An interventional study of Tests of sympathetic inhibition and Tests of sympathetic activation in Multiple Sclerosis, Control Subjects and Autonomic Dysreflexia, sponsored by Mayo Clinic. Recruiting at 1 site in United States. Open to participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-28.
Sponsored by Mayo Clinic · Not applicable, Interventional, and Diagnostic
This study looks to characterize gradients of dysfunction in the autonomic nervous system in patients with clinically diagnosed multiple sclerosis. The autonomic nervous system plays key roles in regulation of blood pressure, skin blood flow, and bladder health- all issues that individuals with multiple sclerosis typically suffer. Focusing on blood pressure regulation, the most precise metric with broad clinical applicability, the investigators will perform laboratory-based tests to probe the body's ability to generate autonomic responses. For both individuals with multiple sclerosis and uninjured controls, laboratory-based experiments will utilize multiple parallel recordings to identify how the autonomic nervous system is able to inhibit and activate signals. The investigators anticipate that those with autonomic dysfunction with multiple sclerosis will exhibit abnormalities in these precise metrics. The investigators will look to see if any substantial connections exist between different degrees of preserved autonomic function and secondary autonomic complications from multiple sclerosis. In accomplishing this, the investigators hope to give scientists important insights to how the autonomic nervous system works after multiple sclerosis and give physicians better tools to manage these secondary autonomic complications.
Exclusion Criteria:
Diagnostic Test: Tests of sympathetic inhibition · Diagnostic Test: Tests of sympathetic activation · Diagnostic Test: Testing of autonomic dysreflexia
Diagnostic Test: Tests of sympathetic inhibition · Diagnostic Test: Tests of sympathetic activation · Diagnostic Test: Testing of autonomic dysreflexia
Bolus phenylephrine infusion using the Oxford technique will generate the need to inhibit sympathetic activity. Similarly, resting state Mayer waves will be assessed with regard to heart rate and blood pressure responses.
Cold pressor test of the hand will be used to cause sympathetic activation. Valsalva's maneuver will assess the ability to buffer against blood pressure fall (phase II).
Cold pressor test of the foot and bladder pressor response will be tested.
Valsalva Maneuver Phase II
Presence or absence of phase II on Valsalva maneuver testing, which takes approximately 15 seconds to complete. This will be repeated x3.
Time frame: During single laboratory diagnostic testing session, on average 30 minutes after start of laboratory testing session
Beat-to-beat heart rate
Electrocardiogram will record continuous measures with changes in R-R interval (ms) quantified and compared to baseline.
Time frame: Continuous recording during single laboratory diagnostic testing session, from baseline to lab session end, average of 3 hours in duration
Beat-to-beat blood pressure
Non-invasive continuous blood pressure monitors will be used, with changes in systolic and diastolic pressure (in mmHg) from resting baseline measured.
Time frame: Continuous recording during single laboratory diagnostic testing session, from baseline to lab session end, average of 3 hours in duration
Quantify autonomic dysreflexia and orthostatic hypotension
Participants will be given the Autonomic Dysfunction Following Spinal Cord Injury questionnaire (score range 0-436, with higher scores indicating more autonomic dysfunction).
Time frame: Baseline, prior to laboratory diagnostic testing session
Quantify secondary autonomic complications
Participants will be given the Composite Autonomic Symptom Score (range 0-100, with higher scores indicating more autonomic dysfunction).
Time frame: Baseline, prior to laboratory diagnostic testing session
Serum Catecholamines
A series of 3 serum catecholamine draws will occur during the study visit at baseline, pre-pressor test, and post-pressor test to evaluate change in stress hormone.
Time frame: 3x during single laboratory diagnostic testing session - collected at Baseline, pre-pressor test, post-pressor test - pre-pressor & post-pressor timepoint labs collected on average 2.5 & 3 hours post-baseline, respectively
Serum Cortisol
A series of 3 serum cortisol draws will occur during the study visit at baseline, pre-pressor test, and post-pressor test to evaluate change in stress hormone.
Time frame: 3x during single laboratory diagnostic testing session - collected at Baseline, pre-pressor test, post-pressor test - pre-pressor & post-pressor timepoint labs collected on average 2.5 & 3 hours post-baseline, respectively
T-Cell Exhaustion Markers
Blood will be drawn at start of laboratory testing to assess T-cell exhaustion markers by incidence of surface markers including PD-1, TIM-3, LAG3, and CTLA-4 per individual.
Time frame: During single laboratory diagnostic testing session - Baseline
Plan to share: No
No publications or documents are linked to this record.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Mayo Clinic