Risk of serious extrapyramidal symptoms in patients with Parkinson's disease receiving antidepressant drugs: A pharmacoepidemiologic study comparing serotonin reuptake inhibitors and other antidepressant drugs

To compare the risk of occurrence of "serious" extrapyramidal symptoms (EPS) between selective serotonin reuptake inhibitors and other antidepressant drugs in patients with Parkinson's disease (PD), the authors performed a retrospective study using the French Pharmacovigilance Database (i.e., the database recording all serious adverse drug reactions reported in France by physicians to the National French Pharmacovigilance Network). Patients with PD were identified from the case reports including at least one antiparkinsonian drug (except anticholinergics). The authors studied patients with PD exposed to at least one antidepressant (classified as imipraminics, selective serotonin reuptake inhibitors, or "other") drug. EPS were defined as aggravation of the parkinsonian symptoms. Of the76,640 case reports registered in the database between January 1, 1995, and December 31, 2000, 916 were identified as patients treated with at least one antiparkinsonian drug, including 199 treated with antidepressant drugs. Among them the authors found nine case reports of EPS (i.e., 4.5% of the patients with PD treated with at least one antidepressant). The odds ratio for EPS was 2.18 (0.47-11.35) for selective serotonin reuptake inhibitors, 1.17 (0.22-5.50) for imipraminics, and 0.74 (0.10-4.06) for other antidepressants. This study failed to find any significant difference in the occurrence of serious EPS according to the different classes of antidepressant drugs in patients with PD treated with dopaminergic antiparkinsonian drugs.