Monograph series on aging-related diseases: XII. Parkinson's disease--recent developments and new directions.

Parkinson's disease, a chronic progressive disorder of the central nervous system characterized by tremor, rigidity and bradykinesia, usually affects those over the age of 50. Recent developments in research on Parkinson's disease include investigation of the possible role of diet and a growing interest in genetics and inherited factors. The identification of biological markers and other environmental risk factors will play a significant role in future research of the disease as they will be important in the development of prevention strategies.