Q. I would like to know the symptoms of Parkinson's disease. Can it be detected by a blood test or other laboratory test?
A. Symptoms of Parkinson's disease start most commonly in the late 50s or early 60s and affect about 1 percent of those over 60.
It begins with insidious and slowly progressive symptoms of three types: tremor, muscle rigidity and slowed movements. Often, one of the first manifestations is an intermittent "pill-rolling" tremor of one or both hands while at rest.
Muscles become stiff and the face develops a masklike and expressionless appearance. All movements are slowed. The individual walks with short, shuffling steps and a stooped posture.
Unpredictable falls may lead to broken bones. Slowed speech is monotonous, may be almost inaudible, and is frequently accompanied by drooling.
Rising from a chair becomes difficult. Handwriting gets progressively smaller and there may be problems in buttoning clothes. Other symptoms include impaired memory, depression and sleep disturbances.
The diagnosis of Parkinson's disease is based on clinical findings. There is no diagnostic blood or other laboratory test.
Dr. Margolis is professor of medicine and biological chemistry at the Johns Hopkins School of Medicine and associate dean for academic affairs at the school.