Standing worsens cognitive functions in patients with neurogenic orthostatic hypotension

Orthostatic hypotension and neurocognitive disorders in older women: Results from the EPIDOS cohort study

BACKGROUND

Although it is well-admitted that cardiovascular health affects cognition, the association between orthostatic hypotension (OH) and cognition remains unclear. The objectives of the present study were i) to determine among the EPIDOS cohort (EPIdémiologie de l'OStéoporose) whether OH was cross-sectionally associated with cognitive impairment at baseline, and ii) whether baseline OH could predict incident cognitive decline after 7 years of follow-up.

METHODS

Systolic and Diastolic Blood Pressure (SBP and DBP) changes while standing (ie, ΔSBP and ΔDBP, in %) were measured at baseline among 2,715 community-dwelling older women aged 75 years and older using no antihypertensive drugs from the French EPIDOS cohort. OH was defined as a decrease in SBP ≥20 mmHg and/or a decrease in DBP ≥10 mmHg within 3 min after standing. Cognitive impairment was defined as a Short Portable Mental Status Questionnaire (SPMSQ) score <8 (/10). Among those without cognitive impairment at baseline, a possible incident onset of cognitive decline was then sought after 7 years of follow-up among 257 participants.

RESULTS

Baseline ΔSBP was associated with baseline cognitive impairment (adjusted OR = 1.01, p = 0.047), but not with incident onset of cognitive decline after 7 years (adjusted OR = 0.98, p = 0.371). Neither baseline OH nor baseline ΔDBP were associated with cognitive impairment neither at baseline (p = 0.426 and p = 0.325 respectively) nor after 7 years (p = 0.180 and p = 0.345 respectively).

CONCLUSIONS

SBP drop while standing, but neither OH per se nor DBP drop while standing, was associated with baseline cognitive impairment in older women. The relationship between OH and cognitive impairment appears more complex than previously expected.

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.

Cognitive Profile and Its Evolution in a Cohort of Multiple System Atrophy Patients

Introduction: Cognitive decline is not a characteristic feature of multiple system atrophy (MSA), but recent evidence suggests cognitive impairment as an integral part of the disease. We aim to describe the cognitive profile and its progression in a cohort of patients with MSA.

Methods: We retrospectively selected patients referred to our department with a clinical diagnosis of MSA who were evaluated at least once a year during the course of the disease and underwent a comprehensive neuropsychological evaluation.

Results: At the first evaluation (T0), 37 out of 60 patients (62%) were cognitively impaired, mainly (76%) in attention and executive functioning. Thirteen patients were impaired in one cognitive domain and 24 in more than one cognitive domain. Six out of the 24 had dementia. Twenty patients underwent a follow-up evaluation (T1) after a mean of 16.6 ± 9.3 months from the first evaluation (T0). Eight out of 20 patients were cognitively normal at both T0 and T1. Seven out of 12 patients presented with stable cognitive impairment at T1, while cognitive decline progressed in five patients. Patients with progression in cognitive decline performed significantly worse at T0 than cognitively stable patients. Education was significantly different between patients with and without cognitive impairment. No other differences in demographic and clinical variables and autonomic or sleep disturbances were found. Patients with dementia were older at disease onset and at T0 and had lower education and disease duration at T0 compared to those in other groups.

Conclusions: In patients with MSA, we observed three different cognitive profiles: normal cognition, stable selective attention-executive deficits, and progressive cognitive deficits evolving to dementia. The detection of cognitive impairment in patients with suspected MSA suggests the need for comprehensive and longitudinal neuropsychological evaluation.

Management of Orthostatic Hypotension, Postprandial Hypotension, and Supine Hypertension

This review provides recommendations for the treatment of neurogenic orthostatic hypotension (nOH), postprandial hypotension, and supine hypertension. It focuses on novel treatment strategies and new insights into the mechanism underlying these conditions. Our goal is to provide practical advice for clinicians on how to screen, diagnose, and treat these conditions with nonpharmacological and pharmacological approaches. For each disorder, we offered a stepwise recommendation on how to apply these new concepts to successfully ameliorate the symptoms associated with OH to prevent syncope and falls. The management of OH in patients who also have supine hypertension requires special considerations and pharmacotherapy. It is noteworthy that there are few therapeutic options for OH and only two Food and Drug Administration-approved drugs for the treatment of OH and nOH based on randomized clinical trials. We will use these studies to develop evidence-based guidelines for OH. The research is limited for postprandial hypotension and supine hypertension, and therefore the recommendations will be based on small studies, clinical expertise, and, above all, an understanding of the underlying pathophysiology.

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.

Neurogenic orthostatic hypotension impairs information processing speed and attention

Neurogenic orthostatic hypotension (NOH) is characterized by a drop in systolic blood pressure (SBP) ≥20 mmHg or diastolic blood pressure (DBP) ≥10 mmHg within three minutes of upright posture. NOH is common in the elderly population. This group of individuals is at an increased risk for deficits in multiple cognitive domains such as information processing speed (IPS) and attention. The objective of the current study was to investigate the change in IPS and attention during head-up tilt (HUT) in patients with NOH compared to controls. Cognitive function was assessed in the supine and HUT positions using the symbol digit modalities test (SDMT) which assesses IPS and the Stroop Test which measures attention. 40 participants completed the study, 20 controls (age 64.50 ± 9.25) and 20 NOH patients (age 69.55 ± 7.43) with associated conditions of Parkinson's disease (n = 11), multiple systems atrophy (n = 3), early Lewy body dementia (n = 1) and idiopathic NOH (n = 5). NOH patients had no difference in IPS between supine (43.20 ± 15.26) and HUT (42.90 ± 14.33; p = .77). Controls had significantly faster IPS in the HUT position (69.90 ± 12.02) compared to supine (63.55 ± 9.96; p < .001). NOH patients had significantly slower IPS in both the supine and HUT position compared to controls (p < .001). Attention in the HUT position was significantly worse in NOH patients (-14.86 ± 8.96) compared to controls (-8.68 ± 7.13; p = .029). During HUT, NOH patients experienced a significant decrease in mean SBP by -64.11 ± 18.96 from baseline, whereas controls only had a mean decrease of -5.69 ± 7.65. It is evident that NOH patients have impaired IPS and attention compared to controls and likely plays an important role in the morbidity of these individuals.

Scientific Advances in and Clinical Approaches to Small-Fiber Polyneuropathy: A Review

IMPORTANCE

Small-fiber polyneuropathy involves preferential damage to the thinly myelinated A-delta fibers, unmyelinated C sensory fibers, or autonomic or trophic fibers. Although this condition is common, most patients still remain undiagnosed and untreated because of lagging medical and public awareness of research advances. Chronic bilateral neuropathic pain, fatigue, and nausea are cardinal symptoms that can cause disability and dependence, including pain medication dependence.

OBSERVATIONS

Biomarker confirmation is recommended, given the nonspecificity of symptoms. The standard test involves measuring epidermal neurite density within a 3-mm protein gene product 9.5 (PGP9.5)-immunolabeled lower-leg skin biopsy. Biopsies and autonomic function testing confirm that small-fiber neuropathy not uncommonly affects otherwise healthy children and young adults, in whom it is often associated with inflammation or dysimmunity. A recent meta-analysis concluded that small-fiber neuropathy underlies 49% of illnesses labeled as fibromyalgia. Initially, patients with idiopathic small-fiber disorders should be screened by medical history and blood tests for potentially treatable causes, which are identifiable in one-third to one-half of patients. Then, secondary genetic testing is particularly important for familial and childhood cases. Treatable genetic causes include Fabry disease, transthyretin and primary systemic amyloidosis, hereditary sensory autonomic neuropathy-1, and ion-channel mutations. Immunohistopathologic evidence suggests that small-fiber dysfunction and denervation, especially of blood vessels, contributes to diverse symptoms, including postexertional malaise, postural orthostatic tachycardia, and functional gastrointestinal distress. Preliminary evidence implicates acute or chronic autoreactivity in some cases, particularly in female patients and otherwise healthy children and young adults. Different temporal patterns akin to Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy have been described; here, corticosteroids and immunoglobulins, which are often efficacious for inflammatory neuropathic conditions, are increasingly considered.

CONCLUSIONS AND RELEVANCE

Because small fibers normally grow throughout life, improving contributory conditions may permit regrowth, slow progression, and prevent permanent damage. The prognosis is often hopeful for improving quality of life and sometimes for abatement or resolution, particularly in the young and otherwise healthy individuals. Examples include diabetic, infectious, toxic, genetic, and inflammatory causes. The current standard of care requires prompt diagnosis and treatment, particularly in children and young adults, to restore life trajectory. Consensus diagnostic and tracking metrics should be established to facilitate treatment trials.

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.

Trouble Concentrating is an Easily Overlooked Symptom of Orthostatic Hypotension in Early Parkinson's Disease

BACKGROUND

Trouble concentrating during orthostasis is one symptom of orthostatic hypotension (OH), but it is often ignored in clinical practice because OH incorporates many nonspecific symptoms. Blunted cognition during orthostasis may affect various aspects of the clinical status of patients with Parkinson's disease (PD), but its impact on drug-naïve, early PD patients is not clear.

OBJECTIVE

This study investigated the association between trouble concentrating during orthostasis and orthostatic blood pressure changes and the influence of trouble concentrating during orthostasis on other non-motor symptoms and health-related quality of life in de novo PD.

METHODS

A total of 124 patients with early PD were enrolled and received a structured clinical interview, physical examination, and validated questionnaires to evaluate motor and non-motor symptoms and quality of life. Disturbed concentration was evaluated with question 5 of the Orthostatic Hypotension Questionnaire system assessment (part I). Supine blood pressure and blood pressure change during tilt table testing were recorded, and any association was analyzed.

RESULTS

Among the study population, 76 (61.3%) patients had trouble concentrating. Patients with blunted concentration had a steeper decrease in blood pressure during orthostasis. The score for trouble concentrating was positively associated with non-motor symptoms and quality of life scores.

CONCLUSIONS

Trouble concentrating when standing was a frequent finding in early, drug-naïve PD patients. It was positively associated with non-motor burden, mood and quality of life in patients with PD. OH was correlated with the incidence of trouble concentrating. Such findings complicate treatment but provide valuable information for managing early PD.

Orthostatic hypotension and cognition in older adults: A systematic review and meta-analysis

BACKGROUND

Orthostatic hypotension (OH) is common in older adults with reported prevalence rates of 5-40%. A direct link between OH and cognitive performance has been proposed due to impaired vascular autoregulation.

AIM

To systematically assess the literature of the association between OH and cognitive performance in older adults.

METHODS

Literature search of MEDLINE, Embase, Cochrane Central Register of Controlled Trials and PsycINFO from inception to May 2017. Studies were included if OH and cognition were assessed in subjects of mean or median age ≥65 years. Risk of bias was assessed with the Newcastle Ottawa Scale.

RESULTS

Of 3266 studies screened, 32 studies (22 cross-sectional; 10 longitudinal) reporting data of 28,980 individuals were included. OH prevalence ranged from 3.3% to 58%. Of the 32 studies, 18 reported an association between OH and worse cognitive performance and 14 reported no association. Mini Mental State Examination (MMSE) was the most commonly used cognitive assessment tool. Studies using more than one cognitive assessment tool were more likely to find an association between OH and worse cognition. OH was significantly associated with a lower MMSE mean score (mean difference - 0.51 (95% CI: -0.85, -0.17, p = 0.003)) and an increased risk of cognitive impairment (OR 1.19 (95% CI, 1.00-1.42, p = 0.048)).

CONCLUSIONS

OH is common in older populations and is associated with worse cognition expressed as lower MMSE scores. Use of MMSE alone as a cognitive assessment tool may underestimate the association. It is yet unclear whether the association between OH and worse cognitive performance is causative.

Cognitive fluctuations in Parkinson's disease dementia: blood pressure lability as an underlying mechanism

Background

Cognitive fluctuations refer to alterations in cognition, attention, or arousal occurring over minutes to hours, most commonly in patients with dementias associated with advanced Lewy body pathology. Their pathophysiologic underpinning remains undetermined.

Case presentation

We documented serial blood pressure (BP) measurements in an 86-year-old man with Parkinson’s disease dementia experiencing cognitive fluctuations during an office visit. This patient’s associated dysautonomia included labile BP with orthostatic hypotension and nocturnal hypertension. A spontaneous episode of unresponsiveness occurred while his BP was 72/48. His mental status began to recover immediately as his BP increased to 84/56 when he was placed in a recumbent position; it fully returned to baseline when it reached 124/66 within 1 min. His heart rate remained in the mid-to-high 60s throughout. Subsequent treatment with midodrine markedly reduced the frequency of cognitive fluctuations.

Conclusions

Paroxysmal hypotension may represent an explanatory mechanism for cognitive fluctuations, a common clinical feature in patients with Parkinson’s disease dementia and dementia with Lewy bodies.

Specific symptoms may discriminate between fibromyalgia patients with vs without objective test evidence of small-fiber polyneuropathy

In patients with fibromyalgia, tingling and numbness sensations and symptoms indicative of peripheral autonomic dysfunction might be useful in predicting objective diagnosis of small-fiber polyneuropathy.

Introduction:

Multiple studies now confirm that ∼40% of patients with fibromyalgia syndrome meet diagnostic criteria for small-fiber polyneuropathy (SFPN) and have objective pathologic or physiologic evidence of SFPN, whereas 60% do not. Given possibilities that tens or hundreds of millions globally could have SFPN, developing screening tools becomes important.

Objectives:

This analysis explored whether specific symptoms might help distinguish these fibromyalgia endophenotypes.

Methods:

With institutional review board approval, all adults tested for SFPN by distal-leg skin biopsy or autonomic function testing at Massachusetts General Hospital in 2014 to 2015 were queried about symptoms. Inclusion required a physician's fibromyalgia syndrome diagnosis plus meeting the American College of Rheumatology 2010 Fibromyalgia Criteria. The primary outcome was the validated Small-fiber Symptom Survey, which captures severity of all known SFPN-associated symptoms. The Composite Autonomic Symptom Score-31, Short-Form Health Survey-36, and Short-Form McGill Pain Questionnaires provided secondary outcomes.

Results:

Among the 39 participants, 14 had test-confirmed SFPN (SFPN+) and 25 did not (SFPN−). Their pain severity did not differ. Paresthesias (“tingling”) were different (worse) in the SFPN+ group (3.14 ± 0.9 vs 2.28 ± 1.1; P = 0.16). Their component subscore for dysautonomia symptoms was also worse (10.42 ± 4.0 vs 7.16 ± 4.0; P = 0.019). Receiver operating characteristic analyses revealed that each item had fair diagnostic utility in predicting SFPN, with areas under the curve of 0.729. No secondary questionnaires discriminated significantly.

Conclusion:

Among patients with fibromyalgia, most symptoms overlap between those with or without confirmed SFPN. Symptoms of dysautonomia and paresthesias may help predict underlying SFPN. The reason to screen for SFPN is because—unlike fibromyalgia—its medical causes can sometimes be identified and definitively treated or cured.

Pharmacotherapy of Cardiovascular Autonomic Dysfunction in Parkinson Disease

Cardiovascular autonomic dysfunctions, including neurogenic orthostatic hypotension, supine hypertension and post-prandial hypotension, are relatively common in patients with Parkinson disease. Recent evidence suggests that early autonomic impairment such as cardiac autonomic denervation and even neurogenic orthostatic hypotension occur prior to the appearance of the typical motor deficits associated with the disease. When neurogenic orthostatic hypotension develops, patients with Parkinson disease have an increased risk of mortality, falls, and trauma-related to falls. Neurogenic orthostatic hypotension reduces quality of life and contributes to cognitive decline and physical deconditioning. The co-existence of supine hypertension complicates the treatment of neurogenic orthostatic hypotension because it involves the use of drugs with opposing effects. Furthermore, treatment of neurogenic orthostatic hypotension is challenging because of few therapeutic options; in the past 20 years, the US Food and Drug Administration approved only two drugs for the treatment of this condition. Small, open-label or randomized studies using acute doses of different pharmacologic probes suggest benefit of other drugs as well, which could be used in individual patients under close monitoring. This review describes the pathophysiology of neurogenic orthostatic hypotension and supine hypertension in Parkinson disease. We discuss the mode of action and therapeutic efficacy of different pharmacologic agents used in the treatment of patients with cardiovascular autonomic failure.

Orthostatic hypotension: prevalence and associated risk factors among the ambulatory elderly in an Asian population

INTRODUCTION

The prevalence of orthostatic hypotension (OH) among the elderly population in Singapore, as defined by a decline in blood pressure upon a change in position, is not well-established. Studies associate OH with clinically significant outcomes such as falls. This study aims to determine the prevalence of OH among elderly patients attending a public primary care clinic (polyclinic) for chronic disease management, and examine the relationships between postulated risk factors and OH.

METHODS

Patients aged ≥ 65 years attending a typical polyclinic in Geylang were identified and targeted for recruitment at the study site. A questionnaire on symptoms and postulated risk factors was administered, followed by supine and standing blood pressure measurements. Cross-sectional analysis was performed with independent sample t-test for continuous data and chi-square test for categorical data. Prevalence rate ratios with 95% confidence interval were calculated for the latter.

RESULTS

A total of 364 multiethnic patients participated in the study. The prevalence of OH was 11.0%. Older age, comorbidities such as cardiac failure and kidney disease, being physically inactive at work, fatigue, self-reported dizziness in the past year, and the use of loop diuretics were found to be significantly associated with OH.

CONCLUSION

About one in ten elderly patients at a local polyclinic was affected by OH, which was associated with multiple factors. Some of these factors are modifiable and can be addressed to reduce the incidence of OH.

Orthostatic Hypotension Predicts Cognitive Impairment in the Elderly: Findings from a Cohort Study

BACKGROUND

Orthostatic hypotension (OH) is a known risk factor for cerebral ischemia, but its correlation with cognitive impairment (CI) is not well established.

OBJECTIVE

The aim of this study is to explore the relationship between OH and CI in the elderly.

METHODS

The study group consisted of 44 OH patients who presented with drowsiness, vertigo, and fatigue between January 2009 and December 2011 (OH group). Eighty-eight healthy elderly were paired with those in the OH group in a 1:2 based on their education levels (NOH group). Baseline sociodemographic information and cognition-related measures were collected for both groups. Cognitive function was assessed 4 years later using MMSE.

RESULTS

The overall incidence of CI was 14.0% among the 114 subjects who completed the follow-up assessment. There was a significant difference in the incidence of CI between the OH group (23.7%) and the NOH group (9.2%) (χ² = 4.399, P = 0.036). After excluding the influence of age (OR = 1.199, 95% CI: 1.072-1.340, P = 0.001) and education years (OR = 0.568, 95% CI: 0.371-0.869, P = 0.009), OH (OR = 4.047, 95% CI: 1.144-14.313, P = 0.030) became an independent risk factor for CI.

CONCLUSION

OH can lead to CI. We suggest that future studies, with a larger sample size, use OH exposure time instead of OH exposure population to verify the conclusion of this study.

Clinical Relevance of Orthostatic Hypotension in Neurodegenerative Disease

The autonomic nervous system appears to be uniquely susceptible to degeneration in disorders of α-synuclein pathology. Clinically, autonomic dysfunction in these disorders manifests as neurogenic orthostatic hypotension (nOH), a condition that results in substantial morbidity and mortality. nOH results from pathology affecting either the central autonomic pathways or peripheral autonomic nerve fibers. Determining the localization and pathophysiology of nOH is critical in effectively managing this disorder and selecting appropriate treatment options. In this review, we discuss the pathophysiology of nOH with respect to the various α-synuclein-related neurodegenerative conditions. We highlight the associated clinical features, including gait instability, rapid eye movement behavior disorder, and hyposmia. We also review the current pharmacologic treatment options for nOH. Overall, the goals of therapy are to improve symptoms and prevent syncope and falls. Non-pharmacologic interventions should be introduced first, followed by carefully selected pharmacologic therapies. Treatment decisions should be directed by an understanding of the underlying pathophysiology, as well as the comorbidities and potential contributing factors present in each individual patient.

Effect of orthostatic hypotension on sustained attention in patients with autonomic failure

INTRODUCTION

Orthostatic hypotension has been associated with impaired cognitive function, but cognitive function during orthostatic hypotension has hardly been studied. We studied the effect of orthostatic hypotension, induced by head-up tilt (HUT), on sustained attention in patients with autonomic failure.

METHODS

We studied the sustained attention to response task (SART) in the supine position and during HUT in 10 patients with autonomic failure and 10 age-matched and sex-matched controls. To avoid syncope, the tilting angle was tailored to patients to reach a stable systolic blood pressure below 100 mm Hg. Controls were all tilted at an angle of 60°. Cerebral blood flow velocity, blood pressure and heart rate were measured continuously.

RESULTS

In patients, systolic blood pressure was 61.4 mm Hg lower during HUT than in the supine position (p<0.001). Patients did not make more SART errors during HUT than in the supine position (-1.3 errors, p=0.3). Controls made 2.3 fewer errors during SART in the HUT position compared to the supine position (p=0.020). SART performance led to an increase in systolic blood pressure (+11.8 mm Hg, p=0.018) and diastolic blood pressure (+5.8 mm Hg, p=0.017) during SART in the HUT position, as well as to a trend towards increased cerebral blood flow velocity (+3.8 m/s, p=0.101).

DISCUSSION

Orthostatic hypotension in patients with autonomic failure was not associated with impaired sustained attention. This might partly be explained by the observation that SART performance led to a blood pressure increase. Moreover, the upright position was associated with better performance in controls and, to a lesser extent, also in patients.

Immunotherapy Prospects for Painful Small-fiber Sensory Neuropathies and Ganglionopathies

The best-known peripheral neuropathies are those affecting the large, myelinated motor and sensory fibers. These have well-established immunological causes and therapies. Far less is known about the somatic and autonomic "small fibers"; the unmyelinated C-fibers, thinly myelinated A-deltas, and postganglionic sympathetics. The small fibers sense pain and itch, innervate internal organs and tissues, and modulate the inflammatory and immune responses. Symptoms of small-fiber neuropathy include chronic pain and itch, sensory impairment, edema, and skin color, temperature, and sweating changes. Small-fiber polyneuropathy (SFPN) also causes cardiovascular, gastrointestinal, and urological symptoms, the neurologic origin of which often remains unrecognized. Routine electrodiagnostic study does not detect SFPN, so skin biopsies immunolabeled to reveal axons are recommended for diagnostic confirmation. Preliminary evidence suggests that dysimmunity causes some cases of small-fiber neuropathy. Several autoimmune diseases, including Sjögren and celiac, are associated with painful small-fiber ganglionopathy and distal axonopathy, and some patients with "idiopathic" SFPN have evidence of organ-specific dysimmunity, including serological markers. Dysimmune SFPN first came into focus in children and teenagers as they lack other risk factors, for example diabetes or toxic exposures. In them, the rudimentary evidence suggests humoral rather than cellular mechanisms and complement consumption. Preliminary evidence supports efficacy of corticosteroids and immunoglobulins in carefully selected children and adult patients. This paper reviews the evidence of immune causality and the limited data regarding immunotherapy for small-fiber-predominant ganglionitis, regional neuropathy (complex regional pain syndrome), and distal SFPN. These demonstrate the need to develop case definitions and outcome metrics to improve diagnosis, enable prospective trials, and dissect the mechanisms of small-fiber neuropathy.

Potential Interactions between the Autonomic Nervous System and Higher Level Functions in Neurological and Neuropsychiatric Conditions

The autonomic nervous system (ANS) maintains the internal homeostasis by continuously interacting with other brain structures. Its failure is commonly observed in many neurological and neuropsychiatric disorders, including neurodegenerative and vascular brain diseases, spinal cord injury, and peripheral neuropathies. Despite the different underlying pathophysiological mechanisms, ANS failure associates with various forms of higher level dysfunctions, and may also negatively impact on patients’ clinical outcome. In this review, we will discuss potential relationships between ANS and higher level dysfunctions in a selection of neurological and neuropsychiatric disorders. In particular, we will focus on the effect of a documented fall in blood pressure fulfilling the criteria for orthostatic hypotension and/or autonomic-reflex impairment on cognitive performances. Some evidence supports the hypothesis that cardiovascular autonomic failure may play a negative prognostic role in most neurological disorders. Despite a clear causal relationship between ANS involvement and higher level dysfunctions that is still controversial, this might have implications for neuro-rehabilitation strategies aimed at improving patients’ clinical outcome.

Reliability and reactivity of the prefrontal hemodynamic responses in essential hypertension: a functional near infrared spectroscopy study

Prefrontal (PFC) cerebral vasoreactivity may be altered in hypertension but has not been studied during postural change and carbon dioxide (CO2) rebreathing. In this study, a dual procedure of 5% CO2 rebreathing with positional change (standing to supine and reverse) was performed on normotensive (N = 24) and essential hypertensive males (N = 16) (18-55 years) to assess reliability of PFC responses using functional near infrared spectroscopy. The groups (matched on age levels, N = 13) were also compared on their hemodynamic reactivity (change of oxyhemoglobin or total hemoglobin as a function of change in end tidal CO2). Test-retest reliability within one session and 7 days later was moderate to high (intraclass correlation coefficient = .63-.901) in both normotensive and hypertensive groups for all hemodynamic measures; whereas reliability of reactivity measures for oxyhemoglobin and total hemoglobin was moderate (intraclass correlation coefficient = .68-.762). Functional near infrared spectroscopy-measured PFC hemodynamic responses are highly reproducible in normotensive and adult essential hypertensive males.

Cognitive dysfunction in postural tachycardia syndrome

Mental clouding is an almost universal complaint among patients with postural tachycardia syndrome (POTS) but remains poorly understood. Thus, we have determined whether POTS patients exhibit deficits during neuropsychological testing relative to healthy subjects. A comprehensive battery of validated neuropsychological tests was administered to 28 female POTS patients and 24 healthy subjects in a semi-recumbent position. Healthy subjects were matched to POTS patients on age and gender. Selective attention, a primary outcome measure, and cognitive processing speed were reduced in POTS patients compared with healthy subjects (Ruff 2&7 Speed t-score: 40±9 compared with 49±8; P=0.009; Symbol Digit Modalities Test t-score: 45±12 compared with 51±8; P=0.011). Measures of executive function were also lower in POTS patients (Trails B t-score: 46±8 compared with 52±8; P=0.007; Stroop Word Color t-score: 45±10 compared with 56±8; P=0.001), suggesting difficulties in tracking and mental flexibility. Measures of sustained attention, psychomotor speed, memory function or verbal fluency were not significantly different between groups. The present study provides evidence for deficits in selective attention and cognitive processing in patients with POTS, in the seated position when orthostatic stress is minimized. In contrast, other measures of cognitive function, including memory assessments, were not impaired in these patients, suggesting selectivity in these deficits. These findings provide new insight into the profile of cognitive dysfunction in POTS and provide the basis for further studies to identify clinical strategies to better manage the mental clouding associated with this condition.

Cognitive and sleep features of multiple system atrophy: review and prospective study

BACKGROUND

The profile and degree of cognitive impairment in Multiple System Atrophy (MSA) and the impact of sleep disorders, REM sleep behavior disorder (RBD) in particular, in parkinsonism-related cognitive deficits are currently being debated.

SUMMARY

We reviewed the cognitive, affective and sleep findings in MSA and also carried out a longitudinal investigation of 10 MSA patients. At the first evaluation, 3 patients showed isolated cognitive deficits. After a mean of 16 months, these patients remained unchanged, while 1 patient worsened from a normal condition. No significant differences emerged when the cognitive, affective and video-polysomnographic findings of MSA-P and MSA-C were compared. Depression was present in half of the patients, although it did not influence their cognitive performance. Comparisons between the first and second evaluation data showed significant worsening in visual attention and in ADL/IADL and UMSARS.

KEY MESSAGES

Isolated cognitive deficits are evidenced in a minority of MSA patients with the absence of a clear-cut diagnosis of dementia in the early stages of the disease. Attention and executive functions are often impaired. This study with a short follow-up period showed that RBD, although present in almost all patients affected by MSA, does not appear a clear early marker of cognitive impairment. Future longer-term studies with a larger patient sample are thus encouraged.

Persistence and Prognostic Implications of Orthostatic Hypotension in Older Individuals with Mild-to-Moderate Dementia

AIM

To study the course and prognostic implications of orthostatic hypotension (OH) in older individuals with mild-to-moderate dementia.

METHODS

Referrals to outpatient clinics specialising in old age psychiatry and geriatric medicine in the counties of Rogaland and Hordaland in western Norway with a first-time diagnosis of mild dementia were consecutively asked for inclusion. A total of 211 participants underwent a comprehensive baseline assessment with annual follow-ups. Patients with OH at both baseline and the 1-year follow-up were classified as having persistent OH. Outcome measures were the Mini-Mental State Examination (MMSE), the Clinical Dementia Rating sum of boxes (CDR-SB), and time to death.

RESULTS

From baseline to the 4-year follow-up, 30-45% of the participants had OH at each follow-up. In multivariable analysis, persistent OH was not significantly associated with either the longitudinal course of MMSE or CDR-SB scores or survival.

CONCLUSIONS

OH was moderately prevalent over 4 years in older individuals with mild dementia, and persistent OH did not predict either cognitive or functional decline or survival.

Lack of orthostatic symptoms in dementia patients with orthostatic hypotension

PURPOSE

Orthostatic hypotension (OH) is common and increases with age. OH is part of the autonomic dysfunction in dementia with Lewy bodies (DLB). Commonly OH is diagnosed when the patient falls which is a risk factor of premature death. Our objective was to systematically investigate the clinical symptoms associated with measurement of OH in different neurodegenerative dementias and normal controls (NC).

METHODS

154 patients [50 DLB, 50 Alzheimer's disease (AD), 54 AD and vascular components (ADvasc)] were examined with systolic and diastolic blood pressure measurements in supine position, immediately after standing up and after 1, 3, 5 and 10 min of standing. They were compared with 50 NC. Orthostatic symptoms were registered according to a predefined protocol.

RESULTS

Twenty-seven percent of all the investigated individuals reported OH symptoms during the measurement while 43% fulfilled the criteria of OH. Sixty-three percent of orthostatic patients did not have any symptoms during the measurement. The prevalence of any orthostatic symptoms during the measurement differed significantly (p < 0.001) between the diagnostic groups with 40% in DLB patients, 37% in ADvasc, 28% in AD and 2% in NC. The most frequent symptom was dizziness 13.7%.

CONCLUSIONS

Classical orthostatic symptoms are absent in the majority of dementia patients with OH. The orthostatic reaction must therefore be routinely measured in this patient group. This is particularly important for patients with DLB where falls as a result of OH are common.

Neurogenic orthostatic hypotension in Parkinson's disease: evaluation, management, and emerging role of droxidopa

Neurogenic orthostatic hypotension (nOH) is due to failure of the autonomic nervous system to regulate blood pressure in response to postural changes due to an inadequate release of norepinephrine, leading to orthostatic hypotension and supine hypertension. nOH is common in Parkinson’s disease (PD). Prevalence varies throughout the course of PD, ranging from 40% to 60%, and resulting in symptomatic nOH in approximately half. Symptomatic nOH, including lightheadedness, can limit daily activities and lead to falls. Symptomatic nOH can also limit therapeutic options for treating PD motor symptoms. Clinical evaluation should routinely include symptom assessment and blood pressure measurement of supine, sitting, and 3-minute standing; 24-hour ambulatory blood pressure monitoring can also be helpful. Non-pharmacological management of symptomatic nOH involves education, physical maneuvers, and adequate hydration. Current pharmacological treatment of symptomatic nOH includes salt supplement, fludrocortisone, midodrine, pyridostigmine, and other empiric medications. Despite these options, treatment of symptomatic nOH remains suboptimal, often limited by severe increases in supine blood pressure. Droxidopa, an oral prodrug converted by decarboxylation to norepinephrine, is a promising therapeutic option for symptomatic nOH in PD, improving symptoms of nOH, daily activities, falls, and standing systolic blood pressure in several recent trials. These trials demonstrated short-term efficacy and tolerability, with comparable increases in standing and supine blood pressures. Longer-term studies are ongoing to confirm durability of treatment effect.

Cognitive function in peripheral autonomic disorders

Objective

aims of the current study were 1) to evaluate global cognitive function in patients with autonomic failure (AF) of peripheral origin and 2) to investigate the effect of a documented fall in blood pressure (BP) fulfilling the criteria for orthostatic hypotension (OH) on cognitive performances.

Methods

we assessed 12 consecutive patients (10 males, 68±7 years old) with pure AF (PAF) or autoimmune autonomic neuropathy (AAN) and 12 age- and gender-matched controls. All patients had no clinical signs of central nervous system involvement and normal brain CT/MRI scan. Cognitive function was assessed on two consecutive days in 3 conditions: on day 1, while sitting, by means of a comprehensive battery of neuropsychological tests; on day 2, while tilted (HUT) and during supine rest (supine) in a randomized manner. BP and heart rate (HR) were continuously recorded non-invasively for the whole duration of the examination.

Results

patients with PAF or AAN displayed a preserved global cognitive function while sitting. However, compared to supine assessment, during HUT patients scored significantly worse during the Trail Making Test A and B, Barrage test, Analogies test, Immediate Visual Memory, Span Forward and Span Backward test. Pathological scores, with regard to Italian normative range values, were observed only during HUT in the Barrage test and in the Analogies test in 3 and 6 patients respectively. On the contrary, in healthy controls, results to neuropsychological tests were not significantly different, during HUT compared to supine rest.

Conclusions

these data demonstrate that patients with PAF and AAN present a normal sitting global cognitive evaluation. However, their executive functions worsen significantly during the orthostatic challenge, possibly because of transient frontal lobes hypoperfusion.

Syncope and orthostatic intolerance increase risk of brain lesions in migraineurs and controls

OBJECTIVES

We and others showed that migraineurs are at increased risk of subclinical and clinical ischemic brain lesions. Migraineurs also have a higher prevalence of frequent syncope and orthostatic intolerance, symptoms that are associated with transient reductions in cerebral blood flow. In this study, we assessed whether these autonomic symptoms may contribute to the increased risk of brain lesions in migraine.

METHODS

Migraineurs (n = 291) and controls (n = 140) from the population-based, cross-sectional CAMERA (Cerebral Abnormalities in Migraine, an Epidemiologic Risk Analysis) cohort (aged 30-60 years, and free of other neurologic symptoms) underwent 1) brain MRI scan, and 2) structured telephone interview including questions on frequent syncope (≥5/lifetime) and orthostatic intolerance.

RESULTS

Frequent syncope (odds ratio [OR] = 2.7; 95% confidence interval: 1.3-5.5) and orthostatic intolerance (OR = 2.0 [1.1-3.6]) were independent risk factors for high load of deep white matter lesions. Effects were strongest in women and similar in migraineurs and controls. Migraine diagnosis did not mediate or moderate these associations. Individuals with orthostatic intolerance had higher prevalence of high periventricular white matter lesion load (OR = 1.9 [1.1-3.5]). Syncope and orthostatic intolerance were not related to subclinical infarcts or infratentorial lesions.

CONCLUSIONS

Frequent syncope, orthostatic intolerance, and migraine independently increase the risk of white matter lesions, particularly in females.

Impact of blood pressure dysregulation on health-related quality of life in persons with spinal cord injury: development of a conceptual model

OBJECTIVES

To identify medically relevant aspects of blood pressure dysregulation (BPD) related to quality of life in individuals with spinal cord injury (SCI), and to propose an integrated conceptual framework based on input from both individuals with SCI and their clinical providers. This framework will serve as a guide for the development of a patient-reported outcome (PRO) measure specifically related to BPD.

DESIGN

Three focus groups with individuals with SCI and 3 groups with SCI providers were analyzed using grounded-theory based qualitative analysis to ascertain how blood pressure impacts health-related quality of life (HRQOL) in individuals with SCI.

SETTING

Focus groups were conducted at 2 Veterans Affairs medical centers and a research center.

PARTICIPANTS

Individuals with SCI (n=27) in 3 focus groups and clinical providers (n=25) in 3 focus groups.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Not applicable.

RESULTS

Qualitative analysis indicated that all focus groups spent the highest percentage of time discussing symptoms of BPD (39%), followed by precipitators/causes of BPD (16%), preventative actions (15%), corrective actions (12%), and the impact that BPD has on social or emotional functioning (8%). While patient/consumer focus groups and provider focus groups raised similar issues, providers spent more time discussing precipitators/causes of BPD and preventative actions (38%) than patient/consumer groups (24%).

CONCLUSIONS

These results suggest that BPD uniquely and adversely impacts HRQOL in persons with SCI. While both individuals with SCI and their providers highlighted the relevant symptoms of BPD, the SCI providers offered additional detailed information regarding the precipitators/causes and what can be done to prevent/treat BPD. Further, the results suggest that persons with SCI are aware of how BPD impacts their HRQOL and are able to distinguish between subtle signs and symptoms. These findings exemplify the need for a validated and sensitive clinical measurement tool that can assess the extent to which BPD impacts HRQOL in patients with SCI.

Neurogenic orthostatic hypotension: pathophysiology, evaluation, and management

Neurogenic orthostatic hypotension is a distinctive and treatable sign of cardiovascular autonomic dysfunction. It is caused by failure of noradrenergic neurotransmission that is associated with a range of primary or secondary autonomic disorders, including pure autonomic failure, Parkinson’s disease with autonomic failure, multiple system atrophy as well as diabetic and nondiabetic autonomic neuropathies. Neurogenic orthostatic hypotension is commonly accompanied by autonomic dysregulation involving other organ systems such as the bowel and the bladder. In the present review, we provide an overview of the clinical presentation, pathophysiology, epidemiology, evaluation and management of neurogenic orthostatic hypotension focusing on neurodegenerative disorders.

The potential prognostic role of cardiovascular autonomic failure in α-synucleinopathies

Cardiovascular autonomic failure is the second most common dysautonomic feature of α-synucleinopathies and has significant impact on daily activities and quality of life. Here we provide a systematic review of cardiovascular autonomic failure in α-synucleinopathies, emphasizing its impact on cognitive functions and disease outcomes. Articles spanning the period between January 1985 and April 2012 were identified from the PubMed database using a keyword-based search. Epidemiological studies highlight the negative prognostic effect of cardiovascular autonomic failure on cardiovascular and cerebrovascular outcomes and overall mortality in all α-synucleinopathies. Altered cerebral perfusion, vascular pressure stress, and related disruption of the blood-brain barrier may also contribute to the white matter hyperintensities and cognitive dysfunction frequently found in patients affected by neurocardiovascular instability. These findings support the hypothesis that cardiovascular autonomic failure may play a negative prognostic role in α-synucleinopathies and suggest that precocious screening and therapeutic management of cardiovascular autonomic failure may positively impact disease course.

Rapid eye movement sleep behavior disorder and subtypes of Parkinson's disease

Numerous studies have explored the potential relationship between rapid eye movement sleep behavior disorder (RBD) and manifestations of PD. Our aim was to perform an expanded extensive assessment of motor and nonmotor manifestations in PD to identify whether RBD was associated with differences in the nature and severity of these manifestations. PD patients underwent polysomnography (PSG) to diagnose the presence of RBD. Participants then underwent an extensive evaluation by a movement disorders specialist blinded to PSG results. Measures of disease severity, quantitative motor indices, motor subtypes, therapy complications, and autonomic, psychiatric, visual, and olfactory dysfunction were assessed and compared using regression analysis, adjusting for disease duration, age, and sex. Of 98 included patients, 54 had RBD and 44 did not. PD patients with RBD were older (P = 0.034) and were more likely to be male (P < 0.001). On regression analysis, the most consistent links between RBD and PD were a higher systolic blood pressure (BP) change while standing (-23.9 ± 13.9 versus -3.5 ± 10.9; P < 0.001), a higher orthostatic symptom score (0.89 ± 0.82 versus 0.44 ± 0.66; P = 0.003), and a higher frequency of freezing (43% versus 14%; P = 0.011). A systolic BP drop >10 could identify PD patients with RBD with 81% sensitivity and 86% specificity. In addition, there was a probable relationship between RBD and nontremor predominant subtype of PD (P = 0.04), increased frequency of falls (P = 0.009), and depression (P = 0.009). Our results support previous findings that RBD is a multifaceted phenomenon in PD. Patients with PD who have RBD tend to have specific motor and nonmotor manifestations, especially orthostatic hypotension.

Coat-hanger ache in orthostatic hypotension

Background

Questionnaires administered to orthostatic hypotension (OH) patients reveal frequent occurrence of coat-hanger ache (CHA), but laboratory-based precipitation of CHA during head-up tilt (HUT) has not been investigated. This study compared the frequency and clinical aspects of CHA in the same group of OH patients during daily activities versus during HUT.

Methods

Retrospective IRB-approved review of prospectively collected data on 22 dysautonomic patients. Heart rate response to deep breathing, Valsalva manoeuver, HUT and thermoregulatory sweat test evaluated cardiovagal, adrenergic and sudomotor functions. Occurrence and clinical features of CHA during daily activities and during HUT were recorded. Data were analysed with descriptive statistics.

Results

All patients demonstrated severe adrenergic (OH), cardiovagal and sudomotor impairment. Of 22 patients, 13 (59%) reported CHA within 3–5 minutes of standing or after 10 minutes to 2 hours of sitting that was relieved within 5–20 minutes of recumbency. During HUT, 4 of 13 (18%) patients developed CHA. Clinical features varied.

Conclusions

CHA was reported by 59% of OH patients during daily activities and by only 18% during HUT. The clinical characteristics of CHA episodes displayed inter-individual and intra-individual variability. These findings militate against direct association between OH and CHA and suggest a complex pathophysiology.