Midodrine for orthostatic hypotension: a systematic review and meta-analysis of clinical trials

A therapeutic challenge relating to the association of orthostatic hypotension and supine hypertension in a patient with cardiac autonomic neuropathy: a case report

BACKGROUND

Cardiac autonomic neuropathy is a highly prevalent pathology in the diabetic population, and is the leading cause of death in this population. Orthostatic hypotension is the main clinical manifestation of the disease. In some patients, this orthostatic hypotension is associated with supine hypertension, posing a therapeutic challenge since treatment of one entity may aggravate the other. The challenge is to manage each of these two hemodynamic opposites without exposing the patient to a life-threatening risk of severe hypotension or hypertension.

CASE PRESENTATION

We report a case of a 62-year-old ethnic Moroccan woman who has cardiovascular risk factors such as type 2 diabetes, arterial hypertension, and dyslipidemia. The patient's symptoms included dizziness, tremors, morning sickness, palpitations, and intolerance to exertion. Given her symptomatology, the patient benefited from an exploration of the autonomic nervous system through cardiovascular reactivity tests (Ewing tests), which confirmed the diagnosis of cardiac autonomic neuropathy. In addition to orthostatic hypotension, our patient had supine arterial hypertension, complicating management. To treat orthostatic hypotension, we advised the patient to avoid the supine position during the day, to raise the head of the bed during the night, and to have a sufficient fluid intake, with a gradual transition from decubitus to orthostatism and venous restraint of the lower limbs. Supine hypertension was treated with transdermal nitrates placed at bedtime and removed 1 hour before getting up. One week after the introduction of treatment, the patient reported a clear regression of functional symptoms, with an improvement in her quality of life. Improvement in symptomatology was maintained during quarterly follow-up consultations.

CONCLUSIONS

Cardiac autonomic neuropathy is a very common pathology in diabetic patients. It is a serious condition with a life-threatening prognosis. Its management must be individualized according to the symptomatology and profile of each patient. The treatment of patients with orthostatic hypotension and supine hypertension requires special attention to ensure that each entity is treated without aggravating the other.

Midodrine-Induced Nightmares in the Treatment of Orthostatic Hypotension: A Case Report

Background Midodrine was the first medication approved by the Food and Drug Administration (FDA) for the treatment of orthostatic hypotension. Pharmacologically, midodrine is a peripheral selective alpha-1-adrenergic agonist that can improve standing, sitting, and supine systolic blood pressure. Common side effects include bradycardia, supine hypertension, and paresthesia. A novel side effect of midodrine-induced nightmares has been reported in our patient. To our knowledge, this is the first reported case of midodrine-induced nightmares. Objective To investigate and report a clinically significant and unique drug adverse event of midodrine in the treatment of orthostatic hypotension. Case Presentation This report describes a case of persistent nightmares associated with midodrine use in an 83-year-old male who experienced frequent syncope episodes treated with midodrine for orthostatic hypotension (OH). After the initiation of midodrine, the patient complained of increased nightmares, which quickly led to his refusal of the medication, despite the initial improvements in his blood pressure. The timing of administration included an evening dose at 21:00. This novel adverse event of midodrine-induced nightmares will be highlighted and explored in this case report. Conclusion This case demonstrated a unique adverse event of nightmares caused by midodrine. It is hypothesized that autonomic dysfunction plays a role and further investigations should be conducted to confirm this theory. We hope that our case report highlights the importance of careful consideration when prescribing midodrine in older people with orthostatic hypotension.

An update review on hemodynamic instability in renal replacement therapy patients

BACKGROUND

Hemodynamic instability in patients undergoing kidney replacement therapy (KRT) is one of the most common and essential factors influencing mortality, morbidity, and the quality of life in this patient population.

METHOD

Decreased cardiac preload, reduced systemic vascular resistance, redistribution of fluids, fluid overload, inflammatory factors, and changes in plasma osmolality have all been implicated in the pathophysiology of hemodynamic instability associated with KRT.

RESULT

A cascade of these detrimental mechanisms may ultimately cause intra-dialytic hypotension, reduced tissue perfusion, and impaired kidney rehabilitation. Multiple parameters, including dialysate composition, temperature, posture during dialysis sessions, physical activity, fluid administrations, dialysis timing, and specific pharmacologic agents, have been studied as possible management modalities. Nevertheless, a clear consensus is not reached.

CONCLUSION

This review includes a thorough investigation of the literature on hemodynamic instability in KRT patients, providing insight on interventions that may potentially minimize factors leading to hemodynamic instability.

Orthostatic Hypotension in Multiple System Atrophy: Related Factors and Disease Prognosis

BACKGROUND

Multiple system atrophy (MSA) is a rare neurodegenerative disease characterized by Parkinsonism, ataxia, and autonomic nervous failure. Orthostatic hypotension (OH) is the main feature of central vascular autonomic failure in MSA.

OBJECTIVE

The study aimed elucidate the effects of OH on cognitive function, disease milestones, and survival.

METHODS

A total of 444 patients with clinically established MSA were enrolled. Mild and severe OH were defined as a decrease in systolic blood pressure (SBP)/diastolic blood pressure (DBP) >20/10 mmHg and SBP/DBP ≥30/15 mmHg, respectively.

RESULTS

In this study, 215 MSA patients presented without OH, 88 had mild OH, and 141 had severe OH. The proportion of MSA-C in the severe OH subgroup was significantly higher than that in the subgroup without OH (95/46 vs. 113/102, p = 0.021). The UMSARS I score and the frequency of supine hypertension (SH) in patients with OH were significantly higher than those in patients without OH (16.22 vs. 16.89 vs. 14.60, p < 0.001; 77/64 vs. 29/59 vs. 32/183, p < 0.001). Factors related to the severity of OH included sex (OR, 0.65; p = 0.031), onset age (OR, 0.98; p = 0.029), and SH (OR, 0.21; p < 0.001). The median survival time of patients with severe OH was significantly lower than that of patients without OH (6.79 vs. 8.13 years, p = 0.001). Consistently, Cox survival analysis found that compared with patients without OH, patients with severe OH had a significantly increased risk of death (OR, 2.22; p < 0.001).

CONCLUSION

Our large cohort study of MSA provides additional evidence for the negative impact of severe OH on survival.

Midodrine use in critically ill patients: a narrative review

Midodrine is a peripherally acting, oral α-agonist that is increasingly used in intensive care units despite conflicting evidence for its effectiveness. It has pharmacological effects on blood vessels as well as pupillary, cardiac, renal, gastrointestinal, genitourinary, lymphatic and skin tissue. It has approval for use as a treatment for orthostatic hypotension, but a surge in interest over the past decade has prompted its use for a growing number of off-label indications. In critically ill patients, midodrine has been used as either an adjunctive oral therapy to wean vasoplegic patients off low dose intravenous vasopressor infusions, or as an oral vasopressor agent to prevent or minimise the need for intravenous infusion. Clinical trials have mostly focused on midodrine as an intravenous vasopressor weaning agent. Early retrospective studies supported its use for this indication, but more recent randomised controlled trials have largely refuted this practice. Key questions remain on its role in managing critically ill patients before intensive care admission, during intensive care stay, and following discharge. This narrative review presents a comprehensive overview of midodrine use for the critical care physician and highlights why lingering questions around ideal patient selection, dosing, timing of initiation, and efficacy of midodrine for critically ill patients remain unanswered.

Midodrine to optimize heart failure therapy in patients with concurrent hypotension

According to the Centers for Disease Control and Prevention statistics, about 6.2 million adults in the United States have heart failure. Guideline-Directed Medical Therapy (GDMT) involving the use of renin-angiotensin-aldosterone system inhibitors with or without a neprilysin inhibitor, β-blockers, mineralocorticoid-receptor-antagonists, and sodium-glucose cotransporter-2 inhibitors serve as the backbone for heart failure with reduced ejection fraction (HFrEF) therapy. However, in patients with refractory hypotension, the initiation of GDMT may not be possible. We present four cases where the use of midodrine, an alpha adrenergic agonist, serves as bridge therapy for the initiation or continuation of GDMT with marked clinical improvement. These cases illustrate how exacerbations of HFrEF may be ameliorated with outpatient midodrine titration among patients with baseline, persistent hypotension such that GDMT may be better tolerated.

A pilot, feasibility, randomised controlled trial of midodrine as adjunctive vasopressor for low-dose vasopressor-dependent hypotension in intensive care patients: The MAVERIC study

PURPOSE

To assess the feasibility and physiological efficacy of adjunctive midodrine in patients with vasopressor-dependent hypotension.

MATERIALS AND METHODS

This was a pilot, open label, randomised controlled trial. Patients were enrolled from two tertiary intensive care units on low dose intravenous vasopressor therapy for more than 24 h. We randomly assigned patients to receive either adjunctive midodrine (10 mg every 8 h) or usual care. The primary efficacy outcome was time to cessation of intravenous vasopressor therapy. Secondary outcomes included protocol compliance, ICU and hospital length of stay.

RESULTS

We screened 381 patients over 22-months and enrolled 62 (32 in midodrine group, 30 in usual care group). Median time to cessation of vasopressor infusion was 16.5 h for midodrine vs 19 h for usual care (p = 0.22). Time in ICU (50 [25.50, 74.00] hours for midodrine v 59 [38.50, 93.25] hours for usual care, p = 0.14) and hospital length of stay (9 days vs. 7.5 days, p = 0.92) were similar. Protocol compliance was 96.9%. One patient ceased midodrine early due to symptomatic bradycardia.

CONCLUSIONS

Adjunctive midodrine therapy was feasible with acceptable compliance, duration of therapy, and safety profile. However, at the chosen dose, there was no evidence of physiological or clinical efficacy.

Ambulatory blood pressure and drug treatment for orthostatic hypotension as predictors of mortality in patients with Multiple System Atrophy

OBJECTIVES

Multiple system atrophy (MSA) is a rare fatal neurodegenerative disease characterized by parkinsonism, cerebellar ataxia and autonomic failure. This study aimed at investigating possible associations between mortality, 24H blood pressure (BP) level and variability, and drug treatments for orthostatic hypotension (OH) in MSA patients.

METHODS

One hundred and twenty-nine patients followed at the French Reference Center for MSA who underwent routine 24H ambulatory BP monitoring, were included. Unified MSA Rating Scale (UMSARS) scores, drug treatments and the occurrence and cause of death were recorded.

RESULTS

Seventy patients died during follow-up (2.9±1.8 years), mainly from terminal illness, pulmonary or sudden death. Multivariate Cox regression analysis, after adjustment for gender, disease duration and severity (UMSARS I+II score), showed that increased daytime systolic BP variability, OH severity and OH drug treatment were independently correlated with mortality. OH treatment was associated with the risk of cardiac causes and/or sudden death (p=0.01). In a fully adjusted model, male gender [(female vs male) Hazard ratio (HR): 0.56 95% CI [0.34-0.94] p=0.03], UMSARS I+II score [HR: 1.04 95% CI [1.02-1.06] p<0.01], systolic BP daytime variability [HR: 3.66 95% CI (1.46-9.17 p<0.01] and OH treatment [HR: 2.13 95 % CI [1.15- 3.94]; p=0.02] predicted mortality.

CONCLUSION

Increased daytime BP variability and OH treatment were predictive of mortality in patients with MSA, independently from disease severity. Further studies are required to assess if these associations are explained by more severe autonomic dysfunction or if OH treatment exposes "per se" to a specific risk in this population.

Management of Hypertension and Blood Pressure Dysregulation in Patients with Parkinson's Disease-a Systematic Review

PURPOSE OF REVIEW

The aim of this review article was to summarize the cardiovascular and blood pressure profile regarding Parkinson disease patients and to provide an update on the recent advancements in the field of the diagnosis and management of blood pressure abnormalities in these patients. Our goal was to guide physicians to avoid pitfalls in current practice while treating patients with Parkinson disease and blood pressure abnormalities. For this purpose, we searched bibliographic databases (PubMed, Google Scholar) for all publications published on blood pressure effects in Parkinson disease until May 2020. Furthermore, we highlight some thoughts and potential perspectives for the next possible steps in the field.

RECENT FINDINGS

Blood pressure dysregulation in patients with Parkinson's disease has several implications in clinical practice and presents an ongoing concern. Compared with chronic essential hypertension, the syndrome of combined neurogenic orthostatic hypotension and supine hypertension in Parkinson's disease has received little attention. If left untreated, hypertension may lead to cardiovascular disease whereas hypotension may lead to fall-related complications, with tremendous impact on the quality of life of affected individuals. The effect of blood Epressure control and the risk of death from cardiovascular disease in Parkinson disease are largely unexplored. Blood pressure abnormalities in Parkinson disease present bidirectional relationship and the rationale for treating and controlling hypertension in persons with Parkinson disease and concurrent neurogenic orthostatic hypotension and/or supine hypertension is compelling. Further research is warranted in order to clarify the mechanisms, clinical implications, and potential reversibility of compromised cardiovascular function, in persons with Parkinson disease.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Cardiovascular Disorders Mediated by Autonomic Nervous System Dysfunction

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

Cardiovascular Safety Considerations in the Treatment of Neurogenic Orthostatic Hypotension

Neurogenic orthostatic hypotension (nOH), a drop in blood pressure upon standing resulting from autonomic malfunction, may cause debilitating symptoms that can affect independence in daily activities and quality-of-life. nOH may also be associated with cardiovascular comorbidities (e.g., supine hypertension, heart failure, diabetes, and arrhythmias), making treatment decisions complicated and requiring management that should be based on a patient's cardiovascular profile. Additionally, drugs used to treat the cardiovascular disorders (e.g., vasodilators, β-blockers) can exacerbate nOH and concomitant symptoms. When orthostatic symptoms are severe and not effectively managed with nonpharmacologic strategies (e.g., water ingestion, abdominal compression), droxidopa or midodrine may be effective. Droxidopa may be less likely than midodrine to exacerbate supine hypertension, based on conclusions of a limited meta-analysis. In conclusion, treating nOH in patients with cardiovascular conditions requires a balance between symptom relief and minimizing adverse outcomes.

Efficacy of atomoxetine versus midodrine for neurogenic orthostatic hypotension

Objective

The efficacy and safety of 1‐month atomoxetine and midodrine therapies were compared. Three‐month atomoxetine and combination therapies were investigated for additional benefits.

Methods

This prospective open‐label randomized trial included 50 patients with symptomatic neurogenic orthostatic hypotension (nOH). The patients received either atomoxetine 18 mg daily or midodrine 5 mg twice daily and were evaluated 1 and 3 months later. Those who still met the criteria for nOH at 1 month received both midodrine and atomoxetine for an additional 2 months, and if not, they continued their initial medication. The primary outcome was an improvement in orthostatic blood pressure (BP) drop (maximum BP change from supine to 3 min after standing) at 1 month. The secondary endpoints were symptom scores, percentage of patients with nOH at 1 and 3 months.

Results

Patients with midodrine or atomoxetine treatment showed comparative improvement in the orthostatic BP drop, and overall only 26.2% of the patients had nOH at 1 month, which was similar between the treatment groups. Only atomoxetine resulted in significant symptomatic improvements at 1 month. For those without nOH at 1 month, there was additional symptomatic improvement at 3 months with their initial medication. For those with nOH at 1 month, the combination treatment resulted in no additional improvement. Mild‐to‐moderate adverse events were reported by 11.6% of the patients.

Interpretation

One‐month atomoxetine treatment was effective and safe in nOH patients. Atomoxetine improved orthostatic BP changes as much as midodrine and was better in terms of ameliorating nOH symptoms.

Cardiac Autonomic Neuropathy in Obesity, the Metabolic Syndrome and Prediabetes: A Narrative Review

Cardiac autonomic neuropathy (CAN) is a major complication of type 1 and type 2 diabetes mellitus (T1DM and T2DM). The increased morbidity, cardiovascular and all-cause mortality associated with CAN is established from numerous epidemiological studies. However, CAN is increasingly recognised in people with prediabetes (pre-DM) and the metabolic syndrome (MetS) with a reported prevalence up to 11% and 24% respectively. CAN is associated with components of MetS including hypertension and obesity, predating hyperglycaemia. The aetiology of CAN is multifactorial and there is a reciprocal relationship with insulin resistance and MetS. Obstructive sleep apnoea (OSA) is also associated with CAN possibly through MetS and an independent mechanism. An estimated global prevalence of the impaired glucose tolerance (IGT) form of pre-DM of 587 million people by 2045 means CAN will become a major clinical problem. CAN is independently associated with silent myocardial ischaemia, major cardiovascular events, myocardial dysfunction and cardiovascular mortality. Screening for CAN in pre-DM using risk scores with analysis of heart rate variability (HRV) or Sudoscan is important to allow earlier treatment at a reversible stage. The link between obesity and CAN highlights the therapeutic potential of lifestyle interventions including diet and physical activity to reverse MetS and prevent CAN. Weight loss achieved using these dietary and exercise lifestyle interventions improves the sympathetic and parasympathetic HRV indices of cardiac autonomic function. Further research is needed to identify high-risk populations of people with pre-DM or obesity that might benefit from targeted pharmacotherapy including metformin, sodium/glucose cotransporter 2 (SGLT2) inhibitors and glucagon-like peptide 1 (GLP-1) analogues. Bariatric surgery also improves HRV through weight loss which might also prevent CAN in severe obesity. This article reviews the literature on CAN in obesity, pre-DM and MetS, to help determine a rationale for screening, early intervention treatment and formulate future research questions in this highly prevalent condition.

Diagnosis and Management of Autonomic Dysfunction in Dementia Syndromes

PURPOSE OF REVIEW

Autonomic dysfunction is common in dementia, particularly in the Lewy body dementias. This review considers the evidence for autonomic dysfunction in dementia, common symptoms and potential management options.

RECENT FINDINGS

Autonomic dysfunction has been shown in Alzheimer's disease and Lewy body dementias. Common symptoms include orthostatic dizziness, syncope, falls, urinary tract symptoms and constipation. Non-pharmacological management of orthostatic hypotension should include bolus water drinking. Pharmacological management may include the use of midodrine or droxidopa although the latter is not available in Europe. Atomoxetine is a noradrenaline reuptake inhibitor which may be useful if further clinical trials become available. Management of constipation may include the use o f probiotics, osmotic laxatives such as macrogol and chloride type 2 channel activators such as lubiprostone. Management of urinary tract symptoms may include the use of mirabegron. There is a dearth of clinical trials for autonomic dysfunction in dementia and most of the evidence is imputed from trials in Parkinson's disease. However, pragmatic recommendations may be made. There is a need for controlled clinical trials in people with dementia.

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.

Autonomic dysfunction: Diagnosis and management

The autonomic nervous system is designed to maintain physiologic homeostasis. Its widespread connections make it vulnerable to disruption by many disease processes including primary etiologies such as Parkinson's disease, multiple system atrophy, dementia with Lewy bodies, and pure autonomic failure and secondary etiologies such as diabetes mellitus, amyloidosis, and immune-mediated illnesses. The result is numerous symptoms involving the cardiovascular, gastrointestinal, and urogenital systems. Patients with autonomic dysfunction (AUD) often have peripheral and/or cardiac denervation leading to impairment of the baroreflex, which is known to play a major role in determining hemodynamic outcome during orthostatic stress and low cardiac output states. Heart rate and plasma norepinephrine responses to orthostatic stress are helpful in diagnosing impairment of the baroreflex in patients with orthostatic hypotension (OH) and suspected AUD. Similarly, cardiac sympathetic denervation diagnosed with MIBG scintigraphy or ¹⁸F-DA PET scanning has also been shown to be helpful in distinguishing preganglionic from postganglionic involvement and in diagnosing early stages of neurodegenerative diseases. In this chapter, we review the causes of AUD, the pathophysiology and resulting cardiovascular manifestations with emphasis on the diagnosis and treatment of OH.

Acceptability of non-drug therapies in older people with orthostatic hypotension: a qualitative study

Background

Orthostatic hypotension (OH) is highly prevalent in older populations. It is associated with a reduced quality of life and an increased risk of dementia, stroke and death. Non-pharmalogical therapies are the recommended first-line therapy and are preferred to drug treatments by older people. However, uptake and adherence is low and evidence for their use is lacking. Objective: Determine the acceptability of non-pharmalogical interventions for OH in older people.

Methods

This qualitative study, nested within a phase II efficacy study, recruited 25 people aged over 60 years from a Falls and Syncope Clinic. All participants had experienced the following non-pharmalogical therapies within a phase II study: bolus water drinking, compression stockings, abdominal compression, physical counter-manoeuvres. Individual semi-structured qualitative interviews were recorded and transcribed verbatim. Emergent themes were identified through framework analysis of transcripts.

Results

Physical counter-manoeuvres were considered the most acceptable therapy as no equipment is required, they can be performed discreetly and are only required during postural change. Bolus water drinking was mostly considered as an acceptable therapy, although there were significant concerns around urinary frequency. The idea of bolus water drinking was a barrier to its uptake, but once experienced it was easier than anticipated. Participants had mixed views on acceptability of abdominal compression whereas compression stockings were considered unacceptable by the majority of participants. This was due to the practicalities of applying/removing the compression and the stigma attached to their appearance.

Conclusions

Current first-line treatment with compression stockings is largely unacceptable to older people with OH, challenging current guidelines. In order to promote uptake and adherence, first line therapy should focus on bolus-water drinking and physical counter-manoeuvres.

Patient Selection for Kidney Transplant

The incidence of end-stage renal disease has continued to increase. Similarly, the number of patients living with a functioning renal allograft has also increased. Transplantation has improved with advances in surgical techniques, immunosuppression, and better control of comorbid conditions. Transplantation is transformative and offers the greatest potential for restoring a healthy, productive, and durable life to appropriately selected patients. This article describes factors to address in selection of renal transplant candidates and discusses commonly encountered perioperative events. Paramount to selecting appropriate candidates is the collaboration between a multidisciplinary team focused on a systematic process guided by protocols and common practices.

Standing and Supine Blood Pressure Outcomes Associated With Droxidopa and Midodrine in Patients With Neurogenic Orthostatic Hypotension: A Bayesian Meta-analysis and Mixed Treatment Comparison of Randomized Trials

BACKGROUND

The comparative effects of droxidopa and midodrine on standing systolic blood pressure (sSBP) and risk of supine hypertension in patients with neurogenic orthostatic hypotension (NOH) are unknown.

OBJECTIVE

To perform a Bayesian mixed-treatment comparison meta-analysis of droxidopa and midodrine in the treatment of NOH.

METHODS

The PubMed, CENTRAL, and EMBASE databases were searched up to November 16, 2016. Study selection consisted of randomized trials comparing droxidopa or midodrine with placebo and reporting on changes in sSBP and supine hypertension events. Data were pooled to perform a comparison among interventions in a Bayesian fixed-effects model using vague priors and Markov chain Monte Carlo simulation with Gibbs sampling, calculating pooled mean changes in sSBP and risk ratios (RRs) for supine hypertension with associated 95% credible intervals (CrIs).

RESULTS

Six studies (4 administering droxidopa and 2 administering midodrine) enrolling a total of 783 patients were included for analysis. The mean change from baseline in sSBP was significantly greater for both drugs when compared with placebo (droxidopa 6.2 mm Hg [95% CrI = 2.4-10] and midodrine 17 mm Hg [95% CrI = 11.4-23]). Comparative analysis revealed a significant credible difference between droxidopa and midodrine. The RR for supine hypertension was significantly greater for midodrine, but not droxidopa, when compared with placebo (droxidopa RR = 1.4 [95% CrI = 0.7-2.7] and midodrine RR = 5.1 [95% CrI = 1.6-24]). Conclusion and Relevance: In patients with NOH, both droxidopa and midodrine significantly increase sSBP, the latter to a greater extent. However, midodrine, but not droxidopa, significantly increases risk of supine hypertension.

Hemodynamic Instability during Dialysis: The Potential Role of Intradialytic Exercise

Acute haemodynamic instability is a natural consequence of disordered cardiovascular physiology during haemodialysis (HD). Prevalence of intradialytic hypotension (IDH) can be as high as 20–30%, contributing to subclinical, transient myocardial ischemia. In the long term, this results in progressive, maladaptive cardiac remodeling and impairment of left ventricular function. This is thought to be a major contributor to increased cardiovascular mortality in end stage renal disease (ESRD). Medical strategies to acutely attenuate haemodynamic instability during HD are suboptimal. Whilst a programme of intradialytic exercise training appears to facilitate numerous chronic adaptations, little is known of the acute physiological response to this type of exercise. In particular, the potential for intradialytic exercise to acutely stabilise cardiovascular hemodynamics, thus preventing IDH and myocardial ischemia, has not been explored. This narrative review aims to summarise the characteristics and causes of acute haemodynamic instability during HD, with an overview of current medical therapies to treat IDH. Moreover, we discuss the acute physiological response to intradialytic exercise with a view to determining the potential for this nonmedical intervention to stabilise cardiovascular haemodynamics during HD, improve coronary perfusion, and reduce cardiovascular morbidity and mortality in ESRD.

Orthostatic hypotension: pathophysiology, assessment, treatment and the paradox of supine hypertension

Both hypertension and orthostatic hypotension (OH) are strongly age-associated and are common management problems in older people. However, unlike hypertension, management of OH has unique challenges with few well-established treatments. Not infrequently, they both coexist, further compounding the management. This review provides comprehensive information on OH, including pathophysiology, diagnostic workup and treatment, with a view to provide a practical guide to its management. Special references are made to patients with supine hypertension and postprandial hypotension and older hypertensive patients.

Effectiveness of droxidopa compared to midodrine in standing blood pressure and orthostatic tolerance in adults with neurogenic orthostatic hypotension: a systematic review protocol

REVIEW QUESTION

The question of this review is: what is the effectiveness of droxidopa compared to midodrine on standing blood pressure and orthostatic intolerance symptoms in adults with neurogenic orthostatic hypotension?

Efficacy of single or combined midodrine and pyridostigmine in orthostatic hypotension

OBJECTIVE

To evaluate the long-term (for up to 3 months) efficacy and safety of single or combined therapy with midodrine and pyridostigmine for neurogenic orthostatic hypotension (OH).

METHODS

This was a randomized, open-label clinical trial. In total, 87 patients with symptomatic neurogenic OH were enrolled and randomized to receive 1 of 3 treatments: midodrine only, pyridostigmine only, or midodrine + pyridostigmine. The patients were followed up at 1 and 3 months after treatment. The primary outcome measures were improvement in orthostatic blood pressure (BP) drop at 3 months. Secondary endpoints were improvement of the orthostatic BP drop at 1 month and amelioration of the questionnaire score evaluating OH-associated symptoms.

RESULTS

Orthostatic systolic and diastolic BP drops improved significantly at 3 months after treatment in all treatment groups. Orthostatic symptoms were significantly ameliorated during the 3-month treatment, and the symptom severity was as follows: midodrine only < midodrine + pyridostigmine < pyridostigmine only group. Mild to moderate adverse events were reported by 11.5% of the patients.

CONCLUSIONS

Single or combination treatment with midodrine and pyridostigmine was effective and safe in patients with OH for up to 3 months. Midodrine was better than pyridostigmine at improving OH-related symptoms.

CLINICALTRIALSGOV IDENTIFIER

NCT02308124.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that for patients with neurogenic OH, long-term treatment with midodrine alone, pyridostigmine alone, or both midodrine and pyridostigmine is safe and has similar effects in improving orthostatic BP drop up to 3 months.

Integrated analysis of droxidopa trials for neurogenic orthostatic hypotension

Background

Droxidopa, a prodrug of norepinephrine, was approved for treatment of neurogenic orthostatic hypotension (nOH) due to primary autonomic disorders based on 3 randomized double-blind studies. We performed safety and efficacy analyses of this pooled dataset (n = 460).

Methods

Efficacy was assessed using Orthostatic Hypotension Questionnaire (OHQ) scores (composite and individual items). Safety and tolerability were also examined.

Results

Droxidopa improved virtually all nOH symptom scores compared with placebo, significantly reducing OHQ composite score (−2.68 ± 2.20 vs −1.82 ± 2.34 units; P < 0.001), dizziness/lightheadedness score (−3.0 ± 2.9 vs −1.8 ± 3.1 units; P < 0.001), and 3 of 5 other symptom assessments (visual disturbances, weakness, and fatigue [P ≤ 0.010]). Droxidopa significantly improved 3 of 4 measures of activities of daily living (standing a long time, walking a short time, and walking a long time [P ≤ 0.003]) and significantly increased upright systolic blood pressure (11.5 ± 20.5 vs 4.8 ± 21.0 mmHg for placebo; P < 0.001). Droxidopa was effective in patients using inhibitors of dopa decarboxylase (DDCI; the enzyme that converts droxidopa to norepinephrine), but its efficacy was numerically greater in non-DDCI users. Droxidopa was well-tolerated. Rates of most adverse events were similar between groups. Supine hypertension rates were low, but slightly higher in patients receiving droxidopa (≤7.9% vs ≤4.6% for placebo); patients with severe hypertension at screening were excluded from these studies.

Conclusions

Droxidopa is effective for the treatment of nOH in patients with primary autonomic disorders and is generally well-tolerated. A longer trial is underway to confirm efficacy beyond the ≤2 to 10 - week period assessed in the current trials.

Trial registration

ClinicalTrials.gov identifiers: NCT00782340, first received October 29, 2008; NCT00633880, first received March 5, 2008; and NCT01176240, first received July 30, 2010.

The recommendations of a consensus panel for the screening, diagnosis, and treatment of neurogenic orthostatic hypotension and associated supine hypertension

Neurogenic orthostatic hypotension (nOH) is common in patients with neurodegenerative disorders such as Parkinson’s disease, multiple system atrophy, pure autonomic failure, dementia with Lewy bodies, and peripheral neuropathies including amyloid or diabetic neuropathy. Due to the frequency of nOH in the aging population, clinicians need to be well informed about its diagnosis and management. To date, studies of nOH have used different outcome measures and various methods of diagnosis, thereby preventing the generation of evidence-based guidelines to direct clinicians towards ‘best practices’ when treating patients with nOH and associated supine hypertension. To address these issues, the American Autonomic Society and the National Parkinson Foundation initiated a project to develop a statement of recommendations beginning with a consensus panel meeting in Boston on November 7, 2015, with continued communications and contributions to the recommendations through October of 2016. This paper summarizes the panel members’ discussions held during the initial meeting along with continued deliberations among the panel members and provides essential recommendations based upon best available evidence as well as expert opinion for the (1) screening, (2) diagnosis, (3) treatment of nOH, and (4) diagnosis and treatment of associated supine hypertension.

Taste and Smell Disturbance Resulting From Midodrine

Objective:

To report a case of dysgeusia and dysosmia following midodrine initiation.

Methods/Case Summary:

A 58-year-old male started midodrine 5 mg tablets 3 times a day for orthostatic hypotension. Two weeks after starting, he began complaining of dysgeusia and dysosmia. He also reported less of an appetite at this time but did not realize it was due to symptoms. He reported his symptoms as tolerable and chose to continue the medicine. At follow-up contact 7 days later, the symptoms were still present but diminishing.

Main results/Discussion:

Midodrine is used for symptoms of orthostatic hypotension. Dysgeusia and dysosmia are not common adverse events and are not included in the manufacturer’s labeling. There is only one other published case report of this reaction. Our patient only admitted to slight appetite suppression, but it may be more profound in some. The reaction may be dose related, but there is not enough information to make this conclusion.

Principal conclusions:

Using midodrine may result in dysgeusia and dysosmia. According to this case, both adverse effects may lessen or resolve over time with the use of the medication.

Midodrine for severe orthostatic hypotension

Midodrine (Bramox-Brancaster Pharma Limited) was authorised in the UK by the Medicines and Healthcare products Regulatory Agency (MHRA) in March 2015 for "the treatment of severe orthostatic hypotension due to autonomic dysfunction in adults when corrective factors have been ruled out and other forms of treatment are inadequate".(1) Previously, midodrine had only been available in the UK as an unlicensed product used on a named-patient basis. It is the first drug to be licensed in the UK for the treatment of orthostatic hypotension. Here we consider the evidence for midodrine in the treatment of severe orthostatic hypotension and how it fits with current management strategies.

Cost-effectiveness of droxidopa in patients with neurogenic orthostatic hypotension: post-hoc economic analysis of Phase 3 clinical trial data

OBJECTIVE

Falls are associated with neurogenic orthostatic hypotension (nOH) and are an economic burden on the US healthcare system. Droxidopa is approved by the US FDA to treat symptomatic nOH. This study estimates the cost-effectiveness of droxidopa vs standard of care from a US payer perspective.

METHODS

A Markov model was used to predict numbers of falls and treatment responses using data from a randomized, double-blind trial of patients with Parkinson's disease and nOH who received optimized droxidopa therapy or placebo for 8 weeks. The severity of falls, utility values, and injury-related costs were derived from published studies. Model outcomes included number of falls, number of quality-adjusted life-years (QALYs), and direct costs. Incremental cost-effectiveness ratios (ICERs) were calculated. Outcomes were extrapolated over 12 months.

RESULTS

Patients receiving droxidopa had fewer falls compared with those receiving standard of care and gained 0.33 QALYs/patient. Estimated droxidopa costs were $30,112, with estimated cost savings resulting from fall avoidance of $14,574 over 12 months. Droxidopa was cost-effective vs standard of care, with ICERs of $47,001/QALY gained, $24,866 per avoided fall with moderate/major injury, and $1559 per avoided fall with no/minor injury. The main drivers were fall probabilities and fear of fall-related inputs.

LIMITATIONS

A limitation of the current study is the reliance on falls data from a randomized controlled trial where the placebo group served as the proxy for standard of care. Data from a larger patient population, reflecting 'real-life' patient use and/or comparison with other agents used to treat nOH, would have been a useful complement, but these data were not available.

CONCLUSION

Using Markov modeling, droxidopa appears to be a cost-effective option compared with standard of care in US clinical practice for the treatment of nOH.