Background: Abnormal involuntary movements (dyskinesias) are common in patients with Parkinson disease (PD) as a consequence of the disease and dopaminergic replacement therapy. Early morning off-medication choreic dyskinesias have been recently reported after fetal dopaminergic cell transplantations in patients with advanced PD.
Objective: To determine the frequency and severity of the early morning off-medication dyskinesias in consecutive patients with advanced PD and an insufficient response to medical management before they undergo neurosurgery.
Methods: Consecutive patients with advanced idiopathic PD were examined and videotaped before undergoing neurosurgery that included pallidotomy, fetal transplantation, or deep brain stimulation. The examination took place in the morning in the practically defined off state, at least 12 hours after the last dose of dopaminergic drugs. Parkinson disease was characterized using the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr stage. Dyskinesias were rated with the Abnormal Involuntary Movements Scale and the Rush Dyskinesia Rating Scale. Patients' characteristics and medications were compared using the Wilcoxon rank sum and the Fisher exact tests.
Results: Of 68 consecutive patients (44 [65%] men and 24 [35%] women), 11 (16%) had early morning off-medication dyskinesia, with a 95% upper confidence limit of 24%. Focal dystonia was the most common off-medication dyskinesia, and occurred in 10 patients (15%), with a 95% upper confidence limit of 22%; and off-choreic dyskinesia occurred in 1 patient (1.5%), with a 95% upper confidence limit of 4%. There was no difference in PD medications between the patients with and those without dyskinesias.
Conclusions: The most common form of off-medication dyskinesia seen in patients with advanced PD is dystonia. Early morning off-medication choreic dyskinesias are rare but do occur in patients with advanced PD before surgical intervention. The presence and type of off-medication dyskinesias should be monitored in clinical and surgical studies in patients with PD as part of the safety and evaluation of clinical benefits.