Long-term outcome of subthalamic nucleus DBS in Parkinson's disease: From the advanced phase towards the late stage of the disease?

Abstract

Background: Deep Brain Stimulation of the Subthalamic Nucleus (STN-DBS) is an effective treatment for Parkinson's disease (PD), but only few studies investigated its long-term efficacy. Furthermore, little is known about the role of PD-subtype on STN-DBS long-term outcome.Objective: To report the results of a long-term follow-up (mean 11 years, range 10-13) on 26 patients bilaterally implanted in two centres. Methods:Patients were assessed preoperatively and 1, 5 and 11 years after the implant by the Unified Parkinson's Disease Rating Scale (UPDRS) and a battery of neuropsychological tests. Stimulation parameters, drugs dosages, non-motor symptoms and adverse events were also recorded.Results: At 11 years, stimulation significantly improved the motor symptoms by 35.8%, as compared to the preoperative off-state. Motor complications were well controlled, with a 84.6% improvement of dyskinesias and a 65.8% improvement of motor fluctuations. Despite this, the UPDRS-II-on score worsened by 88.5%, mainly for the worsening of poorly levodopa-responsive symptoms. More than 70% of the patients performed in the normal range in most of the neuropsychological tests, despite the development of dementia in 22.7%. Age at disease onset, axial subscore in off-condition and presence of REM behaviour disorder at baseline were found to be associated with a higher risk of developing disability over time. Conclusions:Our study confirms the long-term safety and efficacy of STN-DBS in PD. Nevertheless, the functionality of patients worsens over time, mainly for the onset and progression of levodopa-resistant and non-motor symptoms. The role of PD-subtype seems to be relevant in the long-term outcome.

Genetic and Clinical Predictors of Deep Brain Stimulation in Young‐Onset Parkinson's Disease

“…Studies are needed to assess mutation prevalence in subjects with an AAO ≥ 51 years but < 70 years, because DBS is considered in individuals up to age 75 years. 21,23 Also, only patients with MMSE scores > 24 were included in the study; thus, it is possible that mutation carriers who developed dementia after DBS were missed in our cohort. A prospective study is needed to capture the prevalence of mutation carriers in the DBS candidate population and the impact of DBS in these individuals.…”

Improving outcomes of subthalamic nucleus deep brain stimulation in Parkinson’s disease

“…The most common side effects are speech problems (hypophonia, dysarthria) and dystonias (in particular, blepharospasm and eyelid opening apraxia). Others, such as freezing or unsteadiness of gait, or weight gain, are the result of chronic stimulation and disease progression [57]. Adaptive DBS may be the most promising approach to reduce the incidence of these problems.…”

“…In addition, transitioning image acquisition from the pre-operative phase and into the operating room is already promising to fundamentally change DBS surgery by allowing real-time targeting which may eventually obviate the need for extensive intraoperative physiological mapping. This will, in turn, lead to a decrease in operative time and the associated morbidity [57]. Indeed, targeting based solely on image guidance has become routine practice in some centers [51,61].…”

Rescue Procedures after Suboptimal Deep Brain Stimulation Outcomes in Common Movement Disorders

“…Studies have demonstrated a notable improvement in quality of life, motor scores, and a reduction of wearing off in patients who have received DBS [17,18,19]. Overall benefits have been maintained for up to 11 years according to long-term follow-up studies [20,21,22] although there is some concern that any initial benefit in gait or posture may deteriorate more quickly [23]. …”