Search

Contains fulltext : 287484.pdf (Publisher’s version ) (Open Access) BACKGROUND: Iron content is increased in the substantia nigra of persons with Parkinson's disease and may contribute to the pathophysiology of the disorder. Early research suggests that the iron chelator deferiprone can reduce nigrostriatal iron content in persons with Parkinson's disease, but its effects on disease progression are unclear. METHODS: We conducted a multicenter, phase 2, randomized, double-blind trial involving participants with newly diagnosed Parkinson's disease who had never received levodopa. Participants were assigned (in a 1:1 ratio) to receive oral deferiprone at a dose of 15 mg per kilogram of body weight twice daily or matched placebo for 36 weeks. Dopaminergic therapy was withheld unless deemed necessary for symptom control. The primary outcome was the change in the total score on the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 260, with higher scores indicating more severe impairment) at 36 weeks. Secondary and exploratory clinical outcomes at up to 40 weeks included measures of motor and nonmotor disability. Brain iron content measured with the use of magnetic resonance imaging was also an exploratory outcome. RESULTS: A total of 372 participants were enrolled; 186 were assigned to receive deferiprone and 186 to receive placebo. Progression of symptoms led to the initiation of dopaminergic therapy in 22.0% of the participants in the deferiprone group and 2.7% of those in the placebo group. The mean MDS-UPDRS total score at baseline was 34.3 in the deferiprone group and 33.2 in the placebo group and increased (worsened) by 15.6 points and 6.3 points, respectively (difference, 9.3 points; 95% confidence interval, 6.3 to 12.2; P

Background Sleep disturbances are common in Parkinson’s Disease (PD), with nocturnal akinesia being one of the most burdensome. Levodopa is frequently used in clinical routine to improve nocturnal akinesia, although evidence is not well proven. Methods We assessed associations of Levodopa intake with quality of sleep and perception of nocturnal akinesia in three PD cohorts, using the Parkinson’s Disease Sleep Scale (PDSS-2) in two cohorts and a question on nocturnal immobility in one cohort. In one cohort also objective assessment of mobility during sleep was performed, using mobile health technology. Results In an independent analysis of all three cohorts (in total n = 1124 PD patients), patients taking Levodopa CR reported a significantly higher burden by nocturnal akinesia than patients without Levodopa. Higher Levodopa intake and MDS-UPDRS part IV scores (indicating motor fluctuations) predicted worse PDSS-2 and higher subjective nocturnal immobility scores, while disease duration and severity were not predictive. Levodopa intake was not associated with objectively changed mobility during sleep. Conclusion Our results showed an association of higher Levodopa intake with perception of worse quality of sleep and nocturnal immobility in PD, indicating that Levodopa alone might not be suitable to improve subjective feeling of nocturnal akinesia in PD. In contrast, Levodopa intake was not relevantly associated with objectively measured mobility during sleep. PD patients with motor fluctuations may be particularly affected by subjective perception of nocturnal mobility. This study should motivate further pathophysiological and clinical investigations on the cause of perception of immobility during sleep in PD.

Aggregated α-synuclein plays an important role in the pathogenesis of Parkinson's disease. The monoclonal antibody prasinezumab, directed at aggregated α-synuclein, is being studied for its effect on Parkinson's disease.In this phase 2 trial, we randomly assigned participants with early-stage Parkinson's disease in a 1:1:1 ratio to receive intravenous placebo or prasinezumab at a dose of 1500 mg or 4500 mg every 4 weeks for 52 weeks. The primary end point was the change from baseline to week 52 in the sum of scores on parts I, II, and III of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 236, with higher scores indicating greater impairment). Secondary end points included the dopamine transporter levels in the putamen of the hemisphere ipsilateral to the clinically more affected side of the body, as measured by 123I-ioflupane single-photon-emission computed tomography (SPECT).A total of 316 participants were enrolled; 105 were assigned to receive placebo, 105 to receive 1500 mg of prasinezumab, and 106 to receive 4500 mg of prasinezumab. The baseline mean MDS-UPDRS scores were 32.0 in the placebo group, 31.5 in the 1500-mg group, and 30.8 in the 4500-mg group, and mean (±SE) changes from baseline to 52 weeks were 9.4±1.2 in the placebo group, 7.4±1.2 in the 1500-mg group (difference vs. placebo, -2.0; 80% confidence interval [CI], -4.2 to 0.2; P = 0.24), and 8.8±1.2 in the 4500-mg group (difference vs. placebo, -0.6; 80% CI, -2.8 to 1.6; P = 0.72). There was no substantial difference between the active-treatment groups and the placebo group in dopamine transporter levels on SPECT. The results for most clinical secondary end points were similar in the active-treatment groups and the placebo group. Serious adverse events occurred in 6.7% of the participants in the 1500-mg group and in 7.5% of those in the 4500-mg group; infusion reactions occurred in 19.0% and 34.0%, respectively.Prasinezumab therapy had no meaningful effect on global or imaging measures of Parkinson's disease progression as compared with placebo and was associated with infusion reactions. (Funded by F. Hoffmann-La Roche and Prothena Biosciences; PASADENA ClinicalTrials.gov number, NCT03100149.).

Polypharmacy is common practice in Parkinson's disease. Medical treatment targeting the dopaminergic system alone may include up to five different compounds: L-DOPA (in combination with a DOPA decarboxylase inhibitor), a catechol-O-methyltransferase (COMT) and a monoamine oxidase (MAO-B) inhibitor and a dopamine agonist. Particular motor and non-motor symptoms may require additional specific therapeutics, such as drugs aimed at tremor control and to treat depression, dementia and orthostatic and autonomic dysfunction. No prospective studies have yet been performed with regard to the efficacy or the long-term benefit of combining such different treatments in Parkinson's disease and retrospective analyses are sparse. We thus tried to compile the available evidence for polypharmacy strategies in Parkinson's disease and devised an expert opinion statement.

Objective The pedunculopontine nucleus (PPN) has been proposed as a new deep brain stimulation (DBS) target for the treatment in idiopathic Parkinson’s syndrome (IPS) and progressive supranuclear palsy (PSP). In IPS, levodopa has been shown to induce alpha activity in the PPN, indicating a possible physiological role for these oscillations in movement control. Despite shared clinical features, the PPN is more severely affected in PSP than IPS. Here we investigated neuronal oscillations in the PPN in PSP and the influence of levodopa and movement. Methods Local field potentials were recorded bilaterally from the PPN of 4 PSP patients at rest, with levodopa and during self-paced leg movements. Results During rest, levodopa administration was associated with significantly increased alpha and reduced gamma activity in the PPN. Without levodopa, continuous movements were associated with reduced alpha and beta power. These differences between oscillatory power during movement and resting state were not observed with levodopa administration. Conclusion In PSP the changes in neuronal oscillations in the PPN region on levodopa administration are similar to those reported in IPS. The enhancement of lower frequency oscillations in the PPN is possibly influenced by a dopaminergic activation of the striatal pathway and a reduced pallidal inhibition. Significance Levodopa influences neuronal oscillations at low and high frequencies in the PPN region in Parkinsonian disorders.

Parkinson's disease is a chronic neurodegenerative movement disorder affecting people mainly beyond their 50s. Geriatric patients with Parkinson's disease experience a specific profile of comorbidities. Multimorbidity and resulting polypharmacotherapy are frequent at this age. Comorbid diseases, widely spread, involve arterial hypertension, ischemic heart disease, heart failure, atrial fibrillation, polyneuropathy, diabetes mellitus, cerebrovascular disease, sarcopenia, and frailty. Following years of drug development, levodopa is still the most effective drug for the treatment of motor symptoms. However, a wide range of other drugs are available with specific effects, contraindications, and complications. The treatment of geriatric patients with Parkinson's disease is challenging and requires the cooperation of multidisciplinary teams. A careful assessment of a patient's Parkinson's disease symptoms, comorbidities, medication, vital signs, and resources is crucial for an effective and safe therapy. Laboratory tests can assist in the identification of contraindications for specific treatments. Identifying potentially inadequate drugs from prescription lists can lead to a better targeted treatment for geriatric patients with Parkinson's disease. Future research should help develop a more evidence-based therapy of geriatric patients with Parkinson's disease. For this purpose, randomized controlled trials of geriatric patients are urgently needed. An international register concerning issues of safer drug application and monitoring could help to implement a better treatment.

Background In Germany, epidemiological information on Parkinson's disease (PD) is rare and outdated. Considering aging populations, current prevalences and incidence rates about this age-related disease would be important for adequate public health planning. Methods We used newly available health claims data sets from the largest German health insurer dating 2004-2007 and 2007-2010 with an analysis population in the base years of 491 038 persons aged 50 and older. Quarter-specific information about ICD-10 diagnoses and PD drug prescriptions from the inpatient and outpatient sectors was used to validate PD cases. Estimations were presented for two validation strategies relying on repeated PD diagnoses (SIa) and on one PD diagnosis followed by at least one PD drug prescription (SIb). Results The standardized prevalence was 797 (SIb) to 961/100 000 persons (SIa), showing an age-specific increase up to category 85-89 and a decline thereafter. The standardized incidence rate was 192 to 229/100 000 person-years with a similar age-specific shape. Prevalences and incidences rates were higher for men compared to women in regard to age. Conclusions Health claims data are found to be suitable for PD assessment using the repeated diagnoses or PD drug prescriptions as necessary criteria.

Background: Non-motor symptoms (NMS) are common in late stage Parkinson's disease (PD), as the frequency and severity of most of these symptoms increase with advancing disease. Objective: To assess effect of dopaminergic therapy on NMS in late stage PD and to investigate relationships between dopaminergic effect on NMS and on motor function. Method: Thirty PD patients in Hoehn and Yahr (HY) stages IV and V in "on" were included. Dopaminergic effect on non-motor symptomatology was assessed by the modified version of the Non-Motor Symptoms Scale (NMSS) in the "off" and the "on" state during a standardized L-dopa test, in parallel also assessing motor function. Results: NMS were common and many of the symptoms occurred in>80% of the individuals. The highest NMSS scores were seen within the NMSS domains 3: mood/apathy and 7: urinary in both the "off" and the "on" state. There was a statistically significant (p

Atypical Parkinson syndromes are a heterogeneous group of neurodegenerative diseases which present with parkinsonism and other non-motor symptoms. On the basis of the underlying pathology, namely the abnormal aggregation of the proteins alpha-synuclein or tau, atypical Parkinson syndromes can be divided into synucleinopathies (multiple system atrophy, Lewy body dementia) and tauopathies (progressive supranuclear palsy, corticobasal degeneration). Currently there are no effective treatments to slow down disease progression available. Medications which help to manage the symptoms show only temporary and insufficient efficacy. In recent years, preclinical research identified essential steps in the pathogenesis of the diseases. Treatments which inhibit pathological protein aggregation and its spreading were developed and showed promising results in animal models. First clinical trials of causal treatments targeting the underlying pathomechanism have been finished; several trials are recruiting patients or being planned at the moment. In the following article we present the latest developments regarding the causal therapy of atypical Parkinson syndromes and the current clinical trials.Bei den atypischen Parkinson Syndromen handelt es sich um eine Gruppe neurodegenerativer Erkrankungen, die klinisch durch eine akinetisch-rigide Symptomatik mit zusätzlichen nicht-motorischen Symptomen gekennzeichnet sind. Anhand ihrer Pathologie, dem zugrundeliegenden fehlgefalteten Protein, lassen sich diese in Synucleinopathien (Multisystematrophie und Demenz vom Lewy-Body-Typ) und Tauopathien (progressive supranukleäre Blickparese und Kortikobasale Degeneration) einteilen. Dabei existieren bisher keine kausalen Therapiemöglichkeiten, in den meist rasch progredienten Krankheitsverlauf einzugreifen. Symptomatische Therapien besitzen nur einen kurzfristigen, häufig unbefriedigenden Effekt. In den letzten Jahren konnten durch präklinische Forschung Pathomechanismen in der Krankheitsentstehung charakterisiert werden. Dabei wurden Substanzen entwickelt, die beispielsweise die pathologische Protein-Aggregation oder in die Verbreitung der Pathologie verhindern und im Tiermodell einen Einfluss auf das Fortschreiten der Krankheit zeigen konnten. Dabei wurden erste klinische Studien, welche in die Entstehung der zugrundeliegenden Pathologie eingreifen, durchgeführt; viele befinden sich aktuell in der Rekrutierung oder Planung. In folgendem Artikel stellen wir die aktuellen Entwicklungen im Gebiet der atypischen Parkinson Syndrome vor und präsentieren die aktuellen Studien.

OBJECTIVE: To delineate the natural history, diagnosis, and treatment response of Parkinson disease (PD) in individuals with 22q11.2 deletion syndrome (22q11.2DS), and to determine if these patients differ from those with idiopathic PD. METHODS: In this international observational study, we characterized the clinical and neuroimaging features of 45 individuals with 22q11.2DS and PD (mean follow-up 7.5 ± 4.1 years). RESULTS: 22q11.2DS PD had a typical male excess (32 male, 71.1%), presentation and progression of hallmark motor symptoms, reduced striatal dopamine transporter binding with molecular imaging, and initial positive response to levodopa (93.3%). Mean age at motor symptom onset was relatively young (39.5 ± 8.5 years); 71.4% of cases had early-onset PD (

Patients with Parkinson's disease show a wide heterogeneity of symptoms and comorbidities, requiring individualized therapeutic strategies, particularly in advanced stages of the disease. This is reflected by the choice of different substance classes and drugs for the treatment of end-of-dose fluctuations. Each of these drugs offers a characteristic profile of effects and unwanted side-effects, which has to be taken into consideration. Replacement of a substance by an alternative drug under consideration, for instance, of healthcare economics is possible only to a limited extent, since therapeutic effects as well as tolerability in the individual patient must be taken into account.Patienten mit einem idiopathischen Parkinsonsyndrom (IPS) weisen eine große Heterogenität an Symptomen und Komorbiditäten auf, die vor allem im fortgeschrittenen Stadium der Erkrankung eine individualisierte Therapiestrategie erfordern. Dies spiegelt sich auch in der Auswahl verschiedener Substanzklassen und Einzelwirkstoffe in der Therapie von End-of-Dose-Fluktuationen wider. Jede der verfügbaren Substanzen hat ein charakteristisches Wirkungs- und Nebenwirkungsprofil, welches bei der Anwendung berücksichtigt werden muss. Daher ist ein Austausch verschiedener Substanzen, auch unter medizin-ökonomischen Aspekten, nur bedingt möglich und erfordert sowohl die Berücksichtigung des therapeutischen Effektes als auch der Verträglichkeit beim einzelnen Patienten.

The effects of rasagiline on olfaction in animal studies are convincing. However, apart from various anecdotal patient reports, they could not be reproduced in prospective studies in humans. Cross-sectional data of large patient groups are still missing. The aim of this study was therefore to determine the olfactory function in a broad heterogeneous Parkinson's disease (PD) population with and without rasagiline intake. In this single-center, cross-sectional study 224 PD patients with and without rasagiline (1 mg/day) participated. Seventy-four of them received rasagiline as mono, or adjunct therapy. One-hundred fifty patients were untreated or received PD medication other than rasagiline. Comprehensive olfactory testing was performed for phenyl-ethyl alcohol odor thresholds, odor discrimination, and odor identification. Olfactory function did not differ between the two treatment groups with disease duration up to 29 years. Rasagiline-treated patients with disease duration of less than 8 years, however, presented with significant better odor discrimination abilities compared to PD patients without rasagiline treatment. This effect was no longer evident in patients with longer disease duration and proofed to be independent of age, sex, and medication. Our results may suggest that rasagiline treatment has a positive effect on the processing of olfactory information in early PD.

Dynamic modulations of large-scale network activity and synchronization are inherent to a broad spectrum of cognitive processes and are disturbed in neuropsychiatric conditions including Parkinson's disease. Here, we set out to address the motor network activity and synchronization in Parkinson's disease and its modulation with subthalamic stimulation. To this end, 20 patients with idiopathic Parkinson's disease with subthalamic nucleus stimulation were analysed on externally cued right hand finger movements with 1.5-s interstimulus interval. Simultaneous recordings were obtained from electromyography on antagonistic muscles (right flexor digitorum and extensor digitorum) together with 64-channel electroencephalography. Time-frequency event-related spectral perturbations were assessed to determine cortical and muscular activity. Next, cross-spectra in the time-frequency domain were analysed to explore the cortico-cortical synchronization. The time-frequency modulations enabled us to select a time-frequency range relevant for motor processing. On these time-frequency windows, we developed an extension of the phase synchronization index to quantify the global cortico-cortical synchronization and to obtain topographic differentiations of distinct electrode sites with respect to their contributions to the global phase synchronization index. The spectral measures were used to predict clinical and reaction time outcome using regression analysis. We found that movement-related desynchronization of cortical activity in the upper alpha and beta range was significantly facilitated with 'stimulation on' compared to 'stimulation off' on electrodes over the bilateral parietal, sensorimotor, premotor, supplementary-motor, and prefrontal areas, including the bilateral inferior prefrontal areas. These spectral modulations enabled us to predict both clinical and reaction time improvement from subthalamic stimulation. With 'stimulation on', interhemispheric cortico-cortical coherence in the beta band was significantly attenuated over the bilateral sensorimotor areas. Similarly, the global cortico-cortical phase synchronization was attenuated, and the topographic differentiation revealed stronger desynchronization over the (ipsilateral) right-hemispheric prefrontal, premotor and sensorimotor areas compared to 'stimulation off'. We further demonstrated that the cortico-cortical phase synchronization was largely dominated by genuine neuronal coupling. The clinical improvement with 'stimulation on' compared to 'stimulation off' could be predicted from this cortical decoupling with multiple regressions, and the reduction of synchronization over the right prefrontal area showed a linear univariate correlation with clinical improvement. Our study demonstrates wide-spread activity and synchronization modulations of the cortical motor network, and highlights subthalamic stimulation as a network-modulating therapy. Accordingly, subthalamic stimulation may release bilateral cortical computational resources by facilitating movement-related desynchronization. Moreover, the subthalamic nucleus is critical to balance inhibitory and facilitatory cortical players within the motor program.

This overview focuses on the aspects of the pharmacotherapy of Parkinson's disease, which is one of the most common disorders of the nervous system. This article presents the complexity of the pharmacotherapy of geriatric patients with neurological diseases.Information about the potential risk factors and aspects of drug safety in the pharmacotherapy of Parkinson's disease.Selective literature search using PubMed and the scientific-clinical experience of the authors.Patients with Parkinson's disease are usually geriatric patients with concomitant diseases. As a result they are often treated with comedication which leads to a complex medication regime with more than five drugs. Such polypharmacy increases the risk of adverse drug events due to the rising number of possible interactions and contraindications. To control this risk and maintain a safe therapy, certain measures should be considered. This implies additional need for educational work in order to create awareness regarding potential adverse drug events. In certain cases of diagnosed comorbidities or relevant drug prescriptions in the medication regime, follow-up examinations should be conducted.Specific parameters of Parkinson's disease, the health-related quality of life of affected patients and the quality of pharmacotherapeutic drug safety can be improved by targeted monitoring of the medication regime. As a result, the overall drug safety can be increased.

Urinary dysfunction (UD) is a common non-motor feature of Parkinson's disease (PD), and might be secondary to neurodegeneration involving cortical and subcortical brain areas. The possible link between UD and cognitive deficits has never been examined in frontal cortex impairment, and is still not completely understood in PD. In the present study, 94 PD patients underwent a comprehensive motor, cognitive and non-motor assessment. It was shown that 55.3% of patients reported UD, of which 17% needed specific urological treatment. Patients who reported UD performed worse on global cognition (PANDA, p = .05), visuo-constructive functions (CERAD/praxis, p = .03; and Figure Test, p = .03), and instrumental activities of daily living functions (IADL, p = .03), than patients without UD. The group with UD medication performed worse on global cognition (PANDA, p = .02) and visuo-constructive functions (CERAD/praxis, p = .05; CERAD/praxis recall, p = .05) than the UD group without medication, independent of anticholinergic treatment effect. Our findings suggest an association between cognitive impairment and UD in PD independent from symptomatic treatment.

Parkinson's disease is the second most common neurodegenerative illness after Alzheimer's disease. In its advanced stages, it is characterized by various special symptoms. In addition to non-motor signs, motor complications are most prominent and most often can only be inadequately improved with pulsatile oral therapies. However, with the aid of continuous dopaminergic stimulation, improvements can be achieved even in advanced stages of the disease. This will not only alleviate motor and non-motor symptoms, but will also lead to a better quality of life. In this context, continuous subcutaneous apomorphine administration by means of a pump has been well established. Its benefits, indications, limitations and practical implementation will be thoroughly described in the expert recommendation. Particularly noteworthy is the rather broad therapeutic window of apomorphine pump treatment, which can be optimally utilized by simple drug titration in a rapidly reversible process. This article presents the results of an expert meeting on apomorphine therapy which took place on July 6, 2016, in Frankfurt (M), Germany.Das idiopathische Parkinson-Syndrom ist nach der Alzheimer Erkrankung die zweithäufigste neurodegenerative Erkrankung und im fortgeschrittenen Stadium durch zahlreiche Besonderheiten gekennzeichnet. Neben nicht-motorischen Symptomen stehen oft motorische Komplikationen im Vordergrund, die mit pulsatilen oralen Therapien nur unzureichend verbessert werden können. Mithilfe der kontinuierlichen dopaminergen Stimulation lassen sich jedoch auch im fortgeschrittenen Stadium Optimierungen vornehmen, die neben der Verbesserung motorischer und nicht-motorischer Symptome auch eine höhere Lebensqualität erzielen können. Etabliert hat sich in diesem Zusammenhang die kontinuierliche subkutane Gabe von Apomorphin mittels Medikamentenpumpe, deren Nutzen, Indikationen, Anwendungsbeschränkungen und praktische Umsetzung in dieser Expertenempfehlung ausführlich dargestellt werden. Besonders hervorzuheben ist das vorteilhafte therapeutische Fenster der Apomorphin-Pumpentherapie, das durch einfache medikamentöse Titration bei einem schnell reversiblen Verfahren optimal ausgenutzt werden kann. Im vorliegenden Artikel werden die Ergebnisse eines Experten-Meetings zur Apomorphin-Therapie vorgestellt, das am 6. Juli 2016 in Frankfurt am Main stattgefunden hat.

Knowledge of patients' treatment needs is an important requirement for comprehensive long-term patient care. The objective of this investigation was to assess the requirements of patients with Parkinson's disease (PD) regarding pharmacotherapy.A total of 17,500 members of the German Parkinson Association were given the opportunity to anonymously answer a questionnaire about their health-related quality of life, PD pharmacotherapy and their improvement suggestions for new PD medication.Answers from 6351 patients were available for analysis. The majority (87.2%) of patients were older than 60 years; 88.9% had been diagnosed with PD for longer than 3 years and 84.4% selected one of the three most severe categories (categories 1-3 on a 6-point scale) when rating the impact of PD on their quality of life. Symptoms that were regarded as very important for improvement with pharmacotherapy included motor fluctuations (66.3%), early morning akinesia (55.4%) and sleep disturbances (43.5%). Properties of a new PD medication that were rated as very important included continuous drug delivery over 24 hours (66.6%) and 24-hour symptom control (55.8%). The majority of patients used physicians (84.2%) and/or self-help groups (69.4%) to obtain information about PD. Topics of particular interest included comorbid diseases (78.3%), mobility and exercise (77.3%) and research (53%).PD has a major impact on patients' quality of life. From the patient's perspective, PD pharmacotherapy needs to address a range of symptoms including not only motor symptoms, but also non-motor symptoms such as sleep disturbances. In selecting the most appropriate treatment regimen, patient preference is an important consideration.

Psychosis in Parkinson's disease (PD) is a frequent condition affecting >20 % of all PD patients. It is characterized by vivid dreams, nightmares, illusions, delusions and mostly visual hallucinations. Typically psychosis occurs in the late stage of PD, affecting up to 70 % of the patients following a disease duration of 20 years or more, and can severely interfere with the care of the patients, especially if the patients develop delusions. Psychosis is the principal cause of admission to a nursing home for PD patients. Hence, preemptive identification of risk factors, and avoidance and elimination of triggers are most important measures against psychosis in PD patients. Secondarily, pharmaceutical measures are being undertaken successively, including simplification of medication regimes, discontinuation of non-essential CNS-active drugs, ordered reduction of antiparkinsonian drugs, addition of cholesterinase inhibitors in cognitively impaired patients, and finally addition of antipsychotic medication with limited parkinsonian side effects. As psychosis in PD is a frequent and important problem, we set out to write a state-of-the-art guideline for its identification and treatment.

Although Levodopa-induced dyskinesias (LID) are one of the most compromising complications of dopaminergic treatment in Parkinson’s disease (PD), there is no widely accepted assessment tool available that evaluates LID quantitatively. This is of relevance as objective assessment may help to facilitate proof-of-concept studies with novel treatments and thus eventually contribute to better patient care. PD patients were asked to perform a grip-lift task as well as tapping tasks assessed with the “Q-Motor” system. PD patients were separated into three groups according to their modified abnormal involuntary movement scale (M-AIMS)–score: PD patients without dyskinesias (PDLID− n = 17), with slight dyskinesias (PDLID+ n = 15) and with severe dyskinesias (PDLID++ n = 15). An explorative analysis to identify measures detecting LID was performed with 5 PDLID− and 5 PDLID++ patients; these measures were then used in the remaining patients to assess the accuracy of the system to differentiate LID. The measures “Orientation-Index” and “Position-Index” of the grip-lift task differed significantly between the explorative cohorts. Using these two parameters for the differentiation of the remaining cohorts, the area under the ROC curve (AUC) yielded 0.809 for the differentiation of PDLID- vs. PDLID++, 0.852 for the differentiation of PDLID− vs. PDLID+ patients, and 0.830 for the differentiation of PDLID+ and PDLID++. The “Orientation-Index” and “Position-Index” of the Q-Motor assessment are sensitive, easy to apply and non-invasive measures for the objective assessment of manifestation and severity of LID.

l-Dopa-induced dyskinesias (LID) are the most common adverse effects of long-term dopaminergic therapy in Parkinson’s disease (PD). However, the exact mechanisms underlying dyskinesia are still unclear. For a long time, nigrostriatal degeneration and pulsatile stimulation of striatal postsynaptic receptors have been highlighted as the key factors for the development of LID. In recent years, PD models have revealed a wide range of non-dopaminergic neurotransmitter systems involved in pre- and postsynaptic changes and thereby contributing to the pathophysiology of LID. In the current review, we focus on therapeutic LID targets, mainly based on agents acting on dopaminergic, glutamatergic, serotoninergic, adrenergic, and cholinergic systems. Despite a large number of clinical trials, currently only amantadine and, to a lesser extent, clozapine are being used as effective strategies in the treatment of LID in clinical settings. Thus, in the second part of the article, we review the placebo-controlled trials on LID treatment in order to disentangle the changing scenario of drug development. Promising results include the extension of l-dopa action without inducing LID of the novel monoamine oxidase B- and glutamate-release inhibitor safinamide; however, this had no obvious effect on existing LID. Others, like the metabotropic glutamate-receptor antagonist AFQ056, showed promising results in some of the studies; however, confirmation is still lacking. Thus, to date, strategies of continuous dopaminergic stimulation seem the most promising to prevent or ameliorate LID. The success of future therapeutic strategies once moderate to severe LID occur will depend on the translation from preclinical experimental models into clinical practice in a bidirectional process.

Previous models proposed that the subthalamic nucleus (STN) is critical in the early phase of skill acquisition. We hypothesized that subthalamic deep brain stimulation modulates the learning curve in early classification learning. Thirteen idiopathic Parkinson's disease patients (iPD) with subthalamic deep brain stimulation (STN-DBS), 9 medically treated iPD, and 21 age-matched healthy controls were tested with a probabilistic classification task. STN-DBS patients were tested with stimulation OFF and ON, and medically treated patients with medication OFF and ON, respectively. Performance and reaction time were analyzed on the first 100 consecutive trials as early learning phase. Moreover, data were separated for low and high-probability patterns, and more differentiated strategy analyses were used. The major finding was a significant modulation of the learning curve in DBS patients with stimulation ON: although overall learning was similar to healthy controls, only the stimulation ON group showed a transient significant performance dip from trials '41-60' that rapidly recovered. Further analysis indicated that this might be paralleled by a modulation of the learning strategy, particularly on the high-probability patterns. The reaction time was unchanged during the dip. Our study supports that the STN serves as a relay in early classification learning and directs attention toward unacquainted content. The STN might play a role in balancing the short-term success against strategy optimization for improved long-term outcome.

Objective: To evaluate the effects of levodopa and the dopamine D2 agonist cabergoline on striatal dopamine turnover estimated as the inverse of the effective dopamine distribution volume ratio (EDVR) measured by 18 F-dopa PET in de novo Parkinson disease (PD). Methods: Single-center, parallel-group, randomized, observer-blinded study of cabergoline (3 mg/day) and levodopa (300 mg/day) over 12 weeks in patients with de novo PD. Primary efficacy measure was the change of the side-to-side averaged putaminal EDVR comparing baseline and end-of-maintenance period. Results: Thirty-five out of 39 randomized patients were assigned to the primary efficacy analysis (cabergoline, n = 17; levodopa, n = 18). At the end of treatment period, mean EDVRs were significantly lower compared to baseline solely in the levodopa group (relative change −1.0 ± 13.0% in cabergoline [ p = 0.525 when compared to baseline], −8.3 ± 11.8% in levodopa group [ p = 0.006]) with a nonsignificant trend between groups (mean relative difference: 7.3% (95% confidence interval −1.2% to 15.8%; p = 0.091). There was significant clinical improvement in both groups at 12 weeks compared to baseline, but no significant differences between groups in clinical and PET secondary outcome measures. Both pharmacologic treatments and PET scanning were well-tolerated and safe. Conclusion: Putaminal dopamine turnover is increased by levodopa treatment in de novo PD. The nonsignificant trend toward a larger influence by levodopa compared to cabergoline is supported by ancillary statistical analyses. This augmentation of early compensatory events by levodopa might contribute not only to its symptomatic effects, but also to its induction of motor complications.

Approximately 10,000-15,000 Parkinson's disease (PD) patients per year undergo surgery in Germany. The demographic developments along with further surgical progress and procedural refinements will lead to increasing numbers of PD patients in the operating theatre (OR). There are several perioperative risk factors for PD patients, they more often require prolonged intensive care treatment and warrant particular anesthesiological attention with regard to the choice of drugs and equipment. Careful evaluation of concomitant diseases, maintenance of oral Parkinson therapeutic drugs up to the time of surgery and continuous perioperative dopaminergic therapy are key factors for reducing postoperative morbidity in PD patients undergoing surgery.