink again. We think that people with Parkinson's disease don't have that specific dopamine release because their levels are too low. The use of coffee, alcohol, and cigarettes is not rewarding for them ... and so they are less likely to [repeat the behavior]."
The link Parkinson's disease has with alcohol and coffee is not as strong as the one it has with tobacco, Willems-Giesbergen says. Clearly, there are more questions to be answered. To more fully understand the relationship between dopamine, addictive tendencies, and Parkinson's, Willems-Giesbergen is busy collecting more data from the study, which is still in progress.