Fluctuating functions related to quality of life in advanced Parkinson disease: effects of duodenal levodopa infusion

Patient and caregiver outcomes with levodopa-carbidopa intestinal gel in advanced Parkinson’s disease

Levodopa-carbidopa intestinal gel (LCIG) has shown to be efficacious in motor and non-motor symptoms (NMS). Nevertheless, studies with patient Quality of Life (QoL) as a primary endpoint are scarce. To assess the effect of LCIG on Advanced Parkinson’s Disease (APD) patients QoL. Secondarily, the impact on motor symptoms and NMS, emotional well-being, treatment satisfaction, and caregiver QoL, stress, disease burden, anxiety, depression, and work impairment were also investigated. In this prospective, 6-month multicenter postmarketing observational study, LCIG was administered to 59 patients with APD. Endpoints were assessed using validated scales and questionnaires. LCIG significantly improved patient QoL (PDQ-39 mean change ± standard deviation from baseline, −12.8 ± 14.6; P < 0.0001), motor symptoms (UPDRS-III in “On,” −6.5 ± 11.8; P = 0.0002), NMS (NMSS, −35.7 ± 31.1; P < 0.0001), mood (Norris/Bond-Lader VAS, −6.6 ± 21.1; P = 0.0297), fatigue (PFS-16, −0.6 ± 1.0; P = 0.0003), depression (BDI-II, −5.1 ± 9.4; P = 0.0002), anxiety (BAI, −6.2 ± 9.6; P < 0.0001), and patient treatment satisfaction (SATMED-Q, 16.1 ± 16.8; P < 0.0001). There were significant correlations between the change from baseline to 6 months between PDQ-39 and UPDRS-IV, NMSS, BAI, BDI-II, AS, and PFS-16 scores, and Norris/Bond-Lader alertness/sedation factor. Caregiver anxiety also improved (Goldberg anxiety scale, −1.1 ± 1.0; P = 0.0234), but the clinical relevance of this finding is questionable. The serious adverse events reported were similar to those previously described for LCIG. In patients with APD, LCIG improves QoL, motor symptoms and NMS, emotional well-being, and satisfaction with the treatment. Improvement in patient QoL is associated with improvements in motor complications, NMS, anxiety, depression, apathy and fatigue. Improvements in patients’ QoL does not correspond with improvements in caregivers’ QoL or burden.

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

Intrajejunal vs oral levodopa-carbidopa therapy in Parkinson disease: A retrospective cohort study

Levodopa-carbidopa intestinal gel (LCIG) is a method of continuous administration of levodopa - the standard treatment in Parkinson disease (PD, a neurodegenerative disorder characterized by resting tremor, rigidity, gait impairment, and bradykinesia), thought to reduce the short-life and pulsatile problems of oral administration. We aimed to study the effects of Levodopa-Carbidopa therapy in 2 separate groups: one with intrajejunal administration of Levodopa-Carbidopa gel and the second with oral therapy.We performed an observational retrospective Romanian cohort study on 61 patients diagnosed with PD patients, with Hoehn and Jahr 3 and 4 stages, recruited from a single regional tertiary center in Cluj-Napoca, Romania, between 2009 and 2019.The mean adjusted UPDRS III (and similarly for UPDRS II) improved in the LCIG compared to the oral therapy group with 15.6 (95% CI 12.0-19.2, P < .001), and with 18.4 (95% CI 13.8-22.9, P < .001), stratified for the Hoehn and Jahr stages 3 and 4. There was a 41.7% (10) reduction in dyskinesia, and 29.2% reduction in wearing off/on-off at 1 year in the LCIG group compared to 0% (0) dyskinesia reduction, and 2.7% reduction in wearing off/on-off in the oral therapy group.Continuous intrajejunal infusion of LCIG ensures a significant and clinical reduction in motor fluctuations compared to oral therapy in advanced PD, even after adjustment for important confounders.

Subclinical affective and cognitive fluctuations in Parkinson's disease: a randomized double-blind double-dummy study of Oral vs. Intrajejunal Levodopa

BACKGROUND

Chronic levodopa treatment in Parkinson's disease (PD) may promote undesirable motor and non-motor fluctuations. Compared to chronic oral levodopa treatment, continuous infusion of levodopa/carbidopa intestinal gel (LCIG) in advanced PD reduces motor fluctuations. However, differences in their effect on acute non-motor changes were not formally demonstrated.

OBJECTIVE

We performed a randomized, double-blind, double-dummy, crossover study to compare acute non-motor changes between intermittent oral immediate-release carbidopa/levodopa (LC-IR) and LCIG.

METHODS

After > 12-h OFF, thirteen PD patients chronically treated with LCIG and without history of non-motor swings, were allocated to receive first, LCIG infusion plus three oral doses of placebo, or placebo infusion plus three oral doses of LC-IR. Over-encapsulated oral medication (LC-IR or placebo) was administered every 2 h. We monitored plasmatic levels of levodopa, motor status (UPDRS-III), mood, anxiety, and frontal functions at baseline (0-h) and hourly after each oral challenge.

RESULTS

Repeated-measures ANOVAs showed significant group by treatment interaction indicating more fluctuations of levodopa plasma levels with LC-IR. No significant interactions were seen in the temporal profile of motor status, anxiety, mood and cognition. However, point-to-point parametric and nonparametric tests showed a significant more marked and more sustained improvement in anxiety scores under LCIG. A significant improvement of mood and verbal fluency was seen a + 3-h only under LCIG.

DISCUSSION

Our sample of advanced PD patients exhibited moderate but significant non-motor fluctuations. LCIG was associated with a more favorable profile of acute affective and cognitive fluctuations that was particularly expressed at the first part of the infusion curve.

Cost-utility analysis of levodopa carbidopa intestinal gel (Duodopa) in the treatment of advanced Parkinson's disease in patients in Scotland and Wales

AIMS

To carry out a cost-utility analysis comparing the cost-effectiveness of levodopa carbidopa intestinal gel (LCIG) with standard of care (SOC) in patients with advanced Parkinson's Disease (aPD) unsuitable for apomorphine or deep brain stimulation (DBS). LCIG is the only treatment option in this small, but clinically important, population.

METHODS

A Markov model with 25 disease states based on disease stage and off-time status plus death. Patients enter the model with aPD spending >50% of their waking day in the off-state. Patients progress through the model in 6-monthly cycles for 20 years to approximate lifetime treatment and capture long-term costs and effects of therapy. Inputs are based on LCIG clinical trials for clinical outcomes and health state utilities, the literature for health state transitions and use UK-based input data wherever possible (drug costs, disease/adverse event management costs, discontinuation rates, mortality rates).

LIMITATIONS

Data collection can be challenging in this small, elderly population with advanced disease, therefore some model inputs were estimated, rather than collected directly. It was assumed that a reduction in off-time was the only benefit after the first year of treatment with LCIG; this is a conservative approach, since there may be additional clinical benefits.

RESULTS

There is a considerable incremental gain in quality adjusted life years (QALYs) for patients treated with LCIG of 1.26 QALY with an associated incremental cost-effectiveness ratio (ICER) of £52,110. If the impact on caregivers is included, the ICER reduces to £47,266.

CONCLUSIONS

In cases where there is an orphan population, with no alternative treatment options, HTA assessments have a broader decision-making framework and the ICER is interpreted in this context. In the setting of a very small population, with considerable unmet need, LCIG represents value for money, as reflected by funding approval across the UK.

Using measurements from wearable sensors for automatic scoring of Parkinson's disease motor states: Results from 7 patients

The objective of this study was to investigate the validity of an objective gait measure for assessment of different motor states of advanced Parkinson's disease (PD) patients. Seven PD patients performed a gait task up to 15 times while wearing sensors on their upper and lower limbs. Each task was performed at specific points during a test day, following a single dose of levodopa-carbidopa. At the time of the tasks the patients were video recorded and three movement disorder experts rated their motor function on three clinical scales: a treatment response scale (TRS) that ranged from -3 (very bradykinetic) to 0 (ON) to +3 (very dyskinetic), a dyskinesia score that ranged from 0 (no dyskinesia) to 4 (extreme dyskinesia), and a bradykinesia score that ranged from 0 (no bradykinesia) to 4 (extreme bradykinesia). Raw accelerometer and gyroscope data of the sensors were processed and analyzed with time series analysis methods to extract features. The utilized features quantified separate limb movements as well as movement symmetries between the limbs. The features were processed with principal component analysis and the components were used as predictors for separate support vector machine (SVM) models for each of the three scales. The performance of each model was evaluated in a leave-one-patient out setting where the observations of a single patient were used as the testing set and the observations of the other 6 patients as the training set. Root mean square error (RMSE) and correlation coefficients for the predictions showed a good ability of the models to map the sensor data into the rating scales. There were strong correlations between the SVM models and the mean ratings of TRS (0.79; RMSE=0.70), bradykinesia score (0.79; RMSE=0.47), and bradykinesia score (0.78; RMSE=0.46). The results presented in this paper indicate that the use of wearable sensors when performing gait tasks can generate measurements that have a good correlation to subjective expert assessments.

Can suitable candidates for levodopa/carbidopa intestinal gel therapy be identified using current evidence?

Advanced Parkinson's disease (APD) is characterized by increased functional disability, caused by motor complications, the presence of axial symptoms, and emergent disease- and drug-related non-motor symptoms. One of the advanced therapies available is intrajejunal infusion of levodopa/carbidopa intestinal gel (LCIG); however, patient selection for this treatment is sometimes difficult, particularly because of overlapping indications with other alternatives. In recent years, strong evidence has supported the use of LCIG in treating motor fluctuations associated with APD, and several clinical studies provide emerging evidence for additional benefits of LCIG treatment in certain patients. This article provides an overview of the published literature on the benefits, limitations, and drawbacks of LCIG in relation to PD symptoms, the psychosocial impact of the disease, and the quality of life of patients, with the aim of determining candidates for whom treatment with LCIG would be beneficial. According to current evidence, patients with APD (defined as inability to achieve optimal control of the disease with conventional oral treatment), a relatively well-preserved cognitive-behavioral status, and good family/caregiver would count as suitable candidates for LCIG treatment. Contraindications in the opinion of the authors are severe dementia and active psychosis.

Verification of a Method for Measuring Parkinson's Disease Related Temporal Irregularity in Spiral Drawings

Parkinson’s disease (PD) is a progressive movement disorder caused by the death of dopamine-producing cells in the midbrain. There is a need for frequent symptom assessment, since the treatment needs to be individualized as the disease progresses. The aim of this paper was to verify and further investigate the clinimetric properties of an entropy-based method for measuring PD-related upper limb temporal irregularities during spiral drawing tasks. More specifically, properties of a temporal irregularity score (TIS) for patients at different stages of PD, and medication time points were investigated. Nineteen PD patients and 22 healthy controls performed repeated spiral drawing tasks on a smartphone. Patients performed the tests before a single levodopa dose and at specific time intervals after the dose was given. Three movement disorder specialists rated videos of the patients based on the unified PD rating scale (UPDRS) and the Dyskinesia scale. Differences in mean TIS between the groups of patients and healthy subjects were assessed. Test-retest reliability of the TIS was measured. The ability of TIS to detect changes from baseline (before medication) to later time points was investigated. Correlations between TIS and clinical rating scores were assessed. The mean TIS was significantly different between healthy subjects and patients in advanced groups (p-value = 0.02). Test-retest reliability of TIS was good with Intra-class Correlation Coefficient of 0.81. When assessing changes in relation to treatment, TIS contained some information to capture changes from Off to On and wearing off effects. However, the correlations between TIS and clinical scores (UPDRS and Dyskinesia) were weak. TIS was able to differentiate spiral drawings drawn by patients in an advanced stage from those drawn by healthy subjects, and TIS had good test-retest reliability. TIS was somewhat responsive to single-dose levodopa treatment. Since TIS is an upper limb high-frequency-based measure, it cannot be detected during clinical assessment.

Long-term safety and effectiveness of levodopa-carbidopa intestinal gel infusion

INTRODUCTION

Levodopa-carbidopa intestinal gel (LCIG) infusion has demonstrated to improve motor fluctuations. The aim of this study is to assess the long-term safety and effectiveness of LCIG infusion in advanced Parkinson's disease (PD) patients with motor fluctuations and its effect in nonmotor symptoms.

METHODS

Adverse events (AE) and their management, clinical motor, and nonmotor aspects were assessed up to 10 years. Thirty-seven patients were treated with LGIC; in three subsets of patients, specific batteries of tests were used to assess cognitive and behavior assessment for 6 months, quality of sleep for 6 months, and quality of life and caregiver burden for 1 year.

RESULTS

There was a high number of AE, but manageable, most of mild and moderate severity. All patients experienced significant improvement in motor fluctuations with a reduction in mean daily off time of 4.87 hr after 3 months (n = 37) to 6.25 hr after 9 years (n = 2). Diskynesias remained stables in 28 patients (75.7%) and improved in 5 patients (13.5%). There was no neuropsychological deterioration, but an improvement in attentional functions, voluntary motor control, and semantic fluency. Quality of sleep did not worsen, and there was an improvement in the subjective parameters, although overnight polysomnography did not change. There was a significant sustained improvement of 37% in PD-Q39 after 3 months and to 1 year, and a significant reduction in caregiver burden of 10% after 3 months.

CONCLUSION

LCIG infusion is a safe and efficacious treatment for the control of motor fluctuations, and for improvement or nonworsening of nonmotor aspects, long-term sustained, and feasible for use in routine care.

Potential of APDM mobility lab for the monitoring of the progression of Parkinson's disease

APDM's Mobility Lab system provides portable, validated, reliable, objective measures of balance and gait that are sensitive to Parkinson's disease (PD). In this review, we describe the potential of objective measures collected with the Mobility Lab system for tracking longitudinal progression of PD. Balance and gait are among the most important motor impairments influencing quality of life for people with PD. Mobility Lab uses body-worn, Opal sensors on the legs, trunk and arms during prescribed tasks, such as the instrumented Get Up and Go test or quiet stance, to quickly quantify the quality of balance and gait in the clinical environment. The same Opal sensors can be sent home with patients to continuously monitor the quality of their daily activities. Objective measures have the potential to monitor progression of mobility impairments in PD throughout its course to improve patient care and accelerate clinical trials.

Improvement of dyskinesias with L-dopa infusion in advanced Parkinson's disease

OBJECTIVES

We wanted to investigate whether continuous intrajejunal levodopa-carbidopa intestinal gel (LCIG) therapy has an antidyskinetic effect in patients with Parkinson's disease (PD) and troublesome dyskinesias. We also sought to examine the effect of LCIG therapy on motor function and health-related quality of life (HRQoL).

MATERIALS AND METHODS

This open-label pilot study used a single group pre-post design with follow-up at 6 months. Nine patients with PD who reported to spend at least 3 h per day in on with troublesome dyskinesia were included. The patients were examined at baseline using clinical and self-assessment measures and then switched from peroral/transdermal pharmacotherapy to LCIG therapy. Data collection was repeated 6 months after the pharmaceutical intervention. Nonparametric statistical methods were used for data analyses.

RESULTS

The mean time spent in on with troublesome dyskinesia per day after 6 months of LCIG therapy decreased by 47% (P < 0.05). This observation was paralleled by a 112% increase in mean time spent in on without troublesome dyskinesia (P < 0.01). Patient self-assessment of dyskinesia intensity on the visual analog scale displayed a 90% reduction of mean dyskinesia intensity (P < 0.01) and patients also exhibited less dyskinesia during standardized levodopa tests. Furthermore, we noted improvements in motor function and HRQoL.

CONCLUSIONS

In this pilot study, we found indications that LCIG therapy has a substantial antidyskinetic effect and could be an alternative also for PD patients with dyskinesias as a major symptom. However, further studies with blinded evaluation and larger numbers of patients are warranted to confirm the findings.

Clinical management of patients with advanced Parkinson's disease treated with continuous intestinal infusion of levodopa/carbidopa

Patients with Parkinson's disease often have a good initial response to dopaminergic therapy but later usually develop motor fluctuations and dyskinesia. In these patients, continuous infusion of levodopa-carbidopa intestinal gel (LCIG) allows for maintaining adequate dopamine levels and for improving motor and nonmotor symptoms, as well as quality of life and autonomy. Adequate candidate selection and follow-up are crucial for treatment success. Management should be multidisciplinary, and patient and caregiver education is a priority. This expert consensus document has been developed by a team of neurologists, gastroenterologists and nurses who have a vast experience in LCIG therapy, with an intention to provide knowledge and tools to facilitate patient management throughout all phases of LCIG treatment process.

[Current possibilities of quality of life improvement in the late stages of Parkinson's disease]

In this review, the authors describe the influence of Parkinson's disease on of the quality of life (QoL) of patients and highlight the importance of this parameter for assessment of treatment efficacy. Special attention is drawn to improvement of QoL in patients with resistant motor complications using invasive methods based on continuous dopaminergic stimulation. In the aspect of the influence on QoL, the main results of the studies of levodopa-carbidopa intestinal gel are reviewed.

Impact of Pharmacotherapy on Quality of Life in Patients with Parkinson's Disease

Quality of life (QoL) is a patient-reported outcome frequently included in Parkinson's disease (PD) clinical trials as a secondary or tertiary endpoint. However, QoL is an important variable that reflects the impact of disease and treatment from the patients' perspective. In a chronic, neurodegenerative disease such as PD, with a wide range of complex symptoms, QoL provides valuable and comprehensive information on the patients' health status. This narrative review aims to evaluate the effect of specific PD treatments currently in use on patients' QoL measured with the Parkinson's Disease Questionnaire, 39-item (PDQ-39) or 8-item (PDQ-8) version. A quantification of this effect is provided by calculation of the relative change and effect size. These two parameters allow an intuitive standardized approach to the importance of change based on its magnitude. Some high-quality studies (Level I) were found for levodopa (immediate- or extended-release formulations), levodopa with added-on catechol-O-methyltransferase (COMT) inhibitors, levodopa/carbidopa gel for intestinal infusion, some dopamine agonists (ropinirole, cabergoline, pergolide), and the monoamine oxidase B (MAO-B) inhibitor safinamide. As a whole, these studies found a beneficial effect of variable magnitude, weak to moderate, on patients' QoL. Studies with a lower level of evidence or not providing enough data to estimate relative change and effect size, including those for the apomorphine subcutaneous pump, also reported improvement of QoL, but the evidence was insufficient to confirm the effect. More high-quality studies focused on QoL are needed to determine the real impact of PD drug treatments for this important outcome.

Motor and non-motor symptoms of Parkinson's disease and their impact on quality of life and on different clinical subgroups

INTRODUCTION

The aim of the present study is to analyse the influence that motor and non-motor symptoms have on the quality of life (QoL) of patients with Parkinson's disease (PD), and to study the relationship between the two types of symptoms.

MATERIAL AND METHODS

This cross-sectional study included 103 patients with PD (55 men and 48 women). Quality of life was measured on the PDQ-39 scale. The UPDRS scale (I-IV) was also used, and different items were grouped to analyse the presence of tremor, rigidity, bradykinesia, and axial symptoms. The non-motor symptoms scale (NMSS) was administered to assess non-motor symptoms. We performed correlation analyses between different scales to analyse the influence of motor and non-motor symptoms on QoL.

RESULTS

Correlations were observed between the PDQ-39 summary index (PDQ39_SI) and the NMSS (correlation coefficient [cc], 0.56; p<.001), UPDRS III (cc, 0.44; p< .001) and UPDRS IV (cc, 0.37; p<.001) scores. The strongest correlation was between cognitive symptoms and mood. The analysis pointed to a direct relationship between the NMSS score and axial symptoms (cc, 0.384; p<.01), bradykinesia (cc, 0.299; p<.01), and to a lesser extent, rigidity (cc, 0.194; p<.05). No relationship was observed between presence of tremor and the NMSS score.

CONCLUSION

Cognitive symptoms and mood exert the most influence on QoL of patients with PD. We found at least two phenotypes; one with predominantly axial symptoms, with significant involvement of non-motor symptoms, and a tremor-associated phenotype in which these symptoms are less prevalent.

Emerging therapies for Parkinson's disease: from bench to bedside

The prevalence of Parkinson's disease (PD) increases with age and is projected to increase in parallel to the rising average age of the population. The disease can have significant health-related, social, and financial implications not only for the patient and the caregiver, but for the health care system as well. While the neuropathology of this neurodegenerative disorder is fairly well understood, its etiology remains a mystery, making it difficult to target therapy. The currently available drugs for treatment provide only symptomatic relief and do not control or prevent disease progression, and as a result patient compliance and satisfaction are low. Several emerging pharmacotherapies for PD are in different stages of clinical development. These therapies include adenosine A2A receptor antagonists, glutamate receptor antagonists, monoamine oxidase inhibitors, anti-apoptotic agents, and antioxidants such as coenzyme Q10, N-acetyl cysteine, and edaravone. Other emerging non-pharmacotherapies include viral vector gene therapy, microRNAs, transglutaminases, RTP801, stem cells and glial derived neurotrophic factor (GDNF). In addition, surgical procedures including deep brain stimulation, pallidotomy, thalamotomy and gamma knife surgery have emerged as alternative interventions for advanced PD patients who have completely utilized standard treatments and still suffer from persistent motor fluctuations. While several of these therapies hold much promise in delaying the onset of the disease and slowing its progression, more pharmacotherapies and surgical interventions need to be investigated in different stages of PD. It is hoped that these emerging therapies and surgical procedures will strengthen our clinical armamentarium for improved treatment of PD.

Motor and nonmotor complications in Parkinson's disease: an argument for continuous drug delivery?

The complications of long-term levodopa therapy for Parkinson’s disease (PD) include motor fluctuations, dyskinesias, and also nonmotor fluctuations—at least equally common, but less well appreciated—in autonomic, cognitive/psychiatric, and sensory symptoms. In seeking the pathophysiologic mechanisms, the leading hypothesis is that in the parkinsonian brain, intermittent, nonphysiological stimulation of striatal dopamine receptors destabilizes an already unstable system. Accordingly, a major goal of PD treatment in recent years has been the attainment of continuous dopaminergic stimulation (CDS)—or, less theoretically (and more clinically verifiable), continuous drug delivery (CDD). Improvements in the steadiness of the plasma profiles of various dopaminergic therapies may be a signal of progress. However, improvements in plasma profile do not necessarily translate into CDS, or even into CDD to the brain. Still, it is reassuring that clinical studies of approaches to CDD have generally been positive. Head-to-head comparative trials have often failed to uncover evidence favoring such approaches over an intermittent therapy. Nevertheless, the findings among recipients of subcutaneous apomorphine infusion or intrajejunal levodopa/carbidopa intestinal gel suggest that nonmotor PD symptoms or complications may improve in tandem with motor improvement. In vivo receptor binding studies may help to determine the degree of CDS that a dopaminergic therapy can confer. This may be a necessary first step toward establishing whether CDS is, in fact, an important determinant of clinical efficacy. Certainly, the complexities of optimal PD management, and the rationale for an underlying strategy such as CDS or CDD, have not yet been thoroughly elucidated.

Frequent administration of levodopa/carbidopa microtablets vs levodopa/carbidopa/entacapone in healthy volunteers

OBJECTIVES

An oral dispersible microtablet formulation of levodopa/carbidopa 5/1.25 mg (LC-5) was developed for individualized repeated dosing. The aim was to compare pharmacokinetic profiles of LC-5 and levodopa/carbidopa/entacapone (LCE).

MATERIALS AND METHODS

A randomized, crossover study was carried out in 11 healthy subjects. Plasma concentrations of levodopa, carbidopa and 3-O-methyldopa were determined after intake of 300 mg levodopa during the day, either as three intakes of 100/25/200 mg LCE or as a morning dose of 75/18.25 mg followed by five repeated doses of 45/11.25 mg LC-5.

RESULTS

Repeated dosing (2.4-hourly) with LC-5 microtablets compared to LCE (6-hourly) avoided long periods with low plasma levodopa levels. Time to maximum plasma concentrations was significantly shorter for LC-5. LC-5 showed lower fluctuation index (FI) in plasma compared to LCE (ANOVA P = 0.0028). FI for dose 2-5 was on average 1.26 for levodopa in LC-5, and 2.23 for dose 1-2 of LCE. The ratio between the two mean FI:s is 0.565; that is, LC-5 gave nearly half the FI as compared to LCE.

CONCLUSIONS

Fractionation of levodopa with LC-5 into small, frequent administrations as compared to standard administrations of LCE decreased the FI in plasma for both levodopa and carbidopa by nearly half.

Duodopa® treatment for advanced Parkinson's disease: a review of efficacy and safety

Enterally administered levodopa/carbidopa gel (Duodopa®) is used for the treatment of advanced Parkinson's disease (PD) in patients with motor fluctuations and dyskinesias. This review summarizes the current efficacy and safety data on this drug. Clinically important differences (CID) have been used to assess whether statistical improvements in symptoms translate into meaningful improvements for the patients. A PubMed search in February 2012 found 23 papers with efficacy data and 33 with safety data. Of 11 studies reporting Unified Parkinson's Disease Rating Scale (UPDRS) III scores, 10 found improvements that met the CID of 10.8 points. Of 7 studies reporting UPDRS IV scores, 5 found improvements meeting the CID of 2.3 points. Quality of life (QoL) was assessed in 6 studies using the 8- or 39-question version of the Parkinson's disease Questionnaire, and all reported improvements meeting the CID (10 points). Due to the nature of the data, it is not possible to give exact numbers for the frequency of adverse events. However, the findings seem to be in line with a previous report stating the majority of adverse events were related to the infusion system or surgical procedure rather than the drug. In conclusion, the large majority of studies have reported that Duodopa® is clinically effective in relieving the symptoms of advanced PD and improving QoL in comparison with conventional therapy. High-quality randomized trials with larger patient numbers will yield greater insights into the efficacy and safety of this treatment.

Pharmacoeconomic considerations of treating patients with advanced Parkinson's disease

INTRODUCTION

Parkinson's disease (PD) is one of the most common neurodegenerative diseases. In the later (advanced) stages of PD, the initial treatment of early PD becomes less effective and long-term side effects of dopaminergic treatment become apparent. In advanced PD, motor and non-motor complications occur, which increase treatment costs. Increasing disability and impaired activities of daily living concomitantly raise indirect costs, due to loss in productivity. Hence, the economic burden of advanced PD is substantial for both the society and the patients with their caregivers.

AREAS COVERED

A systematic literature search was performed involving the databases NHS CRD (National Health Service Centre for Reviews and Dissemination) and PubMed until July 15, 2011. "Parkinson" [Mesh] and "cost" were used as search terms in PubMed and only "Parkinson" in the CRD database.

EXPERT OPINION

Economic evaluations are scarce and heterogeneous, and their interpretation may be limited due to methodological shortcomings. Dopamine agonists, COMT and MAO-B inhibitors as well levodopa infusion and deep brain stimulation are reported to be cost-effective in the respective decision frameworks. However, these results are heavily dependent on assumptions of drug costs and effect sizes used in the models. More detailed real-life information from long-term clinical trials is needed to feed the economic models, especially for head-to-head comparisons. To date, no economic evaluation has been undertaken for possible neuroprotective/disease modifying effects, and further research is needed for evaluations of interventions for non-motor symptoms.

Long-term exposure to duodenal levodopa/carbidopa infusion therapy improves quality of life in relation especially to mobility, activities of daily living, and emotional well-being

BACKGROUND

Continuous duodenal levodopa infusion (DLI) is an effective therapy that improves quality of life (QoL) in advanced Parkinson's disease (PD). However, in which aspects improve the patients their QoL has been poorly documented.

METHODS

We evaluated 39-item Parkinson's disease Quality of Life Questionnaire Summary Index score (PDQ-39SI) changes analyzing its different domains in nine patients with advanced PD treated with DLI.

RESULTS

All the patients (64.7 ± 11.1 years, 55.5% men) improved PDQ-39SI 6 months after beginning with DLI (29.7 ± 8.6, P = 0.008) and after median duration infusion of 25.3 ± 8.8 months (34.8 ± 11.2, P = 0.008) compared with baseline (55.6 ± 11.5). All domains except social support improved significantly at 6 months. Mobility (P = 0.012), activities of daily living (P = 0.015), and emotional well-being (P = 0.008) improved significantly at the end of the follow-up.

CONCLUSIONS

DLI improves QoL in patients with advanced PD after short- and long-term exposure. Whereas all domains except social support improve after 6 months under DLI, only mobility, activities of daily living and emotional well-being improve significantly after long-term exposure to DLI.

Health-related quality of life as an outcome variable in Parkinson's disease

In the past three decades, health-related quality of life (HRQoL) has become an outcome variable in Parkinson's disease clinical trials. This review considers the measuring tools that have been developed, suitability of data reporting, complexity of outcome interpretation, and clinical application to provide evidence regarding available therapeutic interventions to date. In the introduction, different terms regarding quality of life are clearly defined. The methodology section offers an overview of generic, disease specific, and recommended HRQoL scales in Parkinson's disease and the most important psychometric attributes a scale should meet. The interpretation of HRQoL outcomes is complex and not intuitive. Thus, appropriate reporting of data is crucial in order to calculate relative change, a result that facilitates understanding to what extent an intervention is beneficial. The concept of minimally important change/difference is explained as well as the different approaches to its calculation (anchor-based and distribution-based methods). In the results section, a brief overview of the impact on HRQoL of currently available treatments in Parkinson's disease is provided. Special emphasis is given to data assessment, highlighting reports that helped understanding of the clinical significance of the intervention and therefore aided in making therapeutic decisions. The discussion section emphasizes the need for more clinical trials with HRQoL as a primary outcome and standardized reporting in order to further our understanding of the complexity of treatment effects and make evidence-based clinical decisions regarding HRQoL in patients with Parkinson's disease.

Validation of a home environment test battery for supporting assessments in advanced Parkinson's disease

Test sequences in a test battery for Parkinson's disease patients, consisting of self-assessments and motor tests, were carried out repeatedly in a telemedicine setting, during week-long test periods and results were summarized in an 'overall score'. 35 patients in stable and fluctuating conditions (15 age- and gender-matched pairs) used the test battery for 1 week, and were then assessed with UPDRS and PDQ-39. This procedure was repeated 1 week later, without treatment changes. Reliability was assessed by intraclass correlation coefficients and Cronbach's alpha. Convergent validity was assessed by Spearman rank correlations and known-groups' validity, by the Mann-Whitney test. According to anonymous usability questionnaires, the patients could easily complete the tasks. Median compliance (93%) and test-retest reliability (0.88) were good. The correlations between overall score and total UPDRS (-0.64) and PDQ-39 (-0.72) were adequate. Median overall score was 18% better in the stable compared to the fluctuating group (p = 0.0014).

A web application for follow-up of results from a mobile device test battery for Parkinson's disease patients

This paper describes a web-based system for enabling remote monitoring of patients with Parkinson's disease (PD) and supporting clinicians in treating their patients. The system consists of a patient node for subjective and objective data collection based on a handheld computer, a service node for data storage and processing, and a web application for data presentation. Using statistical and machine learning methods, time series of raw data are summarized into scores for conceptual symptom dimensions and an "overall test score" providing a comprehensive profile of patient's health during a test period of about one week. The handheld unit was used quarterly or biannually by 65 patients with advanced PD for up to four years at nine clinics in Sweden. The IBM Computer System Usability Questionnaire was administered to assess nurses' satisfaction with the web application. Results showed that a majority of the nurses were quite satisfied with the usability although a sizeable minority were not. Our findings support that this system can become an efficient tool to easily access relevant symptom information from the home environment of PD patients.

Levodopa-carbidopa intestinal gel for treatment of advanced Parkinson's disease

BACKGROUND

Levodopa is the mainstay of Parkinson's disease (PD) treatment, but is often eventually associated with disabling motor complications in patients with advanced PD. The inability of perorally administered levodopa to provide more physiologic continuous dopaminergic stimulation (CDS) is a leading hypothesis to explain these complications.

OBJECTIVE

To investigate the cumulative efficacy and safety, and re-evaluate the role, of levodopa-carbidopa intestinal gel (LCIG) infusion in treatment of advanced PD patients experiencing levodopa-associated motor complications, through its purported mechanism for providing CDS.

METHODS

Literature searches in the MEDLINE/PubMed database were used to identify peer-reviewed publications examining the role of CDS in levodopa-associated motor complications and pharmacologic strategies for CDS, focusing on LCIG infusion for advanced PD patients.

RESULTS

LCIG, an aqueous gel, is continuously infused (daytime only or 24 h) via a portable pump and tube permanently inserted into the duodenum through percutaneous endoscopic gastrostomy (PEG). LCIG infusion provides stable levodopa plasma levels, which are significantly less variable than those with oral levodopa. Clinical trials indicate LCIG may significantly improve motor complications (reduction of time in 'off' and time in 'on with dyskinesias'), motor scores using the Unified Parkinson's Disease Rating Scale (UPDRS), non-motor symptomatology (Non-motor Symptom Scale) and health-related quality of life (HRQOL) in advanced PD patients. The adverse-event profile of LCIG is similar to that of oral levodopa, although technical problems with the infusion device have occurred in up to 70% of patients.

CONCLUSION

LCIG has demonstrated efficacy in reducing levodopa-associated motor complications in patients with advanced PD, and improving UPDRS and HRQOL scores. Because it involves PEG and its associated risks, LCIG is recommended for patients in whom motor fluctuations and dyskinesias are inadequately treated with traditional peroral medication. For these patients, LCIG can be a valuable alternative to deep brain stimulation (DBS), especially when DBS is contraindicated. These conclusions are limited by the modest number and size of completed randomized, controlled trials of LCIG.

Activities of daily living and quality of life in persons with newly diagnosed Parkinson's disease according to subtype of disease, and in comparison to healthy controls

OBJECTIVE

To describe activity of daily living (ADL) and quality of life (QoL) at first visit to a neurological centre, in patients subsequently diagnosed with Parkinson's disease (PD), according to subtype of disease and compared to healthy controls.

MATERIALS AND METHODS

99 patients and 31 controls were included. Patients were classified into three groups according to predominant symptoms: 50 Postural instability-gait difficulties (PIGD), 37 tremor dominant, 12 indeterminate. Evaluations included ADL-taxonomy, SF-36, and the Parkinson disease questionnaire (PDQ-39).

RESULTS

Patients experienced early on limitations in ADL and QoL compared to controls. Patients with PIGD subtype had already at first visit a worse status, clinically and in ADL and QoL, than patients with tremor dominant type.

CONCLUSIONS

Already at first visit to a neurological centre, patients who will eventually receive the diagnosis of PD exhibited restrictions in ADL and QoL. Patients with axial symptoms were affected most.

From the cell to the clinic: a comparative review of the partial D₂/D₃receptor agonist and α2-adrenoceptor antagonist, piribedil, in the treatment of Parkinson's disease

Though L-3,4-dihydroxyphenylalanine (L-DOPA) is universally employed for alleviation of motor dysfunction in Parkinson's disease (PD), it is poorly-effective against co-morbid symptoms like cognitive impairment and depression. Further, it elicits dyskinesia, its pharmacokinetics are highly variable, and efficacy wanes upon long-term administration. Accordingly, "dopaminergic agonists" are increasingly employed both as adjuncts to L-DOPA and as monotherapy. While all recognize dopamine D(2) receptors, they display contrasting patterns of interaction with other classes of monoaminergic receptor. For example, pramipexole and ropinirole are high efficacy agonists at D(2) and D(3) receptors, while pergolide recognizes D(1), D(2) and D(3) receptors and a broad suite of serotonergic receptors. Interestingly, several antiparkinson drugs display modest efficacy at D(2) receptors. Of these, piribedil displays the unique cellular signature of: 1), signal-specific partial agonist actions at dopamine D(2)and D(3) receptors; 2), antagonist properties at α(2)-adrenoceptors and 3), minimal interaction with serotonergic receptors. Dopamine-deprived striatal D(2) receptors are supersensitive in PD, so partial agonism is sufficient for relief of motor dysfunction while limiting undesirable effects due to "over-dosage" of "normosensitive" D(2) receptors elsewhere. Further, α(2)-adrenoceptor antagonism reinforces adrenergic, dopaminergic and cholinergic transmission to favourably influence motor function, cognition, mood and the integrity of dopaminergic neurones. In reviewing the above issues, the present paper focuses on the distinctive cellular, preclinical and therapeutic profile of piribedil, comparisons to pramipexole, ropinirole and pergolide, and the core triad of symptoms that characterises PD-motor dysfunction, depressed mood and cognitive impairment. The article concludes by highlighting perspectives for clarifying the mechanisms of action of piribedil and other antiparkinson agents, and for optimizing their clinical exploitation.

The pathophysiological basis of sensory disturbances in Parkinson's disease

The diagnosis of Parkinson's disease (PD) is still based on the recognition of the cardinal motor features. However, it is now recognized that non-motor manifestations (NMM) may actually precede the emergence of motor manifestations. NMM are very frequently present in the overall population of PD patients and are a major determinant of their quality of life. In this article we discuss the origin of sensory manifestations in PD, particularly focus on pain mechanisms, which is the most frequent and better studied NMM. Analysis of experimental and clinical data reveals that the basal ganglia (BG) indeed have an anatomo-functional organization which sustains sensory functions. In addition, the dopaminergic system is also engaged in the modulation and integration of sensory information and the response to pain. In patients with PD, pain is often related with motor fluctuations and dyskinesias induced by dopaminergic treatments, which suggest some common mechanisms with the origin of motor complications in PD. Clinically, sensory manifestations are often disturbing and poorly treated and may occasionally become a major cause of disability for PD patients. Thus, more clinical and basic studies are warranted to clarify pain mechanisms in PD, with the aim of achieving better treatments.

Comparison of apomorphine and levodopa infusions in four patients with Parkinson's disease with symptom fluctuations

BACKGROUND

Motor fluctuations in patients with advanced Parkinson's disease may be successfully treated with subcutaneous apomorphine infusion or intraduodenal levodopa/carbidopa infusion. No comparative trials of these two alternatives were performed.

AIMS OF THE STUDY

We present a subanalysis from a randomized crossover clinical trial where levodopa infusion as monotherapy was compared with any other combination of pharmacotherapy in fluctuating patients. Four patients used apomorphine infusion and oral levodopa in the comparator arm. The results of these four patients are presented in detail.

METHODS

The duration of the trial was 3 + 3 weeks. Patients were video-recorded half-hourly on two non-consecutive days of both treatment arms. Blinded video ratings were used. Patient self-assessments of motor function and quality-of-life (QoL) parameters were captured using an electronic diary.

RESULTS

Ratings in moderate to severe "off" state ranged 0-44% on apomorphine infusion and 0-6% on levodopa infusion. Moderate to severe dyskinesias were not recorded in any of the treatments. QoL was reported to be improved in all patients on duodenal levodopa infusion.

CONCLUSIONS

Monotherapy with duodenal infusion of levodopa was more efficacious and brought greater QoL than combination therapy with apomorphine infusion in these fluctuating patients.

Short-term cost and health consequences of duodenal levodopa infusion in advanced Parkinson's disease in Sweden: an exploratory study

Levodopa is the cornerstone treatment for Parkinson's disease, but the short half-life of levodopa limits its usefulness in late stages of the disease. Duodenal levodopa infusion (DLI) allows more stable plasma levels and better motor symptom control. To explore the costs and health benefits of replacing conventional oral polypharmacy with DLI in patients with advanced Parkinson's disease, from a Swedish healthcare payer perspective. Based on a clinical, randomized, crossover study with 24 patients (DIREQT), a decision analytic model predicted 2-year drug costs and QALYs for conventional oral therapy and for DLI. Health-related quality of life (HR-QOL) was recorded using a 15-dimensional (15D) utility instrument at baseline and during the two 3-week trial periods, and then at eight follow-up visits during the subsequent 6 months. Use of medication was based on data from DIREQT and previous studies. Unit costs were based on market prices (drugs) and customary charges in Sweden. All costs were expressed in Swedish kronor (SEK), year 2004 values euro 1.00 approximately SEK9.17, $US1.00 = SEK7.47). Future costs and outcomes were discounted at 3%. One-way and probabilistic sensitivity analyses were conducted. The mean utility scores were 0.77 for DLI and 0.72 for conventional therapy (p = 0.02). A considerable variation in the scores was observed during the study. The expected per-patient 2-year cost of DLI was SEK562 000 while it was SEK172 000 for conventional therapy. The mean number of QALYs was 1.48 and 1.42, respectively, representing an incremental cost of SEK6.1 million per QALY for DLI (all values discounted at 3%). Using other assumptions in sensitivity analyses, the cost per QALY could be as low as SEK456 000. This analysis can be considered exploratory only; it is based on very limited data. Nevertheless, our findings suggest that DLI results in a significant improvement in HR-QOL. However, the cost per QALY is likely to be higher than customary cost-effectiveness thresholds. Whether these benefits justify the additional costs depends on how the health benefits are measured and how these benefits are valued by society.