Subthalamic nucleus stimulation in advanced Parkinson’s disease: blinded assessments at one year follow up
- B Ford1,
- L Winfield1,
- S L Pullman1,
- S J Frucht2,
- Y Du3,
- P Greene2,
- J H Cheringal2,
- Q Yu1,
- L J Cote2,
- S Fahn2,
- G M McKhann II1,
- R R Goodman1
- 1Center for Movement Disorders Surgery, Columbia-Presbyterian Medical Center, Columbia University, New York, USA
- 2Department of Neurology, Columbia-Presbyterian Medical Center
- 3Center for Biostatistics and Epidemiology, Columbia-Presbyterian Medical Center
- Correspondence to: Dr B Ford Neurological Institute, 710 West 168th Street, New York, New York 10032, USA;
- Received 4 September 2003
- Accepted 20 November 2003
- Revised 11 November 2003
Objective: To measure the effect of deep brain stimulation (DBS) of the subthalamic nucleus in patients with advanced Parkinson’s disease.
Design: Open label follow up using blinded ratings of videotaped neurological examinations.
Patients: 30 patients with advanced Parkinson’s disease (19 male, 11 female; mean age 58.8 years; mean disease duration 12.8 years), complicated by intractable wearing off motor fluctuations and dopaminergic dyskinesias.
Main outcome measures: Unified Parkinson’s disease rating scale (UPDRS), part III (motor), score at one year, from blinded reviews of videotaped neurological examinations. Secondary outcomes included the other UPDRS subscales, Hoehn and Yahr scale, activities of daily living (ADL) scale, mini-mental state examination (MMSE), estimates of motor fluctuations and dyskinesia severity, drug intake, and patient satisfaction questionnaire.
Results: Subthalamic nucleus stimulation was associated with a 29.5% reduction in motor scores at one year (p<0.0001). The only important predictors of improvement in UPDRS part III motor scores were the baseline response to dopaminergic drugs (p = 0.015) and the presence of tremor (p = 0.027). Hoehn and Yahr scores and ADL scores in the “on” and “off” states did not change, nor did the mean MMSE score. Weight gain occurred in the year after surgery, from (mean) 75.8 kg to 78.5 kg (p = 0.028). Duration of daily wearing off episodes was reduced by 69%. Dyskinesia severity was reduced by 60%. Drug requirements (in levodopa equivalents) declined by 30%.
Conclusions: The 30% improvement in UPDRS motor scores was a more modest result than previously reported. DBS did not improve functional capacity independent of drug use. Its chief benefits were reduction in wearing off duration and dyskinesia severity.
- ADL, activities of daily living
- DBS, deep brain stimulation
- MMSE, mini-mental state examination
- STN, subthalamic nucleus
- UPDRS, unified Parkinson’s disease rating scale
Competing interests: none declared