WEDNESDAY, April 13, 2005 (HealthDay News) -- People with a movement disorder called essential tremor, involving a shaking of the hands head, voice or body, are more than twice as likely to develop dementia in old age as people who don't have the disorder, a Spanish study suggests.
"This is the first study to suggest that essential tremor is associated with the development of dementia. We don't yet know whether the dementia is due to the same underlying problem that is causing the essential tumor or whether it is caused by another problem," study author Dr. Julio Benito-Leon, of Mostoles General Hospital in Madrid, said in a prepared statement.
Experts estimate that up to 20 percent of people over age 65 are affected by essential tremor.
For about three years, the researchers tracked outcomes in 202 elderly people with essential tremor and more than 3,500 others with no dementia or movement disorders. Over that time, 15 (7.4 percent) of individuals with essential tremor developed dementia, compared to 126 (3.5 percent) of people in the control group.
The study was presented April 13 at the annual meeting of the American Academy of Neurology in Miami Beach, Fla.
More information
The U.S. National Library of Medicine has more about essential tremor.
