THURSDAY, April 9, 2009 (HealthDay News) -- Having more than a couple of drinks a day can double the risk of developing involuntary (essential) tremor, a neurological disorder that affects about 5 million people over the age of 60 in the United States.
Researchers compared lifetime alcohol consumption and neurological symptoms in almost 3,300 people, aged 65 and older, in three areas of central Spain. Regular alcohol consumption was reported by 56 percent of the participants, who were first assessed in 1994-1995 and again in 1997-1998. At the second assessment, essential tremor was diagnosed in 76 participants.
After the researchers accounted for other risk factors, such as depression and smoking, they concluded that people who drank at least three units of alcohol per day more than doubled their risk of essential tremor. At this level of alcohol consumption, every additional year of regular daily drinking increased the risk by 23 percent. While not as great, the risk was also higher among people who drank fewer units of alcohol, but drank regularly.
The study is in the Journal of Neurology, Neurosurgery and Psychiatry.
The researchers noted that alcohol is a known brain toxin, especially in the cerebellum, which is the part of the brain involved in involuntary tremor. Alcohol is often used to relieve symptoms of essential tremor, but this study suggests alcohol may actually speed progression of the condition and worsen symptoms.
The exact cause of involuntary tremor is unclear, but it's believed to be caused by damage to brain cells called Purkinje cells and disrupted signaling between nerve synapses, according to background information in a journal news release about the study.
The American Academy of Family Physicians has more about essential tremor.