Quality of life and depressive symptoms in Parkinson's disease after subthalamic deep brain stimulation: a 2-year follow-up study

To assess the correlation between quality of life (QoL), depressive symptoms and motor signs in patients with Parkinson disease after subthalamic deep brain stimulation (DBS STN). 74 patients, average age 55.6 ± 7 and duration of disease 12.3 years ± 3.8, treated with l STN DBS for PD were included in the study. All patients were evaluated with (UPDRS III), (PDQ-39) (BDI) at baseline and at 6, 12, and 24-month follow up. All patients were also stratified into three groups depending on UPDRS III improvement ( < 30%, 30-60%, > 60%). Scores in all scales significantly decreased from baseline. The improvement in PDQ-39 was 43.3%, in BDI 25.3 %; UPDRS-III 55.5% at 6 months. At 24 months, motor results and QoL deteriorated by 15.6% and 19.6% respectively. BDI remained unchanged. Mean scores at baseline in PDQ-39 were group I 67.4 ± 29.7; II 64.8 ± 32.0; III 53.4 ± 22.0 and for BDI, group I 17.4 ± 12.04; II 14.0 ± 9.7; III- 15.1 ± 10.55. Scores decreased significantly with DBS at 6-month follow-up and mean change was: PDQ-39, group I 42.7%, II- 40.7%, III 51.6%; BDI group I 23%, II 28.1%, III 23.3 %. Reduction of depressive symptoms, motor signs and improvement of QoL in PD after DBS STN are closely related. Improvement of QoL depends significantly on motor symptoms.