Introduction: To assess the therapeutic efficacy of selegiline combined with levodopa in the long-term treatment of Parkinson's disease (PD).
Material and methods: A randomized, prospective, double-blind study on 44 patients with PD needing levodopa therapy after the initial double-blind treatment with placebo or selegiline was carried out. The patients were followed-up for 5 years under combination therapy.
Results: Selegiline induced a significant (P < 0.001) slowing in the need to increase the daily levodopa dose in order to compensate for the progression of the disease. After 5 years of combination therapy the mean dose of levodopa was on average 320 mg lower in the selegiline group (405 +/- 59 mg vs 725 +/- 78 mg). The difference in the levodopa doses between the two groups increased along with follow-up time, as also the ratio of the levodopa doses (placebo/selegiline group). The number of daily levodopa doses needed to compensate for the occurrence of motor fluctuations was significantly lower in the selegiline group. The parkinsonian disability did not differ between the two groups because the clinical condition was kept as optimal as possible by adjusting the levodopa dosage. Nine patients in the placebo group needed initiation of additional dopaminergic therapy in comparison to one in the selegiline group (P = 0.004). During the 5-year follow-up period 11 patients were withdrawn from the selegiline group, 7 due to adverse events. There was no difference in mortality between the two groups.
Conclusions: Selegiline therapy offers beneficial long-term effets in the treatment of PD.