Long term follow-up on quality of life and its relationship to motor and cognitive functions in Parkinson's disease after deep brain stimulation

Abstract

IntroductionWe aimed to examine temporal changes in health-related quality of life (HRQOL) and its relationship with motor and cognitive functions in patients with Parkinson's disease (PD) after subthalamic nucleus deep brain stimulation (STN-DBS). MethodsIn total, 31 patients with PD were enrolled in this study (mean age: 66.7±0.9years; mean disease duration: 11.6±3.7years). Participants completed the Unified Parkinson's Disease Rating Scale and the Parkinson's Disease Questionnaire-39. Cognitive function was assessed using the Mini Mental State Examination, the Frontal Assessment Battery, and the Montreal Cognitive Assessment. Postoperative evaluation was performed at three months, one year, three years, and five years after surgery; temporal changes in the correlation between HRQOL and motor and cognitive functions were evaluated at all follow-up periods. ResultsAll patients completed postoperative clinical evaluations after three months, after one year. Of the 31 participants, twelve completed postoperative clinical evaluations after three years and seven after five years. Motor functions showed significant improvement over the five-year follow-up period. The mobility subdomain of the HRQOL worsened whereas the total score did not change significantly over years. Cognitive functions were not significantly impaired during follow-up periods. HRQOL was basically not significantly correlated with motor and cognitive functions during the follow-up period. ConclusionsThe mobility subdomain of the HRQOL worsened after surgery, and the improvement in motor functions was basically not correlated with HRQOL after STN-DBS in patients with PD. Cognitive functions were not significantly impaired during follow-up periods.