DBS Improves Survival in Severe Parkinson's Disease
Objectives Levodopa and other dopaminergic treatments have not had the expected effect on survival in Parkinson's disease (PD). Bilateral subthalamic nucleus deep brain stimulation (STN-DBS) has been shown to improve motor function, motor fluctuations, health-related quality of life, and to reduce medication usage and drug-induced dyskinesia in patients with severe PD refractory to medical therapy. Little however, has been described on the impact of STN-DBS on the survival of these patients. We aim in this study to examine the impact of STN-DBS on the survival of patients with severe PD.
Methods Patients who were eligible for STN-DBS were given the choice of undergoing surgery or continuing on medical treatment. Those who exercised patient choice and preferred to continue with medical treatment formed a control population. All eligible patients seen in a 10-year period are included in this study. Our primary outcome measure is a difference in mortality between the two groups with a secondary measure of admission rates to residential (nursing home) care.
Results 106 patients underwent STN-DBS, and 41 patients exercised patient choice and declined the procedure. The two groups were matched for age, gender, ethnicity, duration of disease, rates of pre-existing depression and Levodopa equivalent doses of anti-Parkinson's medications taken. Patients undergoing STN-DBS had significantly longer survival and were significantly less likely to be admitted to a residential care home than those managed purely medically. The statistical significance of these findings persisted after adjusting for potential confounding factors (survival: p=0.002, HR 0.29 (0.13 to 0.64) (residential care home admission: OR: 0.1 (95% CI 0.0 to 0.3; p<0.001).
Interpretation We show for the first time that there is a survival advantage of DBS surgery in advanced PD. The effect of potential bias factors is examined. The survival advantage may arise for several postulated reasons, ranging from improvement in axial functions, such as swallowing, to some as yet unrecognised benefit of reduction in dopaminergic medication. These findings are of great interest to both patients with PD and the health professionals considering the treatment options for patients with severe PD.
Parkinson's disease (PD) is a major cause of neurological disability in the UK, with a prevalence of 100–180 per 100 000 and an increasing incidence with age. Medical treatment of the motor manifestations is very successful in the early stages of the disease, but in advanced disease, motor fluctuations comprising alternating dyskinesia and akinesia become suboptimally controlled with drug changes.
Bilateral subthalamic nucleus deep brain stimulation (STN-DBS) using high-frequency continuous electrical stimulation to the subthalamic nucleus through a surgically implanted device, has become established as an effective treatment for the motor symptoms of patients with advanced PD refractory to medical management.
Improvements have been demonstrated in Motor function, Quality of life (using generic scales such as health-related quality of life and disease-specific ones such as PDQ 39), and reductions in motor fluctuation, reduced medication usage and, therefore, alleviation of drug-induced dyskinesia.
Life expectancy is decreased in PD with an OR of 2.56 (95% CI 2.46 to 2.66; p<0.001), and the advent of medical treatments does not appear to have altered either mortality from the condition or significantly delayed the onset of non-motor features of the disease.
The impact of STN DBS on survival has not previously been studied. In this study, we examined the impact of STN-DBS on the survival of patients with severe PD in a single institution.
Abstract and Introduction
Abstract
Objectives Levodopa and other dopaminergic treatments have not had the expected effect on survival in Parkinson's disease (PD). Bilateral subthalamic nucleus deep brain stimulation (STN-DBS) has been shown to improve motor function, motor fluctuations, health-related quality of life, and to reduce medication usage and drug-induced dyskinesia in patients with severe PD refractory to medical therapy. Little however, has been described on the impact of STN-DBS on the survival of these patients. We aim in this study to examine the impact of STN-DBS on the survival of patients with severe PD.
Methods Patients who were eligible for STN-DBS were given the choice of undergoing surgery or continuing on medical treatment. Those who exercised patient choice and preferred to continue with medical treatment formed a control population. All eligible patients seen in a 10-year period are included in this study. Our primary outcome measure is a difference in mortality between the two groups with a secondary measure of admission rates to residential (nursing home) care.
Results 106 patients underwent STN-DBS, and 41 patients exercised patient choice and declined the procedure. The two groups were matched for age, gender, ethnicity, duration of disease, rates of pre-existing depression and Levodopa equivalent doses of anti-Parkinson's medications taken. Patients undergoing STN-DBS had significantly longer survival and were significantly less likely to be admitted to a residential care home than those managed purely medically. The statistical significance of these findings persisted after adjusting for potential confounding factors (survival: p=0.002, HR 0.29 (0.13 to 0.64) (residential care home admission: OR: 0.1 (95% CI 0.0 to 0.3; p<0.001).
Interpretation We show for the first time that there is a survival advantage of DBS surgery in advanced PD. The effect of potential bias factors is examined. The survival advantage may arise for several postulated reasons, ranging from improvement in axial functions, such as swallowing, to some as yet unrecognised benefit of reduction in dopaminergic medication. These findings are of great interest to both patients with PD and the health professionals considering the treatment options for patients with severe PD.
Introduction
Parkinson's disease (PD) is a major cause of neurological disability in the UK, with a prevalence of 100–180 per 100 000 and an increasing incidence with age. Medical treatment of the motor manifestations is very successful in the early stages of the disease, but in advanced disease, motor fluctuations comprising alternating dyskinesia and akinesia become suboptimally controlled with drug changes.
Bilateral subthalamic nucleus deep brain stimulation (STN-DBS) using high-frequency continuous electrical stimulation to the subthalamic nucleus through a surgically implanted device, has become established as an effective treatment for the motor symptoms of patients with advanced PD refractory to medical management.
Improvements have been demonstrated in Motor function, Quality of life (using generic scales such as health-related quality of life and disease-specific ones such as PDQ 39), and reductions in motor fluctuation, reduced medication usage and, therefore, alleviation of drug-induced dyskinesia.
Life expectancy is decreased in PD with an OR of 2.56 (95% CI 2.46 to 2.66; p<0.001), and the advent of medical treatments does not appear to have altered either mortality from the condition or significantly delayed the onset of non-motor features of the disease.
The impact of STN DBS on survival has not previously been studied. In this study, we examined the impact of STN-DBS on the survival of patients with severe PD in a single institution.