The impact of bilateral subthalamic nucleus deep brain stimulation on dyskinesia and levodopa equivalent daily dose in advanced Parkinson’s disease

To assess the effect of bilateral subthalamic nucleus deep brain stimulation (B/L STN DBS) on the progression of dyskinesia and the levodopa equivalent daily dose (LEDD) in advanced Parkinson’s disease (APD) patients 6 months postoperatively. Seventeen APD patients aged 21–80 years with the minimum modified Hoen & Yahr score of 2 while off medication and poor motor function underwent B/L STN DBS from January 2021 to December 2021. They were assessed preoperatively and 6 months postoperatively using the Unified dyskinesia rating scale (UDysRS) and Unified Parkinson’s Disease Rating Scale Part IV (UPDRS IV) for dyskinesia and LEDD dosage. Significant improvement was observed postoperatively in both UDysRS (pre-op 66.53±24.59, post-op 30.88±12.01; P = 0.000) and UPDRS IV (pre-op 9.24±1.75, post-op 5.76±1.39; P = 0.000) scores. The overall clinical improvement using UDysRS was 52.23±16.23%. Each subscale of UDysRS showed significant improvement postoperatively: ON dyskinesia (pre-op 21±7.7, post-op 13.76±5.79; P < 0.05); OFF dystonia (pre-op 8.53±3.26, post-op 4.94±2.70; P < 0.05); impairment (face, pre-op 2.47±2.52, post-op 0.29±0.98, P < 0.05; neck and trunk, pre-op 6.29±4.55, post-op 0.59±0.87, P < 0.05; arms, pre-op 13.06±5.86, post-op 5.76±3.7, P < 0.05; and legs, pre-op 7.18±5.12, post-op 1.29±1.57, P < 0.05); and disability (pre-op 8±3.46, post-op 4.24±2.25; P < 0.05), suggesting high clinical significance. LEDD (pre-op 673.41±212.69mg, post-op 386.82±133.01mg; P = 0.000) showed significant reduction in dosage 6 months postoperatively. LEDD reduction and dyskinesia improvement showed mild-to-moderate positive correlation (r = 0.404). B/L STN DBS helps in improving dyskinesia by reducing LEDD in APD patients.