Marked improvement of psychotic symptoms after electroconvulsive therapy in Parkinson disease

Psychosis is common and often medically intractable in Parkinson disease (PD). Sometimes, its management is essential for the determination of the prognosis of PD. There have been several lines of studies demonstrating the effectiveness of electroconvulsive therapy (ECT) for depression in PD but very few for psychosis. The purpose of this retrospective study was to examine the effects of acute ECT on PD-associated psychosis.

The subjects were 5 elderly PD patients (duration, 2-10 years); 4 of whom were diagnosed as "other substance (antiparkinsonian medications)-induced psychotic disorder, with hallucinations," and as 1 "psychotic disorder due to PD, with hallucinations," according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision. Two patients had comorbidity of major depressive disorder, single episode. The psychosis, being refractory to antipsychotics, was treated with a course of acute ECT. Psychiatric conditions were evaluated using the Brief Psychiatric Rating Scale (BPRS), the Hamilton Depression Rating Scale (HDRS), and the Global Assessment of Functioning (GAF) scale. Motor function was assessed using the Hoehn and Yahr staging.

The total BPRS and GAF scores after ECT improved significantly compared with those just before ECT. The Hoehn and Yahr staging also showed significant improvement. No marked adverse effects were seen. Duration of the improvement was between 5 and 30 weeks in followed-up patients.

Acute ECT was effective for medically refractory psychosis in patients with PD regardless of the comorbidity of depression. Our results suggest a possible indication of acute ECT for refractory psychosis in patients with PD.