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

OBJECTIVE: To evaluate the effects of droxidopa or atomoxetine on intravenous (IV) vasoactive agent discontinuation in cardiothoracic intensive care unit (ICU) patients with hypotension refractory to midodrine. DESIGN: Single-center, retrospective cohort study. SETTING: Tertiary- and quaternary-care university teaching hospital. PARTICIPANTS: Included patients who received at least 4 consecutive doses of droxidopa or atomoxetine and remained on concurrent midodrine. Patients were excluded if they received study medication before admission, had clinical deterioration after study medication initiation requiring additional vasoactives/escalation of IV vasoactive dosage for at least 12 hours, had a diagnosis of hepatorenal syndrome, were prisoners, or were pregnant. INTERVENTIONS: Droxidopa, atomoxetine, or both. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was time to discontinuation of IV vasoactive agents after initiation of study medication, analyzed using a Kaplan-Meier estimate with the Wilcoxon method, censoring death within 24 hours of the last dose of study medication. No adjustment for repetitive analyses was made, as the analysis was hypothesis-generating. Of the 72 charts reviewed, 45 patients met inclusion criteria (18 atomoxetine, 17 droxidopa, and 10 both). There were no differences in median time to discontinuation of IV vasoactive agents (21.9 days v 8.0 days v 13.9 days, respectively; p = 0.259) or ICU or hospital length of stay between groups. A higher percentage of patients who survived to hospital discharge received both study medications or droxidopa alone (90% v 76.5%) than atomoxetine alone (44.4%, p = 0.028). CONCLUSIONS: Droxidopa and atomoxetine are oral vasoactive agents with potential mechanisms to facilitate IV vasopressor weaning for patients in the ICU with hypotension refractory to midodrine, but further prospective research is needed.

Droxidopa (Northera®) en hipotensión ortostática neurogénica por enfermedad de Parkinson / Droxidopa (Northera®) in orthostatic hypotension neurogenic due to Parkinson's disease

INTRODUCCIÓN: La hipotensión ortostática (HO) es definida como una reducción de la presión arterial sistólica de al menos 20 mmHg o una reducción de la presión arterial diastólica de al menos 10 mmHg, generalmente dentro de los primeros tres minutos después de estar de pie o de inclinar la cabeza hacia arriba sobre una mesa inclinada.1 Muchos trastornos pueden causar HO, siendo los principales mecanismos la disfunción barorrefleja, la depleción grave de volumen y los eventos adversos de los medicamentos. La HO se define como sintomática cuando la persona experimenta mareos, aturdimiento, síncope, dolor muscular en el cuello y los hombros e incluso angina al pararse.2. La OH neurogénica ocurre por disfunción barorrefleja y las neuronas simpáticas posganglionares no liberan noradrenalina de forma adecuada. La presión arterial cae progresivamente después de estar de pie porque la acumulación gravitacional de sangre en las piernas no puede compensarse mediante vasoconstricción simpática. La liberación subnormal de norepinefrina produce vasoconstricción alterada y volumen vascular intratorácico reducido, los cuales contribuyen a la hipotensión ortostática. La disfunción autonómica, incluida la disfunción barorrefleja que causa HO neurogénica, es una característica clínica común de las sinucleinopatías, que se caracterizan patológicamente por inclusiones neuronales citoplasmáticas (cuerpos de Lewy) o gliales que contienen alfasinucleína que se encuentran en el cerebro y los nervios autónomos periféricos de las personas con enfermedad de Parkinson. La prevalencia de HO neurogénica aumenta con la edad y la duración de la enfermedad, estando presente entre el 20 y el 60 % de las personas con esta enfermedad. TECNOLOGÍA: La droxidopa, un análogo de aminoácido sintético que se metaboliza a norepinefrina y puede aumentar la presión arterial al causar vasoconstricción de las arterias y venas periféricas. Se han observado aumentos menores y temporales en los niveles plasmáticos de norepinefrina después de la administración de droxidopa. OBJETIVO: El objetivo del presente informe es evaluar rápidamente los parámetros de eficacia, seguridad, costos y recomendaciones disponibles acerca del empleo del uso de droxidopa (Northera®) en hipotensión ortostática neurogénica por enfermedad de Parkinson. MÉTODOS: Se realizó una búsqueda bibliográfica en las principales bases de datos tales como PUBMED, LILACS, BRISA, COCHRANE, SCIELO, EMBASE, TRIPDATABASE como así también en sociedades científicas, agencias reguladoras, financiadores de salud y agencias de evaluación de tecnologías sanitarias. Se priorizó la inclusión de revisiones sistemáticas, ensayos clínicos controlados aleatorizados, evaluación de tecnología sanitaria y guías de práctica clínica de alta calidad metodológica. EVIDENCIA CLÍNICA: Hauser y cols. publicaron en 2028 un análisis integrado de los estudios disponibles sobre droxidopa frente a placebo para el tratamiento de la HO neurogénica en adultos con enfermedad de Parkinson. 7 El análisis incluyó tres ensayos clínicos de fase III multicéntricos (NOH301, NOH302 y NOH306B) que evaluaron droxidopa en personas con HO neurogénica sintomática por enfermedad de Parkinson y otras causas. 8­10 Estos ensayos inicialmente aleatorizaron un total de 332 personas con enfermedad de Parkinson (droxidopa [n=171] o placebo [n=162]), sin embargo, 25 personas (n=21 para droxidopa y n=5 para placebo) interrumpieron el tratamiento antes de las primeras mediciones de resultados y no se incluyeron en los análisis de eficacia. RECOMENDACIONES: No se hallaron recomendaciones para Argentina o Latinoamérica sobre la tecnología en la indicación evaluada. La Sociedad Internacional de Parkinson y Trastornos del Movimiento en 2019 menciona, entre otros medicamentos, que la droxidopa es posiblemente una opción de tratamiento para la HO neurogénica. 15 Las fundaciones de Parkinson para Estados Unidos y Canadá no la mencionan. El medicamento no ha sido evaluado, y por lo tanto no es cubierto, por la Agencia Canadiense de Medicamentos y Tecnologías en Salud (CADTH, su sigla del inglés Canadian Agency for Drugs and Technologies in Health) y el Plan de Beneficios Farmacéuticos (PBS, su sigla del inglés Pharmaceutical Benefits Scheme) de Australia. CONCLUSIONES: La evidencia que sustenta la aprobación de comercialización por parte de los Estados Unidos de droxidopa (Northera®) en adultos con hipotensión ortostática neurogénica sintomática se basa en tres ensayos clínicos aleatorizados de fase III. Cabe señalar que la agencia estadounidense la ha autorizado en 2014, mientras que la Agencia Europea de Medicamentos aún no lo ha hecho. Estos estudios demostraron que en pocas personas con hipotensión ortostática moderada por enfermedad de Parkinson, la droxidopa frente a placebo podría mejorar al muy corto plazo algunas puntuaciones para la evaluación de los síntomas, y aumentar la presión arterial sistólica y diastólica. Sin embargo, existen dudas si estas mejoras son clínicamente importantes y las personas que recibieron el fármaco presentaron mayores tasas de eventos adversos que llevaron a su discontinuación. No se halló evidencia que evalúe la droxidopa frente a otros tratamientos farmacológicos disponibles para la población objetivo, como tampoco si estos beneficios se mantienen en el tiempo. No se hallaron evaluaciones económicas ni recomendaciones para Argentina y Latinoamérica. Instituciones de referencia relevadas en países de altos ingresos no la mencionan dentro de sus recomendaciones y tampoco dan cobertura. Según los precio de adquisición relevados para Estados Unidos, el costo mensual del tratamiento sería aproximadamente de ARS 655.707 a 3.920.353.

Advances in the Pharmacological and Non-pharmacological Management of Non-motor Symptoms in Parkinson's Disease: An Update Since 2017.

BACKGROUND: Non-motor symptoms (NMS) are an important and ubiquitous determinant of quality of life in Parkinson's disease (PD). However, robust evidence for their treatment is still a major unmet need. OBJECTIVE: This study aimed to provide an updated review on advances in pharmacological, nonpharmacological, and exercise-based interventions for NMS in PD, covering the period since the publication of the MDS Task Force Recommendations. METHODS: We performed a literature search to identify pharmacological, non-pharmacological, and exercise-based interventions for NMS in PD. As there are recent reviews on the subject, we have only included studies from the 1st of January 2017 to the 1st of December 2021 and limited our search to randomised and non-randomised (including open-label) clinical trials. RESULTS: We discuss new strategies to manage NMS based on data that have become available since 2017, for instance, on the treatment of orthostatic hypotension with droxidopa, several dopaminergic treatment options for insomnia, and a range of non-pharmacological and exercise-based interventions for cognitive and neuropsychiatric symptoms, pain, and insomnia and excessive sleepiness. CONCLUSION: Recent evidence suggests that targeted non-pharmacological treatments, as well as some other NMS management options, may have a significant beneficial effect on the quality of life and need to be considered in the pathways of treatment of PD.

Droxidopa in the Management of Hepatorenal Syndrome.

PurposeHepatorenal syndrome (HRS) is renal dysfunction associated with the hemodynamic consequences of advanced liver disease and cirrhosis. HRS is associated with a high mortality, and there remain high failure rates with first-line therapy aimed at improving perfusion. We report the use of droxidopa, an oral norepinephrine precursor, to aid in the management of HRS-AKI refractory to first-line therapy. Summary: A 51-year-old Caucasian male with alcohol-related cirrhosis presented with 1-week history of pre-syncope and falls. He was found to have acute kidney injury meeting diagnostic criteria of HRS based on absence of identifiable contributing factors. After no response to volume expansion, medical management was initiated with midodrine and octreotide and eventually escalated to norepinephrine intravenous infusion. The patient's renal function and urine output improved initially on norepinephrine, but worsened when attempting to wean to a suitable outpatient regimen, becoming dependent upon norepinephrine. On day 13 of hospitalization, droxidopa was initiated at a dose of 100 mg three times daily and titrated to a dose of 400 mg three times daily. Norepinephrine infusion was weaned and discontinued on day 16 of hospitalization. The patient remained hemodynamically stable and was able to be discharged on droxidopa 400 mg three times daily, midodrine 20 mg three times day, and octreotide 200 mcg three times daily. Conclusion: Droxidopa, an oral norepinephrine precursor, presents a novel adjunctive agent for management of HRS refractory to first-line medical management.

Droxidopa management by an integrated health-system specialty pharmacy team.

BACKGROUND: Droxidopa, indicated for the treatment of symptomatic neurogenic orthostatic hypotension, can be challenging for patients to access owing to manufacturer and payer restrictions, and requires close monitoring to ensure safety and effectiveness. OBJECTIVE: This practice report describes the development and outcomes of an integrated neurology specialty pharmacy team for droxidopa management. PRACTICE DESCRIPTION: An integrated health-system specialty pharmacy (HSSP) connected to an academic institution with integrated specialty pharmacists working in collaboration with the providers in both the neurology and autonomic disfunction clinic. PRACTICE INNOVATION: In May 2017, the integrated HSSP developed droxidopa management services. Based on clinic-identified needs, the specialty pharmacy team completed droxidopa access requirements (insurance approval and affordability), provided comprehensive medication education at droxidopa initiation, and developed and executed droxidopa titration and monitoring plans in collaboration with providers. While patients were on droxidopa therapy, specialty pharmacist staff (pharmacists and technicians) monitored patients for safety and response to therapy and communicated with the health care team through the shared electronic health record. EVALUATION METHODS: We performed a retrospective cohort analysis of adult patients with at least 3 fills of droxidopa using the integrated specialty pharmacy services from May 2017 to April 2020. Outcomes included persistence (defined as lack of 60-day gap in treatment), adherence (calculated using pharmacy claims and proportion of days covered [PDC]), and number and type of pharmacist interventions after droxidopa initiation. RESULTS: Of the 83 patients reviewed, 60 patients (72%) were persistent on droxidopa therapy over the study period. The median PDC was 0.98 (interquartile range 0.90-1.00). Over 36 months, the specialty pharmacist performed 60 interventions after droxidopa initiation, most related to dose changes, drug-drug interaction management, and medication reconciliation. CONCLUSION: The development of integrated specialty pharmacy services for patients prescribed droxidopa resulted in high droxidopa persistence and adherence. Interventions from the specialty pharmacist ensured droxidopa remained safe and appropriate for patients.

Droxidopa reduces postural sway in Parkinson disease patients with orthostatic hypotension.

We evaluate the effect of droxidopa on gait and balance measures in nine patients with Parkinson's disease and neurogenic orthostatic hypotension. Computerized gait/balance analysis showed a significant effect of droxidopa in reducing postural sway. Future studies may determine if such effect translates into improvement in postural reflexes and falls.

The cause of eyelid ptosis, orthostatic hypotension and exercise intolerance.

To provide more insight in the delay in diagnosis and expectation of treatment adapted for the paediatrician, the data were collected from patients described with dopamine beta-hydroxylase deficiency are evaluated. More insight in clinical features of dopamine beta-hydroxylase deficiency consisting mainly of eyelid ptosis, orthostatic hypotension, hypoglycaemia and exercise intolerance, explains the delay in diagnosis of this congenital disorder, although all symptoms some more concealed are present. An increasing experience by L-DOPS, a resurrection for the patient, allows recommendations for early treatment. An explanation for the delay in diagnosis is provided together with the advice for treatment.

Orthostatic Hypotension: A Practical Approach.

Orthostatic hypotension is defined as a decrease in blood pressure of 20 mm Hg or more systolic or 10 mm Hg or more diastolic within three minutes of standing from the supine position or on assuming a head-up position of at least 60 degrees during tilt table testing. Symptoms are due to inadequate physiologic compensation and organ hypoperfusion and include headache, lightheadedness, shoulder and neck pain (coat hanger syndrome), visual disturbances, dyspnea, and chest pain. Prevalence of orthostatic hypotension in the community setting is 20% in older adults and 5% in middle-aged adults. Risk factors such as diabetes mellitus increase the prevalence of orthostatic hypotension in all age groups. Orthostatic hypotension is associated with a significant increase in cardiovascular risk and falls, and up to a 50% increase in relative risk of all-cause mortality. Diagnosis is confirmed by performing a bedside simplified Schellong test, which consists of blood pressure and heart rate measurements after five minutes in the supine position and three minutes after moving to a standing position. If the patient is unable to stand safely or the clinical suspicion for orthostatic hypotension is high despite normal findings on the bedside test, head-up tilt table testing is recommended. Orthostatic hypotension is classified as neurogenic or nonneurogenic, depending on etiology and heart rate response. Treatment goals for orthostatic hypotension are reducing symptoms and improving quality of life. Initial treatment focuses on the underlying cause and adjusting potentially causative medications. Nonpharmacologic strategies include dietary modifications, compression garments, physical maneuvers, and avoiding environments that exacerbate symptoms. First-line medications include midodrine and droxidopa. Although fludrocortisone improves symptoms, it has concerning long-term effects.

Analysis of L-DOPA and droxidopa binding to human ß2-adrenergic receptor.

Over the last two decades, an increasing number of studies has been devoted to a deeper understanding of the molecular process involved in the binding of various agonists and antagonists to active and inactive conformations of ß2-adrenergic receptor (ß2AR). The 3.2 Å x-ray crystal structure of human ß2AR active state in combination with the endogenous low affinity agonist adrenaline offers an ideal starting structure for studying the binding of various catecholamines to adrenergic receptors. We show that molecular docking of levodopa (L-DOPA) and droxidopa into rigid and flexible ß2AR models leads for both ligands to binding anchor sites comparable to those experimentally reported for adrenaline, namely D113/N312 and S203/S204/S207 side chains. Both ligands have a hydrogen bond network that is extremely similar to those of noradrenaline and dopamine. Interestingly, redocking neutral and protonated versions of adrenaline to rigid and flexible ß2AR models results in binding poses that are more energetically stable and distinct from the x-ray crystal structure. Similarly, lowest energy conformations of noradrenaline and dopamine generated by docking into flexible ß2AR models had binding free energies lower than those of best poses in rigid receptor models. Furthermore, our findings show that L-DOPA and droxidopa molecules have binding affinities comparable to those predicted for adrenaline, noradrenaline, and dopamine, which are consistent with previous experimental and computational findings and supported by the molecular dynamics simulations of ß2AR-ligand complexes performed here.

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).

Dysautonomia: A Forgotten Condition - Part 1. / Disautonomia: Uma Condição Esquecida ­ Parte 1.

Dysautonomia covers a range of clinical conditions with different characteristics and prognoses. They are classified as Reflex Syndromes, Postural Orthostatic Tachycardia Syndrome (POTS), Chronic Fatigue Syndrome, Neurogenic Orthostatic Hypotension (nOH) and Carotid Sinus Hypersensitivity Syndrome. Reflex (vasovagal) syndromes will not be discussed in this article. Reflex (vasovagal) syndromes are mostly benign and usually occur in patients without an intrinsic autonomic nervous system (ANS) or heart disease. Therefore, they are usually studied separately. Cardiovascular Autonomic Neuropathy (CAN) is the term most currently used to define dysautonomia with impairment of the sympathetic and/or parasympathetic cardiovascular autonomic nervous system. It can be idiopathic, such as multisystemic atrophy or pure autonomic failure, or secondary to systemic pathologies such as diabetes mellitus, neurodegenerative diseases, Parkinson's disease, dementia syndromes, chronic renal failure, amyloidosis and it may also occur in the elderly. The presence of Cardiovascular Autonomic Neuropathy (CAN) implies greater severity and worse prognosis in various clinical situations. Detection of Orthostatic Hypotension (OH) is a late sign and means greater severity in the context of dysautonomia, defined as Neurogenic Orthostatic Hypotension (nOH). It must be differentiated from hypotension due to hypovolemia or medications, called non-neurogenic orthostatic hypotension (nnOH). OH can result from benign causes, such as acute, chronic hypovolemia or use of various drugs. However, these drugs may only reveal subclinical pictures of Dysautonomia. All drugs of patients with dysautonomic conditions should be reevaluated. Precise diagnosis of CAN and the investigation of the involvement of other organs or systems is extremely important in the clinical suspicion of pandysautonomia. In diabetics, in addition to age and time of disease, other factors are associated with a higher incidence of CAN, such poor glycemic control, hypertension, dyslipidemia and obesity. Among diabetic patients, 38-44% can develop Dysautonomia, with prognostic implications and higher cardiovascular mortality. In the initial stages of DM, autonomic dysfunction involves the parasympathetic system, then the sympathetic system and, later on, it presents as orthostatic hypotension. Valsalva, Respiratory and Orthostatic tests (30:15) are the gold standard methods for the diagnosis of CAN. They can be associated with RR Variability tests in the time domain, and mainly in the frequency domain, to increase the sensitivity (protocol of the 7 tests). These tests can detect initial or subclinical abnormalities and assess severity and prognosis. The Tilt Test should not be the test of choice for investigating CAN at an early stage, as it detects cases at more advanced stages. Tilt response with a dysautonomic pattern (gradual drop in blood pressure without increasing heart rate) may suggest CAN. Treatment of patients at moderate to advanced stages of dysautonomia is quite complex and often refractory, requiring specialized and multidisciplinary evaluation. There is no cure for most types of Dysautonomia at a late stage. NOH patients can progress with supine hypertension in more than 50% of the cases, representing a major therapeutic challenge. The immediate risk and consequences of OH should take precedence over the later risks of supine hypertension and values greater than 160/90 mmHg are tolerable. Sleeping with the head elevated (20-30 cm), not getting up at night, taking short-acting antihypertensive drugs for more severe cases, such as losartan, captopril, clonidine or nitrate patches, may be necessary and effective in some cases. Preventive measures such as postural care; good hydration; higher salt intake; use of compression stockings and abdominal straps; portioned meals; supervised physical activity, mainly sitting, lying down or exercising in the water are important treatment steps. Various drugs can be used for symptomatic nOH, especially fludrocortisone, midodrine and droxidopa, the latter not available in Brazil. The risk of exacerbation or triggering supine hypertension should be considered. Chronic Fatigue Syndrome represents a form of Dysautonomia and has been renamed as a systemic disease of exercise intolerance, with new diagnostic criteria: 1 - Unexplained fatigue, leading to occupational disability for more than 6 months; 2 - Feeling ill after exercising; 3 - Non-restorative sleep; 4 - One of the following findings: cognitive impairment or orthostatic intolerance. Several pathologies today have evolved with chronic fatigue, being called chronic diseases associated with chronic fatigue. Postural orthostatic tachycardia syndrome (POTS), another form of presentation of dysautonomic syndromes, is characterized by sustained elevation of heart rate (HR) ≥30 bpm (≥40 bpm if <20 years) or HR ≥120 bpm, in the first 10 minutes in an orthostatic position or during the tilt test, without classical orthostatic hypotension associated. A slight decrease in blood pressure may occur. Symptoms appear or get worse in an orthostatic position, with dizziness, weakness, pre-syncope, palpitations, and other systemic symptoms being common.

O termo disautonomia abrange um conjunto de condições clínicas com características e prognósticos distintos. Classificam-se em síndromes reflexas, síndrome postural ortostática taquicardizante (SPOT), síndrome da fadiga crônica, Hipotensão Ortostática Neurogênica (HON) e a Síndrome da hipersensibilidade do seio carotídeo. As síndromes reflexas (vasovagal) não serão discutidas neste artigo. As síndromes reflexas (vasovagal) são, na maioria das vezes, benignas, e ocorrem usualmente em pacientes sem doença intrínseca do sistema nervoso autônomo (SNA) ou do coração. Por isso, geralmente são estudadas separadamente. O termo neuropatia autonômica cardiovascular (NAC) é o mais utilizado na atualidade para definir as disautonomias com comprometimento do sistema nervoso autônomo cardiovascular simpático e/ou parassimpático. Pode ser idiopática, como a atrofia multissistêmica ou a falência autonômica pura, ou secundária a patologias sistêmicas como diabetes mellitus, doenças neurodegenerativas, doença de Parkinson, síndromes demenciais, insuficiência renal crônica, amiloidose, podendo também acometer idosos. A presença de neuropatia autonômica cardiovascular (NAC) implica em maior gravidade e pior prognóstico em diversas situações clínicas. A detecção de hipotensão ortostática (HO) é um sinal tardio e significa maior gravidade no contexto das disautonomias, definida como hipotensão ortostática neurogênica (HON). Deve ser diferenciada das hipotensões por hipovolemia ou medicamentosas, chamadas de hipotensão ortostática não neurogênica (HONN). A HO pode decorrer de causas benignas, como a hipovolemia aguda, crônica, ou ao uso de diversos fármacos. Esses fármacos podem, entretanto, apenas desmascarar quadros subclínicos de disautonomia. Deve-se reavaliar todos os fármacos de pacientes com quadros disautonômicos. O diagnóstico preciso de NAC e a investigação do envolvimento de outros órgãos ou sistemas é de extrema importância na suspeita clínica de uma pandisautonomia. No diabético, além da idade e do tempo de doença, outros fatores estão associados a maior ocorrência de NAC, como descontrole glicêmico, hipertensão, dislipidemia e obesidade. Entre os pacientes diabéticos, 38­44% podem evoluir com disautonomia, com implicações prognósticas e maior mortalidade cardiovascular. Nas etapas iniciais da DM, a disfunção autonômica envolve o sistema parassimpático, posteriormente o simpático e mais tardiamente manifesta-se com hipotensão ortostática. Os testes de Valsalva, respiratório e ortostático (30:15) são os métodos de padrão ouro para o diagnóstico de NAC. Eles podem ser associados aos testes de variabilidade RR no domínio do tempo, e principalmente da frequência, para aumento da sensibilidade (protocolo dos 7 testes). Esses testes podem detectar alterações iniciais ou subclínicas e avaliar a gravidade e o prognóstico. O teste de inclinação (tilt test) não deve ser o exame de escolha para investigação de NAC em fase inicial, pois detecta casos em fases mais avançadas. A resposta no tilt com padrão disautonômico (queda gradativa da pressão arterial sem aumento da frequência cardíaca) pode sugerir NAC. O tratamento dos pacientes em fases moderadas a avançadas das disautonomias é bastante complexo e muitas vezes refratário, necessitando de avaliação especializada e multidisciplinar. Não há cura para a maioria das disautonomias em fase tardia. Os pacientes com HON podem evoluir com hipertensão supina em mais de 50% dos casos, representando um grande desafio terapêutico. O risco imediato e as consequências da HO devem ter preferência sobre os riscos mais tardios da hipertensão supina e valores maiores que 160/90 mmHg são toleráveis. Medidas como dormir com a cabeceira elevada (20­30 cm), não levantar à noite, uso de anti-hipertensivo de ação curta noturna para casos mais severos, como a losartana, captopril, clonidina ou adesivos de nitratos, podem ser necessários e efetivos em alguns casos. As medidas preventivas como cuidados posturais, boa hidratação, maior ingesta de sal, uso de meias e cintas abdominais compressoras, refeições fracionadas, atividade física supervisionada principalmente sentada, deitada ou exercícios na água são etapas importantes no tratamento. Diversos fármacos podem ser usados para HON sintomática, principalmente a fludrocortisona, a midodrina e a droxidopa. Esses últimas não estão disponíveis no Brasil. O risco de exacerbação ou desencadeamento de hipertensão supina deve ser considerado. A síndrome da fadiga crônica representa uma forma de disautonomia e tem sido renomeada como doença sistêmica de intolerância ao exercício, com novos critérios diagnósticos: 1 - Fadiga inexplicada, levando a incapacidade para o trabalho por mais que 6 meses; 2 - Mal-estar após exercício; 3 - Sono não reparador; 4 - Mais um dos seguintes achados: comprometimento cognitivo ou intolerância ortostática. Várias patologias na atualidade têm evoluído com fadiga crônica, sendo denominadas de doenças crônicas associadas a fadiga crônica. A síndrome postural ortostática taquicardizante (SPOT), outra forma de apresentação das síndromes disautonômicas, é caracterizada por elevação sustentada da frequência cardíaca (FC) ≥30 bpm (≥40 bpm se <20 anos) ou FC ≥120 bpm, nos primeiros 10 minutos em posição ortostática ou durante o tilt test, sem hipotensão ortostática clássica associada. Pode ocorrer leve redução na pressão arterial. Os sintomas manifestam-se ou pioram em posição ortostática, sendo comuns a tontura, fraqueza, pré-síncope, palpitações, além de outros sintomas sistêmicos.

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.

Prevention and Management of Supine Hypertension in Patients With Orthostatic Hypotension.

BACKGROUND: Orthostatic hypotension (OH) is a potentially debilitating condition caused by dysfunction of the autonomic nervous system, which is essential for the physiologic response to orthostatic posture. In addition to OH, autonomic dysfunction may also be associated with the development of concurrent supine hypertension (SH). AREAS OF UNCERTAINTY: This paradoxical effect speaks to the complexity of the pathogenesis of autonomic disease and greatly complicates management of these patients. Clinicians are faced with a dilemma because aggressive treatment of orthostatic intolerance can worsen supine hypertension and attempts to control supine hypertension can worsen orthostatic intolerance. DATA SOURCES: Systematic review of the published literature. PREVENTION OF SUPINE HYPERTENSION: Patients should aim to avoid known stressors, perform physical maneuvers (eg, slowly getting up from bed, sleeping with head of bed elevated), manage underlying related conditions (eg, diabetes mellitus), and exercise. MANAGEMENT OF SUPINE HYPERTENSION: With failure of conservative management, patients may advance to pharmacologic therapy. It is important to understand the underlying suspected etiology of the syndrome of supine hypertension and OH (SH-OH) to select promising pharmacologic agents. This article reviews medical treatment options to work toward achieving a better quality of life for patients afflicted with this disease. Although clonidine and beta-blockers can be used to treat hypertension without causing significant hypotension, midodrine, pyridostigmine, and droxidopa may be helpful in preventing OH. CONCLUSION: The etiology and severity of autonomic dysfunction vary widely between patients, suggesting a need for an individualized treatment approach. Achieving perfect blood pressure control is not a realistic goal. Rather, treatment should be aimed at improving the patient's quality of life and decreasing their risk of injury and organ damage.

Clinical presentation and long-term follow-up of dopamine beta hydroxylase deficiency.

Dopamine beta hydroxylase (DBH) deficiency is an extremely rare autosomal recessive disorder with severe orthostatic hypotension, that can be treated with L-threo-3,4-dihydroxyphenylserine (L-DOPS). We aimed to summarize clinical, biochemical, and genetic data of all world-wide reported patients with DBH-deficiency, and to present detailed new data on long-term follow-up of a relatively large Dutch cohort. We retrospectively describe 10 patients from a Dutch cohort and 15 additional patients from the literature. We identified 25 patients (15 females) from 20 families. Ten patients were diagnosed in the Netherlands. Duration of follow-up of Dutch patients ranged from 1 to 21 years (median 13 years). All patients had severe orthostatic hypotension. Severely decreased or absent (nor)epinephrine, and increased dopamine plasma concentrations were found in 24/25 patients. Impaired kidney function and anemia were present in all Dutch patients, hypomagnesaemia in 5 out of 10. Clinically, all patients responded very well to L-DOPS, with marked reduction of orthostatic complaints. However, orthostatic hypotension remained present, and kidney function, anemia, and hypomagnesaemia only partially improved. Plasma norepinephrine increased and became detectable, while epinephrine remained undetectable in most patients. We confirm the core clinical characteristics of DBH-deficiency and the pathognomonic profile of catecholamines in body fluids. Impaired renal function, anemia, and hypomagnesaemia can be part of the clinical presentation. The subjective response to L-DOPS treatment is excellent and sustained, although the neurotransmitter profile in plasma does not normalize completely. Furthermore, orthostatic hypotension as well as renal function, anemia, and hypomagnesaemia improve only partially.

Droxidopa alters dopamine neuron and prefrontal cortex activity and improves attention-deficit/hyperactivity disorder-like behaviors in rats.

Finding alternative treatments for attention-deficit/hyperactivity disorder (ADHD) is crucial given the safety and efficacy problems of current ADHD medications. Droxidopa, also known as L-threo-dihydroxyphenylserine (L-DOPS), is a norepinephrine prodrug that enhances brain norepinephrine and dopamine levels. In this study, we used electrophysiological tests to examine effects of L-DOPS on the prefrontal cortex (PFC) and dopamine neurons in the ventral tegmental area. We also conducted behavioral tests to assess L-DOPS' effects on ADHD-like behaviors in rats. In chloral hydrate-anesthetized rats, PFC local field potentials oscillated between the active, depolarized UP state and the hyperpolarized DOWN state. Mimicking the effect of d-amphetamine, L-DOPS, given after the peripheral amino acid decarboxylase inhibitor, benserazide (BZ), increased the amount of time the PFC spent in the UP state, indicating an excitatory effect of L-DOPS on PFC neurons. Like d-amphetamine, L-DOPS also inhibited dopamine neurons, an effect significantly reversed by the D2-like receptor antagonist raclopride. In the behavioral tests, BZ + L-DOPS improved hyperactivity, inattention and impulsive action of the adolescent spontaneously hypertensive rat (SHR/NCrl), well-validated animal model of the combined type of ADHD. BZ + L-DOPS also reduced impulsive choice and impulsive action of Wistar rats, but did not ameliorate the inattentiveness of Wistar Kyoto rats (WKY/NCrl), proposed model of the ADHD-predominantly inattentive type. In conclusion, L-DOPS produced effects on the PFC and dopamine neurons characteristic of drugs used to treat ADHD. BZ + L-DOPS ameliorated ADHD-like behaviors in rats suggesting its potential as an alternative ADHD treatment.

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

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