The Effectiveness of Deep Brain Stimulation in Dystonia: A Patient-Centered Approach

To systematically evaluate the effectiveness of deep brain stimulation of the globus pallidus internus (GPi-DBS) in dystonia on pre-operatively set functional priorities in daily living.

Fifteen pediatric and adult dystonia patients (8 male; median age 32y, range 8-65) receiving GPi-DBS were recruited. All patients underwent a multidisciplinary evaluation before and 1-year post DBS implantation. The Canadian Occupational Performance Measure (COPM) first identified and then measured changes in functional priorities. The Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) was used to evaluate dystonia severity.

Priorities in daily functioning substantially varied between patients but showed significant improvements on performance and satisfaction after DBS. Clinically significant COPM-score improvements were present in 7/8 motor responders, but also in 4/7 motor non-responders.

The use of a patient-oriented approach to measure GPi-DBS effectiveness in dystonia provides an unique insight in patients' priorities and demonstrates that tangible improvements can be achieved irrespective of motor response.

Functional priorities in life of dystonia patients and their caregivers vary greatlyThe effect of DBS on functional priorities did not correlate with motor outcomeHalf of the motor 'non-responder' patients reported important changes in their prioritiesThe effect of DBS in dystonia should not be measured by motor outcome alone.