PDQ-39 predicts quality of life after DBS for Parkinson's disease: Prospective observational study

Abstract

Background: The identification of predictors of improvement in quality of life (QoL) in Parkinson's disease (PD) patients is fundamental for identifying the best candidates for deep brain stimulation (DBS) surgery. Objectives: The primary outcome was the change in QoL of a cohort of patients with PD after DBS surgery, measured using Parkinson's Disease Questionnaire 39 (PDQ-39). Secondary outcomes included motor symptoms according to the Movement Disorders Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS part III) and metabolic effects assessed by body mass index (BMI) and waist circumference. Methods: A prospective observational study was conducted to compare outcomes in the best medical treatment (BMT) plus neurostimulation (DBS group) with BMT alone (BMT group). Results: Forty-one patients with PD were enrolled between 2021 and 2023: Thirty patients underwent DBS surgery, and eleven patients were treated with BMT alone. Participants were reassessed between 6 to 12 months after surgery. PDQ-39 SI score had a mean improvement of 42.3% in the DBS group after surgery (p<0.001), and a mean improvement of 44.5% compared to the BMT group (p<0.001). A linear regression model suggested that the baseline PDQ-39 SI score explains 33.6% of QoL improvement after DBS surgery (p=0.001). MDS-UPDRS-III had a mean improvement of 38.7% in the DBS group. There was an increase in BMI of 1.05% and 3.0 cm on waist circumference after surgery (p<0.001). Conclusions: Preoperative PDQ-39 SI scores could be useful to guide the selection of patients for DBS surgery. Adverse effects related to DBS surgery such as metabolic features should be considered in the decision.