The impact of rotigotine on cardiovascular autonomic function in early Parkinson's disease

A preclinical secondary pharmacology resource illuminates target-adverse drug reaction associations of marketed drugs

In vitro secondary pharmacology assays are an important tool for predicting clinical adverse drug reactions (ADRs) of investigational drugs. We created the Secondary Pharmacology Database (SPD) by testing 1958 drugs using 200 assays to validate target-ADR associations. Compared to public and subscription resources, 95% of all and 36% of active (AC50 < 1 µM) results are unique to SPD, with bias towards higher activity in public resources. Annotating drugs with free maximal plasma concentrations, we find 684 physiologically relevant unpublished off-target activities. Furthermore, 64% of putative ADRs linked to target activity in key literature reviews are not statistically significant in SPD. Systematic analysis of all target-ADR pairs identifies several putative associations supported by publications. Finally, candidate mechanisms for known ADRs are proposed based on SPD off-target activities. Here we present a freely-available resource for benchmarking ADR predictions, explaining phenotypic activity and investigating clinical properties of marketed drugs.

Safety considerations when using non-ergot dopamine agonists to treat Parkinson's disease

INTRODUCTION

Nonergot dopamine agonists (NEDA) represent an excellent treatment option for Parkinson's disease (PD) patients, in both early and advanced stages of the disease. The post-marketing phase of NEDA has highlighted, though, the occurrence of important long-term adverse events.

AREAS COVERED

This review reports recent updates on NEDA adverse events, analyzing neurobiological bases and risk factors of these complications. A literature search has been performed using Medline and reviewing the bibliographies of selected articles.

EXPERT OPINION

NEDA represents a very important option in the treatment of PD. Criticisms on their use can be overcome through a better knowledge of these molecules and of the risk factors for adverse events which allow specialists to prevent the occurrence of undesired complications and consent a tailor-based approach. Abbreviations: PD: Parkinson's disease, DA: dopamine agonists, NEDA: non-ergot dopamine agonists, ICD: impulse control disorders, DAWS: dopamine agonist withdrawal syndrome, CYP: Cytochrome P, PK: pharmacokinetic, AUC: area under the curve, HRT: hormone replacement therapy, AV: atrioventricular, HF: heart failure, OH: orthostatic hypotension, RBD: REM behavior disorders, PDP: Parkinson's disease psychosis, DRT: dopamine replacement therapy, DDS: dopamine dysregulation syndrome, MMSE: Mini-Mental state examination, EDS: excessive daytime somnolence.

High Cervical Spinal Cord Stimulation: A One Year Follow-Up Study on Motor and Non-Motor Functions in Parkinson's Disease

Background: The present study investigated the effectiveness of stimulation applied at cervical levels on pain and Parkinson’s disease (PD) symptoms using either tonic or burst stimulation mode. Methods: Tonic high cervical spinal cord stimulation (T-HCSCS) was applied on six PD patients suffering from low back pain and failed back surgery syndrome, while burst HCSCS (B-HCSCS) was applied in twelve PD patients to treat primarily motor deficits. Stimulation was applied percutaneously with quadripolar or octapolar electrodes. Clinical evaluation was assessed by the Unified Parkinson’s Disease Rating Scale (UPDRS) and the Hoehn and Yahr (H&Y) scale. Pain was evaluated by a visual analog scale. Evaluations of gait and of performance in a cognitive motor task were performed in some patients subjected to B-HCSCS. One patient who also suffered from severe autonomic cardiovascular dysfunction was investigated to evaluate the effectiveness of B-HCSCS on autonomic functions. Results: B-HCSCS was more effective and had more consistent effects than T-HCSCS in reducing pain. In addition, B-HCSCS improved UPDRS scores, including motor sub-items and tremor and H&Y score. Motor benefits appeared quickly after the beginning of B-HCSCS, in contrast to long latency improvements induced by T-HCSCS. A slight decrease of effectiveness was observed 12 months after implantation. B-HCSCS also improved gait and ability of patients to correctly perform a cognitive–motor task requiring inhibition of a prepared movement. Finally, B-HCSCS ameliorated autonomic control in the investigated patient. Conclusions: The results support a better usefulness of B-HCSCS compared to T-HCSCS in controlling pain and specific aspects of PD motor and non-motor deficits for at least one year.

Does fatigue in Parkinson's disease correlate with autonomic nervous system dysfunction?

BACKGROUND

Despite its negative impact on quality of life, fatigue in Parkinson's disease (PD) remains an under-recognized issue and the underlying pathology is undetermined.

OBJECTIVE

To contribute at understanding the pathogenesis of fatigue in a naturalistic cohort of cognitively intact PD patients.

METHODS

In a Caucasian population of PD patients (n = 27), we evaluated to what extent fatigue (quantified as PFS-16 score) is associated with PD duration and with autonomic dysfunction, studied by both MIBG scintigraphy and autonomic nervous system testing. The latter included the head-up tilt test, Valsalva maneuver, deep breathing, and handgrip tests.

RESULTS

PFS-16 score correlated with disease duration (R = 0.57, p = 0.002). Fatigue showed a clear correlation with deep breathing test (R = - 0.53, p = 0.004) but not with the MIBG H/M ratios.

CONCLUSIONS

Our data are consistent with a multifactorial pathogenesis of fatigue and with effects of dopamine depletion in PD-related fatigue; on the other hand, our findings do not support a role for sympathetic denervation in PD-related fatigue.

Rotigotine Improves Abnormal Circadian Rhythm of Blood Pressure in Parkinson's Disease

INTRODUCTION

Cardiovascular autonomic failure is commonly associated with Parkinson's disease (PD), affecting the daily lives of patients. Rotigotine was recently reported not to influence cardiovascular autonomic responses in contrast to other dopaminergic drugs. The effect of rotigotine on daily blood pressure (BP) fluctuations might reflect autonomic failure in patients with PD.

METHODS

Twenty-five PD patients who were receiving rotigotine and 12 patients not receiving rotigotine were recruited. Systolic BP during the daytime and nighttime was measured by 24-h BP monitoring at an interval of 2 years. The patients were divided into 3 groups according to the BP fluctuation type: dippers (nocturnal fall in BP ≥10%), non-dippers (0-10%), and risers (< 0%). The time course of BP was compared between the patients given rotigotine and those not given rotigotine.

RESULTS

Among the 25 patients who received rotigotine, the BP type worsened in 2 patients, was unchanged in 16 patients, and improved in 7 patients. Among the 12 patients who were not receiving rotigotine, the BP type worsened in 5 patients, was unchanged in 4 patients, and improved only in 3 patients (p = 0.042).

CONCLUSION

Rotigotine improves the abnormal circadian rhythm of BP in patients with PD. Rotigotine was suggested to have favorable effects on cardiovascular autonomic responses and circadian rhythm in patients with PD.

Efficacy and safety of rotigotine in elderly patients with Parkinson's disease in comparison with the non-elderly: a post hoc analysis of randomized, double-blind, placebo-controlled trials

Rotigotine—a non-ergot dopamine agonist—has two advantages; it can stimulate all dopamine receptors (D1–D5) like innate dopamine, and its transdermal administration provides continuous dopaminergic stimulation. The age of the patient impacts the effect and adverse events of anti-parkinsonian treatment. We conducted a post hoc analysis on three randomized, double-blind, placebo-controlled trials performed in Japan to clarify the difference of anti-parkinsonian treatment in elderly and non-elderly patients. Data from two combination therapy trials (with levodopa) in advanced stage Parkinson’s disease patients and one monotherapy trial in early stage patients were pooled and grouped by age (non-elderly aged < 70, elderly aged 70 +). In each age group, efficacy of rotigotine was compared to placebo. In the combination therapy, total Unified Parkinson’s Disease Rating Scale Part III scores and some subtotal scores, including those for tremor, akinesia and gait disturbance, significantly improved in both elderly and non-elderly patients. Regarding safety, the incidence of total adverse event tended to be lower in elderly patients than non-elderly patients, although it was not significant. No difference was observed in maintenance dosage of rotigotine between the two groups. In conclusion, the improvement in motor symptoms and frequency of adverse events were shown to be similar in elderly and non-elderly patients with rotigotine–levodopa combination therapy. Further, there was no major difference in maintenance dosage of rotigotine between the age groups. These results suggest good tolerability of rotigotine among elderly patients.

Autonomic dysfunction in subjects at high risk for Parkinson's disease

Aim of this project was to evaluate autonomic dysfunction in subjects proposed to be at high risk to develop Parkinson's disease (PD) compared to control subjects and PD patients at different disease stages. Combinations of substantia nigra hyperechogenicity (SN+) assessed by transcranial ultrasound (TCS), hyposmia, lifetime prevalence of depression and mild PD-specific motor signs were used to identify subjects at high risk for motor Parkinson's disease (HR-PD). Supine and standing blood pressure (BP), hearth rate (HR), orthostatic, urinary, sexual and bowel symptoms were evaluated in HR-PD, healthy control subjects and PD patients, divided into mild and advanced stages. The study group consisted of 113 PD patients (mild PD n = 71, advanced PD, n = 42), 40 HR-PD individuals and 50 controls. Compared to controls, HR-PD subjects complained more often about urinary (p = 0.002) and bowel dysfunction (p = 0.001) and had a higher diastolic BP drop after standing (p = 0.01). The cumulative number of autonomic symptoms differentiated PD as well as HR-PD significantly from controls (p < 0.001). Advanced PD patients presented often and severe orthostatic symptoms, not significantly different from mild PD after concomitant medication correction. Our results support the presence of urinary and bowel dysfunction in subjects at high risk for motor PD. Presence and severity of orthostatic symptoms was higher during stages and increase in advanced stages, at least partly due to increase in dopaminergic and conflicting medication. Understanding the progression of non-motor aspects in PD might offer the possibility to use them as targets for disease-modifying therapies.

Autonomic Function Tests and MIBG in Parkinson's Disease: Correlation to Disease Duration and Motor Symptoms

AIMS

Disorders of the autonomic nervous system (ANS) have a variable degree of clinical relevance in patients with Parkinson's disease (PD). Here, we assessed whether subclinical autonomic dysfunction, as evaluated by a complete battery of autonomic function tests (AFTs), correlates with PD progression.

METHODS

A series of 27 consecutive patients with PD underwent extensive ANS investigations including the head-up tilt test (HUTT), Valsalva maneuver, deep-breathing test, and handgrip test (HG); further, they performed 123I-meta-iodobenzylguanidine (MIBG) scintigraphy.

RESULTS

Seven of the 27 patients showed orthostatic hypotension (OH) at HUTT and pathological responses to the deep-breathing and HG test and Valsalva maneuver. The majority of the remaining 20 patients with PD showed pathological responses to deep-breathing (n = 13) and/or HG (n = 11). Only 3 of 27 suffered relevant OH. MIBG uptake of myocardium was decreased in 19 patients with PD (H/M ratio 1.3 ± 0.2). Prolonged clinical observation (>3 years), persistent response to levodopa, and MIBG repetition allowed us to exclude negative MIBG as attributable to atypical Parkinsonism. MIBG uptake did not correlate with OH and other AFTs. Both HG test response and MIBG did correlate with the Unified Parkinson's Disease Rating Scale (UPDRS) motor score and disease duration. A positive correlation emerged between diastolic blood pressure (DBP) response to HG test and MIBG and with systolic blood pressure (SBP) response at tilt test.

CONCLUSIONS

Our investigation suggests that ANS impairment affects the majority of patients with PD, even those PD patients showing negative MIBG, irrespective of clinical neurovegetative symptoms. The strict correlation that has been revealed with disease progression supports the routine utilization of AFTs as a reliable and inexpensive tool for monitoring peripheral sympathetic dysfunction in PD and optimizing therapy.

Risk of heart failure following treatment with dopamine agonists in Parkinson's disease patients

INTRODUCTION

Dopamine agonists (DAs) are frequently used to treat early or advanced Parkinson's disease (PD) patients. They have been shown to be efficacious for the treatment of motor symptoms and for delaying levodopa-induced dyskinesias. However, their utilization is limited by the risk of adverse drug reactions, some of which affect the cardiovascular system. Recently, the US FDA identified a possible association between exposure to pramipexole and the risk of heart failure.

AREAS COVERED

This article begins by reviewing the pharmacodynamic and cardiovascular effects of DAs on PD patients. Pharmacoepidemiological studies about the association between DAs and heart failure are then evaluated.

EXPERT OPINION

Four nested case-control studies were reviewed. In general, results showed higher heart failure risk following use of pramipexole or cabergoline. Although the effects of cabergoline may be explained by the induction of cardiac valve fibrosis, the basis for the significantly increased risk associated with pramipexole is unclear. It remains to be determined if these are dose-related effects, at what point they occur during the course of treatment, and if the risk is the same for all patients irrespective of other potential modifying factors, such as age and sex.