Pharmacotherapy on the Background of Electrical Stimulation of the Subthalamic Nucleus in Patients with Parkinson’s Disease

Objective. To analyze pharmacotherapy on the background of stimulation of the subthalamic nucleus (STN). Materials and methods. A total of 54 patients with implanted STN stimulation systems (Medtronic) were investigated from 2003 to 2012. The severity of motor disorders, daily activity, and complications of pharmacotherapy were evaluated using parts II, III, and IV of the Unified Parkinson’s Disease Rating Scale (UDPRS) before surgery and at one, three, and four years of continuing stimulation. The equivalent daily dose of levodopa was evaluated, along with analysis of pharmacotherapy overall. Results and conclusions. The severity of motor impairments in off periods decreased by 52.3% by one year of observation and remained stable for three years (51.8%), after which there was a small increase in the severity of motor symptoms, though not to the pre-operative level. The severity of motor fluctuations and iatrogenic dyskinesia decreased by 64.9%, 70.7%, and 42.7% at the ends of years 1, 3, and 4, respectively. The levodopa equivalent dose showed the greatest decrease by one year (57.7%), with decreases by 52.4% and 38.2% at three and four years, respectively. During the first year, 16.7% of patients took no levodopa. The levodopa dose decreased by 64.6% at one year and then by 56.7% and 43.7% at three and four years, respectively. Dopaminergic receptor agonist monotherapy was used in 12.9% of patients, the proportion receiving agonists in combined therapy increasing from 24.1% to 35.2% during the post-operative period. © 2017, Springer Science+Business Media New York.