Efficacy of deep brain stimulation of the subthalamic nucleus in Parkinson's disease 4 years after surgery: double blind and open label evaluation

Abstract
Objective: To evaluate the long term (4 years) efficacy of deep brain stimulation (DBS) of the subthalamic nucleus (STN) in advanced Parkinson’s disease. Methods: We performed a double blind crossover evaluation of the efficacy of DBS of the STN in the “off” medication condition in 10 patients with Parkinson’s disease. Assessments included the Unified Parkinson’s Disease Rating Scale (UPDRS) part III (motor) and two timed tests (arm tapping and walking). Open evaluation of the effect of stimulation in the off and on drug states preoperatively and at 1 and 4 years postoperatively was also conducted. The latter assessment included the UPDRS parts II (activities of daily living) and III (dyskinesia scale and global assessment) as judged by the patient and examiner. The mean amount of levodopa daily dose at base line, 1 year, and 4 years after surgery was compared. Results: A significant (pConclusions: DBS of the STN provides a significant and persistent anti-parkinsonian effect in advanced Parkinson’s disease 4 years after surgery.