Safety of Levodopa-Carbidopa Intestinal Gel Treatment in Patients with Advanced Parkinson's Disease Receiving ≥2000 mg Daily Dose of Levodopa

An Artificial Neural Network Predicts Gender Differences of Motor and Non-Motor Symptoms of Patients with Advanced Parkinson's Disease under Levodopa-Carbidopa Intestinal Gel

Background and Objectives: Currently, no tool exists to predict clinical outcomes in patients with advanced Parkinson's disease (PD) under levodopa-carbidopa intestinal gel (LCIG) treatment. The aim of this study was to develop a novel deep neural network model to predict the clinical outcomes of patients with advanced PD after two years of LCIG therapy. Materials and Methods: This was a longitudinal, 24-month observational study of 59 patients with advanced PD in a multicenter registry under LCIG treatment from September 2019 to September 2021, including 43 movement disorder centers. The data set includes 649 measurements of patients, which make an irregular time series, and they are turned into regular time series during the preprocessing phase. Motor status was assessed with the Unified Parkinson's Disease Rating Scale (UPDRS) Parts III (off) and IV. The NMS was assessed by the NMS Questionnaire (NMSQ) and the Geriatric Depression Scale (GDS), the quality of life by PDQ-39, and severity by Hoehn and Yahr (HY). Multivariate linear regression, ARIMA, SARIMA, and Long Short-Term Memory-Recurrent NeuralNetwork (LSTM-RNN) models were used. Results: LCIG significantly improved dyskinesia duration and quality of life, with men experiencing a 19% and women a 10% greater improvement, respectively. Multivariate linear regression models showed that UPDRS-III decreased by 1.5 and 4.39 units per one-unit increase in the PDQ-39 and UPDRS-IV indexes, respectively. Although the ARIMA-(2,0,2) model is the best one with AIC criterion 101.8 and validation criteria MAE = 0.25, RMSE = 0.59, and RS = 0.49, it failed to predict PD patients' features over a long period of time. Among all the time series models, the LSTM-RNN model predicts these clinical characteristics with the highest accuracy (MAE = 0.057, RMSE = 0.079, RS = 0.0053, mean square error = 0.0069). Conclusions: The LSTM-RNN model predicts, with the highest accuracy, gender-dependent clinical outcomes in patients with advanced PD after two years of LCIG therapy.

Starting with 24-h levodopa carbidopa intestinal gel at initiation in a large cohort of advanced Parkinson's disease patients

Continuous intra-jejunal infusion of levodopa-carbidopa intestinal gel (LCIG) is a long-term proven and effective treatment in advanced Parkinson's Disease (APD). Efficacy and safety of 16-h administration of LCIG has already been established. Additional benefits of 24-h LCIG administration have been reported in several case series and small clinical studies. The aim of this retrospective study was to compare the characteristics of patients who needed 24-h LCIG from the beginning of the DAT (device-aided treatment) with those who remained with the standard 16-h LCIG treatment and to identify particular motives if any. We initiated LCIG in 150 patients out of which in case of 62 patients (41,3%) due to unsatisfactory initial clinical benefits continuous 24-h LCIG was deemed necessary. Despite the subjective complaints and more severe clinical condition, at baseline evaluation we found statistically significant differences between 16-h LCIG cohort and 24-h LCIG cohort only in case of incidence of freezing (47% vs 65%, p = 0.03) and sudden off (32% vs 48%, p = 0.04). Wake hours/daytime LCIG does not always sufficiently improve the patient's quality of life in some patients due to persistent nighttime troublesome symptoms. Instead of labeling the patient as a non-responder, it is worth trying the 24-h LCIG dosage in a carefully selected group of patients, as there is currently no consensus on reliable criteria that serve the decision in these patients.

Levodopa-Carbidopa Intestinal Gel in Advanced Parkinson's Disease: Observations and Dilemmas after 10 Years of Real-Life Experience

Advanced Parkinson's disease (APD) cannot be treated efficiently using the classical medications however, in recent decades invasive therapeutical methods were implemented and confirmed as effective. One of these methods makes it possible to continue the levodopa (LD) supplementation as a gel administered directly into the upper intestine. However, there are a number of unanswered questions regarding this method. Therefore, we retrospectively analyzed a 10-year period of selected patients that were treated with levodopa/carbidopa intestinal gel (LCIG). We included all APD patients with motor fluctuations and dyskinesia at presentation. LCIG treatment was started in 150 patients: on average these patients received LD for 10.6 ± 4.4 years with a frequency of 5.2 ± 1.0/day until the introduction of LCIG. The estimated and the real LCIG dose differed significantly (mean: 1309 ± 321 mg vs. 1877 ± 769 mg). The mean duration of LCIG administration was 19.8 ± 3.6 h, but in a number of 62 patients we had to administer it for 24 h, to maximize the therapeutic benefit. A carefully and individually adjusted LCIG treatment improves the quality of life of APD patients, but questions remain unresolved even after treating a large number of patients. It is important to share the ideas and observations based on the real-life experience related to the optimal timing, the appropriate dose and duration of administration of the LCIG.

Polyneuropathy monitoring in Parkinson's disease patients treated with levodopa/carbidopa intestinal gel

OBJECTIVES

Levodopa-carbidopa-intestinal-gel (LCIG) infusion is an effective treatment for advanced PD with motor fluctuations. Polyneuropathy occurs as a complication in 10-15% of patients. We wanted to assess the frequency of polyneuropathy in Finnish advanced Parkinson's disease (PD) patients with continuous LCIG infusion, and the value of different clinical monitoring parameters during follow-up.

MATERIALS AND METHODS

Patient records of PD patients started on LCIG infusion at Helsinki University Hospital who received nerve conduction studies at baseline and 6 months after treatment initiation were reviewed for epidemiological information, mini mental state examination, baseline and 6 months' UPRDS-III, weight, body mass index, levodopa dose (LD), plasma homocysteine levels, folate, vitamin B6 and B12.

RESULTS

Out of 19 patients (n = 6 on B-vitamin substitution), two (10.5%) developed new-onset polyneuropathy after initiation of LCIG therapy (n = 0 with vitamin substitution). Neuropathy was associated with significant weight loss (BMI reduction > 1.5), but not with other monitoring parameters. Homocysteine rose significantly in patients not substituted with B-vitamin complex, but not in patients with B-vitamin substitution. Homocysteine changes correlated with LD changes in the absence of vitamin B substitution. After oral B-vitamin substitution, both patients' polyneuropathy remained electrophysiologically and clinically stable.

CONCLUSIONS

Rates of polyneuropathy in Finnish PD patients with LCIG treatment are comparable to previous studies. Patients' weight should be included in regular follow up monitoring and can be used for patient self-monitoring. Vitamin B substitution appears to reduce coupling between levodopa dose and homocysteine and may be useful to prevent polyneuropathy related to LCIG.

Management Challenges of Severe, Complex Dyskinesia. Data from a Large Cohort of Patients Treated with Levodopa-Carbidopa Intestinal Gel for Advanced Parkinson's Disease

BACKGROUND

In the advanced stages of Parkinson's disease (APD), complex forms of dyskinesia may severely impair the patient's quality of life.

OBJECTIVE

In the present study, we aimed to analyze the evolution under LCIG therapy of the most important motor fluctuations and complex disabling dyskinesias, including diphasic dyskinesia.

METHODS

In this retrospective study, we analyzed the characteristics of patients with APD who had at least 30 min of diphasic dyskinesia (DID) in 3 consecutive days, were considered responders and were treated with LCIG in our clinic. Patients were evaluated before and after PEG and at 6, 12 and 18 months, when the changes in the therapy were recorded, and they completed a 7-point Global Patient Impression of Improvement (PGI-I) scale.

RESULTS

Forty patients fulfilled the inclusion criteria-out of which, 34 performed all visits. There was a substantial difference between the calculated and real LCIG (1232 ± 337 mg vs. 1823 ± 728 mg). The motor fluctuations and most dyskinesias improved significantly after starting LCIG, but an increasing number of patients needed longer daily administrations of LCIG (24 instead of 16 h).

CONCLUSIONS

Patients with APD with complex dyskinesias must be tested in dedicated hospitals, and they need a special therapeutic approach. The properly adapted LCIG treatment regarding the dose and time of administration completed with well-selected add-on medication should offer improvement for patients who want to or can only choose this DAT vs. others.

The Choice Between Advanced Therapies for Parkinson's Disease Patients: Why, What, and When?

When oral dopaminergic medication falls short in the treatment of Parkinson's disease, patients are left with motor response fluctuations and dyskinesias that may have a large impact on functioning in daily life. They may benefit from one of the currently available advanced treatments, namely deep brain stimulation, continuous levodopa-carbidopa intestinal gel, and continuous subcutaneous apomorphine infusion. The indication, choice between the separate advanced treatments and the timing can be challenging and will be discussed against the background of the progressive nature of the disease, the heterogeneity of disease manifestation and variable patient characteristics.