l-Dopa/carbidopa intestinal gel and subthalamic nucleus stimulation: Effects on cognition and behavior

Personalized Medicine in Parkinson's Disease: New Options for Advanced Treatments

Parkinson’s disease (PD) presents varying motor and non-motor features in each patient owing to their different backgrounds, such as age, gender, genetics, and environmental factors. Furthermore, in the advanced stages, troublesome symptoms vary between patients due to motor and non-motor complications. The treatment of PD has made great progress over recent decades and has directly contributed to an improvement in patients’ quality of life, especially through the progression of advanced treatment. Deep brain stimulation, radiofrequency, MR–guided focused ultrasound, gamma knife, levodopa-carbidopa intestinal gel, and apomorphine are now used in the clinical setting for this disease. With multiple treatment options currently available for all stages of PD, we here discuss the most recent options for advanced treatment, including cell therapy in advanced PD, from the perspective of personalized medicine.

An Update on Medical and Surgical Treatments of Parkinson's Disease

Parkinson’s disease (PD) is characterized by degeneration of dopaminergic neurons in the substantia nigra pars compacta and other neuronal populations. The worldwide prevalence of PD is over 7 million and has been increasing more rapidly than many other neurodegenerative disorders. PD symptoms can be broadly divided into motor (slowness, stiffness, tremor) and non-motor symptoms (such as depression, dementia, psychosis, orthostatic hypotension). Patients can also have prodromal symptoms of rapid eye movement sleep behavior disorder, hyposmia, and constipation. The diagnosis of PD is mainly clinical, but dopamine transporter single-photon emission computed tomography can improve the accuracy of the diagnosis. Dopamine based therapies are used for the treatment of motor symptoms. Non-motor symptoms are treated with other medications such as selective serotonin reuptake inhibitors (depression/anxiety), acetylcholinesterase inhibitors (dementia), and atypical antipsychotics (psychosis). Patients with motor fluctuations or uncontrolled tremor, benefit from deep brain stimulation. Levodopa-carbidopa intestinal gel is an alternative to deep brain stimulation for uncontrolled motor fluctuations. Rehabilitative therapies such as physical, occupational, and speech therapy are important during all stages of the disease. Management of PD is complex but there have been significant advancements in the treatment of motor and non-motor symptoms over the past few years. This review discusses the updates in the medical and surgical management of PD.

Translating Evidence to Advanced Parkinson's Disease Patients: A Systematic Review and Meta-Analysis

In the advanced stages of Parkinson's disease (PD), patients frequently experience disabling motor complications. Treatment options include deep brain stimulation (DBS), levodopa‐carbidopa intestinal gel (LCIG), and continuous subcutaneous apomorphine infusion (CSAI). Choosing among these treatments is influenced by scientific evidence, clinical expertise, and patient preferences. To foster patient engagement in decision‐making among the options, scientific evidence should be adjusted to their information needs. We conducted a systematic review from the patient perspective. First, patients selected outcomes for a treatment choice: quality of life, activities of daily living, ON and OFF time, and adverse events. Second, we conducted a systematic review and meta‐analysis for each treatment versus best medical treatment using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Finally, the evidence was transformed into comprehensible and comparable information. We converted the meta‐analysis results into the number of patients (per 100) who benefit clinically from an advanced treatment per outcome, based on the minimal clinically important difference and the cumulative distribution function. Although this approach allows for a comparison of outcomes across the three device‐aided therapies, they have never been compared directly. The interpretation is hindered by the relatively short follow‐up time in the included studies, usually less than 12 months. These limitations should be clarified to patients during the decision‐making process. This review can help patients integrate the evidence with their own preferences, and with their clinician's expertise, to reach an informed decision. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

Apathy Induced by Subthalamic Nucleus Deep Brain Stimulation in Parkinson's Disease: A Meta-Analysis

Apathy, the loss of motivation, is a common problem in Parkinson's disease (PD) and often observed following deep brain stimulation (DBS) of the subthalamic nucleus (STN). The aim of this meta-analysis was to determine the occurrence of apathy following STN DBS in literature. Relevant articles were searched in PubMed/Medline, SCOPUS, EMBASE, and Web of Sciences electronic databases. Studies were included if they reported apathy scores pre- and post-DBS or the cross-sectional difference between PD patients receiving STN DBS and patients receiving medication only. Thirty-three articles were included in the meta-analyses from 6,658 screened articles by two authors independently. A total of 1,286 patients were included with a mean age (±standard deviation [SD]) of 58.4 ± 8.5 years and a disease duration of 11.0 ± 5.8 years. The apathy score measured by means of the Apathy Evaluation Scale (AES), Starkstein Apathy Scale (SAS), and the Lille Apathy Rating Scale (LARS) was significantly higher after DBS than pre-operatively (g = 0.34, 95% confidence interval [CI] = 0.19-0.48, P < 0.001). An equal, significant difference in severity of apathy was found between STN DBS and medication only (g = 0.36, 95% CI = 0.03-0.65; P = 0.004). Statistical heterogeneity was moderately high, but the effects stood strong after multiple analyses and were independent of tapering off dopaminergic medication. The findings of this meta-analysis indicate that apathy is increased after STN DBS compared to the pre-operative state and to medication only (systematic review registration number: PROSPERO CRD42019133932). © 2020 Universiteit van Amsterdam. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

LCIG in treatment of non-motor symptoms in advanced Parkinson's disease: Review of literature

BACKGROUND

For managing nonmotor symptoms (NMS) in advanced Parkinson's disease (PD), levodopa-carbidopa intestinal gel (LCIG) infusion is of interest as it shows lesser plasma fluctuations of both drugs as compared to oral levodopa-carbidopa (LC).

OBJECTIVES

To highlight LCIG effect in NMS among advanced PD patients and appraise the currently available literature.

METHODS

PubMed screening (till 2020) of 184 articles was done, of which 51 were selected. Among them, 23 original articles relevant to the research question were included, of which 6 were then excluded after careful reading of full articles. The 17 relevant studies of the review provide Grade C level of evidence of efficacy.

RESULTS

LCIG is beneficial in improving or relieving various NMS especially (mood, cognition/memory, sleep, gastrointestinal symptoms, urinary symptoms, and quality of life questionnaires) in patients with advanced PD. Amelioration of motor functions or direct relations may lead to improvement in NMS PD patients using LCIG. Adverse events noted in patients treated with LCIG include pneumoperitoneum, abdominal pain, stoma infection, reversible peripheral neuropathy, local tube problems, impulse control disorder, and weight loss. Serious adverse events were mostly found to be unrelated to LCIG.

CONCLUSIONS

LCIG provides an uninterrupted intestinal levodopa infusion by percutaneous endoscopic gastrojejunostomy (PEG-J). It effectively decreases plasma fluctuations of levodopa and reduces motor instability and NMS burden in advanced PD. However, adequate dose modification and individualization of therapy are essential for optimal effect.

Comparison Between Levodopa-Carbidopa Intestinal Gel Infusion and Subthalamic Nucleus Deep-Brain Stimulation for Advanced Parkinson's Disease: A Systematic Review and Meta-Analysis

Background: Currently, some advanced treatments such as Levodopa-Carbidopa intestinal gel infusion (LCIG), deep-brain stimulation (DBS), and subcutaneous apomorphine infusion have become alternative strategies for advanced Parkinson's disease (PD). However, which treatment is better for individual patients remains unclear. This review aims to compare therapeutic effects of motor and/or non-motor symptoms of advanced PD patients between LCIG and DBS.

Methods: We manually searched electronic databases (PubMed, Embase, Cochrane Library) and reference lists of included articles published until April 04, 2019 using related terms, without language restriction. We included case-controlled cohort studies and randomized-controlled trials, which directly compared differences between LCIG and DBS. The Newcastle-Ottawa scale (NOS), proposed by the Cochrane Collaboration, was utilized to assess the quality of the included studies. Two investigators independently extracted data from each trial. Pooled standard-mean differences (SMDs) and relative risks (RRs) with 95% confidence intervals (CIs) were calculated by meta-analysis. Outcomes were grouped according to the part III and part IV of the Unified Parkinson Disease Rating Scale (UPDRS) and adverse events. We also descriptively reviewed some data, which were unavailable for statistical analysis.

Results: This review included five cohort trials of 257 patients for meta-analysis. There were no significant differences between LCIG and subthalamic nucleus deep-brain stimulation (STN-DBS) on UPDRS-III and adverse events comparisons: UPDRS-III (pooled SMDs = 0.200, 95% CI: −0.126–0.527, P = 0.230), total adverse events (pooled RRs = 1.279, 95% CI: 0.983–1.664, P = 0.067), serious adverse events (pooled RRs = 1.539, 95% CI: 0.664–3.566, P = 0.315). Notably, the improvement of UPDRS-IV was more significant in STN-DBS groups: pooled SMDs = 0.857, 95% CI: 0.130–1.584, P = 0.021. However, the heterogeneity was moderate for UPDRS-IV (I² = 73.8%).

Conclusion: LCIG has comparable effects to STN-DBS on motor function for advanced PD, with acceptable tolerability. More large, well-designed trials are needed to assess the comparability of LCIG and STN-DBS in the future.

Levodopa-Carbidopa Intestinal Gel in Parkinson's Disease: A Systematic Review and Meta-Analysis

Background: Levodopa has been widely used and regarded as the most effective therapy for Parkinson's disease (PD), but long-term treatment with oral levodopa may result in motor fluctuations and involuntary movements (dyskinesias). There is evidence to suggest that Continuous infusion of levodopa-carbidopa intestinal gel (LCIG) can effectively manage motor and non-motor complications in PD, but clinical studies investigating this have yielded inconsistent results. This systematic review and meta-analysis was performed to examine the efficacy and safety of LCIG for patients with PD.

Methods: A systematic search was conducted to retrieve published data in the EMBASE, PubMed, and the Cochrane Library up to March 2018. Both efficiency and safety of LCIG were analyzed using pooled standardized mean differences (SMDs) or odds ratio (ORs) with 95% confidence interval (CIs).

Results: Eight trials with 384 PD patients were included in the present study. Compared with the control group, LCIG significantly decreased off-time (SMD, −1.19; 95% CI, −2.25 to −0.12; p = 0.003) and increased on-time without troublesome dyskinesia (SMD, 0.55; 95% CI, 0.20 to 0.90; p = 0.002). However, no significant difference of LCIG was found in on-time with troublesome dyskinesia. There were no significant differences in UPDRS, Hoehn & Yahr and PDQ-39 scores. Besides, no significant differences in the drop-out and adverse effects.

Conclusions: Continuous delivery of LCIG may offer a promising option for PD patients. More randomized double-blind controlled studies with large sample sizes were needed to further confirm the efficacy and safety of LCIG for PD patients.

l-Dopa/carbidopa intestinal gel and subthalamic nucleus stimulation: Effects on cognition and behavior

OBJECTIVE

In Parkinson's disease (PD), effects on behavior and cognition of levodopa/carbidopa intestinal gel (LCIG) and subthalamic stimulation (STN-DBS) and their practical consequences remain controversial. This study was designed to analyze the possible effects of these therapies on cognition and behavior after 1 year follow-up.

METHODS

This was an open-label, nonrandomized prospective study for pre- and postintervention analyses. Twenty-four patients were considered eligible to be candidates for complex therapies such as STN-DBS or LCIG; 23 patients treated with standard medication were included as controls. Several cognitive, behavioral, and motor scales were administered before and at 6 and 12 months after the intervention.

RESULTS

Patients treated with LCIG experienced significant improvement in specific neuropsychological functions when compared with patients receiving STN-DBS and conventional medical treatment after 1 year from the onset of the intervention. In this study, no significant cognitive or behavioral changes occurred in patients treated with subthalamic stimulation when compared to patients receiving conventional medical treatment at 1 year follow-up.

CONCLUSIONS

Patients treated with LCIG may significantly improve some specific neuropsychological functions when compared with patients receiving STN-DBS and with patients receiving conventional medical treatment after 1 year from the intervention; there are not significant cognitive or behavioral changes in patients treated with STN-DBS when compared to PD patients receiving conventional medical treatment after 1 year from the intervention. The outcomes showed in the study can help to the selection of the appropriate candidates for STN-DBS and LCIG.