[Effect of slow repetitive transcranial magnetic stimulation on depression in patients with Parkinson 's disease].Srp Arh Celok Lek. 2001 Sep-Oct; 129(9-10):235-8.SA
Parkinson's disease (PD), that has usually been associated with movement disorders, is also associated with depression in about 40% of patients . Transcranial magnetic stimulation (TMS) is a new non-invasive technique for direct stimulation of the cerebral cortical neurons . Several open studies have shown that repetitive TMS (rTMS) at both rapid (rapid rTMSi: > 1 Hz) and low frequencies (slow rTMSi: < 1 Hz) may have antidepressant action [2-6]. The study included 8 patients diagnosed as PD fulfilling the DSM-IV criteria for major depression (5 patients) and dysthymia (3 patients). Magnetic stimulator, 200 Mag-Stim, total output 2 T and a circular coil of 90 mm, were used. For ten consecutive days, between noon and 1 p.m. the patients were stimulated with apprx. 80% of the output (1.6 T) at 0.5 Hz. The daily treatment implied stimulation of both sides of the head (first the right, then the left) at four sites (prefrontal, frontal, parietal and occipital regions) with 5 stimulations each site (20 stimulations per hemisphere). Before the beginning of the study, 2-3 hours after the last stimulation (day 10), 7 and 14 days after completion of the treatment, the patients were subjected to scoring on the Hamilton Depression Rating Scale  and Unified Parkinson's Disease Rating Scale (UPDRS) . The HDRS values before initiation of rTMS were 19.2 +/- 3.1, with significant fall (p < 0.01) after 10 days of stimulation (14.9 +/- 3.2), 17 days (12.2 +/- 2.7) and 24 days (13.6 +/- 5.3) after the beginning of the study, suggesting that the antidepressive effect persisted even two weeks after discontinuation of stimulation. The UPDRS values were monitored concomitantly. The values on this scale failed to alter significantly. In conclusion, rTMS is a relatively safe and painless method associated with antidepressant action in PD patients. Treatment of depression in PD is of great importance, but the choice of medication is accompanied with numerous limitations . Antidepressant action of rTMS and its maintenance for two weeks after discontinuation of stimulation enables usage of this method in PD in phases of exacerbation of depressive symptoms at least over the period required to reach the full effect of selected medication.