Background: The clinical and neurobiological underpinnings of transient nonmotor (TNM) psychiatric symptoms during the optimization of stimulation parameters in the course of subthalamic nucleus deep brain stimulation (STN-DBS) remain under intense investigation. Methods: Forty-nine patients with refractory Parkinson's disease underwent bilateral STN-DBS implants and were enrolled in a 24-week prospective, naturalistic follow-up study. Patients who exhibited TNM psychiatric manifestations during DBS parameter optimization were evaluated for potential associations with clinical outcome measures. Results: Twenty-nine TNM+ episodes were reported by 15 patients. No differences between TNM+ and TNM- groups were found in motor outcome. However, unlike the TNM- group, TNM+ patients did not report improvement in subsyndromal depression or quality of life. TNM+ episodes were more likely to emerge during bilateral monopolar stimulation of the medial STN. Conclusions: The occurrence of TNM psychiatric symptoms during optimization of stimulation parameters was associated with the persistence of subsyndromal depression and with lower quality of life ratings at 6 months. The neurobiological underpinnings of TNM symptoms are investigated yet remain difficult to explain.
Bibliographical noteFunding Information:
We would like to thank Ms. Veneliza Salcedo for making the illustration. This work is supported by a grant from NIH/NCRR CTSA KL2 (RR024151; to O.A.A.) and the Mayo Foundation (to M.A.F.).
© 2016 S. Karger AG, Basel.
- Deep brain stimulation
- Parkinson's disease
- Psychiatric symptoms
- Subthalamic nucleus