Effects of deep brain stimulation on functional autonomy and quality of life in Parkinson's disease: A systematic review and meta-analysis

Abstract

Background Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established therapy for advanced Parkinson's disease (PD), primarily targeting motor complications refractory to pharmacological treatment. However, its long-term impact on functional autonomy and quality of life (QoL) remains debated. Objective This systematic review with meta-analysis aimed to evaluate the effects of STN-DBS on autonomy and QoL in people with PD. Methods Following PRISMA guidelines, a systematic search of PubMed, Scopus, Embase and Web of Science was conducted to identify studies including adults with PD treated with STN-DBS and reporting measures of autonomy and/or quality of life. Results Thirty-two studies met inclusion criteria. Meta-analyses showed effect estimates favoring DBS at 6 months (SMD = 0.83[0.38;1.29]) and at 1 year (SMD = 0.49[-0.02;0.99]) for autonomy. Similar trends were observed for QoL, with SMD = 0.60[0.49;0.71] at 6 months and SMD = 0.48[0.0;0.96] at 1 year. At 2 years, small but significant pooled effects persisted, for both autonomy SMD = 0.40[0.13;0.67] and QoL SMD = 0.25[-0.04;0.53]. However, at 5 years, pooled effects were no longer statistically significant for either autonomy SMD = 0.37[-0.55;1.29] or QoL SMD = −0.01[-0.25;0.22], indicating a progressive attenuation of benefit over time. Conclusions STN-DBS provides robust short- and mid-term benefits in functional autonomy and QoL in PD. Long-term outcomes are variable and influenced by disease progression and non-motor symptoms. Standardized outcome reporting, larger multicenter trials, and integration of rehabilitative and psychosocial interventions are needed to optimize benefits.