Long-term Outcomes for Mood, Anxiety and Apathy in Dystonia with Bilateral DBS Surgery (P1-1.Virtual)

Objective: We examined the long-term effects of DBS on mood, anxiety and apathy in patients with dystonia who underwent DBS at our center.

Background: Mood, anxiety and apathy are frequent nonmotor symptoms reported by patients with dystonia. While the motor outcomes with deep brain stimulation (DBS) surgery targeted to bilateral globus pallidus internus (GPi) or subthalamic nucleus (STN) are well reported, psychiatric outcomes at long-term follow-up are not known. Nonmotor effects of DBS in dystonia are important as they can impact the quality of life.

Design/Methods: In an IRB approved protocol, we extracted longitudinal data collected in patients with dystonia DBS using Unified Dystonia Rating Scale for motor outcomes, Beck Depression Inventory, Beck Anxiety Inventory (BAI), State-Trait Anxiety Inventory (STAI), and Apathy Scale collected before surgery and at six months, one year, three years, and at last available follow-up after surgery (maximum 12 years).

Results: We analyzed data on 69 patients; 66 GPi, 3 STN, 8 with STN as rescue lead in addition to GPi; 32 males; mean age 55±22 years; 43 idiopathic, 13 genetic, 41 generalized dystonia. Compared to baseline, the motor outcomes at the last follow-up improved by 28.4% and the depression scores improved by 14.2% (n=69, p=0.04); however the apathy scores revealed worsening by 23.6% (n=28, p=0.02). Anxiety scores measured with STAI (n=26) at 3 ± 2 years follow-up and BAI (n=22) at 6 ± 5 years follow-up did not reveal a significant change. There was no change in the frequency of suicidal thoughts, and there was no report of suicidal attempts in our cohort.

Conclusions: While DBS in dystonia led to a slight improvement in depression at long-term follow-up, it worsened apathy. DBS had no effects on suicidal thoughts and attempts and anxiety levels. These findings are important for long-term patient counseling.