Study finds heavy coffee drinkers are less likely to get the diseaseAn intriguing new study suggests coffee may prevent Parkinson’s disease. How a product that makes people jittery could keep them from getting a disease that gives them tremors is a paradox not examined in the study of 8,004 Japanese-American men in Hawaii.
BUT THE researchers said the benefits are probably due to caffeine — apparently the more, the better — and they suggest some theories about how it might work.
Outside experts said that if the findings hold up, they could lead to ways to treat Parkinson’s more effectively or even prevent the disease, a degenerative brain disorder that affects about 1 million Americans.
The study found that men who didn’t drink coffee were five times more likely to develop Parkinson’s than those who drank the most — 4½ to 5½ 6-ounce cups a day. Non-coffee drinkers were two to three times more likely to get the disease than men who drank 4 ounces to four cups a day.
The researchers said it is uncertain whether their results would hold true in women and other ethnic groups.
The study was published in the Journal of the American Medical Association. It was led by Dr. G. Webster Ross, a neurologist at the Veterans Administration Medical Center in Honolulu.
Ross said it is possible that heavy coffee drinkers have a brain composition that may make them resistant to Parkinson’s. Previous studies have found low rates of Parkinson’s in “thrill-seeking” people who tend to engage in high-risk behavior like smoking and heavy drinking, and heavy coffee drinking also fits that personality profile, he said.
But he also suggested that caffeine may somehow protect against the nerve-cell destruction that causes Parkinson’s. Still, Ross said it is too early to recommend coffee as a treatment.
“Hopefully, this will lead to more basic research on caffeine and its effect on areas of the brain affected by Parkinson’s disease,” Ross said.
He took into account other factors that could explain the findings, such as cigarette smoking, which has also been linked to a decreased Parkinson’s risk.
Paul Carvey, director of the neuropharmacology research laboratories at Rush-Presbyterian-St. Luke’s Medical Center in Chicago, said the study is important because it traced the benefits to caffeine, showing similar results with caffeine-laden foods other than coffee.
Dr. Abraham Lieberman, medical director for the National Parkinson Foundation, called the results “very interesting and very provocative.” He said that if caffeine does have benefits, it is unclear whether it can actually prevent Parkinson’s or slow its progression.
Parkinson’s is usually associated with aging, though it has made headlines recently with actor Michael J. Fox’s disclosure that he was diagnosed seven years ago at age 30. Attorney General Janet Reno and Muhammad Ali are among others with Parkinson’s.
The disease involves gradual deterioration of nerve cell clusters that make the chemical dopamine, which helps control muscle movements. Ross and colleagues speculated that caffeine might increase dopamine levels.
Symptoms of Parkinson’s include hand and head tremors, loss of balance, and stiffness. Dementia and depression also can result.
Medication helps victims function, but over time the disease usually renders patients unable to care for themselves. Its cause is unknown.
The researchers examined data from the ongoing Honolulu Heart Program. Participants — age 53 on average when the study began — were asked about coffee consumption at the outset in 1965 and again in 1971. The researchers then measured Parkinson’s disease rates from 1991 to 1996. The disease developed in 102 men.