AGE AT ONSET - THE MAJOR DETERMINANT OF OUTCOME IN PARKINSONS-DISEASE

Factors at presentation which influenced the course of the disease and response to treatment were assessed in 125 de novo patients with Park inson's disease. Ninety-eight patients were available for re-assessmen t at 5 years. Older patients presented earlier after the onset of symp toms, deteriorated more rapidly, and were significantly more likely to develop dementia and impairment of balance. Increasing age and symmet rical disease predicted the new appearance of imbalance. Age of onset did not predict dyskinesia or end of dose failure, A low tremor score at baseline and female gender were predictive of the early appearance of dyskinesia. Patients who experienced end of dose failure were takin g a significantly higher dose of levodopa. Once dose and duration of t reatment were corrected for, no baseline features were predictive of e nd of dose failure. The dose of levodopa at 5 years was positively cor related to baseline disease severity as measured by the Columbia score . We conclude that the age of onset of symptoms of Parkinson's disease is a major determinant of the course of the disease and response to t reatment.