The impact of autonomic dysfunction on survival in patients with dementia with Lewy bodies and Parkinson's disease with dementia

Brain white matter changes and their associations with non-motor dysfunction in orthostatic hypotension in α-synucleinopathy: A NODDI study

BACKGROUND

The specific non-motor symptoms associated with α-synucleinopathies, including orthostatic hypotension (OH), cognitive impairment, and emotional abnormalities, have been a subject of ongoing controversy over the mechanisms underlying the development of a vicious cycle among them. The distinct structural alterations in white matter (WM) in patients with α-synucleinopathies experiencing OH, alongside their association with other non-motor symptoms, remain unexplored. This study employs axial diffusivity and density imaging (NODDI) to investigate WM damage specific to α-synucleinopathies with concurrent OH, delivering fresh evidence to supplement our understanding of the pathogenic mechanisms and pathological rationales behind the occurrence of a spectrum of non-motor functional impairments in α-synucleinopathies.

METHODS

This study recruited 49 individuals diagnosed with α-synucleinopathies, stratified into an α-OH group (n = 24) and an α-NOH group (without OH, n = 25). Additionally, 17 healthy controls were included for supine and standing blood pressure data collection, as well as neuropsychological assessments. Magnetic resonance imaging (MRI) was utilized for the calculation of NODDI parameters, and tract-based spatial statistics (TBSS) were employed to explore differential clusters. The fibers covered by these clusters were defined as regions of interest (ROI) for the extraction of NODDI parameter values and the analysis of their correlation with neuropsychological scores.

RESULTS

The TBSS analysis unveiled specific cerebral regions exhibiting disparities within the α-OH group as compared to both the α-NOH group and the healthy controls. These differences were evident in clusters that indicated a decrease in the acquisition of the neurite density index (NDI), a reduction in the orientation dispersion index (ODI), and an increase in the isotropic volume fraction (FISO) (p < 0.05). The extracted values from these ROIs demonstrated significant correlations with clinically assessed differences in supine and standing blood pressure, overall cognitive scores, and anxiety-depression ratings (p < 0.05).

CONCLUSION

Patients with α-synucleinopathies experiencing OH exhibit distinctive patterns of microstructural damage in the WM as revealed by the NODDI model, and there is a correlation with the onset and progression of non-motor functional impairments.

Association between autonomic dysfunction with motor and non-motor symptoms in patients with Parkinson's disease

To investigate the association between autonomic dysfunction (AutD) and motor as well as non-motor symptoms (NMS) in patients with Parkinson's disease (PD). Fifty-three PD patients were divided into two groups based on the number of domains affected by AutD: a multi-domain AutD group (AutD-M) and a single-domain AutD group (AutD-S), as evaluated using the Scale for Outcomes in Parkinson's disease-Autonomic (SCOPA-AUT), which assesses autonomic symptoms, one of the NMS. A comprehensive comparison was conducted between the two groups, including clinical measures such as clinical scales, quantitative evaluations of motor function and exercise capacity. Spearman correlation analysis was employed to investigate the relationship between AutD severity and PD symptoms. Additionally, we performed multiple linear regression model analysis to determine whether associations between SCOPA-AUT scores and clinical assessments remained significant after adjusting for Hoehn and Yahr stage, sex, and age. PD patients in the AutD-M group exhibited significantly more severe NMS and motor symptoms compared to those in the AutD-S group. In correlation analysis, SCOPA-AUT scores showed significant correlations with multiple clinical symptoms, such as most of the NMS, 10-MWT and CPET parameters. Furthermore, regression analysis also revealed that more pronounced fatigue, anxiety, depressive symptoms, worse walking speed and impaired exercise capacity were associated with higher SCOPA-AUT scores. The presence of AutD is correlated with emotional disturbances, decreased exercise endurance, and impaired gait function in patients with PD. Early management of AutD may prove beneficial in alleviating some NMS and motor symptoms in PD.

Impact of autonomic symptoms on the clinical course of Parkinson's disease

PURPOSE

Patients with Parkinson's disease (PD) exhibit various degrees of autonomic symptoms, which may be associated with Lewy body pathology distributed extensively in the autonomic nervous system. We hypothesized that the severity of autonomic symptoms reflects the severity of PD-related pathology, resulting in poor outcomes. The purpose of this study was to evaluate the impact of autonomic symptoms on PD progression.

METHODS

We conducted a follow-up study among consecutive patients with PD at Dokkyo Medical University Hospital. Patients underwent comprehensive baseline evaluations and were classified into high and low autonomic symptom groups using the Scale for Outcomes in Parkinson's Disease-Autonomic (SCOPA-AUT). The Kaplan‒Meier survival curves were used to analyze the time to discontinuation of their visits because of PD-related endpoints and to evaluate the association with high SCOPA-AUT scores.

RESULTS

Of the 101 patients, 74 (73%) met the inclusion criteria. During the follow-up period (mean 1654 days), 22/74 patients reached PD-related endpoints (death, 4; hospitalization, 9; nursing home institutionalization, 9). PD patients with high SCOPA-AUT scores reached the endpoints faster than those with low SCOPA-AUT scores. A high SCOPA-AUT score, including gastrointestinal, urinary, and thermoregulation domains; high motor symptom scores; and low specific binding ratios (SBRs) on 123I FP-CIT-SPECT (DAT-SPECT) were associated with reaching PD-related endpoints. A high SCOPA-AUT score was associated with reaching the endpoints even after adjustment for covariates.

CONCLUSIONS

Patients with high autonomic symptom scores had a greater risk of reaching PD-related endpoints than patients with low autonomic symptom scores.

Synchronous monitoring of brain-heart electrophysiology using heart rate variability coupled with rapid quantitative electroencephalography in orthostatic hypotension patients with α-synucleinopathies: Rapid prediction of orthostatic hypotension and preliminary exploration of brain stimulation therapy

BACKGROUND

In α-synucleinopathies, the dysfunction of the autonomic nervous system which typically manifests as orthostatic hypotension (OH) often leads to severe consequences and poses therapeutic challenges. This study aims to discover the brain-cardiac electrophysiological changes in OH patients with α-synucleinopathies using the rapid quantitative electroencephalography (qEEG) coupled with heart rate variability (HRV) technique to identify rapid, noninvasive biomarkers for early warning and diagnosis, as well as shed new light on complementary treatment approaches such as brain stimulation targets.

METHODS

In this study, 26 subjects of α-synucleinopathies with OH (α-OH group), 21 subjects of α-synucleinopathies without OH (α-NOH group), and 34 healthy controls (control group) were included from September 2021 to August 2023 (NCT05527067). The heart rate-blood pressure variations in supine and standing positions were monitored, and synchronization parameters of seated resting-state HRV coupled with qEEG were collected. Time-domain and frequency-domain of HRV measures as well as peak frequency and power of the brainwaves were extracted. Differences between these three groups were compared, and correlations between brain-heart parameters were analyzed.

RESULTS

The research results showed that the time-domain parameters such as MxDMn, pNN50, RMSSD, and SDSD of seated resting-state HRV exhibited a significant decrease only in the α-OH group compared to the healthy control group (p < 0.05), while there was no significant difference between the α-NOH group and the healthy control group. Several time-domain and frequency-domain parameters of seated resting-state HRV were found to be correlated with the blood pressure changes within the first 5 min of transitioning from supine to standing position (p < 0.05). Differences were observed in the power of beta1 waves (F4 and Fp2) and beta2 waves (Fp2 and F4) in the seated resting-state qEEG between the α-OH and α-NOH groups (p < 0.05). The peak frequency of theta waves in the Cz region also showed a difference (p < 0.05). The power of beta2 waves in the Fp2 and F4 brain regions correlated with frequency-domain parameters of HRV (p < 0.05). Additionally, abnormal electrical activity in the alpha, theta, and beta1 waves was associated with changes in heart rate and blood pressure within the first 5 min of transitioning from supine to standing position (p < 0.05).

CONCLUSION

Rapid resting-state HRV with certain time-domain parameters below normal levels may serve as a predictive indicator for the occurrence of orthostatic hypotension (OH) in patients with α-synucleinopathies. Additionally, the deterioration of HRV parameters correlates with synchronous abnormal qEEG patterns, which can provide insights into the brain stimulation target areas for OH in α-synucleinopathy patients.

Chronotropic Incompetence in Parkinson's Disease: A Possible Marker of Severe Disease Phenotype?

Autonomic dysfunction is a prevalent feature of Parkinson's disease (PD), mediated by disease involvement of the autonomic nervous system. Chronotropic incompetence (CI) refers to inadequate increase of heart rate in response to elevated metabolic demand, partly dependent on postganglionic sympathetic tone. In a retrospective study, PD patients with/without CI were identified. We show that PD with CI was associated with a higher levodopa equivalent daily dose and Hoehn and Yahr stage, 5±2 years after motor onset. Our data support a putative role of CI as a clinical marker of a more severe disease phenotype, possibly reflecting more widespread alpha-synuclein pathology.

Autonomic dysfunction is associated with disease progression and survival in amyotrophic lateral sclerosis: a prospective longitudinal cohort study

BACKGROUND

Among non-motor symptoms, autonomic disturbances have been described in amyotrophic lateral sclerosis (ALS) and reported as mild to moderate in up to 75% of patients. However, no study has systematically investigated autonomic symptoms as prognostic factors.

OBJECTIVES

The main aim of this longitudinal study was to examine the association of autonomic dysfunction with disease progression and survival in ALS.

METHODS

We enrolled newly diagnosed ALS patients and a healthy control group (HC). Time from disease onset to disease milestone (King's stage 4) and death were calculated to assess disease progression and survival. Autonomic symptoms were assessed by a dedicated questionnaire. Longitudinal evaluation of parasympathetic cardiovascular activity was performed by the heart rate variability (HRV). Multivariable Cox proportional hazards regression models on the risk of the disease milestone and death were used. A mixed-effect linear regression model was used to compare autonomic dysfunction with a HC group as well as its impairment over time.

RESULTS

A total of 102 patients and 41 HC were studied. ALS patients, compared with HC, complained of more autonomic symptoms, especially in bulbar onset patients. Autonomic symptoms occurred in 69 (68%) patients at diagnosis and progressed over time (post-6: p = 0.015 and post-12: p < 0.001). A higher autonomic symptom burden was an independent marker of faster development of King's stage 4 (HR 1.05; 95% CI 1.00-1.11; p = 0.022); whereas, urinary complaints were independent factors of a shorter survival (HR 3.12; 95% CI 1.22-7.97; p = 0.018). Moreover, HRV in ALS patients was lower than in HC (p = 0.018) and further decreased over time (p = 0.003), implying a parasympathetic hypofunction that progressed over time.

CONCLUSION

Autonomic symptoms occur in most of the ALS patients at diagnosis and progress over time, implying that autonomic dysfunction represents an intrinsic non-motor feature of the disease. A higher autonomic burden is a poor prognostic factor, associated with a more rapid development of disease milestones and shorter survival.

Investigation of Autonomic Dysfunction in Alzheimer's Disease-A Computational Model-Based Approach

(1) Background and Objective: Alzheimer's disease (AD) is commonly accompanied by autonomic dysfunction. Investigating autonomic dysfunction's occurrence patterns and severity may aid in making a distinction between different dementia subtypes, as cardiac autonomic dysfunction and AD severity are correlated. Heart rate variability (HRV) allows for a non-invasive assessment of the autonomic nervous system (ANS). AD is characterized by cholinergic depletion. A computational model of ANS based on the kinetics of acetylcholine and norepinephrine is used to simulate HRV for various autonomic states. The model has the flexibility to suitably modulate the concentration of acetylcholine corresponding to different autonomic states. (2) Methods: Twenty clinically plausible AD patients are compared to 20 age- and gender-matched healthy controls using HRV measures. Statistical analysis is performed to identify the HRV parameters that vary significantly in AD. By modulating the acetylcholine concentration in a controlled manner, different autonomic states of Alzheimer's disease are simulated using the ANS model. (3) Results: In patients with AD, there is a significant decrease in vagal activity, sympathovagal imbalance with a dominant sympathetic activity, and change in the time domain, frequency domain, and nonlinear HRV characteristics. Simulated HRV features corresponding to 10 progressive states of AD are presented. (4) Conclusions: There is a significant difference in the HRV features during AD. As cholinergic depletion and autonomic dysfunction have a common neurological basis, autonomic function assessment can help in diagnosis and assessment of AD. Quantitative models may help in better comprehending the pathophysiology of the disease and assessment of its progress.

Cognitive Impairment in Neurodegenerative Movement Disorders

Patients with neurodegenerative movement disorders can develop cognitive impairment during the disease. Cognitive symptoms have been associated with decreased quality of life, higher caregiver burden, and earlier institutionalization, and are therefore critical for physicians to understand and address. The evaluation of cognitive performance of patients with neurodegenerative movement disorders is important for providing adequate diagnosis, management, prognosis, and support patients and their caregivers. In this review, we discuss the features of the cognitive impairment profile of commonly encountered movement disorders: Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy, corticobasal syndrome, and Huntington's disease. In addition, we provide neurologists with practical guidance and evaluation tools for the assessment and management of these challenging patients.

Assessment of clinical features and coexisting geriatric syndromes in newly diagnosed dementia with Lewy bodies: a retrospective study in a tertiary geriatrics setting in Turkey

PURPOSE

Identifying the associated clinical conditions in patients with newly diagnosed dementia with Lewy bodies (DLB) may contribute to the disease management. This study aimed to examine the clinical features and coexisting geriatric syndromes of patients with newly diagnosed DLB.

METHOD

This cross-sectional study included newly diagnosed DLB participants who were admitted to a tertiary geriatric outpatient clinic. Of the 857 patients with dementia, 116 DLB diagnoses were eligible for analysis. The core and supportive clinical features of DLB were recorded. Geriatric syndromes including polypharmacy, depression, insomnia, dependency, a history of delirium, falls, malnutrition, urinary incontinence, functional impairment, and living alone, were assessed and recorded at baseline.

RESULTS

The mean age was 79.0 ± 6.9 years, and 50.9% of the participants were female. The majority (63.8%) had mild dementia, 31.9% had moderate, and 4.3% had severe disease. Cognitive fluctuations (78.4%), visual hallucinations (77.6%), and Parkinsonism (73.3%) were the most common clinical features. Functional impairment (59.5%) and urinary incontinence (59.5%) were the leading geriatric syndromes, followed by polypharmacy (56.9%), depressive symptoms (54.7%), falls (52.6%), insomnia (49.1%), malnutrition (24.3%), and delirium (6.0%). Women had more functional impairment and depressive symptoms than men.

CONCLUSION

Although most patients had mild dementia, three-quarters of the DLB cohort had hallucinations, and nearly two-thirds were functionally impaired. The proportion of other serious health conditions also increased, indicating a high comorbidity and geriatric syndrome burden. Comprehensive geriatric assessment is strongly recommended for DLB patients from the time of diagnosis until death to reduce disability and comorbidities.

THE CLINICAL TRIAL REGISTRATION NUMBER

NCT05052450.

Psychometric properties of the Autonomic Symptoms Checklist in the Lewy body disease module of the uniform dataset

INTRODUCTION

Autonomic dysfunction is an important feature of Lewy Body Dementia (DLB), but measurement of autonomic symptoms has been limited in both previous research and clinical practice. Accurate measurement of autonomic dysfunction has the potential to improve our understanding of the course and progression of DLB, given that autonomic symptoms typically precede cognitive impairment and are associated with functional impairment. The primary aim of this study was to examine the psychometric properties of the two versions (3.0 and 3.1) of the NACC LBD-module Autonomic Symptom Checklist (ASC).

METHODS

Psychometric analyses of the ASC (internal consistency, reliability, factor structure, and validity) were conducted on data acquired from 245 individuals with DLB from the NACC database. ASC V3.0 was contrasted on these attributes to V3.1.

RESULTS

Results suggested an underlying factor structure for the ASC, and confirmatory factor analysis (CFA) revealed 3 factors, which generally aligned with discrete autonomic systems. The ASC V3.0 and CFA-identified scales were comparable in terms of reliability, which were both improved relative to the ASC V3.1. In terms of ecological validity, CFA-identified items related to gastrointestinal/thermoregulation symptoms were significantly more associated with functional outcomes compared to the unitary ASC.

CONCLUSION

Findings underscore the importance of differentiation within the autonomic system. Future research into autonomic symptom classes and lab-based pathophysiological measurement of autonomic dysfunction in DLB has the potential to support early identification and inform treatment planning.

Abnormal circadian blood pressure regulation and cognitive impairment in α-synucleinopathies

Circadian blood pressure (BP) rhythm is important for the maintenance of healthy daily life, and its disruption is associated with poor outcomes. Cardiovascular autonomic failure is often observed in older populations but has a greater impact on neurodegenerative disorders such as α-synucleinopathies. These BP abnormalities include orthostatic hypotension (OH), supine hypertension (SH), and a loss of nocturnal BP fall. OH not only causes falls or syncope but is also related to cognitive impairment in α-synucleinopathies. For example, OH doubles or triples the risk for the development of cognitive impairment in Parkinson's disease (PD). The diffuse central and peripheral neuropathology of α-synuclein may contribute to both OH and cognitive impairment. Moreover, repeated cerebral hypoperfusion in OH is thought to be related to cerebrovascular and neuronal damage, which may cause cognitive impairment. SH, which often coexists with OH, is also associated with cognitive impairment through cerebrovascular damage, such as white matter lesions and cerebral microbleeds. The reverse-dipping (riser) pattern on ambulatory BP monitoring is commonly observed in PD (∼56%), regardless of disease duration and severity. It is also related to cognitive impairment and more pronounced when coexisting with OH. These abnormal circadian BP profiles may be synergistically associated with cognitive impairment and poor outcomes in α-synucleinopathies. Although evidence for aggressive control of BP dysregulation improving cognitive impairment and outcomes is limited, regular BP monitoring appears to be important for total management of α-synucleinopathies.

Degenerative dementias: A question of syndrome or disease?

BACKGROUND

Neurologists refer to numerous "syndromes,‿ consisting of specific combinations of clinical manifestations, following a specific progression pattern, and with the support of blood analysis (without genomic-proteomic parameters) and neuroimaging findings (MRI, CT, perfusion SPECT, or 18F-FDG-PET scans). Neurodegenerative "diseases,‿ on the other hand, are defined by specific combinations of clinical signs and histopathological findings; these must be confirmed by a clinical examination and a histology study or evidence of markers of a specific disorder for the diagnosis to be made. However, we currently know that most genetic and histopathological alterations can result in diverse syndromes. The genetic or histopathological aetiology of each syndrome is also heterogeneous, and we may encounter situations with pathophysiological alterations characterising more than one neurodegenerative disease. Sometimes, specific biomarkers are detected in the preclinical stage.

DEVELOPMENT

We performed a literature review to identify patients whose histopathological or genetic disorder was discordant with that expected for the clinical syndrome observed, as well as patients presenting multiple neurodegenerative diseases, confirming the heterogeneity and overlap between syndromes and diseases. We also observed that the treatments currently prescribed to patients with neurodegenerative diseases are symptomatic.

CONCLUSIONS

Our findings show that the search for disease biomarkers should be restricted to research centres, given the lack of disease-modifying drugs or treatments improving survival. Moreover, syndromes and specific molecular or histopathological alterations should be managed independently of one another, and new "diseases‿ should be defined and adapted to current knowledge and practice.

Recent advances in Lewy body dementia: A comprehensive review

Lewy Body Dementia is the second most frequent neurodegenerative illness proven to cause dementia, after Alzheimer's disease (AD). It is believed to be vastly underdiagnosed, as there is a significant disparity between the number of cases diagnosed clinically and those diagnosed via neuropathology at the time of postmortem autopsy. Strikingly, many of the pharmacologic treatments used to treat behavioral and cognitive symptoms in other forms of dementia exacerbate the symptoms of DLB. Therefore, it is critical to accurately diagnose DLB as these patients require a specific treatment approach. This article focuses on its pathophysiology, risk factors, differentials, and its diverse treatment modalities. In this study, an English language literature search was conducted on Medline, Cochrane, Embase, and Google Scholar till April 2022. The following search strings and Medical Subject Headings (MeSH) terms were used: "Lewy Body Dementia," "Dementia with Lewy bodies," and "Parkinson's Disease Dementia." We explored the literature on Lewy Body Dementia for its epidemiology, pathophysiology, the role of various genes and how they bring about the disease, biomarkers, its differential diagnoses and treatment options.

Current Therapies and Drug Development Pipeline in Lewy Body Dementia: An Update

The term Lewy body dementia refers to either of two related diagnoses: dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). Clinical management of Lewy body dementia is challenging. The current treatment options focus on relieving symptoms; no disease-modifying therapies are available. There are currently no US Food and Drug Administration (FDA) approved drugs for the treatment of DLB, and there are only a few for PDD. Cholinesterase inhibitors are shown to be beneficial in improving cognitive symptoms in Lewy body dementia. Rivastigmine was approved by the FDA to treat PDD. Donepezil was approved in Japan as a treatment for DLB. Levodopa may provide modest benefit in treating motor symptoms and zonisamide in adjunct to low-dose levodopa helps with parkinsonism. Treatment of autonomic symptoms are based on symptomatic treatment with off-label agents. Our main objective in this article is to present an overview of the current pharmacological options available to treat the clinical features of DLB and PDD. When evaluating the existing management options for Lewy body dementia, it is difficult to fully separate PDD from DLB. However, we have attempted to identify whether the cited studies include patients with PDD and/or DLB. Moreover, we have provided an overview of the current drug pipeline in Lewy body dementia. All currently active trials are in phase I or II and most are focused on disease modification rather than symptomatic treatment. Phase II trial results for neflamapimod show promising results. Due to heterogeneity of symptoms and underlying pathophysiology, there is a need for new biomarker strategies and improved definitions of outcome measures for Lewy body dementia drug trials.

Movement Disorders and the Gut: A Review

There is a close link between multiple movement disorders and gastrointestinal dysfunction. Gastrointestinal symptoms may precede the development of the neurologic syndrome or may arise following the neurologic presentation. This review will provide an overview of gastrointestinal accompaniments to several well-known as well as lesser known movement disorders. It will also highlight several disorders which may not be considered primary movement disorders but have an overlapping presentation of both gastrointestinal and movement abnormalities.

Blood pressure and heart rate responses to orthostatic challenge and Valsalva manoeuvre in mild cognitive impairment with Lewy bodies

OBJECTIVES

Orthostatic hypotension is a common feature of normal ageing, and age-related neurodegenerative diseases, in particular the synucleinopathies including dementia with Lewy bodies. Orthostatic hypotension and other abnormal cardiovascular responses may be early markers of Lewy body disease. We aimed to assess whether abnormal blood pressure and heart rate responses to orthostatic challenge and Valsalva manoeuvre would be more common in mild cognitive impairment with Lewy bodies (MCI-LB) than MCI due to Alzheimer's disease (MCI-AD).

METHODS

MCI patients (n = 89) underwent longitudinal clinical assessment with differential classification of probable MCI-LB, possible MCI-LB, or MCI-AD, with objective autonomic function testing at baseline. Blood pressure and heart rate responses to active stand and Valsalva manoeuvre were calculated from beat-to-beat cardiovascular data, with abnormalities defined by current criteria, and age-adjusted group differences estimated with logistic models.

RESULTS

Orthostatic hypotension and abnormal heart rate response to orthostatic challenge were not more common in probable MCI-LB than MCI-AD. Heart rate abnormalities were likewise not more common in response to Valsalva manoeuvre in probable MCI-LB. An abnormal blood pressure response to Valsalva (delayed return to baseline/absence of overshoot after release of strain) was more common in probable MCI-LB than MCI-AD. In secondary analyses, magnitude of blood pressure drop after active stand and 10-s after release of Valsalva strain were weakly correlated with cardiac sympathetic denervation.

CONCLUSIONS

Probable MCI-LB may feature abnormal blood pressure response to Valsalva, but orthostatic hypotension is not a clear distinguishing feature from MCI-AD.

Heart rate variability in patients with dementia or neurocognitive disorders: A systematic review and meta-analysis

OBJECTIVE

Heart rate variability, a quantitative measure of mainly parasympathetic activity, has been applied in evaluating many types of psychiatric and neurological disorders, including dementia (or neurocognitive disorders). However, although dementia patients often showed significantly lower heart rate variability (various indices) than healthy controls, and different types of dementia had distinct heart rate variability features, the results were not identical across studies. We designed a systematic review and meta-analysis for incorporating data from different studies.

METHODS

We gathered studies comparing heart rate variability in patients with dementia and in healthy controls. Heart rate variability was analysed in several ways: parasympathetic function in hierarchical order (main analysis), total variability, comparison of heart rate variability between different subtypes of dementia, specific indices of heart rate variability and heart rate variability reactivity.

RESULTS

In the initial search, we found 3425 relevant articles, from which 24 studies with a total of 1107 dementia patients and 1017 control participants finally entered the main meta-analysis. The dementia patients had a significantly lower resting heart rate variability for parasympathetic function (Hedges' g = -0.3596, p = 0.0002) and total variability (Hedges' g = -0.3059, p = 0.0002) than the controls. For diagnostic subgroup analysis relative to the controls, heart rate variability was significantly lower in patients with mild cognitive impairment (Hedges' g = -0.3060) and in patients with dementia with Lewy bodies (Hedges' g = -1.4154, p < 0.0001). Relative to patients with Alzheimer's disease, heart rate variability in patients with dementia with Lewy bodies was significantly lower (Hedges' g = -1.5465, p = 0.0381). Meta-regression revealed that gender proportion was significantly associated with effect size.

CONCLUSION

Our results show that dementia patients (especially those with dementia with Lewy bodies and mild cognitive impairment) have lower parasympathetic activity than healthy people. The influence of gender on the results should be carefully interpreted.

Dynamic planar scintigraphy for the rapid kinetic measurement of myocardial 123I-MIBG turnover can identify Lewy body disease

BACKGROUND

Using two static scans for ¹²³I-meta-iodobenzyl-guanidine (¹²³I-MIBG) myocardial scintigraphy ignores the dynamic response from vesicular trapping in nerve terminals. Moreover, the long pause between scans is impractical for patients with Lewy body diseases (LBDs). Here, we optimized indices that capture norepinephrine kinetics, tested their diagnostic performance, and determined the differences in ¹²³I-MIBG performance among disease groups.

METHODS

We developed a new 30-min protocol for ¹²³I-MIBG dynamic planar imaging for suspected LBD patients. Pharmacokinetic modelling of time-activity curves (TACs) was used to calculate three new indices: unidirectional uptake of ¹²³I-MIBG to vesicular trapping (iUp), rate of myocardial ¹²³I-MIBG loss (iLoss), and non-specific fractional distribution of ¹²³I-MIBG in the interstitial space. We compared the performance of the new and existing indices with regard to discrimination of patients with or without LBDs. Subgroup analysis was performed to examine differences in ¹²³I-MIBG turnover between patients in a dementia with Lewy bodies (DLB) group and two Parkinson's disease (PD) groups, one with and the other without REM sleep behaviour disorder (RBD).

RESULTS

iLoss was highly discriminative, particularly for patients with low myocardial ¹²³I-MIBG trapping, and the new indices outperformed existing ones. ROC analysis revealed that the AUC of iLoss (0.903) was significantly higher than that of early HMR (0.863), while comparable to that of delayed HMR (0.892). The RBD-positive PD group and the DLB group had higher turnover rates than the RBD-negative PD group, indicating a potential association between prognosis and iLoss.

CONCLUSION

¹²³I-MIBG turnover can be quantified in 30 min using a three-parameter model based on ¹²³I-MIBG TACs. The discriminatory performance of the new model-based indices might help explain the neurotoxicity or neurodegeneration that occurs in LBD patients.

The role of cardiovascular autonomic failure in the differential diagnosis of α-synucleinopathies

The α-synucleinopathies comprise a group of adult-onset neurodegenerative disorders including Parkinson’s disease (PD), multiple system atrophy (MSA), dementia with Lewy bodies (DLB,) and — as a restricted non-motor form — pure autonomic failure (PAF). Neuropathologically, the α-synucleinopathies are characterized by aggregates of misfolded α-synuclein in the central and peripheral nervous system. Cardiovascular autonomic failure is a common non-motor symptom in people with PD, a key diagnostic criterion in MSA, a supportive feature for the diagnosis of DLB and disease-defining in PAF. The site of autonomic nervous system lesion differs between the α-synucleinopathies, with a predominantly central lesion pattern in MSA versus a peripheral one in PD, DLB, and PAF. In clinical practice, overlapping autonomic features often challenge the differential diagnosis among the α-synucleinopathies, but also distinguish them from related disorders, such as the tauopathies or other neurodegenerative ataxias. In this review, we discuss the differential diagnostic yield of cardiovascular autonomic failure in individuals presenting with isolated autonomic failure, parkinsonism, cognitive impairment, or cerebellar ataxia.

Association of Orthostatic Hypotension With Cerebral Atrophy in Patients With Lewy Body Disorders

OBJECTIVE

To evaluate whether orthostatic hypotension (OH) or supine hypertension (SH) is associated with brain atrophy and white matter hyperintensities (WMH), we analyzed clinical and radiologic data from a large multicenter consortium of patients with Parkinson disease (PD) and dementia with Lewy bodies (DLB).

METHODS

Supine and orthostatic blood pressure (BP) and structural MRI data were extracted from patients with PD and DLB evaluated at 8 tertiary-referral centers in the United States, Canada, Italy, and Japan. OH was defined as a systolic/diastolic BP fall ≥20/10 mm Hg within 3 minutes of standing from the supine position (severe ≥30/15 mm Hg) and SH as a BP ≥140/90 mm Hg with normal sitting BP. Diagnosis-, age-, sex-, and disease duration-adjusted differences in global and regional cerebral atrophy and WMH were appraised with validated semiquantitative rating scales.

RESULTS

A total of 384 patients (310 with PD, 74 with DLB) met eligibility criteria, of whom 44.3% (n = 170) had OH, including 24.7% (n = 42) with severe OH and 41.7% (n = 71) with SH. OH was associated with global brain atrophy (p = 0.004) and regional atrophy involving the anterior-temporal (p = 0.001) and mediotemporal (p = 0.001) regions, greater in severe vs nonsevere OH (p = 0.001). The WMH burden was similar in those with and without OH (p = 0.49). SH was not associated with brain atrophy (p = 0.59) or WMH (p = 0.72).

CONCLUSIONS

OH, but not SH, was associated with cerebral atrophy in Lewy body disorders, with prominent temporal region involvement. Neither OH nor SH was associated with WMH.

Clinico-pathological comparison of patients with autopsy-confirmed Alzheimer's disease, dementia with Lewy bodies, and mixed pathology

INTRODUCTION

Patients with Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) frequently demonstrate coexistent AD neuropathological change (ADNC) and Lewy body pathology (LBP) at autopsy. We investigated the effects of ADNC and LBP on the clinical presentation of these patients.

METHODS

We retrospectively compared clinical and pathological features of patients with different severity of ADNC and LBP. We also compared the burden of medullary LBP between patients with and without autonomic dysfunction.

RESULTS

Compared to pure ADNC, patients with AD/LBP have higher prevalence of DLB symptoms. Autonomic dysfunction strongly predicted the presence of LBP in patients with clinically diagnosed AD, but was not associated with increased LBP burden in the medulla. Severity of ADNC, but not LBP, was associated with cerebral atrophy.

DISCUSSION

Clinical presentation of patients with AD/LBP differs from patients with pure ADNC or LBP. Autonomic dysfunction is a useful marker of otherwise unsuspected LBP.

Neurogenic Orthostatic Hypotension. Lessons From Synucleinopathies

Maintenance of upright blood pressure critically depends on the autonomic nervous system and its failure leads to neurogenic orthostatic hypotension (NOH). The most severe cases are seen in neurodegenerative disorders caused by abnormal α-synuclein deposits: multiple system atrophy (MSA), Parkinson's disease, Lewy body dementia, and pure autonomic failure (PAF). The development of novel treatments for NOH derives from research in these disorders. We provide a brief review of their underlying pathophysiology relevant to understand the rationale behind treatment options for NOH. The goal of treatment is not to normalize blood pressure but rather to improve quality of life and prevent syncope and falls by reducing symptoms of cerebral hypoperfusion. Patients not able to recognize NOH symptoms are at a higher risk for falls. The first step in the management of NOH is to educate patients on how to avoid high-risk situations and providers to identify medications that trigger or worsen NOH. Conservative countermeasures, including diet and compression garments, should always precede pharmacologic therapies. Volume expanders (fludrocortisone and desmopressin) should be used with caution. Drugs that enhance residual sympathetic tone (pyridostigmine and atomoxetine) are more effective in patients with mild disease and in MSA patients with spared postganglionic fibers. Norepinephrine replacement therapy (midodrine and droxidopa) is more effective in patients with neurodegeneration of peripheral noradrenergic fibers like PAF. NOH is often associated with other cardiovascular diseases, most notably supine hypertension, and treatment should be adapted to their presence.

Electrodiagnostic assessment of the autonomic nervous system: A consensus statement endorsed by the American Autonomic Society, American Academy of Neurology, and the International Federation of Clinical Neurophysiology

Evaluation of disorders of the autonomic nervous system is both an art and a science, calling upon the physician's most astute clinical skills as well as knowledge of autonomic neurology and physiology. Over the last three decades, the development of noninvasive clinical tests that assess the function of autonomic nerves, the validation and standardization of these tests, and the growth of a large body of literature characterizing test results in patients with autonomic disorders have equipped clinical practice further with a valuable set of objective tools to assist diagnosis and prognosis. This review, based on current evidence, outlines an international expert consensus set of recommendations to guide clinical electrodiagnostic autonomic testing. Grading and localization of autonomic deficits incorporates scores from sympathetic cardiovascular adrenergic, parasympathetic cardiovagal, and sudomotor testing, as no single test alone is sufficient to diagnose the degree or distribution of autonomic failure. The composite autonomic severity score (CASS) is a useful score of autonomic failure that is normalized for age and gender. Valid indications for autonomic testing include generalized autonomic failure, regional or selective system syndromes of autonomic impairment, peripheral autonomic neuropathy and ganglionopathy, small fiber neuropathy, orthostatic hypotension, orthostatic intolerance, syncope, neurodegenerative disorders, autonomic hyperactivity, and anhidrosis.

Gastrointestinal dysfunction in the synucleinopathies

Interest in gastrointestinal dysfunction in Parkinson's disease has blossomed over the past 30 years and has generated a wealth of investigation into this non-motor aspect of the disorder, research that has encompassed its pathophysiology, its clinical features, and its impact on quality of life. The question of gastrointestinal dysfunction in the other synucleinopathies has not received nearly as much attention, but information and knowledge are growing. In this review, the current knowledge, controversies, and gaps in our understanding of the pathophysiology of gastrointestinal dysfunction in Parkinson's disease and the other synucleinopathies will be addressed, and extended focus will be directed toward the clinical problems involving saliva management, swallowing, gastric emptying, small intestinal function, and bowel function that are so problematic in these disorders.

The Role of Glial Mitochondria in α-Synuclein Toxicity

The abnormal accumulation of alpha-synuclein (α-syn) aggregates in neurons and glial cells is widely known to be associated with many neurodegenerative diseases, including Parkinson’s disease (PD), Dementia with Lewy bodies (DLB), and Multiple system atrophy (MSA). Mitochondrial dysfunction in neurons and glia is known as a key feature of α-syn toxicity. Studies aimed at understanding α-syn-induced toxicity and its role in neurodegenerative diseases have primarily focused on neurons. However, a growing body of evidence demonstrates that glial cells such as microglia and astrocytes have been implicated in the initial pathogenesis and the progression of α-Synucleinopathy. Glial cells are important for supporting neuronal survival, synaptic functions, and local immunity. Furthermore, recent studies highlight the role of mitochondrial metabolism in the normal function of glial cells. In this work, we review the complex relationship between glial mitochondria and α-syn-mediated neurodegeneration, which may provide novel insights into the roles of glial cells in α-syn-associated neurodegenerative diseases.

Cardiovascular Disorders Mediated by Autonomic Nervous System Dysfunction

Cardiovascular disorders, such as orthostatic hypotension and supine hypertension, are common in patients with neurodegenerative synucleinopathies such as Parkinson disease (PD), and may also occur in other conditions, such as peripheral neuropathies, that result in autonomic nervous system (ANS) dysfunction. Dysfunction and degeneration of the ANS are implicated in the development of orthostatic and postprandial hypotension and impaired thermoregulation. Neurogenic orthostatic hypotension (nOH) results from sympathetic failure and is a common autonomic disorder in PD. Supine hypertension may also occur as a result of both sympathetic and parasympathetic dysfunction in conjunction with nOH in the majority of patients with PD. Management of supine hypertension in the setting of nOH can be counterintuitive and challenging. Additionally, the presence of other noncardiovascular comorbidities, such as diabetes mellitus and peripheral edema, may further contribute to the burden of disease. ANS dysfunction thus presents major healthcare implications and challenges for neurology and cardiovascular practices, necessitating an integrated neurology and cardiology management approach.

A research agenda for promoting continence for people living with dementia in the community: Recommendations based on a critical review and expert-by-experience opinion

Aims and objectives

To identify research undertaken in the last decade addressing continence for people living with dementia (PLWD) in the community. To highlight gaps and develop recommendations for future research, taking into account the experiences and priorities of PLWD, caregivers and healthcare professionals.

Methods

A critical review with an Expert Review Group (ERG) comprising researchers, PLWD and facing continence issues, caregivers and other professional stakeholders. Findings are reported in line with the COREQ and Preferred Reporting Items for Systematic reviews and Meta‐Analyses extension for Scoping Reviews checklists.

Background

Caregivers rate the independent use of the toilet as the most important activity for PLWD to retain. However, in 2009 a review identified shortfalls in knowledge and praxis around promoting continence and managing incontinence for PLWD in the community. As absolute numbers of people with dementia are predicted to increase, it is imperative to examine whether these deficits have been addressed.

Results

Of 3,563 records identified, 57 full‐text articles were reviewed. The ERG developed a conceptual model to summarise research evidence according to the extent of the challenge (neuropathology and clinicopathology, prevalence and incidence), gateways to continence services, effectiveness of interventions, outcomes and the potential influences of personal resources, socio‐cultural factors and environmental contexts.

Conclusions

Research on (in)continence for PLWD in the community is under‐developed and has not increased substantially over the last decade. ERG recommendations for future research included user involvement to identify appropriate quality indicators to assess the effectiveness of interventions.

Relevance to clinical practice

There is insufficient evidence on which to base decisions on continence care for PLWD in the community. Omission from continence care guidelines has the effect of marginalising and silencing this population. User involvement in clinical research and developing practice guidelines has the potential for positive systems change.

Orthostatic Hypotension: An Important Risk Factor for Clinical Progression to Mild Cognitive Impairment or Dementia. The Amsterdam Dementia Cohort

Background:

Orthostatic hypotension (OH) has been cross-sectionally and longitudinally related to dementia in the general population. Whether OH contributes to clinical progression to mild cognitive impairment (MCI) or dementia is less certain. Also, differences in risk of progression between patients with early OH (EOH) versus delayed and/or prolonged OH (DPOH) are unclear.

Objective:

Assess the prevalence of EOH and DPOH, investigate the longitudinal association between EOH and DPOH and either incident MCI or dementia.

Methods:

1,882 patients from the Amsterdam Dementia Cohort [64±8 years; 43% female; n = 500 with subjective cognitive decline (SCD), n = 341 MCI, n = 758 Alzheimer’s disease (AD), n = 49 vascular dementia (VaD), n = 146 frontotemporal dementia (FTD), n = 88 Lewy body dementia (DLB)]. Definition OH: systolic blood pressure (BP) drop≥20 mmHg and/or a diastolic BP drop≥10 mmHg at 1 and/or 3 minutes after standing. EOH: OH only at 1 minute, DPOH: OH at (1 and) 3 minutes.

Results:

Prevalence OH: 19% SCD, 28% MCI, 41% dementia. Compared to SCD, odds of having OH were highest in patients with VaD and DLB; ORs (95% CI) were 2.6 (1.4–4.7) and 5.1 (3.1–8.4), respectively. After a mean (SD) follow-up of 2.2 (1.4) years, 105 (22%) of SCD or MCI patients showed clinical progression. Compared to patients without OH, those with DPOH had an increased risk of progression; hazard ratio (95% CI) was 1.7 (1.1–2.7), and those with EOH did not; 0.8 (0.3–1.9).

Conclusion:

Compared to SCD, prevalence of OH was higher in MCI and highest in dementia, particularly in VaD and DLB. DPOH, more likely associated with autonomic dysfunction, is a risk factor for incident MCI or dementia.

Morbidity and mortality in orthostatic hypotension

This review summarizes the current literature on the epidemiology of orthostatic hypotension (OH) in the elderly and in patients with autonomic impairment also known as neurogenic OH (nOH); these two conditions have distinct pathophysiologies and affect different patient populations. The prevalence of OH in the elderly varies depending on the study population. In community dwellers, OH prevalence is estimated at 16%, whereas in institutionalized patients, it may be as high as 60%. The prevalence of OH increases exponentially with age, particularly in those 75 years and older. Multiple epidemiological studies have identified OH as a risk factor for all-cause mortality and cardiovascular disease including heart failure and stroke. Real-world data from administrative databases found polypharmacy, multiple co-morbid conditions, and high health-care utilization as common characteristics in OH patients. A comprehensive evaluation of medications associated with OH is discussed with particular emphasis on the use of anti-hypertensive therapy from two large clinical trials on high-intensive versus standard blood pressure management. Finally, we also review the epidemiology of nOH based on the underlying neurodegenerative disorder (either Parkinson's disease or multiple system atrophy), and the presence of co-morbid conditions such as hypertension and cognitive impairment.

Autonomic Dysfunction in the Synucleinopathies

Autonomic dysfunction is a characteristic feature in the synucleinopathies. Differences in cellular deposition and neuronal populations affected by α-synuclein aggregation influence the manifestations and severity of autonomic failure in the different synucleinopathy disorders. The Lewy body disorders (Parkinson's disease, dementia with Lewy bodies, and pure autonomic failure) have predominantly peripheral involvement, whereas multiple system atrophy chiefly manifests as central autonomic failure. Clinical and laboratory features may be useful in distinguishing the different synucleinopathies based on the pattern and severity of autonomic failure. Treatment recommendations are aimed at the underlying pathophysiology and utilize non-pharmacologic and pharmacologic approaches. This review will focus on pathophysiology, clinical manifestations, and management recommendations for autonomic failure including neurogenic orthostatic hypotension, thermoregulatory dysfunction, genitourinary dysfunction, and gastrointestinal dysfunction in the synucleinopathies.

Accuracy of death certificates for recording parkinsonian syndromes and associated dementia

INTRODUCTION

Death certification is often used to identify patients with certain diseases in epidemiologic research. There have been few studies looking at the accuracy of recording of parkinsonian diagnoses, any associated dementia and the cause of death on death certificates in people with parkinsonian conditions. This study aimed to assess this.

METHODS

Data for these analyses were derived from a prospective incident cohort of degenerative/vascular parkinsonian syndromes with lifelong follow-up from Scotland, UK (the PINE study). In those who died, the available research and clinical care records were reviewed to establish the cause for each patient's death. The sensitivity of death certificates was calculated to detect any parkinsonian diagnosis mentioned on the death certificate, the correct specific diagnosis and the presence of dementia. The causes of death were compared between clinical records and death certificates.

RESULTS

Two hundred and seventy-seven patients had died (180 men), mean age at diagnosis and death 76.9 years and 81.9 years respectively. 66.8% of death certificates mentioned any parkinsonian syndrome but only 49.5% had the correct diagnosis. Sensitivity was highest for Parkinson's disease, those who had parkinsonian-related deaths, had longer disease durations and died out of hospital. Death certificates detected 51.2% of those with dementia. The commonest causes of death were pneumonia, end-stage Parkinsonism and vascular disease with moderate agreement between case-note review and death certification.

CONCLUSION

Deaths certificates often do not mention underlying Parkinsonism or associated dementia and so epidemiological studies should not rely on this as a sole method of identifying cases or studying mortality.

Real-time Positioning Among Nursing Home Residents Living With Dementia: A Case Study

Dementia contributes to the development of pressure injuries (PrIs).

PURPOSE

This study describes the real-time body positions of 2 nursing home (NH) residents, residing in the United States and living with dementia, to inform development of PrI prevention strategies tailored to individual risk profiles.

METHODS

As part of a larger study, eligible residents were fitted with a triaxial accelerometer sensor placed on the anterior chest to monitor body positions 24-hours daily through a 4-week monitoring period. The current study used an observational, prospective design during routine repositioning events for 2 residents. A convenience sample of 2 residents from a single NH wing who were considered moderately at risk for PrI development (Braden Scale score 13-14) with a Brief Interview for Mental Status score in the severely impaired range were selected based on nursing staff recommendation.

RESULTS

Sensor data showed that both residents, although "chairfast" according to the Braden Scale, spent <5% in an upright position and the great majority of time reclining at an angle <50%. One (1) resident demonstrated a persistent side preference.

CONCLUSIONS

Wearable sensors are not a long-term solution for protecting those with dementia from PrI formation but do provide a crude picture of overall body positions throughout the 24-hour day that may inform individualized PrI prevention strategies. Studies including large samples of NH residents living with dementia are warranted.

Altered structure and functional connectivity of the central autonomic network in idiopathic rapid eye movement sleep behaviour disorder

Evidence suggests peripheral autonomic structures may contribute to autonomic dysfunction in idiopathic rapid eye movement sleep behaviour disorder (iRBD). However, whether the central autonomic network (CAN) is affected in iRBD remains unclear. Magnetic resonance imaging data were acquired from 65 participants (32 patients with iRBD and 33 matched healthy controls). We investigated the CAN in patients with iRBD using a combined voxel-based morphometry and resting-state functional connectivity analysis and characterised the relationships between alterations of the CAN and autonomic symptoms. Patients with iRBD had significantly reduced grey matter volume in the brainstem, anterior cingulate and insula compared with healthy controls. Functional connectivity analysis revealed reduced functional connectivity between the brainstem and the cerebellum posterior lobe, temporal lobe and anterior cingulate in patients with iRBD. In patients with iRBD, both reduced grey matter volume and decreased functional connectivity of the CAN were negatively correlated with the Scales for Outcomes in Parkinson's Disease-Autonomic scores. The present study demonstrated that both the structure and the functional connectivity of the CAN were abnormal in patients with iRBD. In addition, correlation analysis suggested that CAN abnormalities may also play a role in the development of autonomic symptoms in iRBD.

Early autonomic and cognitive dysfunction in PD, DLB and MSA: blurring the boundaries between α-synucleinopathies

Differential diagnosis between Parkinson's disease, dementia with Lewy bodies and multiple system atrophy can be difficult, especially because in early phase they might present with overlapping clinical features. Notably, orthostatic hypotension and cognitive dysfunction are common nonmotor aspects of parkinsonian syndromes and can be both present from the earliest stages of all α-synucleinopathies, indicating a common neurobiological basis in their strong relationship. In view of the increasing awareness about the prevalence of mild cognitive dysfunction in multiple system atrophy, the relevance of autonomic dysfunction in demented parkinsonian patients, the critical role of non-motor symptoms in clustering Parkinson's disease patients and the shift to studying patients in the prodromal phase, we will discuss some intrinsic limitations of current clinical diagnostic criteria, even when applied by movement disorder specialists. In particular, we will focus on the early coexistence of autonomic and cognitive dysfunction in the setting of overt or latent parkinsonism as pitfalls in the differential diagnosis of α-synucleinopathies. As early and accurate diagnosis remains of outmost importance for counselling of patients and timely enrolment into disease-modifying clinical trials, a continuous effort of research community is ongoing to further improve the clinical diagnostic accuracy of α-synucleinopathies.

Deaths in dementia: a scoping review of prognostic variables

OBJECTIVES

To identify the types of factors included in research examining mortality in patients with dementia, and to stratify the identified factors by care settings.

DESIGN

We systematically searched PubMed, Embase, PsycINFO and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases, and identified grey literature from the Networked Digital Library of Theses and Dissertations, Open Grey and Grey Literature Report. Two authors independently screened for eligibility of studies. Independent reviewers extracted relevant study information. We conducted a narrative synthesis of the data.

RESULTS

We identified 8254 articles, of which 94 met the inclusion criteria. More than half (n=53) were published between 2009 and 2018 with half from Europe. Studies were conducted across hospices/nursing homes (n=25), hospital (n=23), outpatient clinics (n=21), mixed settings (n=15) and in the community (n=10). Nearly 60% adopted a prospective cohort study design with 87% performing multivariable analysis. Overall, 239 variables were identified and classified into six themes-individual factors, health status, functional ability, cognition and mental health, treatments and health system factors. Although a general set of factors were common across all studies, when stratified by care settings, variations were seen in the specific variables included.

CONCLUSION

Identifying prognostic variables relevant to the dementia population in each setting is key to facilitate appropriate care plans and to ensure timely access to palliative care options. Future research should also focus on ensuring the replicability of prognostic models and to generate a better understanding of the direct and interacting influence of the identified factors on mortality.

Impact of orthostatic hypotension on wheelchair use in patients with Parkinson's disease

Wheelchair use is an important indicator of disease progression in Parkinson's disease (PD). Here, we investigated whether orthostatic hypotension (OH) affects the time to wheelchair use. We examined 33 PD patients with OH and 95 without OH. Median time to start using a wheelchair calculated from the time of disease onset was significantly shorter in patients with OH than in those without OH (12.0 vs 19.0 years; p < 0.001). Thus, appropriate management of OH and motor function is necessary.

Orthostatic hypotension and REM sleep behaviour disorder: impact on clinical outcomes in α-synucleinopathies

OBJECTIVE

Review the effect of orthostatic hypotension (OH) and rapid-eye-movement sleep behavioural disorder (RBD) on survival, cognitive impairment and postural stability, and discuss pathogenic mechanisms involved in the association of these two common non-motor features with relevant clinical outcomes in α-synucleinopathies.

METHODS

We searched PubMed (January 2007-February 2019) for human studies of OH and RBD evaluating cognitive impairment, postural instability, and survival in Parkinson's disease (PD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA) and pure autonomic failure (PAF). Included studies were analysed for design, key results and limitations as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

OH and RBD showed a positive association with cognitive impairment in PD and DLB, conflicting association in PAF, and no association in MSA. OH was correlated with incident falls and postural instability in PD and DLB but not in MSA. The association between RBD and postural instability was inconclusive; positive in five studies, negative in seven. OH, but not RBD, correlated with reduced survival in PD, DLB and MSA. The combination of OH and RBD was associated with cognitive impairment and more rapid progression of postural instability.

CONCLUSIONS

OH and RBD yielded individual and combined negative effects on disability in α-synucleinopathies, reflecting a 'malignant' phenotype of PD with early cognitive impairment and postural instability. Underlying mechanisms may include involvement of selected brainstem cholinergic and noradrenergic nuclei.

Falls in Synucleinopathies

Parkinson's disease (PD) and other synucleinopathies, namely dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), are common degenerative neurological disorders that share synuclein pathology. Although certain cardinal features of parkinsonism, including bradykinesia and rigidity, respond well to levodopa, axial features, such as gait and balance impairment, are less reliably responsive to dopaminergic therapy and surgical interventions. Consequently, falls are common in PD and other synucleinopathies and are a major contributor toward injury and loss of independence. This underscores the need for appropriate fall risk assessment and implementation of preventative measures in all patients with parkinsonism. The aim of this review is therefore to explore modifiable and non-modifiable risk factors for falls in synucleinopathies. We next review and evaluate the evidence for pharmacological, nonpharmacological, and surgical approaches for fall prevention, and emphasize individualized and multifaceted approaches.

Neglected cause of recurrent syncope: a case report of neurogenic orthostatic hypotension

Background

Syncope commonly results in emergency room and physician visits, leading to hospitalization and invasive investigations. Up to 24% of these presentations may be caused by neurogenic orthostatic hypotension (nOH), which continues to be an under-recognized clinical entity. We review an approach to diagnosing nOH.

Case summary

An 85-year-old man with a history of Parkinson’s disease was referred for a history of recurrent syncope, which had resulted in extensive cardiac investigation. Collateral history revealed that the events were orthostatic in nature, but with variable time to onset of symptoms. The patient was found to have significant postural drop in blood pressure without compensatory tachycardia. Cardiovascular autonomic function testing was performed, which confirmed significant autonomic nervous system failure, including a marked hypotensive response on tilt-table testing and a lack of vasoconstriction during Valsalva manoeuvre. The patient was diagnosed with nOH and initiated on midodrine with subjective improvement in the frequency of syncope.

Discussion

Autonomic nervous system failure, with nOH, is a common cause of recurrent syncope, particularly in older patients. Attention to detail during the medical history, including precipitating factors and the presence of prodromal symptoms prior to syncope, is critical for making the correct diagnosis. Measuring orthostatic vital signs correctly in patients with syncope provides valuable information, is cost-effective, and critical to diagnose nOH.

Review: Clinical, neuropathological and genetic features of Lewy body dementias

Lewy body dementias are the second most common neurodegenerative dementias after Alzheimer's disease and include dementia with Lewy bodies and Parkinson's disease dementia. They share similar clinical and neuropathological features but differ in the time of dementia and parkinsonism onset. Although Lewy bodies are their main pathological hallmark, several studies have shown the emerging importance of Alzheimer's disease pathology. Clinical amyloid-β imaging using Pittsburgh Compound B (PiB) supports neuropathological studies which found that amyloid-β pathology is more common in dementia with Lewy bodies than in Parkinson's disease dementia. Nevertheless, other co-occurring pathologies, such as cerebral amyloid angiopathy, TDP-43 pathology and synaptic pathology may also influence the development of neurodegeneration and dementia. Recent genetic studies demonstrated an important role of APOE genotype and other genes such as GBA and SNCA which seem to be involved in the pathophysiology of Lewy body dementias. The aim of this article is to review the main clinical, neuropathological and genetic aspects of dementia with Lewy bodies and Parkinson's disease dementia. This is particularly relevant as future management for these two conditions may differ.

Association of autonomic symptoms with disease progression and survival in progressive supranuclear palsy

BACKGROUND

Development of autonomic failure is associated with more rapid disease course and shorter survival in patients with Parkinson's disease and multiple system atrophy. However, autonomic symptoms have not been specifically assessed as a prognostic factor in progressive supranuclear palsy (PSP). We evaluated whether development of autonomic symptoms is associated with disease progression and survival in PSP.

METHODS

A retrospective review of clinical data from consecutive patients with autopsy-confirmed PSP from the Queen Square Brain Bank between January 2012 and November 2016 was performed. Time from disease onset to four autonomic symptoms (constipation, urinary symptoms, erectile dysfunction and orthostatic hypotension) were noted. Time from diagnosis to five disease milestones and survival were calculated to assess disease progression, and their risk was estimated through a Cox proportional hazards model.

RESULTS

A total of 103 PSP patients were included. Urinary symptoms and constipation were present in 81% and 71% of cases, respectively. Early development of constipation and urinary symptoms were associated with higher risk of reaching the first disease milestone (respectively, HR: 0.88; 95% CI 0.83 to 0.92; p<0.001; and HR: 0.80; 95% CI 0.75 to 0.86; p<0.001) and with a shorter survival in these patients (respectively, HR: 0.73; 95% CI 0.64 to 0.84; p<0.001; and HR: 0.88; 95% CI 0.80 to 0.96; p=0.004). On multivariate analysis, Richardson syndrome phenotype was the other variable independently associated with shorter survival.

CONCLUSIONS

Earlier urinary symptoms and constipation are associated with a more rapid disease progression and reduced survival in patients with PSP.

Autonomic Dysfunction in α-Synucleinopathies

The α-synucleinopathies are a group of neurodegenerative diseases characterized by abnormal accumulation of insoluble α-synuclein in neurons and glial cells, comprising Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). Although varying in prevalence, symptom patterns, and severity among disorders, all α-synucleinopathies have in common autonomic nervous system dysfunctions, which reduce quality of life. Frequent symptoms among α-synucleinopathies include constipation, urinary and sexual dysfunction, and cardiovascular autonomic symptoms such as orthostatic hypotension, supine hypertension, and reduced heart rate variability. Symptoms due to autonomic dysfunction can appear before motor symptom onset, particularly in MSA and PD, hence, detection and quantitative analysis of these symptoms can enable early diagnosis and initiation of treatment, as well as identification of at-risk populations. While patients with PD, DLB, and MSA show both central and peripheral nervous system involvement of α-synuclein pathology, pure autonomic failure (PAF) is a condition characterized by generalized dysregulation of the autonomic nervous system with neuronal cytoplasmic α-synuclein inclusions in the peripheral autonomic small nerve fibers. Patients with PAF often present with orthostatic hypotension, reduced heart rate variability, anhydrosis, erectile dysfunction, and constipation, without motor or cognitive impairment. These patients also have an increased risk of developing an α-synucleinopathy with central involvement, such as PD, DLB, or MSA in later life, possibly indicating a pathophysiological disease continuum. Pathophysiological aspects, as well as developments in diagnosing and treating dysautonomic symptoms in patients with α-synucleinopathies are discussed in this review.

Survival time and differences between dementia with Lewy bodies and Alzheimer's disease following diagnosis: A meta-analysis of longitudinal studies

OBJECTIVE

To synthesize the evidence across longitudinal studies comparing survival in dementia with Lewy bodies (DLB) and Alzheimer's disease (AD).

METHODS

We conducted a systematic review and meta-analysis of studies comparing survival in clinically diagnosed DLB to AD. Longitudinal cohort studies were identified through a systematic search of major electronic databases from inception to May 2018. A random effects meta-analysis was performed to calculate survival time and relative risk of death.

RESULTS

Overall, 11 studies were identified including 22,952 patients with dementia: 2029 with DLB (mean diagnosis age 76.3; 47% female) compared with 20,923 with AD (mean diagnosis age 77.2; 65.1% female). Average survival time in DLB from diagnosis was 4.11 years (SD ± 4.10) and in AD 5.66 (SD ± 5.32) years, equating to a 1.60 (95% CI: -2.44 to -0.77) years shorter survival in DLB (p < 0.01). Relative risk of death was increased by 1.35 (95%CI: 1.17-1.55) in DLB compared to AD (p < 0.01). Differences in survival were not explained by follow-up time, age at diagnosis, gender, or cognitive score.

CONCLUSIONS

There is consistent evidence for higher and earlier mortality in DLB compared to AD. This is important for all stakeholders and underlines the importance of expanding research into DLB.

Orthostatic hypotension and dementia incidence: links and implications

Orthostatic hypotension (OH) is a common condition, particularly in patients with α-synucleinopathies such as Parkinson's disease, and has a significant impact on activities of daily living and quality of life. Recent data suggest an association with cognitive impairment. Herein, we review the evidence that OH increases the odds of incident mild cognitive impairment and dementia. Potential mechanisms underlying the putative relationship are discussed, including cerebral hypoperfusion, supine hypertension, white matter hyperintensities, and neurodegeneration. Finally, we highlight the challenges with respect to treatment and the negative impact on the quality of life and long-term prognosis presented by the coexistence of OH and dementia. Large population-based studies have reported that OH is associated with about a 20% increased risk of dementia in the general population, while smaller cohort studies suggest an even greater effect in patients with α-synucleinopathies (3- to 7-fold higher than controls). Ultimately, OH exposure is difficult to quantify, predominantly limited to pressure regulation during a one-time orthostatic challenge, and the causative association with dementia may turn out to be bidirectional, especially in α-synucleinopathies. Early diagnosis and treatment of OH may improve long-term prognosis.