Autoimmune Investigation for POTS

Recruiting at 1 trial location

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Vanderbilt University Medical Center

Must not be taking: Chronic medications

Disqualifiers: Hypertension, Cardiovascular disease, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 3

58 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but it mentions that any underlying disease requiring regular medication that could affect the study might exclude you from participating. It's best to discuss your specific medications with the trial coordinators.

What data supports the effectiveness of the treatment for POTS?

The research highlights that autonomic function tests, such as those used in the trial, are valuable tools for diagnosing and understanding autonomic disorders like POTS. These tests help identify autonomic dysfunction, which is crucial for tailoring treatment and improving patient outcomes. ^{1 2 3 4 5}

Is autonomic testing safe for humans?

Autonomic testing, which includes various noninvasive tests like heart rate variability and sudomotor function assessments, is generally considered safe and is widely used in clinical settings to evaluate the autonomic nervous system. ^{2 4 6 7 8}

How does this treatment for POTS differ from other treatments?

This treatment is unique because it investigates the role of autoantibodies (proteins that mistakenly target and react with a person's own tissues) against specific receptors in the body, which may contribute to POTS. Unlike standard treatments that focus on managing symptoms, this approach targets the underlying autoimmune component of the condition. ^{9 10 11 12 13}

What is the purpose of this trial?

This trial is studying whether certain immune proteins are causing or worsening symptoms in people with POTS, a condition that makes it hard for them to stand without feeling dizzy or faint. The researchers will study people with POTS to see if these proteins are more common in those with the condition and if these levels vary.

Research Team

Luis E Okamoto, MD

Principal Investigator

Vanderbilt University Medical Center

Eligibility Criteria

This trial is for people aged 18-50 with Postural Tachycardia Syndrome (POTS), which causes a rapid heartbeat upon standing. Participants must have had symptoms for over 6 months and be able to follow the study's procedures. Pregnant individuals, those with recent heart issues or significant arrhythmias, liver or kidney problems, low hematocrit levels, uncontrolled hypertension, serious neurological diseases, or immune/hematological disorders cannot join.

Inclusion Criteria

My heart rate increases significantly when I stand up, without a drop in blood pressure, and this has been happening for more than 6 months.

The subject must understand and be able to comply with the study procedures and restrictions.

Able and willing to provide informed consent

Exclusion Criteria

Pregnancy

My blood pressure is higher than 150/100 mmHg.

I have not had a heart attack, severe chest pain, serious irregular heartbeat, deep vein thrombosis, or lung blood clots in the last 6 months.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Autonomic and Antibody Assessments

Participants undergo various tests to assess autonomic function and detect autoantibodies to adrenergic receptors

Up to 3 study days

Up to 3 visits (in-person)

Follow-up

Participants are monitored for the stability of autoantibody levels over time

4 weeks

Treatment Details

Interventions

• 24-hour heart rhythm and blood pressure monitoring
• Assessment of splanchnic capacitance
• Autonomic function tests
• isoproterenol
• microneurography
• phenylephrine
• Quantitative Axonal Sudomotor Reflex Testing
• Rebreathing test

Trial Overview The study tests if autoantibodies against autonomic nervous system receptors are present in POTS patients and affect their symptoms. It includes various diagnostic tests like microneurography, blood pressure monitoring over 24 hours, posture studies with blood samples involving minimal radiation exposure, and autonomic function assessments.

Participant Groups

Group I: Autonomic and Antibody Assessments Experimental Treatment 10 Interventions

On up to 3 study days, POTS patients and control subjects will have several tests to assess autonomic function and to detect the presence of autoantibodies to adrenergic receptors. The following tests will de done but in some participants it may not be necessary to do all of them. The investigator will discuss with each participant which particular tests will be done in each particular case: * Posture study with blood samples for autoantibody testing * 24-hour heart rhythm and blood pressure monitoring * autonomic function tests * Quantitative Axonal Sudomotor Reflex Testing * Total blood volume assessment * Pharmacologic testing with phenylephrine * Pharmacologic testing with isoproterenol * Cardiac output with rebreathing * Assessment of splanchnic capacitance * Microneurography

Who Is Running the Clinical Trial?

Vanderbilt University Medical Center

Lead Sponsor

Trials

922

Recruited

939,000+

University of Oklahoma

Collaborator

Trials

484

Recruited

95,900+

References

1. Netherlands pubmed.ncbi.nlm.nih.gov

Electrodiagnostic assessment of the autonomic nervous system: A consensus statement endorsed by the American Autonomic Society, American Academy of Neurology, and the International Federation of Clinical Neurophysiology. [2021]

2. Netherlands pubmed.ncbi.nlm.nih.gov

Testing the autonomic nervous system. [2021]

3. United States pubmed.ncbi.nlm.nih.gov

Disorders of the autonomic nervous system: Part 2. Investigation and treatment. [2004]

4. United States pubmed.ncbi.nlm.nih.gov

Quantitative studies of autonomic function. [2005]

5. France pubmed.ncbi.nlm.nih.gov

[Cardiovascular autonomic reflexes on the postural orthostatic tachycardia syndrome]. [2009]

6. United States pubmed.ncbi.nlm.nih.gov

Autonomic testing: common techniques and clinical applications. [2014]

7. United States pubmed.ncbi.nlm.nih.gov

Auxiliary Tests of Autonomic Functions. [2023]

8. United States pubmed.ncbi.nlm.nih.gov

Testing the autonomic nervous system. [2022]

9. United States pubmed.ncbi.nlm.nih.gov

Association of autoantibodies to muscarinic acetylcholine receptors with gastrointestinal symptoms and disease severity in patients with postural orthostatic tachycardia syndrome. [2022]

10. Netherlands pubmed.ncbi.nlm.nih.gov

A functional cell-based bioassay for assessing adrenergic autoantibody activity in postural tachycardia syndrome. [2022]

11. United States pubmed.ncbi.nlm.nih.gov

Low-level tragus stimulation improves autoantibody-induced hyperadrenergic postural tachycardia syndrome in rabbits. [2023]

12. Netherlands pubmed.ncbi.nlm.nih.gov

Long-term cardiovascular autonomic and clinical changes after immunoglobulin G immunoadsorption therapy in autoimmune autonomic ganglionopathy. [2018]

13. Switzerland pubmed.ncbi.nlm.nih.gov

Inflammatory Biomarkers in Postural Orthostatic Tachycardia Syndrome with Elevated G-Protein-Coupled Receptor Autoantibodies. [2021]