Deep Brain Stimulation Impact on Social and Occupational Functioning in Parkinson's Disease with Early Motor Complications

Possible improvement of social adjustment after subthalamic deep brain stimulation in people with Parkinson's disease? A systematic review and meta-analysis

Interactions with others need social adjustment (i.e., the constant accommodation to changing social situations). Mixed evidence indicates positive as well as negative changes in social adjustment after subthalamic nucleus deep brain stimulation (STN-DBS) in people with Parkinson's Disease (PwPD). To date, however, no meta-analysis of these changes exists. Thus, the study aim was to review evidence of the effects of STN-DBS on social adjustment in PwPD. For this purpose, a systematic literature search in MEDLINE was conducted. The meta-analysis was performed using a random effects model and standardized mean differences (SMDs) with 95% confidence intervals (CIs). The MINORS tool was used to assess the methodological quality of the studies. The initial literature search identified 13,124 articles, of which 1,550 full texts were assessed for eligibility. Eight studies were finally included; for seven articles sufficient data for a meta-analysis was available. Most studies found mild impairment in social adjustment impairment pre-surgery. The meta-analysis revealed no significant changes but a statistical trend towards improvement in social adjustment up to six months (SMD = 0.25; 95%CI=-0.03,0.53; P = 0.08) and over 12 months (SMD = 0.26; 95%CI=-0.03,0.55; P = 0.07) post-surgery. Methodological quality was moderate in 87.5% of the studies and good in 12.5%. While mild impairment in social adjustment pre-surgery was reported in most studies, the data indicate that STN-DBS might yield beneficial effects toward this outcome. However, not enough data yet exists to draw firm conclusions. As a crucial skill for everyday functioning, social adjustment should be more often defined as an outcome in STN-DBS trials in PwPD and should be considered in clinical routines.

Medical, surgical, and physical treatments for Parkinson's disease

Although dopamine replacement therapy remains a core component of Parkinson's disease treatment, the onset of motor fluctuations and dyskinetic movements might require a range of medical and surgical approaches from a multidisciplinary team, and important new approaches in the delivery of dopamine replacement are becoming available. The more challenging, wide range of non-motor symptoms can also have a major impact on the quality of life of a patient with Parkinson's disease, and requires careful multidisciplinary management using evidence-based knowledge, as well as appropriately tailored strategies according to the individual patient's needs. Disease-modifying therapies are urgently needed to prevent the development of the most disabling refractory symptoms, including gait and balance difficulties, cognitive impairment and dementia, and speech and swallowing impairments. In the third paper in this Series, we present the latest evidence supporting the optimal treatment of Parkinson's disease, and describe an expert approach to many aspects of treatment choice where an evidence base is insufficient.

Time to workforce exit after a Parkinson's disease diagnosis

The impact of Parkinson's disease (PD) on workforce participation has received little attention even though demographic, lifestyle, and political changes together will result in an increased burden of PD on the working-age population. In this study, we investigate workforce survival after a PD diagnosis, as well as what demographic factors that are associated with workforce survival. As an exploratory outcome, we investigate workforce survival in persons with and without device-aided treatment (DAT). This is a nested case-cohort study based on Swedish national data from 2001-2016. Controls were matched on year of birth, sex, and municipality of residence. The used registers contain data on demographics, social insurance, in- and outpatient visits, filled drug prescriptions, and cause of death on the person-level. A total of 4781 persons with PD and 23,905 controls were included. The median survival until all-cause workforce exit was 43 months among persons that were workforce-active at the time of PD diagnosis, compared to 66 months in non-PD controls. Being female, ≥50 years old at diagnosis, or having a lower education were contributing factors to health-related workforce exit. Persons receiving DAT during follow-up exhibited shorter workforce survival than controls. However, this needs further investigation, particularly as patients have generally already left the workforce at the time for start of DAT. It is evident that PD has grave negative effects on workforce participation. Thus, supportive measures need to start at an early stage after diagnosis, and the development of new interventions is urgently needed.

Perceived social support declines after deep brain stimulation surgery in patients with Parkinson's disease

INTRODUCTION

The Social Provisions Scale (SPS) measures a person's perceived social support. We evaluated the perceived social support in Parkinson's disease (PD) patients before and after subthalamic nucleus (STN) deep brain stimulation (DBS) and its impact on clinical outcomes following DBS.

METHODS

We analyzed 55 PD patients who underwent STN DBS surgery and completed the SPS, PDQ-39, and MDS-UPDRS Parts I-IV before and 6-12 months after surgery. Some patients also completed global cognitive, mood and apathy scales. Caregivers completed the CBI at each visit. Linear regression models and linear mixed models evaluated the association between the SPS baseline score, MDS-UPDRS and PDQ-39 scores, the association between MDS-UPDRS, CBI and the SPS follow-up score, and the association between SPS, global cognition and other psychological variables.

RESULTS

DBS implantation improved MDS-UPDRS I-IV and PDQ-39 scores. Perceived social support declined after DBS (baseline SPS total 82.55 ± 7.52 vs. follow-up SPS total 78.83 ± 9.02, p = 0.0001). Baseline SPS total score was not significantly associated with the MDS-UPDRS or PDQ-39 scores at follow-up. MDS-UPDRS scores and the CBI at follow-up had no significant association with SPS total score at follow-up. Measures of global cognition, mood and apathy were associated with the SPS before and after DBS, and the association was independent of STN DBS.

CONCLUSION

After STN DBS, PD patients experienced a decrease in perceived social support, but baseline perceived social support did not impact clinical outcomes. It is important to further identify factors that may contribute to this perception of worsened social support.

Advances in DBS Technology and Novel Applications: Focus on Movement Disorders

PURPOSE OF REVIEW

Deep brain stimulation (DBS) is an established treatment in several movement disorders, including Parkinson's disease, dystonia, tremor, and Tourette syndrome. In this review, we will review and discuss the most recent findings including but not limited to clinical evidence.

RECENT FINDINGS

New DBS technologies include novel hardware design (electrodes, cables, implanted pulse generators) enabling new stimulation patterns and adaptive DBS which delivers potential stimulation tailored to moment-to-moment changes in the patient's condition. Better understanding of movement disorders pathophysiology and functional anatomy has been pivotal for studying the effects of DBS on the mesencephalic locomotor region, the nucleus basalis of Meynert, the substantia nigra, and the spinal cord. Eventually, neurosurgical practice has improved with more accurate target visualization or combined targeting. A rising research domain emphasizes bridging neuromodulation and neuroprotection. Recent advances in DBS therapy bring more possibilities to effectively treat people with movement disorders. Future research would focus on improving adaptive DBS, leading more clinical trials on novel targets, and exploring neuromodulation effects on neuroprotection.

Investigation of Magnetoelectric Sensor Requirements for Deep Brain Stimulation Electrode Localization and Rotational Orientation Detection

Correct position and orientation of a directional deep brain stimulation (DBS) electrode in the patient’s brain must be known to fully exploit its benefit in guiding stimulation programming. Magnetoelectric (ME) sensors can play a critical role here. The aim of this study was to determine the minimum required limit of detection (LOD) of a ME sensor that can be used for this application by measuring the magnetic field induced by DBS. For this experiment, a commercial DBS system was integrated into a head phantom and placed inside of a state-of-the-art Superconducting Quantum Interference Device (SQUID)-based magnetoencephalography system. Measurements were performed and analyzed with digital signal processing. Investigations have shown that the minimum required detection limit depends on various factors such as: measurement distance to electrode, bandwidth of magnetic sensor, stimulation amplitude, stimulation pulse width, and measurement duration. For a sensor that detects only a single DBS frequency (stimulation frequency or its harmonics), a LOD of at least 0.04 pT/Hz0.5 is required for 3 mA stimulation amplitude and 60 μs pulse width. This LOD value increases by an order of magnitude to 0.4 pT/Hz0.5 for a 1 kHz, and by approximately two orders to 3 pT/Hz0.5 for a 10 kHz sensor bandwidth. By averaging, the LOD can be reduced by at least another 2 orders of magnitude with a measurement duration of a few minutes.