Should levodopa therapy for Parkinson's disease be started early or late? Clinical course of the major tetrad in 122 parkinsonian patients treated with levodopa over 14 years.

The study was carried out to clarify whether levodopa should be started early or late in the course of Parkinson's disease. In this study, 122 patients treated with levodopa over 14 years were included. The time course of each of the four major signs (rigidity, static tremor, akinesia and postural instability) and Yahr stage was investigated in three groups, Yahr stage I/II group, Yahr stage III group and Yahr stage IV/V group, taking into consideration the time period preceding the initiation of levodopa therapy. When the time periods in years since onset of symptoms were matched, no significant differences were recognized among the three groups. There seemed to be no benefit in delaying levodopa therapy but, rather, levodopa therapy should be started as early as possible. The declining efficacy often recognized during levodopa therapy was thought probably due to progression of Parkinson's disease itself rather than to levodopa.