July 18, 2001 -- It's a common stereotype of elderly people: Trembling hands lifting a teacup or fumbling with the buttons of a sweater. If you have a relative with uncontrollable shaking of the hands, it's only natural to worry about whether it will happen to you one day.
Until now, researchers really didn't have an answer to this question, but a new study of elderly people with hand tremors shows that about 20% of their relatives can expect to develop shaky hands as they age.
The risk is highest for first-degree relatives and people with a family member who developed tremors at a young age, says Elan D. Louis, MD, author of a report appearing in the June issue of the Annals of Neurology.
The condition, called essential tremor, affects millions of people in the U.S., and while it's in no way life-threatening, it does make simple tasks like eating, writing, brushing teeth or hair, and driving difficult and frustrating.
Louis, a neurologist at Columbia University's College of Physicians and Surgeons in New York, compared people with essential tremor of the hands and their relatives with people unaffected by tremor and their relatives.
Close relatives of people with essential tremor were five times more likely to develop tremors than relatives of people without tremor -- and 10 times more likely if a relative began experiencing hand tremors at or before age 50.
It's important to realize that having an increased risk of tremor doesn't mean you're going to get it as you get older or that it will be a significant problem, says Jack Jallo, MD, a neurosurgeon who specializes in treating people with essential tremor.
"How severe the disease will be is unknown," says Jallo, of Temple University Hospital in Philadelphia. "You can have a very mild essential tremor, which is insignificant, or you can have a moderately severe essential tremor which does respond to medication, although the medications aren't great."
The device works by jamming a pathway in the brain that allows the tremors to continue, says neurologist Rajeeb Kumar, MD. The majority of patients who have the surgery are typically in their 60s, but Kumar, of the Colorado Neurological Institute Movement Disorders Center in Englewood, Colo., says it can work just as well on people in their 80s if their health is otherwise good.
It's important for people with a family history of tremor to understand and be reassured that essential tremor has nothing to do with Parkinson's disease, says Dan Lieberman, MD, a neurosurgeon at the Good Samaritan Movement Disorders Clinic in Phoenix.
When doctors examine patients for essential tremor or Parkinson's, they look for very different types of tremor, he says. With essential tremor, the tremor happens when you move, while the Parkinson's tremor happens when you are still.