Long - term follow - up study of variable frequency stimulation mode deep brain stimulation for axial symptoms in Parkinson's disease

Objective To focus on the efficacy at variable frequency stimulation (VFS) after deep brain stimulation (DBS) for the treatment of axial symptoms in Parkinson's disease (PD). Methods Clinical data of 12 patients with PD who underwent bilateral DBS followed by VFS more than one year from January 2018 to June 2022 at Tianjin Huanhu Hospital, Tianjin University were retrospectively analyzed. Axial symptoms were assessed using Unified Parkinson's Disease Rating Scale (UPDRS)-gait posture, Timed Up and Go Test (TUGT) time and the occurrence of freezing of gait (FOG), The Freezing of Gait - Questionnaire (FOG - Q), and Berg Balance Scale (BBS). The above indicators were recorded one week before DBS surgery and in the drug "off" period (baseline), at the end of high frequency stimulation (the end of HFS), at one month follow-up of VFS (short-term VFS), and at one year or more follow-up of VFS (long-term VFS). Results Compared with baseline, BBS scores increased at the end of HFS (t = - 2.845, P = 0.008); UPDRS-gait posture (t = 12.703, P = 0.000; t = 11.737, P = 0.000), TUGT time (t = 8.923, P = 0.000; t = 8.025, P = 0.000) and the occurrence of FOG (t = 4.448, P = 0.000; t = 4.181, P = 0.000), and FOGQ scores (t = 9.186, P = 0.000; t = 8.186, P = 0.000) decreased, while the BBS scores increased (t = - 7.686, P = 0.000; t = - 6.106, P = 0.000) in both short-term VFS and long-term VFS. Compared with the end of HFS, UPDRS-gait posture (t = 11.583, P = 0.000; t = 10.618, P = 0.000), TUGT time (t = 6.922, P = 0.000; t = 6.022, P = 0.000) and the occurrence of FOG (t = 3.612, P = 0.001; t = 3.344, P = 0.002), and FOG-Q scores (t = 7.915, P = 0.000; t = 6.915, P = 0.000) decreased, while the BBS scores increased (t = - 4.842, P = 0.000; t = - 3.262, P = 0.003) in short-term VFS and long-term VFS. Conclusions For PD patients with HFS but poor axial symptoms efficacy after DBS, the use of VFS significantly improves multifaceted axial symptoms with reliable long-term efficacy.