Mechanisms and management of gastrointestinal symptoms in postural orthostatic tachycardia syndrome

AGA Clinical Practice Update on GI Manifestations and Autonomic or Immune Dysfunction in Hypermobile Ehlers-Danlos Syndrome: Expert Review

DESCRIPTION

The purpose of this Clinical Practice Update Expert Review is to describe key principles in the evaluation and management of patients with disorders of gut-brain interaction (DGBI) and hypermobile Ehlers-Danlos syndrome (hEDS) or hypermobility spectrum disorders (HSDs) with coexisting postural orthostatic tachycardia syndrome (POTS) and/or mast cell activation syndrome (MCAS).

METHODS

This expert review was commissioned and approved by the American Gastroenterological Association (AGA) Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. These Best Practice Advice statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these Best Practice Advice statements do not carry formal ratings regarding the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: Clinicians should be aware of the observed associations between hEDS or HSDs and POTS and/or MCAS and their overlapping gastrointestinal (GI) manifestations; while theoretical explanations exist, experimental evidence of the biological mechanisms that explain relationships is limited and evolving. BEST PRACTICE ADVICE 2: Testing for POTS/MCAS should be targeted to patients presenting with clinical manifestations of POTS/MCAS, but universal testing for POTS/MCAS in all patients with hEDS/HSDs is not supported by the current evidence. BEST PRACTICE ADVICE 3: Gastroenterologists seeing patients with DGBI should inquire about joint hypermobility and strongly consider incorporating the Beighton score for assessing joint hypermobility into their practice as a screening tool; if the screen is positive, gastroenterologists may consider applying 2017 diagnostic criteria to diagnose hEDS (https://www.ehlers-danlos.com/wp-content/uploads/2017/05/hEDS-Dx-Criteria-checklist-1.pdf) or offer appropriate referral to a specialist where resources are available. BEST PRACTICE ADVICE 4: Testing for POTS through postural vital signs (eg, symptomatic increase in heart rate of 30 beats/min or more with 10 minutes of standing during an active stand or head-up tilt table test in the absence of orthostasis) and referral to specialty practices (eg, cardiology or neurology) for autonomic testing should be considered in patients with hEDS/HSDs and refractory GI symptoms who also report orthostatic intolerance after exclusion of medication side effects and appropriate lifestyle or behavioral modifications (eg, adequate hydration and physical exercise) have been attempted but is not required for all patients with hEDS/HSDs who report GI symptoms alone. BEST PRACTICE ADVICE 5: In patients presenting to gastroenterology providers, testing for mast cell disorders including MCAS should be considered in patients with hEDS/HSDs and DGBI who also present with episodic symptoms that suggest a more generalized mast cell disorder (eg, visceral and somatic pain, pruritus, flushing, sweating, urticaria, angioedema, wheezing, tachycardia, abdominal cramping, vomiting, nausea, diarrhea, urogynecological and neurological complaints) involving 2 or more physiological systems (eg, cutaneous, GI, cardiac, respiratory, and neuropsychiatric), but current data do not support the use of these tests for routine evaluation of GI symptoms in all patients with hEDS/HSDs without clinical or laboratory evidence of a primary or secondary mast cell disorder. BEST PRACTICE ADVICE 6: If MCAS is suspected, diagnostic testing with serum tryptase levels collected at baseline and 1-4 hours following symptom flares may be considered by the gastroenterologist; increases of 20% above baseline plus 2 ng/mL are necessary to demonstrate evidence of mast cell activation. BEST PRACTICE ADVICE 7: If a diagnosis of MCAS is supported through clinical and/or laboratory features, patients should be referred to an allergy specialist or mast cell disease research center where additional testing (eg, urinary N-methylhistamine, leukotriene E4, 11β-prostaglandin F2) may be performed. BEST PRACTICE ADVICE 8: Diagnostic evaluation of GI symptoms consistent with DGBI in patients with hEDS/HSDs and comorbid POTS and/or MCAS should follow a similar approach to the evaluation of DGBI as in the general population including the use of a positive symptom-based diagnostic strategy and limited noninvasive testing. BEST PRACTICE ADVICE 9: Testing for celiac disease may be considered earlier in the diagnostic evaluation of patients with hEDS/HSDs who report a variety of GI symptoms and not only limited to those with diarrhea. There is insufficient research to support routine testing for disaccharidase deficiencies or other diet-mediated mechanisms as causes of GI symptoms in hEDS/HSDs. BEST PRACTICE ADVICE 10: Diagnostic testing for functional defecation disorders with anorectal manometry, balloon expulsion test, or defecography should be considered in patients with hEDS/HSDs and lower GI symptoms such as incomplete evacuation given the high prevalence of pelvic floor dysfunction, especially rectal hyposensitivity, in this population. BEST PRACTICE ADVICE 11: In patients with hEDS/HSDs and comorbid POTS who report chronic upper GI symptoms, timely diagnostic testing of gastric motor functions (eg, measurement of gastric emptying and/or accommodation) should be considered after appropriate exclusion of anatomical and structural diseases, as abnormal gastric emptying may be more common than in the general population. BEST PRACTICE ADVICE 12: Medical management of GI symptoms in hEDS/HSDs and POTS/MCAS should focus on treating the most prominent GI symptoms and abnormal GI function test results. In addition to general DGBIs and GI motility disorder treatment, management should also include treating any symptoms attributable to POTS and/or MCAS. BEST PRACTICE ADVICE 13: Treatment of POTS may include increasing fluid and salt intake, exercise training, and use of compression garments. Special pharmacological treatments for volume expansion, heart rate control, and vasoconstriction with integrated care from multiple specialties (eg, cardiology, neurology) should be considered in patients who do not respond to conservative lifestyle measures. BEST PRACTICE ADVICE 14: When MCAS is suspected, patients can benefit from treatment with histamine receptor antagonists and/or mast cell stabilizers, in addition to avoiding triggers such as certain foods, alcohol, strong smells, temperature changes, mechanical stimuli (eg, friction), emotional distress (eg, pollen, mold), or specific medications (eg, opioids, nonsteroidal anti-inflammatory agents, iodinated contrast). BEST PRACTICE ADVICE 15: Besides general nutritional support, special diets including a gastroparesis diet (ie, small particle diet) and various elimination diets (eg, low fermentable carbohydrates, gluten- or dairy-free, low-histamine diets) can be considered for improving GI symptoms. Dietary interventions should be delivered with appropriate nutritional counseling or guidance to avoid the pitfalls of restrictive eating. BEST PRACTICE ADVICE 16: Management of chronic GI symptoms in patients with hEDS/HSDs who do not exhibit symptoms consistent with POTS or MCAS should align with existing approaches to management of DGBI and GI motility disorders in the general population, including integrated multidisciplinary care involving multiple specialties, where appropriate (eg, cardiology, rheumatology, dietician, psychology).

Prevalence of mast cell activation disorders and hereditary alpha tryptasemia among patients with postural orthostatic tachycardia syndrome and Ehlers-Danlos syndrome: A systematic review

BACKGROUND

Postural orthostatic tachycardia syndrome (POTS) and Ehlers-Danlos syndrome (EDS) are often reported to occur concurrently with mast cell activation disorders (MCADs) and hereditary alpha tryptasemia (HAT). However, it remains unclear whether evidence supporting this relationship exists.

OBJECTIVE

To determine the prevalence of MCADs and HAT in patients diagnosed with having EDS and or POTS.

METHODS

We conducted a systematic search of MEDLINE (OVID), EMBASE (OVID), Scopus, and Web of Science with the assistance of an experienced medical librarian. We focused on patients with any MCAD or HAT in conjunction with a diagnosis of POTS and/or EDS.

RESULTS

A total of 200 records were screened, 107 were excluded based on the title or abstract, 92 full texts were reviewed, and 1 record was not retrieved. No studies were identified that met our primary criterion of including patients diagnosed with any MCAD or HAT alongside POTS and/or EDS based on our prespecified diagnostic criteria.

CONCLUSION

Our review did not find evidence to confirm a relationship between MCADs, HAT, POTS, and EDS. However, it must be mentioned that 1 study revealed an association between mast cell activation syndrome, POTS, and EDS and came close to meeting the full diagnostic criteria for mast cell activation syndrome, unlike other studies. This indicates that further research using strict and validated diagnostic criteria is needed to clarify whether a true association between conditions exists.

Gastrointestinal manifestations of long COVID

Long COVID is estimated to have affected 6.9 % of US adults, 17.8 million people in the US alone, as of early 2023. While SARS-CoV-2 is primarily considered a respiratory virus, gastrointestinal (GI) symptoms are also frequent in patients with coronavirus disease 2019 (COVID-19) and in patients with Long COVID. The risk of developing GI symptoms is increased with increasing severity of COVID-19, the presence of GI symptoms in the acute infection, and psychological distress both before and after COVID-19. Persistence of the virus in the GI tract, ensuing inflammation, and alteration of the microbiome are all likely mediators of the effects of SARS Co-V-2 virus on the gut. These factors may all increase intestinal permeability and systemic inflammation. GI inflammation and dysbiosis can change the absorption and metabolism of tryptophan, an important neurotransmitter. Long COVID GI symptoms resemble a Disorder of Gut Brain Interaction (DGBI) such as post infection Irritable Bowel Syndrome (IBS). Current standards of treatment for IBS can guide our treatment of Long COVID patients. Dysautonomia, a frequent Long COVID condition affecting the autonomic nervous system, can also affect the GI tract, and must be considered in Long COVID patients with GI symptoms. Long COVID symptoms fall within the broader category of Infection Associated Chronic Conditions (IACCs). Research into the GI symptoms of Long COVID may further our understanding of other post infection chronic GI conditions, and elucidate the roles of therapeutic options including antivirals, probiotics, neuromodulators, and treatments of dysautonomia.

Postural Orthostatic Tachycardia Syndrome Associated with COVID-19: A Narrative Review

Postural orthostatic tachycardia syndrome (POTS) is a complex condition marked by an atypical autonomic response to standing, leading to orthostatic intolerance and significant tachycardia without accompanying hypotension. In recent studies, a considerable number of individuals recovering from COVID-19 have been reported to experience POTS within 6 to 8 months post-infection. Key symptoms of POTS include fatigue, difficulty with orthostatic tolerance, tachycardia, and cognitive challenges. The underlying causes of POTS following COVID-19 remain unknown, with various theories proposed such as renin-angiotensin-aldosterone system (RAAS) dysregulation, hyperadrenergic reaction, and direct viral infection. Healthcare professionals should be vigilant for POTS in patients who have recovered from COVID-19 and are experiencing signs of autonomic dysfunction and use diagnostic procedures such as the tilt-up table test for confirmation. COVID-19-related POTS should be approached with a holistic strategy. Although many patients show improvement with initial non-drug treatments, for subjects who do not respond and exhibit more severe symptoms, medication-based therapies may be necessary. The current understanding of COVID-19-related POTS is limited, underscoring the need for more research to increase knowledge and enhance treatment approaches.

Mast Cell Activation Syndrome and Gut Dysfunction: Diagnosis and Management

PURPOSE OF REVIEW

Mast cell activation syndrome (MCAS) is a clinical disorder that may explain irritable bowel syndrome (IBS) type symptoms as well as other allergic symptoms experienced by an individual. The diagnosis and treatment of MCAS with specific focus on gastrointestinal (GI) manifestations is reviewed.

RECENT FINDINGS

Although biomarkers for MCAS remain elusive, testing for baseline serum tryptase will distinguish the type of mast cell disorder and urine tests for mast cell mediator metabolites may support the diagnosis. Endoscopy and Colonoscopy with biopsies is not used to diagnose MCAS but is important to rule out other conditions that may cause symptoms. There is increased awareness of the association between MCAS and autonomic dysfunction, small fiber neuropathy, and connective tissue disorders which all impact GI symptoms. MCAS is a disorder often of unknown etiology (idiopathic) and characterized by intermittent allergy type symptoms that affect multiple organ systems after exposure to a trigger. GI symptoms including abdominal cramping and loose stool are prominent and mimic those of IBS. Diagnostic testing is performed to assess for elevations in mast cell mediators during symptoms and to rule out other conditions. A comprehensive treatment plan includes medications that target mast cells, treatments for associated conditions including autonomic dysfunction, and management of comorbid psychiatric illness and nutritional deficits.

Gastrointestinal symptoms in patients with postural orthostatic tachycardia syndrome in relation to hemodynamic findings and immunological factors

Gastrointestinal (GI) symptoms are common in postural orthostatic tachycardia syndrome (POTS). We aimed to explore the prevalence and severity of GI symptoms in POTS, and to investigate immunological factors, hemodynamic findings, and their possible association with GI symptoms in POTS. Forty-three patients (93% female, median age 30.6 (26.0-41.0) years), previously diagnosed with POTS and 74 healthy controls (78% female, median age 35.6 (28.8-41.7) years) were included. The participants completed a questionnaire including prevalence of GI symptoms, the irritable bowel syndrome severity scoring system (IBS-SSS), and visual analog scale for IBS (VAS-IBS). All POTS patients were previously examined by tilt test (2010-2021) and the vast majority with more recent active standing test (2017-2021), which included monitoring of heart rate (HR). ΔHR was calculated as difference between supine and upright position. Continuous variables from IBS-SSS and VAS-IBS were correlated to ΔHR. A microarray containing several autoantigens commonly targeted in systemic autoimmune disorders was used to assess prevalent autoantibodies in POTS and controls. Total IgE and S-tryptase were analyzed. GI symptoms were more prevalent and severe in POTS than in controls; nausea being the most prevalent (79.1% vs 4.9%, p < 0.001) and bloating and flatulence being the most severe (median 65 (25-88) vs 0 (0-14), p < 0.001). The median total IBS-SSS was 213 (135-319) in POTS vs 13 (0-54) in controls (p < 0.001). Total IBS-SSS was associated with low psychological wellbeing (r = 0.539, p < 0.001) in POTS. ΔHRmax correlated inversely with abdominal pain (r = -0.406, p = 0.007). After adjustments for psychological wellbeing, total IBS-SSS still associated inversely with ΔHR10min (β: 4.748; 95% CI: -9.172 to -0.324; p = 0.036). Similar results were seen with active standing test. The prevalence of autoantibodies did not differ between POTS and controls (29.4% vs 33.3%, p = 0.803). There was no association between GI symptoms and autoantibody status. Total IgE and tryptase were elevated in a few cases. This study confirms the high prevalence of GI symptoms in POTS. More pronounced tachycardia upon tilt table testing seems to be inversely correlated with severity of chronic GI symptoms in POTS. This study did not support the hypothesis that POTS is associated with immunological factors.

Cardiovascular Symptoms, Dysautonomia, and Quality of Life in Adult and Pediatric Patients with Hypermobile Ehlers-Danlos Syndrome: A Brief Review

BACKGROUND

Hypermobile Ehlers-Danlos Syndrome (hEDS) is a connective tissue disorder characterized by joint hypermobility and other systemic manifestations, such as cardiovascular symptoms, musculoskeletal pain, and joint instability. Cardiovascular symptoms, such as lightheadedness and palpitations, and types of dysautonomia, including postural orthostatic tachycardia syndrome (POTS), are frequently reported in adults with hEDS and have been shown to negatively impact quality of life (QoL).

OBJECTIVE

This brief review will be an overview of co-occurring symptoms in POTS and hEDS to inform potential cardiovascular screening procedures.

RESULTS

While many patients with hEDS report cardiovascular symptoms, few have structural abnormalities, suggesting that dysautonomia is likely responsible for these symptoms. One validated screening measure for dysautonomia symptom burden is the Composite Autonomic Symptom Scale (COMPASS-31). Studies have found that adults with POTS, hEDS, and both POTS and hEDS have higher COMPASS-31 scores than the general population, suggesting a high symptom burden due to dysautonomia, which leads to impaired QoL.

CONCLUSION

While studies have examined cardiovascular symptoms and the impact of dysautonomia in adults with and without hEDS, there is scant literature on dysautonomia in pediatric patients with hEDS. Therefore, more studies on cardiovascular symptoms and dysautonomia, as they relate to the quality of life in pediatric patients with hEDS, are needed. This brief review summarizes the current literature on dysautonomia and cardiovascular symptoms in pediatric and adult populations with hEDS.

Sociodemographic Factors, Nutritional Status, and Inflammatory Markers in Patients with Postural Orthostatic Tachycardia Syndrome

Objectives. Postural orthostatic tachycardia syndrome (POTS) is characterized by cardiovascular autonomic dysfunction of unknown etiology with high a prevalence of gastrointestinal symptoms. The aim of the present study was to examine sociodemographic, lifestyle, and nutritional factors as well as inflammatory markers in patients with POTS. Materials and Methods. Forty-three patients with POTS and 61 healthy controls completed questionnaires about sociodemographic factors, lifestyle habits, and gastrointestinal symptoms. Blood samples were analyzed for serum levels of cobalamins, folic acid, iron, total iron-binding capacity (TIBC), ferritin, sodium, potassium, magnesium, phosphorus, albumin, high-sensitive C-reactive protein (CRP), and 25-hydroxyvitamin D (25-OH vitamin D). Results. POTS patients were predominantly women with a lower education level and were more often working part-time, on sick leave, and living alone compared with healthy controls. They reported lower alcohol intake and physical activity levels than controls. The nutrient intake was in general similar in both groups, but POTS patients had a higher intake of different drinks and reported more gastrointestinal symptoms than controls. POTS was associated with higher CRP levels (β: 1.370; 95% CI: 0.004–2.737; $p=0.049$ ), lower albumin levels (β: -1.443; 95% CI: -2.648–(-0.238); $p=0.019$ ), and higher sodium levels (β: 1.392; 95% CI: 0.559–2.225; $p=0.001$ ). Abdominal pain ( $p=0.004$ ) and intestinal symptoms’ influence on daily life ( $p=0.025$ ) were negatively associated with albumin levels. Abdominal pain ( $p=0.011$ ), vomiting and nausea ( $p=0.003$ ), and intestinal symptoms’ influence on daily life ( $p=0.026$ ) were associated with higher sodium levels. Serum levels representing iron and vitamin metabolism were equal between groups. Conclusions. POTS is associated with poorer sociodemographic status, but malnutrition cannot explain POTS or related gastrointestinal symptoms. Higher CRP and lower albumin levels suggest low-grade inflammation as one possible etiological factor.

A Case Study of Successful Application of the Principles of ME/CFS Care to an Individual with Long COVID

Persistent fatigue is one of the most common symptoms of post-COVID conditions, also termed long COVID. At the extreme end of the severity spectrum, some individuals with long COVID also meet the criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), raising the possibility that symptom management approaches for ME/CFS may benefit some long COVID patients. We describe the long-term outcomes of a 19-year-old male who developed profound impairment consistent with ME/CFS after a SARS-CoV-2 infection early in the pandemic. We evaluated and treated him using our clinic’s approach to ME/CFS. This included a history and physical examination that ascertained joint hypermobility, pathological reflexes, physical therapy maneuvers to look for a range of motion restrictions in the limbs and spine, orthostatic testing, and screening laboratory studies. He was found to have profound postural tachycardia syndrome, several ranges of motion restrictions, and mast cell activation syndrome. He was treated according to our clinic’s guidelines for managing ME/CFS, which included manual physical therapy maneuvers and both non-pharmacologic measures and medications directed at postural tachycardia syndrome and mast cell activation. He experienced significant improvement in his symptoms over 30 months. His case emphasizes how the application of the principles of treating ME/CFS has the potential to provide a direction for treating long COVID.

Dysautonomia in COVID-19 Patients: A Narrative Review on Clinical Course, Diagnostic and Therapeutic Strategies

Introduction

On March 11, 2020, the World Health Organization sounded the COVID-19 pandemic alarm. While efforts in the first few months focused on reducing the mortality of infected patients, there is increasing data on the effects of long-term infection (Post-COVID-19 condition). Among the different symptoms described after acute infection, those derived from autonomic dysfunction are especially frequent and limiting.

Objective

To conduct a narrative review synthesizing current evidence of the signs and symptoms of dysautonomia in patients diagnosed with COVID-19, together with a compilation of available treatment guidelines.

Results

Autonomic dysfunction associated with SARS-CoV-2 infection occurs at different temporal stages. Some of the proposed pathophysiological mechanisms include direct tissue damage, immune dysregulation, hormonal disturbances, elevated cytokine levels, and persistent low-grade infection. Acute autonomic dysfunction has a direct impact on the mortality risk, given its repercussions on the respiratory, cardiovascular, and neurological systems. Iatrogenic autonomic dysfunction is a side effect caused by the drugs used and/or admission to the intensive care unit. Finally, late dysautonomia occurs in 2.5% of patients with Post-COVID-19 condition. While orthostatic hypotension and neurally-mediated syncope should be considered, postural orthostatic tachycardia syndrome (POTS) appears to be the most common autonomic phenotype among these patients. A review of diagnostic and treatment guidelines focused on each type of dysautonomic condition was done.

Conclusion

Symptoms deriving from autonomic dysfunction involvement are common in those affected by COVID-19. These symptoms have a great impact on the quality of life both in the short and medium to long term. A better understanding of the pathophysiological mechanisms of Post-COVID manifestations that affect the autonomic nervous system, and targeted therapeutic management could help reduce the sequelae of COVID-19, especially if we act in the earliest phases of the disease.

Impact of Comorbidities on the Prognosis of Pediatric Postural Tachycardia Syndrome

OBJECTIVE

To investigate the influence of comorbidities on the prognosis of pediatric postural tachycardia syndrome (POTS).

METHODS

In this retrospective cohort study, 275 children with POTS admitted to the Department of Pediatrics at Peking University First Hospital were recruited from 2016 to 2019 and followed up. The participants were divided into simple POTS (S-POTS, n=156 cases) and POTS with comorbidities (Co-POTS, n=119 cases) groups according to whether they were complicated with comorbidities. A Cox regression analysis was used to identify the prognostic risk factors for children with POTS, while Kaplan-Meier curves were applied to compare the cumulative symptom remission rate (CSRR) between the two groups. The rehospitalization of the children between the two groups was also compared to explore the influence of comorbidities.

RESULTS

Twenty-one participants (7.6%) were lost during a median follow-up of 24 months. The Cox regression model showed that comorbidities and body mass index (BMI) were associated with the CSRR of the children with POTS. The CSRR of pediatric POTS alone was 1.748 times higher than that of patients with comorbidities, and the CSRR was decreased by 5.1% for each 1 kg/m2 increase in BMI. The most common comorbidity in children with POTS in this study was allergic disorders, followed by the psychological diseases. The patients in the Co-POTS group had a lower CSRR than those in the S-POTS group (log rank P=0.0001). In addition, compared with those of the S-POTS group, the total number of rehospitalizations was high (P=0.001), and the total hospital stays were long in the Co-POTS group (P<0.001).

CONCLUSION

Complicating with comorbidities, pediatric patients with POTS had lower CSRR and more rehospitalizations than those without comorbidities. More attention should be given to comorbidities when managing pediatric POTS.

Dysautonomia in the Ehlers-Danlos syndromes and hypermobility spectrum disorders-With a focus on the postural tachycardia syndrome

Dysautonomia (autonomic dysfunction) occurs in the Ehlers-Danlos syndromes (EDS) and hypermobility spectrum disorders (HSD). Symptoms include palpitations, dizziness, presyncope, and syncope, especially when standing upright. Symptoms of orthostatic intolerance are usually relieved by sitting or lying and may be exacerbated by stimuli in daily life that cause vasodilatation, such as food ingestion, exertion, and heat. Neurocardiovascular dysautonomia may result in postural tachycardia syndrome (PoTS), a major cause of orthostatic intolerance. It is defined by a rise in heart rate of >30 beats per minute (bpm) in adults and >40 bpm in teenagers while upright, without a fall in blood pressure (BP; orthostatic hypotension). In some, it can be compounded by the presence of low BP. For many, there is delay in clinicians recognizing the nature of the symptoms, and recognizing EDS or HSD, leading to delays in treatment. The onset of PoTS may be linked to an event such as infection, trauma, surgery, or stress. Gastrointestinal and urinary bladder involvement may occur, along with thermoregulatory dysfunction. In some, the mast cell activation syndrome may be contributary, especially if it causes vasodilatation. This paper reviews neurocardiovascular dysautonomia with an emphasis on PoTS, its characteristics, associations, pathophysiology, investigation, and treatment.