A Comparison of LEDD and Motor Scores Following STN-DBS Treatment in Patient with Young Onset vs. Late Onset Parkinson's Disease

Introduction: We compared the role of subthalamic nucleus deep brain stimulation (STN-DBS) in the management of medically refractory idiopathic Parkinson's disease in patients with relatively young onset (< 40 years of age) Parkinson's disease (YOPD) and patients with relatively late onset Parkinson's disease (>= 56 years of age, rLOPD). Methods: A total of 33 patients with YOPD (18 patients, median age 32.5 years, range, 20-40 years) and rLOPD (15 patients, median age 58.0 years, range, 56.0-67.0 years) underwent STN-DBS between May 2000 and May 2008. We divided the patients into YOPD and rLOPD as the age of disease onset. The median follow-up period was 43 months (range, 12-95 months). We assessed Hoehn and Yahr stages, activities of daily living, and Unified Parkinson's Disease Rating Scale (UPDRS) motor scales (III) for all patients preoperatively and at six months postoperatively. We measured levodopa equivalent doses (LEDD) and stimulation parameters preoperatively, six months postoperatively, and 12 months postoperatively. Results: There were no significant differences in UPDRS motor scales between two groups at preoperative and six-month postoperative drug off/stim on, but UPDRS III was lower in rLOPD at six-month postoperative drug on/stim on state. A significant difference was noted in the improvement of UPDRS III between two groups for preoperative drug off and drug on conditions, but no difference was seen between two groups in a comparison of drug off/stim on vs. drug on/stim on conditions. Stimulation parameters and postoperative LEDD were not different between the two groups. Preoperative dyskinesia was more common in YOPD patients and, psychotic problems were more common in rLOPD patients. Conclusions: Patients with YOPD and rLOPD exhibited comparable UPDRS motor scores and LEDD six months postoperatively. Levodopa could be prescribed at optimum doses following STN-DBS in patients with YOPD as abnormal movements are better controlled following STN-DBS implantation. Stimulation parameters were not different between the two groups. Our results suggest the age of onset does not influence response to STN-DBS Parkinson's disease patients.