Epidemiology, Diagnosis, and Management of Neurogenic Orthostatic Hypotension

Epidemiology and Risk Factors for Orthostatic Hypotension and Its Severity in Residents Aged > 60 years: A Cross-Sectional Study

This cross-sectional study investigated the epidemiology and risk factors associated with orthostatic hypotension (OH) and its severity in older adults residing in the Jizhou community of Tianjin and the Jimei community of Xiamen. The study, conducted from March to September 2019, involved adults aged over 60. A comprehensive questionnaire survey was administered, resulting in the enrolment of 4383 older adults. The overall prevalence of OH was found to be 11.7% (516 out of 4383). Notably, a significant gender difference was observed, with a prevalence of 10% among males (194 out of 1926) and 13.1% among females (322 out of 2457) (P=0.002). Among individuals with OH, 332 exhibited mild symptoms, 64 had moderate OH, 58 had severe OH cases, and 50 have very severe OH. Multivariable logistic regression analysis revealed that being female, widowed, engaging in general social activities, and a history of hypertension, migraines, heart disease, cerebrovascular disease, and mental health conditions (anxiety and depression) were independently associated with OH. Ordinal logistic regression analysis further confirmed that hypertension, migraine, and a history of general anesthesia surgery were independently associated with the severity of OH. This study highlights a relatively high prevalence of OH among older adults in the Jizhou community of Tianjin and the Jimei community of Xiamen, China. The identified risk factors, particularly social activities, and hypertension, significantly influence the severity of OH. Further examination is required to corroborate these findings and investigate potential interventions.

A retrospective analysis of neurogenic orthostatic hypotension in long-term care facility residents with recurrent falls

INTRODUCTION

Approximately 50 % of residents in long-term care facilities fall yearly and orthostatic hypotension accounts for a significant portion of them. Neurogenic orthostatic hypotension - a subtype of orthostatic hypotension - is important to be recognized as its management is far more complex; undertreatment of these older adults can lead to recurrent falls, high healthcare cost burden, and increased morbidity and mortality. The primary purpose of our study was to describe the rate of neurogenic orthostatic hypotension in older adults in a long-term care facility, with a secondary purpose to describe risk factors for neurogenic orthostatic hypotension in this population.

METHODS

We conducted a retrospective case-control study of residents with recurrent falls at the Dayton Veteran's Affairs long-term care facility. Charts were manually reviewed. Inclusion criterion was three or more falls and age 65 or greater; we did not have exclusion criteria. ICD10 codes and most recent primary care physician notes were used to identify comorbidity diagnoses. Recent orthostatic vitals were used to assess orthostatic hypotension or neurogenic orthostatic hypotension diagnoses.

RESULTS

Of our sample of 224 residents, we observed a prevalence of 20.5 % for neurogenic orthostatic hypotension and 32.1 % for orthostatic hypotension. Neither of them had diagnosis of neurogenic orthostatic hypotension documented. Parkinson's disease was associated with neurogenic orthostatic hypotension (OR-4.3; p = 0.002). Hypertension was prevalent in 69.6 % of residents with orthostatic vitals suggestive of neurogenic orthostatic hypotension.

CONCLUSION

Older adults with recurrent falls at a long-term care facility meet criteria for neurogenic orthostatic hypotension diagnosis far more often than is documented. Common comorbidities associated with neurogenic orthostatic hypotension in this population include Parkinson's disease.

Droxidopa or Atomoxetine for Refractory Hypotension in Critically Ill Cardiothoracic Surgery Patients

OBJECTIVE

To evaluate the effects of droxidopa or atomoxetine on intravenous (IV) vasoactive agent discontinuation in cardiothoracic intensive care unit (ICU) patients with hypotension refractory to midodrine.

DESIGN

Single-center, retrospective cohort study.

SETTING

Tertiary- and quaternary-care university teaching hospital.

PARTICIPANTS

Included patients who received at least 4 consecutive doses of droxidopa or atomoxetine and remained on concurrent midodrine. Patients were excluded if they received study medication before admission, had clinical deterioration after study medication initiation requiring additional vasoactives/escalation of IV vasoactive dosage for at least 12 hours, had a diagnosis of hepatorenal syndrome, were prisoners, or were pregnant.

INTERVENTIONS

Droxidopa, atomoxetine, or both.

MEASUREMENTS AND MAIN RESULTS

The primary endpoint was time to discontinuation of IV vasoactive agents after initiation of study medication, analyzed using a Kaplan-Meier estimate with the Wilcoxon method, censoring death within 24 hours of the last dose of study medication. No adjustment for repetitive analyses was made, as the analysis was hypothesis-generating. Of the 72 charts reviewed, 45 patients met inclusion criteria (18 atomoxetine, 17 droxidopa, and 10 both). There were no differences in median time to discontinuation of IV vasoactive agents (21.9 days v 8.0 days v 13.9 days, respectively; p = 0.259) or ICU or hospital length of stay between groups. A higher percentage of patients who survived to hospital discharge received both study medications or droxidopa alone (90% v 76.5%) than atomoxetine alone (44.4%, p = 0.028).

CONCLUSIONS

Droxidopa and atomoxetine are oral vasoactive agents with potential mechanisms to facilitate IV vasopressor weaning for patients in the ICU with hypotension refractory to midodrine, but further prospective research is needed.

Frequency of Orthostatic Hypotension in Isolated REM Sleep Behavior Disorder

BACKGROUND AND OBJECTIVES

Although orthostatic hypotension (OH) can be an early feature of autonomic dysfunction in isolated REM sleep behavior disorder (iRBD), no large-scale studies have examined the frequency of OH in iRBD. In this study, we prospectively evaluated the frequency of OH in a large multicenter iRBD cohort.

METHODS

Participants 18 years or older with video polysomnogram-confirmed iRBD were enrolled through the North American Prodromal Synucleinopathy consortium. All participants underwent 3-minute orthostatic stand testing to assess the frequency of OH, and a Δ heart rate/Δ systolic blood pressure (ΔHR/ΔSBP) ratio <0.5 was used to define reduced HR augmentation, suggestive of neurogenic OH. All participants completed a battery of assessments, including the Scales for Outcomes in Parkinson Disease-Autonomic Dysfunction (SCOPA-AUT) and others assessing cognitive, motor, psychiatric, and sensory domains.

RESULTS

Of 340 iRBD participants (65 ± 10 years, 82% male), 93 (27%) met criteria for OH (ΔHR/ΔSBP 0.37 ± 0.28; range 0.0-1.57), and of these, 72 (77%) met criteria for OH with reduced HR augmentation (ΔHR/ΔSBP 0.28 ± 0.21; range 0.0-0.5). Supine hypertension (sHTN) was present in 72% of those with OH. Compared with iRBD participants without OH, those with OH were older, reported older age of RBD symptom onset, and had worse olfaction. There was no difference in autonomic symptom scores as measured by SCOPA-AUT.

DISCUSSION

OH and sHTN are common in iRBD. However, as patients may have reduced autonomic symptom awareness, orthostatic stand testing should be considered in clinical evaluations. Longitudinal studies are needed to clarify the relationship between OH and phenoconversion risk in iRBD.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov: NCT03623672; North American Prodromal Synucleinopathy Consortium.

Interactive effect of orthostatic hypotension on gray matter atrophy associated with hyposmia and RBD in de novo Parkinson's disease

BACKGROUND

Orthostatic hypotension (OH) is a potential modifiable risk factor for cognitive impairment in patients with Parkinson's disease (PD). Although other risk factors for dementia, hyposmia and REM sleep behavior disorder (RBD), are closely associated with autonomic dysfunction in PD, little is known about how these risk factors influence cognitive function and cerebral pathology.

OBJECTIVE

We investigated how these three factors contribute to gray matter atrophy by considering the interaction of OH with hyposmia and RBD.

METHODS

We analyzed cortical thickness, subcortical gray matter volume, and cognitive measures from 78 patients with de novo PD who underwent the head-up tilt test for the diagnosis of OH.

RESULTS

Whole-brain analyses with Monte Carlo corrections revealed that hyposmia was associated with decreased cortical thickness in a marginal branch of the cingulate sulcus among patients with OH, and cortical thickness in this area correlated with cognitive functioning only in patients with OH. Subcortical gray matter volume analysis indicated that severe RBD was associated with decreased volume in the left hippocampus and bilateral amygdala among patients with OH.

CONCLUSION

Even in early PD, OH exerts effects on gray matter atrophy and cognitive dysfunction by interacting with RBD and hyposmia. OH might exacerbate cerebral pathology induced by hyposmia or RBD.

Non-pharmacological and drug treatment of autonomic dysfunction in multiple system atrophy: current status and future directions

Multiple system atrophy (MSA) is a sporadic, fatal, and rapidly progressive neurodegenerative disease of unknown etiology that is clinically characterized by autonomic failure, parkinsonism, cerebellar ataxia, and pyramidal signs in any combination. Early onset and extensive autonomic dysfunction, including cardiovascular dysfunction characterized by orthostatic hypotension (OH) and supine hypertension, urinary dysfunction characterized by overactive bladder and incomplete bladder emptying, sexual dysfunction characterized by sexual desire deficiency and erectile dysfunction, and gastrointestinal dysfunction characterized by delayed gastric emptying and constipation, are the main features of MSA. Autonomic dysfunction greatly reduces quality of life and increases mortality. Therefore, early diagnosis and intervention are urgently needed to benefit MSA patients. In this review, we aim to discuss the systematic treatment of autonomic dysfunction in MSA, and focus on the current methods, starting from non-pharmacological methods, such as patient education, psychotherapy, diet change, surgery, and neuromodulation, to various drug treatments targeting autonomic nerve and its projection fibers. In addition, we also draw attention to the interactions among various treatments, and introduce novel methods proposed in recent years, such as gene therapy, stem cell therapy, and neural prosthesis implantation. Furthermore, we elaborate on the specific targets and mechanisms of action of various drugs. We would like to call for large-scale research to determine the efficacy of these methods in the future. Finally, we point out that studies on the pathogenesis of MSA and pathophysiological mechanisms of various autonomic dysfunction would also contribute to the development of new promising treatments and concepts.

Non-Pharmacological Treatment of Autonomic Dysfunction in Parkinson's Disease and Other Synucleinopathies

Symptoms of autonomic dysfunction are prevalent and can be very debilitating, reducing the quality of life in patients with Parkinson's disease (PD) and other synucleinopathies such as dementia with Lewy bodies and multiple system atrophy. Non-pharmacological therapies are key to effective management and are frequently used alone in patients with mild autonomic symptoms, or in combination with pharmacological therapies in patients with moderate and severe symptoms. This article focuses on non-pharmacological approaches. Our objective was to review the non-drug and non-surgical approaches to treating autonomic symptoms in patients with PD and other synucleinopathies, focusing on cardiovascular, gastrointestinal, and genitourinary autonomic dysfunction. Evidence supporting the effectiveness of non-pharmacological treatment for the management of neurogenic orthostatic hypotension, supine hypertension, constipation, and bladder and sexual dysfunction is available. High-quality prospective trials are scarce, yet some non-pharmacological interventions (e.g., physical counter maneuvers) can be evaluated relatively quickly on an individual basis and often seem effective. The emerging variety of clinical presentations advocates for a stepwise, individualized, and non-pharmacological approach for the management of autonomic symptoms. Often, the first step is to reduce or discontinue drugs that cause or aggravate autonomic symptoms followed by lifestyle measures. While non-pharmacological and non-surgical treatments are available and, in many cases, effective to improve symptoms of autonomic dysfunction in PD and other synucleinopathies, they are often overlooked. Large randomized trials testing and comparing non-pharmacological approaches are warranted.

At-Home Blood Pressure Measurements Provide Better Assessments of Orthostatic Hypotension in Parkinson's Disease

Orthostatic hypotension (OH) is common in Parkinson's Disease (PD). It is intermittent, exacerbated by stressors including meals, medications, and dehydration, and frequently is unrecognized. Although intermittent, assessment is usually by a single "in clinic" BP measurement. This study examines whether 10 home measurements are more sensitive in detecting OH than a single "in clinic" measurement. Participants (44 people with PD and 16 controls) were instructed to measure lying and standing BP at home. BP was measured on five consecutive days upon waking and before bedtime. Symptoms were also assessed using the Movement Disorder Society United Parkinson's Disease Rating Scale and the Non-Motor Questionnaire. While a postural drop in systolic BP (≥20 mmHg) was recorded "in clinic" in thirteen of the forty-four PD participants, a postural drop was found in at least one of the ten home measurements in twenty-eight of the forty-four participants. Morning hypertension and variability in lying systolic BP was more common in these subjects than in those without a postural drop or the controls. A greater number of measurements of lying and standing BP are more likely to reveal orthostatic hypotension, variation in systolic BP, and hypertension than a single office measurement in people with PD.

The Impact of Head-Up Tilt Sleeping on Orthostatic Tolerance: A Scoping Review

To systematically summarize the evidence of head-up tilt sleeping (HUTS) on orthostatic tolerance, we conducted a systematic, predefined search in PubMed, OVID Embase, Cochrane and Web of Science. We included studies assessing the effect of HUTS on orthostatic tolerance and other cardiovascular measures and rated the quality with the American Academy of Neurology risk of bias tool. We included 10 studies (n = 185) in four groups: orthostatic hypotension (OH; 6 studies, n = 103), vasovagal syncope (1 study, n = 12), nocturnal angina pectoris (1 study, n = 10) and healthy subjects (2 studies, n = 58). HUTS duration varied (1 day-4 months) with variable inclinations (5°-15°). In two of six OH studies, HUTS significantly improved standing systolic blood pressure. Orthostatic tolerance was consistently enhanced in OH studies with higher angles (≥12°), in 2 out of 3 with smaller angles (5°) but also in one studying horizontal sleeping. In vasovagal syncope, HUTS significantly augmented resilience to extreme orthostatic stress. One study was rated as a class II risk of bias, one of Class II/III and eight of Class IV. The evidence favouring HUTS to improve orthostatic tolerance is weak due to variable interventions, populations, small samples and a high risk of bias. Despite this, we found some physiological signs suggesting a beneficial effect.

Orthostatic Hypotension in Benign Prostatic Hyperplasia Patients and Its Association With Alpha-1 Antagonist Use: A Comprehensive Literature Review

Orthostatic hypotension (OH) is frequently observed in benign prostatic hyperplasia (BPH) patients undergoing alpha-1 adrenergic antagonist (A1AA) therapy. While previous studies have acknowledged the prevalence of OH in BPH patients on A1AAs, limited data exist on ranking the safety of different A1AAs. This comprehensive review explores the underlying mechanisms of OH, examines numerous factors influencing its development, and provides insights into effective treatment strategies such as hydration, gradual postural changes, leg exercises, compression stockings, and tilt-table training for BPH management. The review highlights the significance of individualized care, interdisciplinary collaboration, and further research to optimize A1AA treatment, improve patient outcomes, and enhance quality of life.

Ampreloxetine Versus Droxidopa in Neurogenic Orthostatic Hypotension: A Comparative Review

Neurogenic orthostatic hypotension (nOH) is a disabling problem of autonomic dysfunction in patients with Parkinson's disease, which is associated with poor quality of life and higher mortality rates. The purpose of this literature review was to explore and compare the efficacy and safety of droxidopa (an existing treatment) and ampreloxetine (a newer medication) in the treatment of nOH. We used a mixed-method literature review that addresses the epidemiology, pathophysiology, and pharmacological and non-pharmacological management of nOH in Parkinson's disease in a general way, with a more exploratory approach to droxidopa- and ampreloxetine-controlled trial studies. We included a total of 10 studies of randomized controlled trials with eight studies focused on droxidopa and two studies focused on ampreloxetine. These two drugs were analyzed and compared based on the collected individual study results. Treatment of nOH in Parkinson's disease patients with droxidopa or ampreloxetine showed clinically meaningful and statistically significant improvements relative to placebo on the components of the OHSA (Orthostatic Hypotension Symptom Assessment) composite score and OHDAS (Orthostatic Hypotension Daily Activity Scale composite scores) composite score. Droxidopa had an improved effect on daily activities, with an associated increase in standing systolic blood pressure (BP), but the long-term efficacy of droxidopa has not been documented. Standing systolic BP was maintained by ampreloxetine and worsened after the withdrawal phase. This highlights the importance of conducting further research which will help us to improve the therapeutic approach for patients with nOH and Parkinson's disease.

Parkinson's disease and cardiovascular involvement: Edifying insights (Review)

Parkinson's disease (PD) is one of the most common neurodegenerative illnesses, and is a major healthcare burden with prodigious consequences on life-quality, morbidity, and survival. Cardiovascular diseases are the leading cause of mortality worldwide and growing evidence frequently reports their co-existence with PD. Cardiac dysautonomia due to autonomic nervous system malfunction is the most prevalent type of cardiovascular manifestation in these patients, comprising orthostatic and postprandial hypotension, along with supine and postural hypertension. Moreover, many studies have endorsed the risk of patients with PD to develop ischemic heart disease, heart failure and even arrhythmias, but the underlying mechanisms are not entirely clear. As importantly, the medication used in treating PD, such as levodopa, dopamine agonists or anticholinergic agents, is also responsible for cardiovascular adverse reactions, but further studies are required to elucidate the underlying mechanisms. The purpose of this review was to provide a comprehensive overview of current available data regarding the overlapping cardiovascular disease in patients with PD.

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.

Diagnosis and treatment of orthostatic hypotension

Orthostatic hypotension is an unusually large decrease in blood pressure on standing that increases the risk of adverse outcomes even when asymptomatic. Improvements in haemodynamic profiling with continuous blood pressure measurements have uncovered four major subtypes: initial orthostatic hypotension, delayed blood pressure recovery, classic orthostatic hypotension, and delayed orthostatic hypotension. Clinical presentations are varied and range from cognitive slowing with hypotensive unawareness or unexplained falls to classic presyncope and syncope. Establishing whether symptoms are due to orthostatic hypotension requires careful history taking, a thorough physical examination, and supine and upright blood pressure measurements. Management and prognosis vary according to the underlying cause, with the main distinction being whether orthostatic hypotension is neurogenic or non-neurogenic. Neurogenic orthostatic hypotension might be the earliest clinical manifestation of Parkinson's disease or related synucleinopathies, and often coincides with supine hypertension. The emerging variety of clinical presentations advocates a stepwise, individualised, and primarily non-pharmacological approach to the management of orthostatic hypotension. Such an approach could include the cessation of blood pressure lowering drugs, adoption of lifestyle measures (eg, counterpressure manoeuvres), and treatment with pharmacological agents in selected cases.

Cardiovascular/Stroke Risk Stratification in Parkinson's Disease Patients Using Atherosclerosis Pathway and Artificial Intelligence Paradigm: A Systematic Review

Parkinson’s disease (PD) is a severe, incurable, and costly condition leading to heart failure. The link between PD and cardiovascular disease (CVD) is not available, leading to controversies and poor prognosis. Artificial Intelligence (AI) has already shown promise for CVD/stroke risk stratification. However, due to a lack of sample size, comorbidity, insufficient validation, clinical examination, and a lack of big data configuration, there have been no well-explained bias-free AI investigations to establish the CVD/Stroke risk stratification in the PD framework. The study has two objectives: (i) to establish a solid link between PD and CVD/stroke; and (ii) to use the AI paradigm to examine a well-defined CVD/stroke risk stratification in the PD framework. The PRISMA search strategy selected 223 studies for CVD/stroke risk, of which 54 and 44 studies were related to the link between PD-CVD, and PD-stroke, respectively, 59 studies for joint PD-CVD-Stroke framework, and 66 studies were only for the early PD diagnosis without CVD/stroke link. Sequential biological links were used for establishing the hypothesis. For AI design, PD risk factors as covariates along with CVD/stroke as the gold standard were used for predicting the CVD/stroke risk. The most fundamental cause of CVD/stroke damage due to PD is cardiac autonomic dysfunction due to neurodegeneration that leads to heart failure and its edema, and this validated our hypothesis. Finally, we present the novel AI solutions for CVD/stroke risk prediction in the PD framework. The study also recommends strategies for removing the bias in AI for CVD/stroke risk prediction using the PD framework.

Fatigue in Patients With Multiple System Atrophy: A Prospective Cohort Study

BACKGROUND AND OBJECTIVES

Non-motor symptoms are common in patients with multiple system atrophy (MSA), but there is limited knowledge regarding fatigue in MSA. This study aimed to investigate the frequency and evolution of fatigue and the factors related to fatigue and its progression in patients with MSA at an early stage.

METHODS

Patients with probable MSA were comprehensively evaluated at both baseline and the 1-year follow-up, including their motor and non-motor symptoms. Fatigue and anxiety were assessed using the fatigue severity scale (FSS) and Hamilton anxiety rating scale (HARS), respectively. Orthostatic hypotension (OH) was defined as a decrease in the systolic and/or diastolic blood pressure by at least 30 mmHg and 15 mmHg, respectively. The binary logistic regression model and linear regression model were used to analyze the factors related to fatigue and its progression, respectively.

RESULTS

This study enrolled 146 patients with MSA. The frequency of fatigue was 60.3%, 55.1%, and 64.9% in MSA, MSA with predominant parkinsonism (MSA-P), and MSA with predominant cerebellar ataxia (MSA-C), respectively. The frequency of fatigue and the FSS score in MSA patients increased from baseline to the 1-year follow-up (P < 0.05). Young age (OR 0.939, 95% CI 0.894-0.987), OH (OR 2.806, 95% CI 1.253-6.286), and high HARS score (OR 1.014, 95% CI 1.035-1.177) were associated with fatigue in MSA. OH was associated with fatigue in MSA-P (OR 3.391, 95% CI 1.066-10.788), while high HARS score was associated with fatigue in MSA-C (OR 1.159, 95% CI 1.043-1.287). Additionally, only low FSS scores at baseline were associated with the annual progression rate of FSS scores in MSA, MSA-P, and MSA-C (P<0.05). Neurofilament light chain, α-synuclein, glial fibrillary acidic protein, brain-derived neurotrophic factor, and triggering receptor expressed on myeloid cell-2 were not significantly associated with fatigue and its progression in MSA.

CONCLUSION

Fatigue was prevalent in early-stage MSA, and it increased and remained persistent over time. This study demonstrated that OH and anxiety were associated with fatigue in MSA patients.

Pharmacokinetics and pharmacodynamics of ampreloxetine, a novel, selective norepinephrine reuptake inhibitor, in symptomatic neurogenic orthostatic hypotension

Purpose

Ampreloxetine is a novel, selective, long-acting norepinephrine reuptake (NET) inhibitor being investigated as a once-daily oral treatment for symptomatic neurogenic orthostatic hypotension (nOH) in patients with autonomic synucleinopathies. The purpose of this study was to characterize the pharmacokinetic and pharmacodynamic profiles of ampreloxetine in this target population.

Methods

Patients with nOH were enrolled in a multicenter, phase II clinical trial of ampreloxetine (NCT02705755). They received escalating doses over 5 days in the clinical research unit, followed by 20 weeks of open-label treatment and then a 4-week withdrawal. As neurochemical biomarkers of NET inhibition, we assayed plasma concentrations of norepinephrine (NE) and its main intraneuronal metabolite 3,4-dihydroxyphenylglycol (DHPG) pre- and post-ampreloxetine.

Results

Thirty-four patients with nOH were enrolled. Plasma ampreloxetine concentrations increased with repeated escalating doses, with peak concentrations observed 6–9 h post-drug administration. The median ampreloxetine dose in the 20-week treatment phase was 10 mg once daily. Plasma ampreloxetine concentrations reached steady state by 2 weeks, with stable plasma levels over 24 h. No influence of age or renal function on ampreloxetine plasma concentrations was observed. On treatment, compared to baseline, plasma NE significantly increased by 71% (p < 0.005), plasma DHPG significantly declined by 22% (p < 0.05), and the NE:DHPG ratio significantly increased (p < 0.001).

Conclusions

Persistent elevation of plasma NE levels accompanied by reduced DHPG levels after ampreloxetine suggests reduced neuronal reuptake and metabolism of NE in postganglionic efferent sympathetic neurons. The findings are consistent with long-lasting NET inhibition, which may increase vasoconstrictor tone, supporting once-daily ampreloxetine dosing in patients with nOH.

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.

Management Strategies for Comorbid Supine Hypertension in Patients with Neurogenic Orthostatic Hypotension

PURPOSE OF REVIEW

In autonomic failure, neurogenic orthostatic hypotension (nOH) and neurogenic supine hypertension (nSH) are interrelated conditions characterized by postural blood pressure (BP) dysregulation. nOH results in a sustained BP drop upon standing, which can lead to symptoms that include lightheadedness, orthostatic dizziness, presyncope, and syncope. nSH is characterized by elevated BP when supine and, although often asymptomatic, may increase long-term cardiovascular and cerebrovascular risk. This article reviews the pathophysiology and clinical characteristics of nOH and nSH, and describes the management of patients with both nOH and nSH.

RECENT FINDINGS

Pressor medications required to treat the symptoms of nOH also increase the risk of nSH. Because nOH and nSH are hemodynamically opposed, therapies to treat one condition may exacerbate the other. The management of patients with nOH who also have nSH can be challenging and requires an individualized approach to balance the short- and long-term risks associated with these conditions. Approaches to manage neurogenic BP dysregulation include nonpharmacologic approaches and pharmacologic treatments. A stepwise treatment approach is presented to help guide neurologists in managing patients with both nOH and nSH.

Management of Orthostatic Hypotension

PURPOSE OF REVIEW

This article reviews the management of orthostatic hypotension with emphasis on neurogenic orthostatic hypotension.

RECENT FINDINGS

Establishing whether the cause of orthostatic hypotension is a pathologic lesion in sympathetic neurons (ie, neurogenic orthostatic hypotension) or secondary to other medical causes (ie, non-neurogenic orthostatic hypotension) can be achieved by measuring blood pressure and heart rate at the bedside. Whereas fludrocortisone has been extensively used as first-line treatment in the past, it is associated with adverse events including renal and cardiac failure and increased risk of all-cause hospitalization. Distinguishing whether neurogenic orthostatic hypotension is caused by central or peripheral dysfunction has therapeutic implications. Patients with peripheral sympathetic denervation respond better to norepinephrine agonists/precursors such as droxidopa, whereas patients with central autonomic dysfunction respond better to norepinephrine reuptake inhibitors.

SUMMARY

Management of orthostatic hypotension is aimed at improving quality of life and reducing symptoms rather than at normalizing blood pressure. Nonpharmacologic measures are the key to success. Pharmacologic options include volume expansion with fludrocortisone and sympathetic enhancement with midodrine, droxidopa, and norepinephrine reuptake inhibitors. Neurogenic supine hypertension complicates management of orthostatic hypotension and is primarily ameliorated by avoiding the supine position and sleeping with the head of the bed elevated.

Clinical Trials for Neurogenic Orthostatic Hypotension: A Comprehensive Review of Endpoints, Pitfalls, and Challenges

Neurogenic orthostatic hypotension (nOH) is among the most debilitating nonmotor features of patients with Parkinson's disease (PD) and other synucleinopathies. Patients with PD and nOH generate more hospitalizations, make more emergency room visits, create more telephone calls/mails to doctors, and have earlier mortality than those with PD but without nOH. Overall, the health-related cost in patients with PD and OH is 2.5-fold higher compared with patients with PD without OH. Hence, developing effective therapies for nOH should be a research priority. In the last few decades, improved understanding of the pathophysiology of nOH has led to the identification of therapeutic targets and the development and approval of two drugs, midodrine and droxidopa. More effective and safer therapies, however, are still needed, particularly agents that could selectively increase blood pressure only in the standing position because supine hypertension is the main limitation of available drugs. Here we review the design and conduct of nOH clinical trials in patients with PD and other synucleinopathies, summarize the results of the most recently completed and ongoing trials, and discuss challenges, bottlenecks, and potential remedies.

Orthostatic Hypotension Is Associated With Cognitive Decline in Parkinson Disease

Introduction: Cognitive impairment and orthostatic hypotension (OH) are common, disabling Parkinson disease (PD) symptoms that are strongly correlated. Whether the relationship is causative or associative remains unknown. OH may occur without classic orthostatic symptoms of cerebral hypoperfusion (i.e., lightheadedness or dizziness). Whether longitudinal differences in cognition occur between symptomatic and asymptomatic OH patients has not been explored.

Objectives: We characterized the prevalence of OH, orthostatic symptoms, and cognitive impairment among PD patients and compared cognition between patients with and without OH, and between patients with symptomatic and asymptomatic OH.

Methods: Our cross-sectional, retrospective, observational study included 226 clinically diagnosed PD patients who underwent repeated standardized evaluations. Among these, 62 had longitudinal follow-up of > 3.5 years. We compared longitudinal Montreal Cognitive Assessment (MoCA) scores between patients remaining OH-free (n = 14) and those without baseline OH that developed OH (n = 28), matched for age, sex, education, and PD duration. We also compared MoCA scores between groups with asymptomatic OH (n = 13) and symptomatic OH (n = 13) matched for the same factors.

Results: In the cross-sectional analysis, OH patients had worse cognition. In the longitudinal analysis (mean follow-up = 5.3 years), OH patients had worse cognitive decline (p = 0.027). Cognitive impairment was similar between asymptomatic and symptomatic OH patients in the cross-sectional and longitudinal analyses.

Conclusions: OH is associated with cognitive impairment in PD. Further studies are needed in larger cohorts to expand our findings and to determine whether treating OH can prevent or delay cognitive dysfunction.

Neurogenic Orthostatic Hypotension: State of the Art and Therapeutic Strategies

Neurogenic orthostatic hypotension (nOH) is a subtype of orthostatic hypotension in which patients have impaired regulation of standing blood pressure due to autonomic dysfunction. Several primary and secondary causes of this disease exist. Patients may present with an array of symptoms making diagnosis difficult. This review article addresses the epidemiology, pathophysiology, causes, clinical features, and management of nOH. We highlight various pharmacological and non-pharmacological approaches to treatment, and review the recent guidelines and our approach to nOH.

Pharmacologic treatment of orthostatic hypotension

Neurogenic orthostatic hypotension (OH) is a disabling disorder caused by impairment of the normal autonomic compensatory mechanisms that maintain upright blood pressure. Nonpharmacologic treatment is always the first step in the management of this condition, but a considerable number of patients will require pharmacologic therapies. Denervation hypersensitivity and impairment of baroreflex buffering makes these patients sensitive to small doses of pressor agents. Understanding the underlying pathophysiology can help in selecting between treatment options. In general, patients with low "sympathetic reserve", i.e., those with peripheral noradrenergic degeneration (pure autonomic failure, Parkinson's disease) and low plasma norepinephrine, tend to respond better to "norepinephrine replacers" (midodrine and droxidopa). On the other hand, patients with relatively preserved "sympathetic reserve", i.e., those with impaired central autonomic pathways but spared peripheral noradrenergic fibers (multiple system atrophy) and normal or slightly reduced plasma norepinephrine, tend to respond better to "norepinephrine enhancers" (pyridostigmine, atomoxetine, and yohimbine). There is, however, a spectrum of responses within these extremes, and treatment should be individualized. Other nonspecific treatments include fludrocortisone and octreotide. The presence of associated clinical conditions, such as supine hypertension, heart failure, postprandial hypotension, PD, MSA, and diabetes need to be considered in the pharmacologic management of these patients.

Pharmacokinetics of Ampreloxetine, a Norepinephrine Reuptake Inhibitor, in Healthy Subjects and Adults with Attention-Deficit/Hyperactive Disorder or Fibromyalgia Pain

Background and Objective

Ampreloxetine is a novel norepinephrine reuptake inhibitor in development for the treatment of symptomatic neurogenic orthostatic hypotension. The objectives of this analysis were to define the pharmacokinetics of once-daily oral ampreloxetine and provide dose recommendations for clinical development.

Methods

We fitted a population pharmacokinetic model to ampreloxetine plasma concentrations from single- and multiple-ascending dose trials in healthy subjects and two phase II studies in adult subjects with attention-deficit/hyperactive disorder or fibromyalgia at doses of 2–50 mg.

Results

Ampreloxetine pharmacokinetics was best described by a two-compartment model with first-order absorption and elimination. The terminal half-life was 30–40 h, resulting in sustained drug concentrations for the entire 24-h dosing interval at steady state. Covariates of age, weight, or renal impairment did not impact ampreloxetine exposure. Cytochrome P450 2D6 phenotype had no influence on ampreloxetine exposure. Sex and smoking status were identified as statistically significant covariates, suggesting a role for cytochrome P450 1A2 in the elimination of ampreloxetine. Despite statistical significance, differences in ampreloxetine exposure in male vs female subjects and smokers vs non-smokers were not clinically meaningful at the recommended dose. At the 10-mg dose, > 75% norepinephrine transporter inhibition and < 50% serotonin transporter inhibition are anticipated for adult subjects.

Conclusions

The population pharmacokinetic model effectively described the plasma concentration–time profile of ampreloxetine after single and multiple doses. Population pharmacokinetic/pharmacodynamic analysis justified using a fixed dosing regimen with no dose adjustments across a broad population and can be used to inform dosing strategies in future clinical studies.

Clinical Trial Registration

ClinicalTrials.gov identifier numbers NCT01693692 (fibromyalgia); NCT01458340 (attention-deficit/hyperactive disorder).

Electronic supplementary material

The online version of this article (10.1007/s40262-020-00918-7) contains supplementary material, which is available to authorized users.

Differential diagnosis of orthostatic hypotension

Orthostatic hypotension (OH) is a common clinical manifestation characterized by a significant fall in blood pressure with postural change and is frequently accompanied by debilitating symptoms of orthostatic intolerance. The reported prevalence of OH ranges between 5 and 10% in middle-aged adults with a burden that increases concomitantly with age; in those over 60 years of age, the prevalence is estimated to be over 20%. Unfortunately, the clinical course of OH is not necessarily benign. OH patients are at an increased risk of adverse clinical outcomes including death, falls, cardiovascular and cerebrovascular events, syncope, and impaired quality of life. The differential diagnosis of OH is broad and includes acute precipitants as well as chronic underlying medical conditions, especially of neurological origin. Appropriate diagnosis relies on a systematic history and physical examination with particular attention to orthostatic vital signs, keeping in mind that ambient conditions during diagnostic testing may affect OH detection due to factors such as diurnal variation.

Parkinson Disease and Orthostatic Hypotension in the Elderly: Recognition and Management of Risk Factors for Falls

Parkinson disease (PD) is often associated with postural instability and gait dysfunction that can increase the risk for falls and associated consequences, including injuries, increased burden on healthcare resources, and reduced quality of life. Patients with PD have nearly twice the risk for falls and associated bone fractures compared with their general population counterparts of similar age. Although the cause of falls in patients with PD may be multifactorial, an often under-recognized factor is neurogenic orthostatic hypotension (nOH). nOH is a sustained decrease in blood pressure upon standing whose symptomology can include dizziness/lightheadedness, weakness, fatigue, and syncope. nOH is due to dysfunction of the autonomic nervous system compensatory response to standing and is a consequence of the neurodegenerative processes of PD. The symptoms associated with orthostatic hypotension (OH)/nOH can increase the risk of falls, and healthcare professionals may not be aware of the real-world clinical effect of nOH, the need for routine screening, or the value of early diagnosis of nOH when treating elderly patients with PD. nOH is easily missed and, importantly, healthcare providers may not realize that there are effective treatments for nOH symptoms that could help lessen the fall risk resulting from the condition. This review discusses the burden of, and key risk factors for, falls among patients with PD, with a focus on practical approaches for the recognition, assessment, and successful management of OH/nOH. In addition, insights are provided as to how fall patterns can suggest fall etiology, thereby influencing the choice of intervention.

Cardiovascular autonomic testing in the work-up of cerebellar ataxia: insight from an observational single center study

Background

Cerebellar ataxias are a heterogeneous group of disorders of both genetic and non-genetic origin. In sporadic cases, two entities are recognized: multiple system atrophy of cerebellar type (MSA-C) and SAOA (sporadic adult-onset ataxia). The presence of severe cardiovascular autonomic failure reliably distinguishes MSA-C from other ataxias, but it may appear only late in the disease course.

Objective

To evaluate the diagnostic yield of cardiovascular autonomic function tests in the work-up of cerebellar ataxia.

Methods

We applied a cardiovascular autonomic tests battery in consecutive patients with neurodegenerative cerebellar ataxia and matched healthy controls. We recorded the presence of both orthostatic hypotension (OH) and blood pressure falls non-fulfilling the criteria of OH (non-OH BP). Sporadic cases were followed-up for an eventual conversion to MSA-C.

Results

Forty-two patients were recruited, 19 of whom with sporadic disease (2 probable MSA-C, 6 possible MSA-C, 11 SAOA). Sporadic and hereditary cases showed no difference concerning ataxia severity at baseline. At head-up tilt, non-OH BP falls were detected in nine patients, but not in controls. This finding was significantly more frequent in sporadic cases (p = 0.006) and was detected in five out of seven patients that during follow-up converted to possible/probable MSA-C. Findings at standing test were normal in four out of nine cases with non-OH BP falls at head-up tilt.

Conclusions

A complete cardiovascular autonomic battery with head-up tilt can detect early signs of BP dysregulation which may be missed at bed-side tests, thus warranting its application in the first line work-up of cerebellar ataxias.

Electronic supplementary material

The online version of this article (10.1007/s00415-019-09684-4) contains supplementary material, which is available to authorized users.

Neurogenic Orthostatic Hypotension in Parkinson Disease: A Primer

Parkinson disease (PD) is associated with a variety of motor and non-motor clinical manifestations, including cardiovascular autonomic dysfunction. Neurogenic orthostatic hypotension (nOH) is a potentially serious manifestation of cardiovascular sympathetic failure that occurs in approximately 30% of patients with PD. Here we review the pathophysiology and effects of the condition as well as treatment considerations for patients with PD and nOH. Screening for nOH using orthostatic symptom questionnaires, orthostatic blood pressure measurements, and specialized autonomic testing is beneficial for the identification of symptomatic and asymptomatic cases because cardiac sympathetic denervation and nOH can occur even at early (premotor) stages of PD. Symptoms of nOH, such as orthostatic lightheadedness, in patients with PD, have been shown to adversely affect patient safety (with increased risk of falls) and quality of life and should prompt treatment with non-pharmacologic and, occasionally, pharmacologic measures. Patients with nOH are also at increased risk of supine hypertension, which requires balancing various management strategies. FUNDING: Lundbeck (Deerfield, IL).

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.

Orthostatic hypotension in Parkinson disease: A 7-year prospective population-based study

OBJECTIVE

To determine the frequency, evolution, and associated features of orthostatic hypotension (OH) over 7 years of prospective follow-up in a population-based, initially drug-naive Parkinson disease (PD) cohort.

METHODS

We performed repeated lying and standing blood pressure measurements in 185 patients with newly diagnosed PD and 172 matched normal controls to determine the occurrence of (1) OH using consensus-based criteria and (2) clinically significant OH (mean arterial pressure in standing position ≤75 mm Hg). We applied generalized estimating equations models for correlated data to investigate associated features of these 2 outcomes in patients with PD.

RESULTS

OH was more common in patients with PD than controls at all visits, with the relative risk increasing from 3.0 (95% confidence interval [CI] 1.6-5.8; p < 0.001) at baseline to 4.9 (95% CI 2.4-10.1; p < 0.001) after 7 years. Despite a high cumulative prevalence of OH (65.4%) and clinically significant OH (29.2%), use of antihypotensive drugs was very rare (0.5%). OH was independently associated with older age (odds ratio [OR] 1.06 per year; 95% CI 1.03-1.10), lower Mini-Mental State Examination score (OR 0.91 [0.85-0.97] per unit), and longer follow-up time (OR 1.12 [1.03-1.23] per year). Clinically significant OH was associated with the same characteristics, in addition to higher levodopa equivalent dosage (OR 1.16 [1.07-1.25] per 100 mg).

CONCLUSIONS

In this population-based study, we found OH to be a very frequent but undertreated complication in early PD, with associations to both disease-specific symptoms and drug treatment. Our findings suggest that clinicians should more actively assess and manage OH abnormalities in PD.

Orthostatic Hypotension in Parkinson Disease

Orthostatic hypotension (OH) is a sustained fall in blood pressure on standing that can cause symptoms of organ hypoperfusion. OH is associated with increased morbidity and mortality and leads to a significant number of hospital admissions. OH can be caused by volume depletion, blood loss, cardiac pump failure, large varicose veins, medications, or defective activation of sympathetic nerves and reduced norepinephrine release upon standing. Neurogenic OH is a frequent and disabling problem in patients with synucleinopathies such as Parkinson disease, multiple system atrophy, and pure autonomic failure, and it is commonly associated with supine hypertension. Several therapeutic options are available.

Orthostatic hypotension in hereditary transthyretin amyloidosis: epidemiology, diagnosis and management

Purpose

Neurogenic orthostatic hypotension is a prominent and disabling manifestation of autonomic dysfunction in patients with hereditary transthyretin (TTR) amyloidosis affecting an estimated 40–60% of patients, and reducing their quality of life. We reviewed the epidemiology and pathophysiology of neurogenic orthostatic hypotension in patients with hereditary TTR amyloidosis, summarize non-pharmacologic and pharmacological treatment strategies and discuss the impact of novel disease-modifying treatments such as transthyretin stabilizers (diflunisal, tafamidis) and RNA interference agents (patisiran, inotersen).

Methods

Literature review.

Results

Orthostatic hypotension in patients with hereditary transthyretin amyloidosis can be a consequence of heart failure due to amyloid cardiomyopathy or volume depletion due to diarrhea or drug effects. When none of these circumstances are apparent, orthostatic hypotension is usually neurogenic, i.e., caused by impaired norepinephrine release from sympathetic postganglionic neurons, because of neuronal amyloid fibril deposition.

Conclusions

When recognized, neurogenic orthostatic hypotension can be treated. Discontinuation of potentially aggravating medications, patient education and non-pharmacologic approaches should be applied first. Droxidopa (Northera^®), a synthetic norepinephrine precursor, has shown efficacy in controlled trials of neurogenic orthostatic hypotension in patients with hereditary TTR amyloidosis and is now approved in the US and Asia. Although they may be useful to ameliorate autonomic dysfunction in hereditary TTR amyloidosis, the impact of disease-modifying treatments on neurogenic orthostatic hypotension is still uninvestigated.

Role of nurses and nurse practitioners in the recognition, diagnosis, and management of neurogenic orthostatic hypotension: a narrative review

Neurogenic orthostatic hypotension (nOH) is a sustained reduction in blood pressure (BP) upon standing that is caused by autonomic dysfunction and is common among patients with a variety of neurodegenerative disorders (eg, Parkinson's disease, multiple system atrophy, pure autonomic failure). A systolic BP drop of ≥20 mmHg (or ≥10 mmHg diastolic) upon standing with little or no compensatory increase in heart rate is consistent with nOH. Symptoms of nOH include light-headedness, dizziness, presyncope, and syncope; these symptoms can severely impact patients' activities of daily living and increase the likelihood of potentially dangerous falls. Because of their patient contact, nurses and nurse practitioners can play a key role in identifying and evaluating patients at risk for nOH. It is advisable to screen for nOH in patients presenting with one or more of the following characteristics: those who have disorders associated with autonomic failure, those with episodes of falls or syncope, those with symptoms upon standing, those who are elderly or frail, or those taking multiple medications. Initial evaluations should include questions about postural symptoms and measurement of orthostatic BP and heart rate. A review of medications for potential agents that can have hypotensive effects should be performed before initiating treatment. Treatment for nOH may include non-pharmacologic measures and pharmacologic therapy. Droxidopa and midodrine are approved by the US Food and Drug Administration for the treatment of symptomatic nOH and symptomatic OH, respectively. nOH is associated with the coexistence of supine hypertension, and the two disorders must be carefully managed. In conclusion, timely screening and diagnosis of patients with nOH can streamline the path to disease management and treatment, potentially improving patient outcomes.

Six-Month Use of Droxidopa for Neurogenic Orthostatic Hypotension

Background

Droxidopa is approved for adult patients with symptomatic neurogenic orthostatic hypotension (nOH); there is limited information regarding effects on symptoms, outcomes, and quality of life (QOL) beyond two weeks of treatment.

Objective

Examine the real‐world experience of patients taking droxidopa after six months of treatment.

Methods

This non‐interventional, US‐based, prospective cohort study utilized a pharmacy hub, identifying patients who recently started droxidopa for nOH treatment. Questionnaires for fall frequency and other patient‐reported outcomes (PROs) were completed at baseline and one, three, and six months following droxidopa initiation.

Results

179 enrolled patients completed baseline surveys. Droxidopa continuation rates were high at months one, three, and six (87%, 79%, and 75%, respectively). From baseline to month one, there was significant reduction in the proportion of patients reporting falling at least once (54.1% vs. 43.0%; P = 0.0039), with similar observations at month three (52.9% vs. 44.5%; P = 0.0588) and month six (51.4% vs. 40.0%; P = 0.0339). Significant improvements from baseline to month one were observed and maintained at months three and six for most PROs, including the Orthostatic Hypotension Symptom Assessment Item 1, Short Falls Efficacy Scale‐International, Sheehan Disability Scale, Physical Component of the 8‐item Short‐Form Health Survey, and Patient Health Questionnaire‐9.

Conclusions

In this non‐interventional prospective study, fewer nOH patients reported falling after one, three, and six months of droxidopa treatment. Further, improvements reported in nOH symptoms, physical function, and QOL measures were maintained for six months following treatment initiation. Results from randomized clinical trials are required to validate the findings.

Orthostatic hypotension in patients with late-life depression: Prevalence and validation of a new screening tool

OBJECTIVES

The objective of this study was to assess the prevalence of orthostatic hypotension (OH) in a sample of late life depression (LLD) patients and to determine the validity of a standardized questionnaire, the Orthostatic Hypotension Questionnaire (OHQ). Secondarily, we wished to assess variables associated with OH.

METHODS

We conducted a cross-sectional study on 82 consecutive geriatric outpatients presenting with LLD. OH was defined as a fall in systolic blood pressure of greater than 20 mm Hg and/or 10 mm Hg on diastolic blood pressure on an orthostatic stress test from sitting to standing. Logistic regressions were used to identify factors associated with OH.

RESULTS

The prevalence of OH as measured on the orthostatic stress test and on the OHQ was 28% and 57%, respectively. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the OHQ were 69.6% (95% CI 47%-87%), 47.5% (95%CI 34%-61%), 0.54 (95% CI: 0.43-0.64), 34% (95%CI 21%-49%), and 80% (95%CI 63%-92%), respectively. Females were more likely to have OH (OR: 3.96, 95%CI 1.06-14.89, P = .041), and those married or in a common-law relationship were less likely to have OH (OR: 0.25, 95% CI 0.08-0.72, P = .011).

CONCLUSIONS

OH is common in patients with LLD conferring them a risk of gait instability and falls. Females had a higher risk of having OH while participants who were married or in a common-law relationship were less likely to have OH. Although the OHQ is a quick to administer paper-based screening test, it did not show adequate diagnostic accuracy in patients with LLD seen in a routine psychiatry clinic.

Diagnosis of multiple system atrophy

Multiple system atrophy (MSA) may be difficult to distinguish clinically from other disorders, particularly in the early stages of the disease. An autonomic-only presentation can be indistinguishable from pure autonomic failure. Patients presenting with parkinsonism may be misdiagnosed as having Parkinson disease. Patients presenting with the cerebellar phenotype of MSA can mimic other adult-onset ataxias due to alcohol, chemotherapeutic agents, lead, lithium, and toluene, or vitamin E deficiency, as well as paraneoplastic, autoimmune, or genetic ataxias. A careful medical history and meticulous neurological examination remain the cornerstone for the accurate diagnosis of MSA. Ancillary investigations are helpful to support the diagnosis, rule out potential mimics, and define therapeutic strategies. This review summarizes diagnostic investigations useful in the differential diagnosis of patients with suspected MSA. Currently used techniques include structural and functional brain imaging, cardiac sympathetic imaging, cardiovascular autonomic testing, olfactory testing, sleep study, urological evaluation, and dysphagia and cognitive assessments. Despite advances in the diagnostic tools for MSA in recent years and the availability of consensus criteria for clinical diagnosis, the diagnostic accuracy of MSA remains sub-optimal. As other diagnostic tools emerge, including skin biopsy, retinal biomarkers, blood and cerebrospinal fluid biomarkers, and advanced genetic testing, a more accurate and earlier recognition of MSA should be possible, even in the prodromal stages. This has important implications as misdiagnosis can result in inappropriate treatment, patient and family distress, and erroneous eligibility for clinical trials of disease-modifying drugs.

Orthostatic heart rate changes in patients with autonomic failure caused by neurodegenerative synucleinopathies

OBJECTIVE

Blunted tachycardia during hypotension is a characteristic feature of patients with autonomic failure, but the range has not been defined. This study reports the range of orthostatic heart rate (HR) changes in patients with autonomic failure caused by neurodegenerative synucleinopathies.

METHODS

Patients evaluated at sites of the U.S. Autonomic Consortium (NCT01799915) underwent standardized autonomic function tests and full neurological evaluation.

RESULTS

We identified 402 patients with orthostatic hypotension (OH) who had normal sinus rhythm. Of these, 378 had impaired sympathetic activation (ie, neurogenic OH) and based on their neurological examination were diagnosed with Parkinson disease, dementia with Lewy bodies, pure autonomic failure, or multiple system atrophy. The remaining 24 patients had preserved sympathetic activation and their OH was classified as nonneurogenic, due to volume depletion, anemia, or polypharmacy. Patients with neurogenic OH had twice the fall in systolic blood pressure (SBP; -44 ± 25 vs -21 ± 14 mmHg [mean ± standard deviation], p < 0.0001) but only one-third of the increase in HR of those with nonneurogenic OH (8 ± 8 vs 25 ± 11 beats per minute [bpm], p < 0.0001). A ΔHR/ΔSBP ratio of 0.492 bpm/mmHg had excellent sensitivity (91.3%) and specificity (88.4%) to distinguish between patients with neurogenic from nonneurogenic OH (area under the curve = 0.96, p < 0.0001). Within patients with neurogenic OH, HR increased more in those with multiple system atrophy (p = 0.0003), but there was considerable overlap with patients with Lewy body disorders.

INTERPRETATION

A blunted HR increase during hypotension suggests a neurogenic cause. A ΔHR/ΔSBP ratio < 0.5 bpm/mmHg is diagnostic of neurogenic OH. Ann Neurol 2018;83:522-531.

Treatment of autonomic dysfunction in Parkinson disease and other synucleinopathies

Dysfunction of the autonomic nervous system afflicts most patients with Parkinson disease and other synucleinopathies such as dementia with Lewy bodies, multiple system atrophy, and pure autonomic failure, reducing quality of life and increasing mortality. For example, gastrointestinal dysfunction can lead to impaired drug pharmacodynamics causing a worsening in motor symptoms, and neurogenic orthostatic hypotension can cause syncope, falls, and fractures. When recognized, autonomic problems can be treated, sometimes successfully. Discontinuation of potentially causative/aggravating drugs, patient education, and nonpharmacological approaches are useful and should be tried first. Pathophysiology-based pharmacological treatments that have shown efficacy in controlled trials of patients with synucleinopathies have been approved in many countries and are key to an effective management. Here, we review the treatment of autonomic dysfunction in patients with Parkinson disease and other synucleinopathies, summarize the nonpharmacological and current pharmacological therapeutic strategies including recently approved drugs, and provide practical advice and management algorithms for clinicians, with focus on neurogenic orthostatic hypotension, supine hypertension, dysphagia, sialorrhea, gastroparesis, constipation, neurogenic overactive bladder, underactive bladder, and sexual dysfunction. © 2018 International Parkinson and Movement Disorder Society.