¹ Department of Neurology and Neurosurgery, Grenoble University Hospital and INSERM U318, Joseph Fourier University, Grenoble, France
² Federation of Neurology, Clinical Investigation Centre, La Pitié-Salpétrière Hospital, Paris, France
³ CLP-Santé, Paris, France
⁴ Department of Neurology and Neurosurgery, Lille University Hospital, Lille, France
⁵ Department of Neurology and Neurosurgery, Bordeaux University Hospital, Bordeaux, France

Correspondence to:
Correspondence to:
Pierre Pollak
Department of Neurology, Grenoble University Hospital, BP 217, 38043 Grenoble Cedex 9, France; Pierre.Pollak{at}ujf-grenoble.fr

Background: High frequency stimulation of the subthalamic nucleus (STN) is an alternative but expensive neurosurgical treatment for parkinsonian patients with levodopa induced motor complications.

Objective: To assess the safety, clinical effects, quality of life, and economic cost of STN stimulation.

Methods: We conducted a prospective multicentre study in 95 consecutive Parkinson’s disease (PD) patients receiving bilateral STN stimulation and assessed its effects over 12 months. A double blind randomised motor evaluation was carried out at 3 month follow up, and quality of life, self care ability, and predictive factors of outcome following surgery were assessed. The cost of PD was estimated over 6 months before and after surgery.

Results: The Unified Parkinson’s Disease Rating Scale (UPDRS) motor score improved by 57% (p<0.0001) and activities of daily living improved by 48% (p<0.0001) at 12 month follow up. Double blind motor scoring improved by 51% at 3 month follow up (p<0.0001). The total PD Quality of Life Questionnaire (PDQL-37) score improved by 28% (p<0.001). The better the preoperative motor score after a levodopa challenge, the better the outcome after STN stimulation. Five patients developed an intracerebral haematoma during electrode implantation with permanent after effects in two. The 6 month costs of PD decreased from 10 087 before surgery to 1673 after surgery (p<0.0001) mainly because of the decrease in medication. These savings allowed a return on the procedure investment, estimated at 36 904 over 2.2 years.

Conclusions: STN stimulation has good outcomes with relatively low risk and little cost burden in PD patients with levodopa induced motor complications.

Abbreviations: PD, Parkinson’s disease; PDQL-37, Parkinson’s Disease Quality of Life Questionnaire; STN, subthalamic nucleus; UPDRS, Unified Parkinson’s Disease Rating Scale

Keywords: economic study; high frequency stimulation; Parkinson’s disease; quality of life; subthalamic nucleus