The Treatment of Primary Orthostatic Hypotension

Standing Blood Pressure and Risk of Falls, Syncope, Coronary Heart Disease, and Mortality

BACKGROUND

ACC/AHA guidelines caution against the use of antihypertensive therapy in the setting of low standing systolic BP (SBP) < 110 mm Hg due to unclear benefits.

METHODS

The Atherosclerosis Risk in Communities (ARIC) Study measured supine and standing SBP in adults aged 45-64 years between 1987 and 1989. We used Cox regression to evaluate the associations of low standing SBP (<110 mm Hg) with risk of falls, syncope, coronary heart disease (CHD), and mortality through December 31, 2019. Falls and syncope were ascertained by hospitalization and outpatient claims; CHD events were adjudicated. Associations were examined overall and in strata of hypertension stage, 10-year atherosclerotic cardiovascular disease (ASCVD) risk, age, and sex.

RESULTS

Among 12,467 adults followed a median of 24 years (mean age at enrollment 54.1 ± 5.8 years, 55% women, 26% Black adults), 3,000 (24%) had a standing SBP < 110 mm Hg. A standing SBP < 110 mm Hg compared to standing SBP ≥ 110 mm Hg was not significantly associated with falls or syncope, and was associated with a lower risk of CHD events and mortality with HRs of 1.02 (95% CI 0.94, 1.11), 1.02 (0.93, 1.11), 0.88 (0.80, 0.97), and 0.91 (0.86, 0.97), respectively. There were no clinically meaningful differences when stratified by hypertension stage, 10-year ASCVD risk, age, and sex.

CONCLUSIONS

In this community-based population, low standing SBP was common and not significantly associated with falls or syncope, but was associated with a lower risk of CHD and mortality. These findings do not support screening for low standing BP as a risk factor for adverse events.

The Effect of a Biofeedback-Based Integrated Program on Improving Orthostatic Hypotension in Community-Dwelling Older Adults: A Pilot Study

BACKGROUND

Orthostatic hypotension (OH) is prevalent among community-dwelling older adults and is associated with multiple negative health outcomes. Older adults are susceptible to developing OH because aging alters autonomic nervous system function. Biofeedback is a noninvasive, nonpharmacological intervention that can modulate autonomic nervous system dysfunction in older adults.

OBJECTIVES

Our aim in this study was to examine the effect of a biofeedback-based integrated program on community-dwelling older adults with OH.

METHODS

We conducted a controlled pilot study. Community-dwelling older adults 65 years or older who had nonneurogenic OH were eligible. Data from 51 participants, comprising 27 in the intervention group and 24 in the control group, were analyzed. Weekly biofeedback-based integrated program consisting of biofeedback training along with group education about behavioral modification, physical activities, and telephone counseling was provided for 12 weeks. Orthostatic hypotension was evaluated by measuring the drop in systolic and diastolic blood pressure after postural changes. Autonomic nervous system function was measured using heart rate variability.

RESULTS

Among the indicators of heart rate variability, total power (P = .037) and low frequency (P = .017) increased significantly, suggesting that autonomic function improved. Severity of orthostatic symptoms (P < .001) and drops in systolic (P = .003) and diastolic (P = .012) blood pressure after postural changes decreased significantly in the intervention group.

CONCLUSION

Biofeedback-based integrated program was effective in improving autonomic nervous system function and alleviated OH. Therefore, biofeedback-based integrated program should be tested in a larger randomized controlled study with long-term follow-up.

Sex-specific improvement in cardiac phenotype in older females combining blood withdrawal and exercise training

This study determined whether an intervention combining hematological and exercise stimuli may overcome the prevailing limitations to improve the cardiac phenotype and orthostatic tolerance (OT) of females with advanced age. Healthy females (n = 15) and males (n = 14) matched by age (63.7 ± 7.0 vs. 63.6 ± 8.7 yr) and moderate physical activity were recruited. OT, transthoracic echocardiography, and central hemodynamics were assessed during incremental lower body negative pressure (LBNP) levels (up to -50 mmHg) for 1 h or until presyncope, prior to and after an intervention comprising standard (10%) blood withdrawal and an 8-wk exercise training program designed to maximize central hemodynamic adaptations. OT time was lower in females compared with males (48.1 ± 10.6 vs. 57.0 ± 4.8 min, P = 0.008) before the intervention. Improved OT time (+11%) in females (48.1 ± 10.6 vs. 53.5 ± 6.1 min, P = 0.021) but not in males (57.0 ± 4.8 vs. 56.7 ± 5.6 min, P = 0.868) was found following the intervention, resulting in similar OT time between females and males (P = 0.156). The intervention induced improvements in left ventricular (LV) diastolic function (+13% for myocardial e') along with increased LV mass (+13%) in females (P ≤ 0.039) but not in males (P ≥ 0.257). During the initial LBNP stages (0 to -20 mmHg), LV stroke volume and cardiac output were exclusively increased in females after the intervention (P ≤ 0.034). In conclusion, the cardiac phenotype of females with advanced age can be structurally and functionally modified in parallel to improved OT via short-term hematological and central hemodynamic stimuli.NEW & NOTEWORTHY Based on previous studies, main features of the cardiac phenotype in females with advanced age are generally unresponsive to lifestyle interventions. The present findings reveals that the cardiac phenotype of middle-age and older females is amenable to large modification in a short-term period when hematological stimuli are combined with those induced by exercise training. The same intervention only induced minor adaptations in males matched by age and potential confounding factors.

Beta Blockers can mask not only Hypoglycemia, but also Hypotension

Background:

Beta-adrenergic (β-AR) receptor blockers (BBs) are an essential class of drugs as they have numerous indications. On the other hand, they have numerous unwanted effects which decrease the compliance, adherence, and persistence of this very useful group of drugs.

Objective:

The paper aims to analyze the possibility that an unnoticed side effect may contribute to a less favorable pharmacologic profile of BBs, e.g., a diminished reaction to a sudden fall in BP.

Methods:

We searched two medical databases for abstracts and citations (Medline and SCOPUS). Moreover, we searched the internet for drug prescription leaflets (of the individual BBs).

Results:

Whichever cause of stress is considered, the somatic manifestations of stress will be (partially) masked if a patient takes BB. Stress–induced hypercatecholaminemia acts on β-AR of cardiomyocytes; it increases heart rate and contractility, effects suppressed by BBs. The answers of the organism to hypoglycemia and hypotension share the main mechanisms such as sympathetic nervous system activation and hypercatecholaminemia. Thus, there is a striking analogy: BBs can cover up symptoms of both hypoglycemia (which is widely known) and of hypotension (which is not recognized). It is widely known that BBs can cause hypotension. However, they can also complicate recovery by spoiling the defense mechanisms in hypotension as they interfere with the crucial compensatory reflex to increase blood pressure in hypotension.

Conclusion:

Beta blockers can cause hypotension, mask it, and make recovery more difficult. This is clinically important and deserves to be more investigated and probably to be stated as a warning.

Treatment strategies for clozapine-induced hypotension: a systematic review

BACKGROUND

Clozapine is the most effective medication for treatment-refractory schizophrenia but is associated with significant adverse drug effects, including hypotension and dizziness, which have a negative impact on quality of life and treatment compliance. Available evidence for the management of clozapine-induced hypotension is scant.

OBJECTIVES

Due to limited guidance on the safety and efficacy of pharmacological treatments for clozapine-induced hypotension, we set out to systematically review and assess the evidence for the management of clozapine-induced hypotension and provide guidance to clinicians, patients, and carers.

DESIGN

We undertook a systematic review of the safety and efficacy of interventions for clozapine-induced hypotension given the limited available evidence.

DATA SOURCES AND METHODS

PubMed, Embase, PsycINFO, CINAHL, and the Cochrane trial Registry were searched from inception to November 2021 for literature on the treatment strategies for clozapine-induced hypotension and dizziness using a PROSPERO pre-registered search strategy. For orthostatic hypotension, we developed a management framework to assist in the choice of intervention.

RESULTS

We identified nine case studies and four case series describing interventions in 15 patients. Hypotension interventions included temporary clozapine dose reduction, non-pharmacological treatments, and pharmacological treatments. Midodrine, fludrocortisone, moclobemide and Bovril^® combination, and etilefrine were associated with improvement in symptoms or reduction in orthostatic hypotension. Angiotensin II, arginine vasopressin, and noradrenaline successfully restored and maintained mean arterial pressure in critical care situations. A paradoxical reaction of severe hypotension was reported with adrenaline use.

CONCLUSION

Orthostatic hypotension is a common side effect during clozapine titration. Following an assessment of the titration schedule, salt and fluid intake, and review of hypertensive and nonselective α1-adrenergic agents, first-line treatment should be a temporary reduction in clozapine dose or non-pharmacological interventions. If orthostatic hypotension persists, fludrocortisone should be trialled with monitoring of potassium levels and sodium and fluid intake. Midodrine may be considered second-line or where fludrocortisone is contraindicated or poorly tolerated. For patients on clozapine with hypotension in critical care settings, the use of adrenaline to maintain mean arterial pressure should be avoided.

REGISTRATION

PROSPERO (Registration No. CRD42020191530).

Effect of using elastic-pressure socks in spinal surgery patients on orthostatic hypotension in the first mobilization

BACKGROUND

Orthostatic hypotension (OH) is a common early postoperative finding in patients who undergo major surgery, and it might delay early mobilization, which is the main building block of modern perioperative care programs. The aim of this study was to determine the effect of using thigh-length elastic pressure socks in patients who undergo spinal surgery in development of OH at first mobilization after surgery.

METHODS

The study was a randomized-controlled intervention study. A total of 70 patients who underwent spinal surgery were included in the study. The patients were allocated randomly to the intervention group (n = 35) who used thigh-length elastic pressure socks and the control group (n = 35) which received no intervention other than routine nursing care.

RESULTS

It was found in the study that 2.9% of the patients in the intervention group developed OH during the first mobilization after the surgery, and 48.6% of the patients in the control group developed OH at first mobilization. The patients in the intervention group were found to have the risk ratio (RR): 0.06 times less probability of developing OH than the patients in the control group (95% confidence interval [CI]:0.01-0.42). The OH symptoms were lower in the patients in the intervention group.

CONCLUSION

It was found as a result of the study that using thigh-length elastic pressure socks in spinal surgery patients reduced OH development and symptoms at first mobilization after the surgery.

Clinical Prognostic Factors in Pediatric Patients With Orthostatic Intolerance

Midodrine is widely used for orthostatic intolerance (OI); however, little is known about the prognostic factors of OI after midodrine treatment. We retrospectively reviewed electronic medical charts to investigate clinical prognostic factors of OI on 159 OI patients aged 7 to 18 years who were treated with midodrine at a children's hospital. Logistic regression was conducted to clarify predictors for improving symptoms at the first month of the treatment. Patients with orthostatic uncomfortable feeling or fainting were significantly more likely to improve symptoms at the first month of the treatment (odds ratio [OR], 3.48; 95% confidence interval [95%CI], 1.36-8.89), but patients with underweight were significantly less likely to improve symptoms (OR, 0.19; 95%CI, 0.06-0.56). Our results suggest that predictive factors for OI by midodrine treatments are orthostatic symptoms and underweight in pediatric patients. These findings are useful to develop further studies for OI treatments.

Drug-Related Orthostatic Hypotension: Beyond Anti-Hypertensive Medications

Orthostatic hypotension (OH) is an abnormal blood pressure response to standing, which is associated with an increased risk of adverse outcomes such as syncope, falls, cognitive impairment, and mortality. Medical therapy is one the most common causes of OH, since numerous cardiovascular and psychoactive medications may interfere with the blood pressure response to standing, leading to drug-related OH. Additionally, hypotensive medications frequently overlap with other OH risk factors (e.g., advanced age, neurogenic autonomic dysfunction, and comorbidities), thus increasing the risk of symptoms and complications. Consequently, a medication review is recommended as a first-line approach in the diagnostic and therapeutic work-up of OH, with a view to minimizing the risk of drug-related orthostatic blood pressure impairment. If symptoms persist after the review of hypotensive medications, despite adherence to non-pharmacological interventions, specific drug treatment for OH can be considered. In this narrative review we present an overview of drugs acting on the cardiovascular and central nervous system that may potentially impair the orthostatic blood pressure response and we provide practical suggestions that may be helpful to guide medical therapy optimization in patients with OH. In addition, we summarize the available strategies for drug treatment of OH in patients with persistent symptoms despite non-pharmacological interventions.

Orthostatic hypotension and health-related quality of life among community-living older people in Korea

PURPOSE

To investigate the association of orthostatic hypotension (OH) with health-related quality of life (HRQoL) in older people living in the community.

METHODS

A cross-sectional design was used. A total of 217 participants aged 65 and older were classified as having OH if their systolic or diastolic blood pressure showed a drop of ≥ 20 mmHg systolic blood pressure or ≥ 10 mmHg diastolic blood pressure, respectively, within 3 min of standing. Participants provided demographic and medical information and responded to questionnaires about their HRQoL (EuroQoL-5D-3L), as well as depression, anxiety, cognitive function, and recent physical activities.

RESULTS

The number of participants with OH was 117, and those without OH numbered 100. The mean HRQoL levels were 0.56 (SD 0.29) in the OH group and 0.74 (SD 0.25) in the non-OH group (p < .001). Participants with OH were more likely to be older, women, and smokers. These participants had fewer years of education, a greater history of stroke and hypertension, and a greater number of comorbidities. The absence of OH, a higher physical activity level, a lower degree of depression, an absence of stroke history, and younger age were all significant determinants of greater HRQoL.

CONCLUSIONS

The level of HRQoL of older people with OH was significantly lower than that of older people without. The presence of OH was an independent determinant of HRQoL in older adults after adjusting for covariates. This finding suggests that strategies for relieving OH could improve HRQoL in affected older adults.

Nonpharmacologic Management of Orthostatic Hypotension in Older People: A Systematic Review. The SENATOR ONTOP Series

OBJECTIVES

Nonpharmacologic therapies are often recommended as a first-line treatment for orthostatic hypotension (OH). However, the true effect of nonpharmacologic therapy remains unclear, particularly in the older population. We undertook a systematic review evaluating the efficacy of nonpharmacologic interventions in older people with OH to provide evidence-based recommendations.

DESIGN

Systematic review of systematic reviews.

SETTING AND PARTICIPANTS

MEDLINE, PubMed, EMBASE, and Cochrane Database of Systematic Reviews, CINHAL, and PsycINFO were searched up to June 2018. Two reviewers identified eligible systematic reviews from which primary studies were selected. We included both randomized and nonrandomized studies that evaluated any type of nonpharmacologic intervention and reported outcomes of change in postural drop in systolic blood pressure (SBP) and/or orthostatic symptoms measured using any validated instrument. The Cochrane risk of bias tool was used, with recommendations based on the GRADE approach.

RESULTS

Eleven trials were included. Meta-analysis of lower limb compression showed a reduction in the postural drop in SBP of 9.83 mmHg [95% confidence interval (CI) -12.56, -7.11], whereas abdominal compression showed a larger reduction in postural drop in SBP of 12.30 mmHg (95% CI -18.20, -6.39). Compression therapy was also beneficial in reducing OH symptoms. However, the quality of the evidence for compression therapy was very poor. One study each was identified for sleeping with head-up (SHU), home-based resistance training (HBRT), and multicomponent intervention but did not significantly reduce postural SBP drop. Bolus water drinking was effective in 1 study but the study was of low quality.

CONCLUSIONS/IMPLICATIONS

There is no high-quality evidence to recommend any of the nonpharmacologic therapies for the management of OH in older people. Yet, we make a weak recommendation for lower limb and abdominal compression therapy based on very low quality evidence. Large-scale trials are warranted in older people to substantiate the efficacy of nonpharmacologic therapies in OH.

[Hypotensions in the elderly: Clinical and therapeutic features]

Hypotension and especially very low diastolic blood pressure could be an at-risk situation in very old and frail patients and in those with coronary heart disease. Chronic hypotension in people with heart failure is an indicator of poor prognosis and hinders the management of therapy. Orthostatic hypotension is a decrease in blood pressure>20mmHg for systolic and/or>10mmHg for diastolic within 3minutes after transition from supine to upright. Orthostatic hypotension may be symptomatic or not. The search for orthostatic hypotension is part of the clinical examination of elderly patients with hypertension, falling, diabetes and or polymedication. First intention treatment aims to correct modifiable modifying factors and to limit the circulatory consequences of orthostatism by elastic venous compression.

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.

Management of Orthostatic Hypotension: A Literature Review

In the older population, especially the hospitalized patients who are prone to dehydration and hypovolemia, orthostatic hypotension (OH) presents as a debilitating disease. How different pharmacological and non-pharmacological interventions affect the incapacitating symptoms (falls and episodes of syncope), morbidity, and mortality related to OH has become a topic of debate. OH can predispose to ischemic heart disease (IHD). A non-pharmacological approach consisting of mobilization, early lifestyle changes, and therapeutic maneuvers is the first choice in the management of these patients. Individuals with persistent symptoms require pharmaceutical therapy to increase blood volume and peripheral vascular resistance. This article summarizes the management of OH that is vital to cope with the needs of the growing geriatric populations.

Orthostatic hypotension for the cardiologist

PURPOSE OF REVIEW

Orthostatic hypotension is a phenomenon commonly encountered in a cardiologist's clinical practice that has significant diagnostic and prognostic value for a cardiologist. Given the mounting evidence associating cardiovascular morbidity and mortality with orthostatic hypotension, cardiologists will play an increasing role in treating and managing patients with orthostatic hypotension.

RECENT FINDINGS

The American College of Cardiology, American Heart Association, and Heart Rhythm Society recently published consensus guidelines on the diagnosis, treatment, and management of syncope and their instigators, including orthostatic hypotension. Additionally, consensus guidelines have also been recently updated, reinforcing the universal definition orthostatic hypotension and its closely associated pathologies. Finally, the United States Food and Drug Administration (FDA) recently approved droxidopa, a synthetic oral norepinephrine prodrug, in 2014 for the treatment of neurogenic orthostatic hypotension (nOH), and it represents a well tolerated, effective, and easy to use intervention for nOH. This represents only the second drug approved by the FDA for orthostatic hypotension, the first being midodrine in 1986. A handful of smaller head-to-head studies have pitted not only pharmacologic agents to one another but also nonpharmacologic interventions to pharmacologic agents. Additionally, recent studies have also reported on more convenient screening tools for orthostatic hypotension.

SUMMARY

Though there have been many advances in the management of orthostatic hypotension, nOH remains a chronic, debilitating, and often progressively fatal condition. Cardiologists can play a very important role in optimizing hemodynamics in this patient population to improve quality of life and minimize cardiovascular risk.

Autonomic Dysfunction in Cardiology: Pathophysiology, Investigation, and Management

Presyncope and syncope are common medical findings, with a > 40% estimated lifetime prevalence. These conditions are often elicited by postural stress and can be recurrent and accompanied by debilitating symptoms of cerebral hypoperfusion. Therefore, it is critical for physicians to become familiar with the diagnosis and treatment of common underlying causes of presyncope and syncope. In some patients, altered postural hemodynamic responses result from a failure of compensatory autonomic nervous system reflex mechanisms. The most common presentations of presyncope and syncope secondary to this autonomic dysfunction include vasovagal syncope, neurogenic orthostatic hypotension, and postural tachycardia syndrome. The most sensitive method for diagnosis is a detailed initial evaluation with medical history, physical examination, and resting electrocardiogram to rule out cardiac syncope. Physical examination should include measurement of supine and standing blood pressure and heart rate to identify the pattern of hemodynamic regulation during orthostatic stress. Additional testing may be required in patients without a clear diagnosis after the initial evaluation. Management of patients should focus on improving symptoms and functional status and not targeting arbitrary hemodynamic values. An individualized structured and stepwise approach should be taken for treatment, starting with patient education, lifestyle modifications, and use of physical counter-pressure manoeuvres and devices to improve venous return. Pharmacologic interventions should be added only when conservative approaches are insufficient to improve symptoms. There are no gold standard approaches for pharmacologic treatment in these conditions, with medications often used off label and with limited long-term data for effectiveness.

Chemogenetic locus coeruleus activation restores reversal learning in a rat model of Alzheimer's disease

See Grinberg and Heinsen (doi:10.1093/brain/awx261) for a scientific commentary on this article. Clinical evidence suggests that aberrant tau accumulation in the locus coeruleus and noradrenergic dysfunction may be a critical early step in Alzheimer’s disease progression. Yet, an accurate preclinical model of these phenotypes that includes early pretangle tau accrual in the locus coeruleus, loss of locus coeruleus innervation and deficits locus coeruleus/norepinephrine modulated behaviours, does not exist, hampering the identification of underlying mechanisms and the development of locus coeruleus-based therapies. Here, a transgenic rat (TgF344-AD) expressing disease-causing mutant amyloid precursor protein (APPsw) and presenilin-1 (PS1ΔE9) was characterized for histological and behavioural signs of locus coeruleus dysfunction reminiscent of mild cognitive impairment/early Alzheimer’s disease. In TgF344-AD rats, hyperphosphorylated tau was detected in the locus coeruleus prior to accrual in the medial entorhinal cortex or hippocampus, and tau pathology in the locus coeruleus was negatively correlated with noradrenergic innervation in the medial entorhinal cortex. Likewise, TgF344-AD rats displayed progressive loss of hippocampal norepinephrine levels and locus coeruleus fibres in the medial entorhinal cortex and dentate gyrus, with no frank noradrenergic cell body loss. Cultured mouse locus coeruleus neurons expressing hyperphosphorylation-prone mutant human tau had shorter neurites than control neurons, but similar cell viability, suggesting a causal link between pretangle tau accrual and altered locus coeruleus fibre morphology. TgF344-AD rats had impaired reversal learning in the Morris water maze compared to their wild-type littermates, which was rescued by chemogenetic locus coeruleus activation via designer receptors exclusively activated by designer drugs (DREADDs). Our results indicate that TgF344-AD rats uniquely meet several key criteria for a suitable model of locus coeruleus pathology and dysfunction early in Alzheimer’s disease progression, and suggest that a substantial window of opportunity for locus coeruleus/ norepinephrine-based therapeutics exists.