Impulse control behaviors and subthalamic deep brain stimulation in Parkinson disease

Abstract

To determine the clinical and demographic correlates of persistent, remitting, and new-onset impulse control behaviors (ICBs) before and after subthalamic deep brain stimulation (STN-DBS) in Parkinson's disease (PD). We compared the pre- and post-surgical prevalence of ICBs, classified as impulse control disorders (ICD), dopamine dysregulation syndrome (DDS), and punding in 150 consecutive PD STN-DBS-treated patients and determined the association with motor, cognitive, neuropsychological, and neuropsychiatric endpoints. At baseline (before STN-DBS), ICBs were associated with younger age (p=0.045) and male gender (85%; p=0.001). Over an average follow-up of 4.3±2.1years of chronic STN-DBS there was an overall trend for reduction in ICBs (from 17.3 to 12.7%; p=0.095) with significant improvement in hypersexuality (12-8.0%; p=0.047), gambling (10.7-5.3%; p=0.033), and DDS (4.7-0%; p<0.001). ICB remitted in 18/26 patients (69%) and persisted in 8/26 (31%); the latter group was characterized by higher levodopa equivalent daily dose. Patients who developed a new-onset ICB during follow-up (n=11/150) were characterized by younger age (p=0.042), lower dyskinesia improvement (p≤0.035), and a gender distribution with higher prevalence of women (p=0.018). In addition, new-onset ICB was more common among patients with borderline, schizoid, and/or schizotypal traits of personality disorders; persistent ICB in those with obsessive-compulsive traits. PD-related ICBs exhibit a complex outcome after STN-DBS, with a tendency for overall reduction but with age, gender, dopaminergic therapy, and neuropsychiatric features exerting independent effects.