Management of Orthostatic Hypotension, Postprandial Hypotension, and Supine Hypertension

Atomoxetine on neurogenic orthostatic hypotension: a randomized, double-blind, placebo-controlled crossover trial

PURPOSE

We previously reported that single doses of the norepinephrine transporter inhibitor, atomoxetine, increased standing blood pressure (BP) and ameliorated symptoms in patients with neurogenic orthostatic hypotension (nOH). We aimed to evaluate the effect of atomoxetine over four weeks in patients with nOH.

METHODS

A randomized, double-blind, placebo-controlled crossover clinical trial between July 2016 and May 2021 was carried out with an initial open-label, single-dose phase (10 or 18 mg atomoxetine), followed by a 1-week wash-out, and a subsequent double-blind 4-week treatment sequence (period 1: atomoxetine followed by placebo) or vice versa (period 2). The trial included a 2-week wash-out period. The primary endpoint was symptoms of nOH as measured by the orthostatic hypotension questionnaire (OHQ) assessed at 2 weeks.

RESULTS

A total of 68 patients were screened, 40 were randomized, and 37 completed the study. We found no differences in the OHQ composite score between atomoxetine and placebo at 2 weeks (-0.3 ± 1.7 versus -0.4 ± 1.5; P = 0.806) and 4 weeks (-0.6 ± 2.4 versus -0.5 ± 1.6; P = 0.251). There were no differences either in the OHSA scores at 2 weeks (3 ± 1.9 versus 4 ± 2.1; P = 0.062) and at 4 weeks (3 ± 2.2 versus 3 ± 2.0; P = 1.000) or in the OH daily activity scores (OHDAS) at 2 weeks (4 ± 3.0 versus 5 ± 3.1, P = 0.102) and 4 weeks (4 ± 3.0 versus 4 ± 2.7, P = 0.095). Atomoxetine was well-tolerated.

CONCLUSIONS

While previous evidence suggested that acute doses of atomoxetine might be efficacious in treating nOH; results of this clinical trial indicated that it was not superior to placebo to ameliorate symptoms of nOH.

TRIAL REGISTRATION

ClinicalTrials.gov; NCT02316821.

Effect of orthostatic hypotension on long-term prognosis of elderly patients with stable coronary artery disease: a retrospective cohort study

Background

The long-term prognosis of patients with stable coronary artery disease (CAD) combined with orthostatic hypotension (OH) has rarely been reported. This research was designed to examine whether OH increases the risk of all-cause mortality and cardiovascular death among patients with stable CAD.

Methods

We retrospectively analyzed retired military personnel over 65 years of age who were hospitalized at the General Hospital of Southern Theater Command of the Chinese People's Liberation Army between March and July 2010. A total of 924 patients with stable CAD were included, among whom 263 had OH. The risk of all-cause mortality and cardiovascular death in OH and non-OH groups were analyzed with the Cox proportional hazards models, and restricted cubic spline plots were utilized for subgroup analyses. Furthermore, competing risk models were applied for sensitivity analyses.

Results

The median age of the patients was 82.00 (80.00-85.00) years. Over 159 months of follow-up, the loss to follow-up rate was 2.27%, and all-cause mortality was observed in 574 (63.57%) patients, including 184 with OH. Moreover, cardiovascular death occurred in 127 patients (13.73%), with 58 cases associated with OH. Although the relationship between OH and all-cause mortality was non-significant [body mass index (BMI) < 25 group, adjusted hazard ratio (HR) = 1.10 with a 95% confidence interval (CI): 0.82-1.40; BMI ≥ 25 group, adjusted HR = 1.30, 95% CI: 0.98-1.70], it was independently related to a growing risk of cardiovascular death (adjusted HR = 1.80, 95% CI: 1.20-2.60). This finding was further validated by using a competing risk model (subdistribution HR = 1.74, 95% CI: 1.22-2.49). Moreover, age, low-density lipoprotein cholesterol, and frequency of hospital admissions were identified as risk factors of cardiovascular death among patients with OH (P < 0.05).

Conclusion

Our study, based on retired military personnel with stable CAD, found that OH led to a significantly higher risk of cardiovascular death, but it was not noticeably associated with all-cause mortality on long-term prognosis.

Sympathetic dysfunction as an early indicator of autonomic involvement in Parkinson's disease

PURPOSE

The specific characteristics of autonomic involvement in patients with early Parkinson's disease (PD) are unclear. This study aimed to evaluate the characteristics of autonomic dysfunction in drug-naïve patients with early-stage PD without orthostatic hypotension (OH) by analyzing Valsalva maneuver (VM) parameters.

METHODS

We retrospectively analyzed drug-naïve patients without orthostatic hypotension (n = 61) and controls (n = 20). The patients were subcategorized into early PD (n = 35) and mid-PD (n = 26) groups on the basis of the Hoehn and Yahr staging. VM parameters, including changes in systolic blood pressure at late phase 2 (∆SBPVM2), ∆HRVM3, Valsalva ratio (VR), pressure recovery time, adrenergic baroreflex sensitivity, and vagal baroreflex sensitivity, were assessed.

RESULTS

In the early PD group, ∆SBPVM2, a marker of sympathetic function, was significantly lower compared with that in controls (risk ratio = 0.95, P = 0.027). Receiver operating characteristic (ROC) curve analysis showed an optimal cut-off value of -10 mmHg for ∆SBPVM2 [P = 0.002, area under the curve (AUC): 0.737]. VR exhibited an inverse relationship with Unified Parkinson's Disease Rating Scale Part 3 scores in the multivariable regression analysis (VR: P = 0.038, β = -28.61), whereas age showed a positive relationship (age: P = 0.027, β = 0.35).

CONCLUSION

The ∆BPVM2 parameter of the VM may help detect autonomic nervous system involvement in early-PD without OH. Our results suggest that sympathetic dysfunction is an early manifestation of autonomic dysfunction in patients with PD.

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.

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.

Postprandial Hypotension: An Underreported Silent Killer in the Aged

Orthostatic hypotension (OH) is one of the most common autonomic dysfunctions, with high prevalence in populations of elderly, hypertensive, diabetic, or Parkinson's patients. Evidence is emerging that OH co-occurs with postprandial hypotension (PPH); a greater prevalence of PPH than of OH is reported for Parkinson's disease patients. OH is diagnosed by measuring the blood pressure changes associated with postural changes and often produces alterations in consciousness or other such bothersome symptoms as fainting. PPH is diagnosed by measuring the blood pressure changes associated with ingesting high carbohydrate test meals. Because of the time lag between food ingestion and absorption, PPH is often not reported as symptomatic and, therefore, not diagnosed as PPH. OH and PPH are independent predictors for all causes of mortality. Relative underdiagnosis may qualify PPH as a "silent killer" disease. This review is aimed at providing updates on the epidemiology, pathophysiology, and clinical aspects associated with the diagnosis and treatment of PPH. Highlighting the current gaps in knowledge and research about PPH is expected to make medical practitioners more cognizant of the dangers of underdiagnosis and motivate future research to identify individuals and populations at high risk for PPH and its sequelae.

Synucleinopathies

The α-synucleinopathies include pure autonomic failure, multiple system atrophy, dementia with Lewy bodies, and Parkinson disease. The past two decades have witnessed significant advances in the diagnostic strategies and symptomatic treatment of motor and nonmotor symptoms of the synucleinopathies. This chapter provides an in-depth review of the pathophysiology, pathology, genetic, epidemiology, and clinical and laboratory autonomic features that distinguish the different synucleinopathies with an emphasis on autonomic failure as a common feature. The treatment of the different synucleinopathies is discussed along with the proposal for multidisciplinary, individualized care models that optimally address the various symptoms. There is an urgent need for clinical scientific studies addressing patients at risk of developing synucleinopathies and the investigation of disease mechanisms, biomarkers, potential disease-modifying therapies, and further advancement of symptomatic treatments for motor and nonmotor symptoms.

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.

Orthostatic Hypotension: Management of a Complex, But Common, Medical Problem

Orthostatic hypotension (OH), a common, often overlooked, disorder with many causes, is associated with debilitating symptoms, falls, syncope, cognitive impairment, and risk of death. Chronic OH, a cardinal sign of autonomic dysfunction, increases with advancing age and is commonly associated with neurodegenerative and autoimmune diseases, diabetes, hypertension, heart failure, and kidney failure. Management typically involves a multidisciplinary, patient-centered, approach to arrive at an appropriate underlying diagnosis that is causing OH, treating accompanying conditions, and providing individually tailored pharmacological and nonpharmacological treatment. We propose a novel streamlined pathophysiological classification of OH; review the relationship between the cardiovascular disease continuum and OH; discuss OH-mediated end-organ damage; provide diagnostic and therapeutic algorithms to guide clinical decision making and patient care; identify current gaps in knowledge and try to define future research directions. Using a case-based learning approach, specific clinical scenarios are presented highlighting various presentations of OH to provide a practical guide to evaluate and manage patients who have OH.

Management of Orthostatic Hypotension in the Hospitalized Patient: A Narrative Review

Orthostatic hypotension is a frequent cause of falls and syncope, impairing quality of life. It is an independent risk factor of mortality and a common cause of hospitalizations, which exponentially increases in the geriatric population. We present a management plan based on a systematic literature review and understanding of the underlying pathophysiology and relevant clinical pharmacology. Initial treatment measures include removing offending medications and avoiding large meals. Clinical assessment of the patients' residual sympathetic tone can aid in the selection of initial therapy between norepinephrine "enhancers" or "replacers." Role of splanchnic venous pooling is overlooked, and applying abdominal binders to improve venous return may be effective. The treatment goal is not normalizing upright blood pressure but increasing it above the cerebral autoregulation threshold required to improve symptoms. Hypertension is the most common associated comorbidity, and confining patients to bed while using pressor agents only increases supine blood pressure, leading to worsening pressure diuresis and orthostatic hypotension. Avoiding bedrest deconditioning and using pressors as part of an orthostatic rehab program are crucial in reducing hospital stay.

Effect of ingesting a meal and orthostasis on the regulation of splanchnic and systemic hemodynamics and the responsiveness of cardiovascular α1-adrenoceptors

Postprandial orthostasis activates mechanisms of cardiovascular homeostasis to maintain normal blood pressure (BP) and adequate blood flow to vital organs. The underlying mechanisms of cardiovascular homeostasis in postprandial orthostasis still require elucidation. Fourteen healthy volunteers were recruited to investigate the effect of an orthostatic challenge (60°-head-up-tilt for 20 min) on splanchnic and systemic hemodynamics before and after ingesting an 800-kcal composite meal. The splanchnic circulation was assessed by ultrasonography of the superior mesenteric and hepatic arteries and portal vein. Systemic hemodynamics were assessed noninvasively by continuous monitoring of BP, heart rate (HR), cardiac output (CO), and the pressor response to an intravenous infusion on increasing doses of phenylephrine, an α₁-adrenoceptor agonist. Neurohumoral regulation was assessed by spectral analysis of HR and BP, plasma catecholamine and aldosterone levels and plasma renin activity. Postprandial mesenteric hyperemia was associated with an increase in CO, a decrease in SVR and cardiac vagal tone, and reduction in baroreflex sensitivity with no change in sympathetic tone. Arterial α₁-adrenoceptor responsiveness was preserved and reduced in hepatic sinusoids. Postprandial orthostasis was associated with a shift of 500 mL of blood from mesenteric to systemic circulation with preserved sympathetic-mediated vasoconstriction. Meal ingestion provokes cardiovascular hyperdynamism, cardiac vagolysis, and resetting of the baroreflex without activation of the sympathetic nervous system. Meal ingestion also alters α₁-adrenoceptor responsiveness in the hepatic sinusoids and participates in the redistribution of blood volume from the mesenteric to the systemic circulation to maintain a normal BP during orthostasis.NEW & NOTEWORTHY A unique integrated investigation on the effect of meal on neurohumoral mechanisms and blood flow redistribution of the mesenteric circulation during orthostasis was investigated. Food ingestion results in cardiovascular hyperdynamism, reduction in cardiac vagal tone, and baroreflex sensitivity and causes a decrease in α₁-adrenoceptor responsiveness only in the venous intrahepatic sinusoids. About 500-mL blood shifts from the mesenteric to the systemic circulation during orthostasis. Accordingly, the orthostatic homeostatic mechanisms are better understood.

Safety and efficacy of ampreloxetine in symptomatic neurogenic orthostatic hypotension: a phase 2 trial

PURPOSE

In neurogenic orthostatic hypotension, blood pressure falls when upright owing to impaired release of norepinephrine, leading to dizziness. Ampreloxetine, a selective norepinephrine reuptake inhibitor, increases circulating norepinephrine levels. This study explored the safety of ampreloxetine and its effect on blood pressure and symptoms in patients with neurogenic orthostatic hypotension.

METHODS

A multicenter ascending-dose trial (range 1-20 mg, Part A) was followed by a 1 day, double-blind, randomized, placebo-controlled study (median dose 15 mg, Part B). Eligible patients then enrolled in a 20-week, open-label, steady-state extension phase (median dose 10 mg, Part C) followed by a 4-week withdrawal. Assessments included the Orthostatic Hypotension Symptom Assessment Scale (item 1), supine/seated/standing blood pressure, and safety.

RESULTS

Thirty-four patients (age 66 ± 8 years, 22 men) were enrolled. Part A: The proportion of participants with a positive response (i.e., increase from baseline in seated systolic blood pressure of ≥ 10 mmHg) was greater with the 5 and 10 mg ampreloxetine doses than with placebo or other active ampreloxetine doses. Part B: Seated blood pressure increased 15.7 mmHg 4 h after ampreloxetine and decreased 14.2 mmHg after placebo [least squares mean difference (95% CI) 29.9 mmHg (7.6-52.3); P = 0.0112]. Part C: Symptoms of dizziness/lightheadedness improved 3.1 ± 3.0 points from baseline and standing systolic blood pressure increased 11 ± 12 mmHg. After 4 weeks of withdrawal, symptoms returned to pretreatment levels. The effect of ampreloxetine on supine blood pressure was minimal throughout treatment duration.

CONCLUSION

Ampreloxetine was well tolerated and improved orthostatic symptoms and seated/standing blood pressure with little change in supine blood pressure.

TRIAL REGISTRATION

NCT02705755 (first posted March 10, 2016).