Chaudhuri's Dashboard of Vitals in Parkinson's syndrome: an unmet need underpinned by real life clinical tests

We have recently published the notion of the "vitals" of Parkinson's, a conglomeration of signs and symptoms, largely nonmotor, that must not be missed and yet often not considered in neurological consultations, with considerable societal and personal detrimental consequences. This "dashboard," termed the Chaudhuri's vitals of Parkinson's, are summarized as 5 key vital symptoms or signs and comprise of (a) motor, (b) nonmotor, (c) visual, gut, and oral health, (d) bone health and falls, and finally (e) comorbidities, comedication, and dopamine agonist side effects, such as impulse control disorders. Additionally, not addressing the vitals also may reflect inadequate management strategies, leading to worsening quality of life and diminished wellness, a new concept for people with Parkinson's. In this paper, we discuss possible, simple to use, and clinically relevant tests that can be used to monitor the status of these vitals, so that these can be incorporated into clinical practice. We also use the term Parkinson's syndrome to describe Parkinson's disease, as the term "disease" is now abandoned in many countries, such as the U.K., reflecting the heterogeneity of Parkinson's, which is now considered by many as a syndrome.

The pathophysiology of sexual dysfunction in Parkinson's disease: An overview

Sexual dysfunction is a common, poorly recognized, poorly discussed (often because of cultural perceptions and sensitivities), bothersome and neglected aspect of the range of non-motor symptoms of Parkinson's disease (PD). The spectrum of sexual dysfunction in PD ranges from hyposexuality-based disturbances to hypersexuality-dominated behaviors in the context of drug-induced impulse control disorder. The pathophysiological mechanisms underlying PD-related sexual dysfunction, specifically for hyposexual disorders, are thus heterogeneous and still not fully understood. However, central and peripheral neural mechanisms secondary to the hallmark pathological alterations of the disease (alpha-synuclein deposition and nigrostriatal degeneration) and to the associated network and neurotransmitter dysfunctions, together with the effects of dopaminergic therapies, seem to play an important role in the development of sexual disturbances. In this chapter, we therefore review the neuroanatomical and neurophysiological basis of sexual function in humans, and we provide insights on the pathophysiological mechanisms of hyposexuality and hypersexuality in PD.

Effects of Levodopa-Carbidopa Intestinal Gel on Dyskinesia and Non-Motor Symptoms Including Sleep: Results from a Meta-Analysis with 24-Month Follow-Up

BACKGROUND

In advanced Parkinson's disease (PD), dyskinesias and non-motor symptoms such as sleep dysfunction can significantly impair quality of life, and high-quality management is an unmet need.

OBJECTIVE

To analyze changes in dyskinesia and non-motor symptoms (including sleep) among studies with levodopa-carbidopa intestinal gel (LCIG) in patients with advanced PD.

METHODS

A comprehensive literature review identified relevant studies examining LCIG efficacy. Outcomes of interest were dyskinesia (UDysRS, UPDRS IV item 32), overall non-motor symptoms (NMSS), mentation/behavior/mood (UPDRS I), and sleep/daytime sleepiness (PDSS-2, ESS). The pooled mean (95% confidence interval) change from baseline per outcome was estimated for each 3-month interval with sufficient data (i.e., reported by≥3 studies) up to 24 months using a random-effects model.

RESULTS

Seventeen open-label studies evaluating 1243 patients with advanced PD were included. All outcomes of interest with sufficient data for meta-analysis showed statistically significant improvement within 6 months of starting LCIG. There were statistically significant improvements in dyskinesia duration as measured by UPDRS IV item 32 at 6 months (-1.10 [-1.69, -0.51] h/day) and 12 months (-1.35 [-2.07, -0.62] h/day). There were statistically and clinically significant improvements in non-motor symptoms as measured by NMSS scores at 3 months (-28.71 [-40.26, -17.15] points). Significant reduction of NMSS burden was maintained through 24 months (-17.61 [-21.52, -13.70] points). UPDRS I scores significantly improved at 3 months (-0.39 [-0.55, -0.22] points). Clinically significant improvements in PDSS-2 and ESS scores were observed at 6 and 12 months in individual studies.

CONCLUSION

Patients with advanced PD receiving LCIG showed significant sustained improvements in the burden of dyskinesia and non-motor symptoms up to 24 months after initiation.

Glucocorticoids in myocarditis therapy after COVID-19

 

The aim of the study - to evaluate the efficacy of glucocorticoids (GC) in patients with acute myocarditis (AM) after COVID-19 infection.

Material and methods

We included 60 pts with severe AM and heart failure (HF) with reduced (<40%) left ventricular (LV) ejection fraction (EF) who had COVID-19 infection 1–2 months before the enrollment. According to the results of cardiac magnetic resonance (CMR) included pts had ≥2 Lake Louise criteria for myocarditis. All pts on the background of HF therapy (β-blockers, ACE-inhibitors, MRA antagonists, diuretics) were prescribed GC: 0.25 mg/kg per day methylprednisolone for 3 months, followed by a gradual dose reduction of 1–2 mg per week until complete discontinuation after 6 months. Evaluation before the start of GC therapy and after 6 months included CMR, 2D- and speckle-tracking echocardiography.

Results

After 6 months according to the results of CMR the number of LV segments with inflammatory lesions decreased to (3,58±0,42) from (6,32±0,77) segments in average (p=0,001). This was followed by improvement of LV systolic function: increase of LV EF in average to (43,5±2,6) from (32,2±2,4) % (p=0,003), longitudinal global systolic strain (LGSS) absolute value to (11,3±1,1) from (7,9±0,5) % (p=0,012) and circumferential global systolic strain (CGSS) to (12,1±1,0) from (8,9±0,6) % (p=0,023). Also we observed LV volume reduction: decrease of LV end-diastolic (from 118,9±8,6 to 95,3±7,2 ml/m2, p=0,033) and LV end-systolic (from 80,1±5,1 to 59,1±4,4 ml/m2, p=0,027) volume indexes. Wherein in 24 of 60 pts (41,6%) on the background of significant decrease in the number of LV segments with inflammatory lesions (to 1,34±0,21 from 6,12±0,73 segments, p=0,0001) after 6 months we observed the recovery of LV EF ≥50%, followed by an improvement of LGSS and CGSS on 42,1 and 39,4% respectively (p=0,001). According to multivariate regression analysis, predictors of LV EF recovery (≥50%) after 6 months of GC treatment were established: presence of inflammatory lesions in ≤5,0 LV segments, values of LGSS and CGSS ≥9.0% and ≥9.5% respectively before the start of GC.

Conclusions

The use of GC in pts with severe AM after COVID-19 was followed by the decrease of LV segments number affected by inflammation, improvement of LV systolic function and reduction of LV volume indexes. In 41,6% of pts GC therapy was associated with LV EF recovery after 6 months and predictors of its effectiveness were found: presence of inflammatory lesions in ≤5,0 LV segments, values of LGSS and CGSS ≥9.0% and ≥9.5% respectively before the start of GC.

Funding Acknowledgement

Type of funding sources: None.

Constipation is Associated with Development of Cognitive Impairment in de novo Parkinson's Disease: A Longitudinal Analysis of Two International Cohorts

BACKGROUND

Constipation is regarded as one of the prodromal features of Parkinson's disease (PD) and there is emerging evidence linking gastrointestinal dysfunction and cognitive impairment (CI) in PD.

OBJECTIVE

We explored whether constipation is associated with development of CI in two independent cohorts of de novo PD patients (n = 196 from the Non-motor International Longitudinal Study [NILS] and n = 423 from the Parkinson's Progression Markers Initiative [PPMI] study).

METHODS

Constipation was clinically defined using the Non-Motor Symptoms Scale (NMSS) item-21 [NILS] and Scales for Outcomes in PD-Autonomic (SCOPA-AUT) item-5 [PPMI]. We assessed baseline group differences (PD with or without constipation) in CI, global non-motor symptoms burden, motor dysfunction, and striatal dopaminergic denervation. Kaplan-Meier method estimated group differences in cumulative proportion of patients with incident CI over three years. In PPMI, we subsequently performed univariate and multivariate Cox survival analyses to evaluate whether constipation predicts incident mild cognitive impairment or dementia over a 6-year period, including constipation and other known predictors of CI as covariates.

RESULTS

Patients with constipation had greater motor and global non-motor burden in both cohorts at baseline (p < 0.05). Kaplan-Meier plots showed faster conversion to CI in patients with constipation in both cohorts (p < 0.05). In PPMI, 37 subjects developed dementia during a mean follow-up of 4.9 years, and constipation was an independent predictor of dementia onset (hazard ratio = 2.311; p = 0.02).

CONCLUSION

Constipation in de novo PD patients is associated with development of cognitive decline and may serve as a clinical biomarker for identification of patients at risk for cognitive impairment.

Alzheimer's Disease and Parkinson Dementia Distinguished by Cognitive Marker

BACKGROUND

Temporary memory binding (TMB) has been shown to be specifically affected by Alzheimer's disease (AD) when it is assessed via free recall and titrating the task demands to equate baseline performance across patients.

METHODS

Patients with Parkinson's disease (PD) were subdivided into patients with and without cognitive impairment and compared with AD and amnestic mild cognitive impairment (aMCI) patients on their performance on the TMB.

RESULTS

The results show that only patients with AD dementia present with impaired TMB performance. Receiver operating characteristic curve analyses showed that TMB holds high sensitivity and specificity for aMCI and AD relative to PD groups and healthy controls.

CONCLUSION

The TMB is sensitive to the neurodegenerative mechanisms leading to AD dementia but not to those underpinning PD dementia. As such, TMB task can aid the differential diagnosis of these common forms of dementia.

Therapy of Parkinson's Disease Subtypes

Early descriptions of subtypes of Parkinson's disease (PD) are dominated by the approach of predetermined groups. Experts defined, from clinical observation, groups based on clinical or demographic features that appeared to divide PD into clinically distinct subsets. Common bases on which to define subtypes have been motor phenotype (tremor dominant vs akinetic-rigid or postural instability gait disorder types), age, nonmotor dominant symptoms, and genetic forms. Recently, data-driven approaches have been used to define PD subtypes, taking an unbiased statistical approach to the identification of PD subgroups. The vast majority of data-driven subtyping has been done based on clinical features. Biomarker-based subtyping is an emerging but still quite undeveloped field. Not all of the subtyping methods have established therapeutic implications. This may not be surprising given that they were born largely from clinical observations of phenotype and not in observations regarding treatment response or biological hypotheses. The next frontier for subtypes research as it applies to personalized medicine in PD is the development of genotype-specific therapies. Therapies for GBA-PD and LRRK2-PD are already under development. This review discusses each of the major subtyping systems/methods in terms of its applicability to therapy in PD, and the opportunities and challenges designing clinical trials to develop the evidence base for personalized medicine based on subtypes.

'Dopamine agonist Phobia' in Parkinson's disease: when does it matter? Implications for non-motor symptoms and personalized medicine

INTRODUCTION

Dopamine agonists have been widely used to treat patients with Parkinson's disease, but concerns related to their well-known side effects might prevent their use even when indicated. In this review, the authors describe for the first time the concept of 'Dopamine Agonist Phobia', a pharmacophobia that the authors believe might affect clinicians, and they provide evidence of the benefits of dopamine agonists, focusing on non-motor symptoms.

AREAS COVERED

The authors performed an extensive literature research, including studies exploring the use of dopamine agonists for the treatment of non-motor symptoms. The authors indicate the highest level of evidence in each section.

EXPERT OPINION

'Dopamine Agonist Phobia' may preclude valid therapeutic options in selected cases, specifically for the treatment of non-motor symptoms. Thus, the authors propose a personalized approach in Parkinson's disease treatment, and encourage a thoughtful use of dopamine agonists, rather than an overall nihilism.

Non-motor Parkinson disease: new concepts and personalised management

Most patients with Parkinson disease (PD) have non-motor symptoms (NMS), and on average these can range from four to 19 different symptoms. NMS dominate the prodromal phase of PD and some may serve as clinical biomarkers of PD. NMS can be dopaminergic, non-dopaminergic, of genetic origin or drug induced. Clinical assessment of NMS should include the NMS Questionnaire (completed by patients) for screening, as recommended by the International Parkinson and Movement Disorders Society and other international societies. The total number of NMS in a patient with PD constitutes the NMS burden, which can be graded using validated cut-off scores on the NMS Questionnaire and Scale and can be used as an outcome measure in clinical trials. Despite NMS burden having a major effect on the quality of life of patients and carers, a large European study showed that NMS are often ignored in the clinic. The syndromic nature of PD is underpinned by non-motor subtypes which are likely to be related to specific dysfunction of cholinergic, noradrenergic, serotonergic pathways in the brain, not just the dopaminergic pathways. NMS can be treated by dopaminergic and non-dopaminergic strategies, but further robust studies supported by evidence from animal models are required. The future of modern treatment of PD needs to be supported by the delivery of personalised medicine.

Societal Burden and Persisting Unmet Needs of Parkinson’s Disease

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Advanced Parkinson's or "complex phase" Parkinson's disease? Re-evaluation is needed

Holistic management of Parkinson’s disease, now recognised as a combined motor and nonmotor disorder, remains a key unmet need. Such management needs relatively accurate definition of the various stages of Parkinson’s from early untreated to late palliative as each stage calls for personalised therapies. Management also needs to have a robust knowledge of the progression pattern and clinical heterogeneity of the presentation of Parkinson’s which may manifest in a motor dominant or nonmotor dominant manner. The “advanced” stages of Parkinson’s disease qualify for advanced treatments such as with continuous infusion or stereotactic surgery yet the concept of “advanced Parkinson’s disease” (APD) remains controversial in spite of growing knowledge of the natural history of the motor syndrome of PD. Advanced PD is currently largely defined on the basis of consensus opinion and thus with several caveats. Nonmotor aspects of PD may also reflect advancing course of the disorder, so far not reflected in usual scale based assessments which are largely focussed on motor symptoms. In this paper, we discuss the problems with current definitions of “advanced” PD and also propose the term “complex phase” Parkinson’s disease as an alternative which takes into account a multimodal symptoms and biomarker based approach in addition to patient preference.

Non-Motor Symptoms Assessed by Non-Motor Symptoms Questionnaire and Non-Motor Symptoms Scale in Parkinson's Disease in Selected Asian Populations

Background: Ethnic variations have been described in medical conditions, such as hypertension, diabetes, and multiple sclerosis. Whether ethnicity plays a role in Parkinson's disease (PD), particularly with regard to non-motor symptoms (NMS), remains unclear. Existing literature is diverse, controversial, and inadequately documented. This review aims to analyse and report the currently available literature on NMS, specifically in Asian PD patients. Summary: We conducted a literature review using PubMed, searching for articles and currently available publications that reference and assess NMS in PD patients living in Asia using the validated NMS Questionnaire (NMS Quest) and NMS Scale (NMSS). In total, 24 articles were included: 12 using the NMS Quest and 12 using the NMSS. Symptoms of constipation, memory impairment, and nocturia were the most frequently self-reported symptoms (NMS Quest) in selected Asian populations, while symptoms within the domains sleep/fatigue, attention/memory, and mood/apathy were most prevalent when applying the health-professional completed NMSS. Key Messages: NMS are generally prevalent and highly burdensome within selected Asian PD populations living in countries included in this review. Our review suggests that NMS-driven phenotypic heterogeneity is present in Asian patients, and compared to Western PD populations there might be variations in assessed NMS.

Nonmotor Symptoms in Experimental Models of Parkinson's Disease

Nonmotor symptoms of Parkinson's disease (PD) range from neuropsychiatric, cognitive to sleep and sensory disorders and can arise from the disease process as well as from drug treatment. The clinical heterogeneity of nonmotor symptoms of PD is underpinned by a wide range of neuropathological and molecular pathology, affecting almost the entire range of neurotransmitters present in brain and the periphery. Understanding the neurobiology and pathology of nonmotor symptoms is crucial to the effective treatment of PD and currently a key unmet need. This bench-to-bedside translational concept can only be successful if robust animal models of PD charting the genesis and natural history of nonmotor symptoms can be devised. Toxin-based and transgenic rodent and primate models of PD have given us important clues to the underlying basis of motor symptomatology and in addition, can provide a snapshot of some nonmotor aspects of PD, although the data are far from complete. In this chapter, we discuss some of the nonmotor aspects of the available experimental models of PD and how the development of robust animal models to understand and treat nonmotor symptoms needs to become a research priority.

Nonmotor Parkinson's and Future Directions

Nonmotor symptoms (NMS) of Parkinson's disease (PD) are integral to the condition largely regarded as a motor syndrome. A range of NMS underpin the prodromal stage of Parkinson's and are present with variable frequency, range, and nature across the whole journey of a patient with Parkinson's from the onset of the motor disease to palliative stage. These symptoms also are key determinants of quality of life of the patient as well as the carer. Despite this, recognition management and focused treatment of NMS of PD remain poor. Future would, therefore, need to focus on better definition and management of NMS of PD. This would include development of robust animal models of specific NMS such as cognitive, sleep, and autonomic dysfunctions as well as pain to understand the mechanistic pathways of these symptoms. In turn this will lead to better drug development using a bench to bedside model. Nonmotor clinical subtypes of PD have also been described and, in future, proper biomarkers will consolidate these findings in addition to defining the natural history of the subtypes. Revised versions of established scales and questionnaires will enable the adoption of good clinical practice with recognition of these subtypes in clinic. This will enhance the delivery of true subtype-specific therapies. Drug development should also include nondopaminergic and cell replacement restorative therapies with a nonmotor focus. An additional key area of future research would be the formalizing of true personalized medicine for PD. Personalized medicine pathways should concentrate on the role of exercise, complementary medicine as well as age, body weight, ethnicity on various NMS of PD. Genetics and pharmacogenetic developments in PD will add to the precision of the individualized approach.

The Epidemiology of Nonmotor Symptoms in Parkinson's Disease (Cohort and Other Studies)

Nonmotor symptoms (NMS) of Parkinson's disease (PD) were recognized by James Parkinson himself and are now considered to be an integral part of PD. While clinical assessment had focused on prevalence and severity of individual NMS such as dementia and depression, work in the last decade has concentrated on global or holistic assessment of NMS using validated tools such as the NMS questionnaire and NMS scale. These studies from cohorts of varying sizes have allowed comparison of NMS across different disease stages, duration, age, and ethnicity in PD. The data also allow exploration of the concept of the nonlinear relationship of NMS to disease duration of PD and motor stages as well as nonmotor subtypes of PD. In this chapter, these aspects of epidemiological studies of NMS in PD cohorts are described.

Biomarkers of Parkinson's Disease: An Introduction

The development of biomarkers is of great importance in Parkinson's disease (PD) as it may contribute to confirmation and support of the diagnosis, tracking of progression, and prediction of the natural history of PD. Biomarkers also help in the identification of targets for treatment and measuring the efficacy of interventions. Biomarkers are, therefore, crucial to understanding the pathophysiology of PD, the second commonest neurodegenerative disorder in the world. Modern understanding of PD suggests that it is a multipeptide, multiorgan disorder presenting with a heterogeneous clinical condition, both motor and nonmotor. Biomarkers need to reflect this neuropathological and clinical heterogeneity of PD. In this review, we outline some key advances in the field of clinical, genetic, neuroimaging, and tissue-based biomarkers proposed or used for PD. The individual sections will be covered in relevant chapters and our review is largely a primer aimed to alert readers to the current state of the various biomarkers proposed for PD. In doing so, we have also underlined the important role multimodal rather than single biomarkers could play in our future understanding of PD.

Intrajejunal levodopa infusion therapy for Parkinson's disease: practical and pragmatic tips for successful maintenance of therapy

INTRODUCTION

Intrajejunal levodopa infusion (IJLI) therapy is one of the most influential therapies in moderate to late stage Parkinson's disease with documented effects on motor and nonmotor symptoms and quality of life. The process of initiation and maintenance of therapy however, remains a challenge particularly in the long term. Areas covered: The authors reviewed 'evidence base' for pathways and advice given to patients pre and post IJLI initiation. The authors found lack of patient, carer and clinician led 'real life' advisory documents which need to be given to patients on IJLI. Expert commentary: Experience from centers engaged in IJLI therapy as well as feedback from carers and patients on IJLI suggest wide variability of practical advice given to patients. This is important as such tips could avoid termination of treatment or serious adverse events in some cases. In this review the authors provide a collection of pragmatic and practical tips for patients initiated on IJLI, both related to the short and long term and which we believe is a key unmet need. The paper is illustrated with two case reports.

Palliative Care for Patients and Families With Parkinson's Disease

Parkinson's disease is the second most common neurodegenerative disease worldwide. There is widespread consensus that Parkinson patients, their carers, and clinicians involved in their care would benefit from a fully integrated, need-based provision of palliative care. However, the concept of palliative care in Parkinson's disease is still poorly defined and, consequently, poorly implemented into daily clinical practice. A particular challenge is the gradually progressive nature of Parkinson's disease-with insidiously increasing disability-making it challenging to clearly define the onset of palliative care needs for Parkinson patients. As people with Parkinson's disease are now living longer than in the past, future research needs to develop a more robust evidence-based approach to clarify the disease events associated with increased palliative care needs, and to examine these, prospectively, in an integrated palliative care service. The modern palliative care outlook, termed "simultaneous care,",is no longer restricted to the final stage of disease. It involves incorporating a continuity of care, effective management of the chronic-palliative interface, and a multidisciplinary network of professionals working both in the community and in specialized clinics, with active involvement of caregivers. Although promising, there is still a need to demonstrate the effectiveness of palliative care for patients with Parkinson's disease.

The Future of Parkinson’s Treatment – Personalised and Precision Medicine

The modern concept of Parkinson’s disease (PD) has changed and evolved and we consider Parkinson’s to be a multi-neurotransmitter dysfunction-related disorder with central and peripheral nervous system involvement. The clinical expression is thus a mixture of the outwardly evident motor symptoms and a range of ‘hidden’ non-motor symptoms. The complex underlying neuropathology of PD calls for a reassessment of the treatment strategies currently used. Treatment of PD is guideline-driven and in most cases based on a dopamine replacement strategy or surgical manipulation of brain dopaminergic pathways. Treatment of many non-dopaminergic non-motor and some motor symptoms, which have major effects on quality of life, continue to remain a key unmet need. Like in other chronic conditions such as rheumatology, the role of personalised medicine in PD needs to be increasingly considered. Personalised medicine for PD is not just a genetic approach to treatment but encompasses various strands of treatment. These include pharmacogenetic, pharmacological, as well as socio-demographic and lifestyle-related issues. Once these ‘enablers’ of personalised medicine are considered then satisfactory treatment for our patients with Parkinson’s can be achieved in an individualised manner. Future therapy for PD should move in that direction.

Parkinson's: a syndrome rather than a disease?

Emerging concepts suggest that a multitude of pathology ranging from misfolding of alpha-synuclein to neuroinflammation, mitochondrial dysfunction, and neurotransmitter driven alteration of brain neuronal networks lead to a syndrome that is commonly known as Parkinson’s disease. The complex underlying pathology which may involve degeneration of non-dopaminergic pathways leads to the expression of a range of non-motor symptoms from the prodromal stage of Parkinson’s to the palliative stage. Non-motor clinical subtypes, cognitive and non-cognitive, have now been proposed paving the way for possible subtype specific and non-motor treatments, a key unmet need currently. Natural history of these subtypes remains unclear and need to be defined. In addition to in vivo biomarkers which suggest variable involvement of the cholinergic and noradrenergic patterns of the Parkinson syndrome, abnormal alpha-synuclein accumulation have now been demonstrated in the gut, pancreas, heart, salivary glands, and skin suggesting that Parkinson’s is a multi-organ disorder. The Parkinson’s phenotype is thus not just a dopaminergic motor syndrome, but a dysfunctional multi-neurotransmitter pathway driven central and peripheral nervous system disorder that possibly ought to be considered a syndrome and not a disease.

Preattentive voice discrimination by the human brain as indexed by the mismatch negativity

The goal of the present study was to determine whether the mismatch negativity (MMN), a component of the auditory event-related potential (ERPs) indexing perceptual difference between any two sounds, could be used as an objective measure of speaker discriminability and similarity/dissimilarity. ERPs were recorded in response to natural speech sounds from subjects watching a silent video. The stimuli consisted of a sequence of repetitive 'standard' sounds (the vowel /e/ pronounced by a female voice), which was infrequently interspersed with 'deviant' stimuli; the same /e/vowel pronounced by different speakers (one male and three females). Voice intensity and duration were matched between all the voices used. A separate behavioural discrimination task measured the perceptual distance of each deviant voice from the standard voice through pair-wise dissimilarity ratings. The MMN was elicited by all deviant voices. Furthermore, the dissimilarity ratings on the behavioural task paralleled the preattentive discrimination as indexed by the MMN amplitude. These results suggest that the MMN could be used as an objective measure of voice similarity/dissimilarity, and thus could serve objective speaker recognition.