The effect of long-term levodopa therapy on depression level in de novo patients with Parkinson's disease.

20) became non-depressed, while five patients (22%) among 23 initially non-depressed became depressed. With long-term levodopa therapy, the UPDRS-motor score significantly improved (35+/-15. 7-18+/-7.6), but the BDI score was unchanged (18+/-9.3-19+/-9.2). The initial BDI score was significantly and inversely correlated to the parkinsonian motor symptoms, but their percentage changes were not correlated to each other. These results provide strong support to previous observations that levodopa therapy does not alter parkinsonian depression as well as providing additional evidence to support the role of non-dopaminergic mechanisms in parkinsonian depression.