The Pathophysiology of Orthostatic Hypotension

Phase 1

Completed

• Conditions: Autonomic Nervous System Diseases; Orthostatic Hypotension; Dopamine Beta-Hydroxylase Deficiency; Orthostatic Intolerance
• Interventions: Procedure: Standing or upright tilt; Procedure: Microneurography; Procedure: QSweat; Device: neck cuff stimulation; Drug: phenylephrine,isoproterenol,nitroprusside,propranolol,edrophonium,atropine,tyramine; Drug: clonidine,yohimbine,metoclopramide,alpha-methyldopa; Procedure: BodPod; Procedure: Eye exam; Procedure: Sleep study; Procedure: Pain response testing; Procedure: Metabolic chamber; Procedure: Brain function studies; Procedure: Bicycle Exercise Test

• Registration Number: NCT00748059
• Lead Sponsor: Vanderbilt University Medical Center

Brief Summary

The purpose of this study is to determine the cause of low blood pressure in selective patients who have problems with their involuntary (autonomic) nervous system. These patients frequently have had symptoms throughout their life, and their disorder might have a genetic basis. The biochemical, physiological and pharmacological procedures in this study should help us define the problem and perhaps lead to more effective treatment.

Detailed Description

Not available

Study Timeline

• Study Start: 1996-12
• Study First Submitted: 2008-09-05
• Study First Submitted QC: 2008-09-05
• Study First Posted: 2008-09-08
• Primary Completion: 2020-12
• Study Completion: 2020-12
• Status Verified: 2021-05
• Last Update Submitted: 2021-05-07
• Last Update Posted: 2021-05-12

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 10

Inclusion Criteria

• severe orthostatic hypotension and other autonomic symptoms but do not meet criteria for standard diagnosis
• non-smokers
• drug-free
• able to give informed consent
• free of pulmonary, renal, hematopoietic, hepatic and cardiac disease

Exclusion Criteria

• medications affecting the autonomic nervous system
• any chronic illness
• anemia (Hct<30)
• women of childbearing age who are pregnant or nursing
• smokers

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
A	Bicycle Exercise Test	Patients with Orthostatic Hypotension
A	Pain response testing	Patients with Orthostatic Hypotension
A	Microneurography	Patients with Orthostatic Hypotension
A	QSweat	Patients with Orthostatic Hypotension
A	clonidine,yohimbine,metoclopramide,alpha-methyldopa	Patients with Orthostatic Hypotension
A	Sleep study	Patients with Orthostatic Hypotension
A	Metabolic chamber	Patients with Orthostatic Hypotension
A	Standing or upright tilt	Patients with Orthostatic Hypotension
A	phenylephrine,isoproterenol,nitroprusside,propranolol,edrophonium,atropine,tyramine	Patients with Orthostatic Hypotension
A	Brain function studies	Patients with Orthostatic Hypotension
A	neck cuff stimulation	Patients with Orthostatic Hypotension
A	BodPod	Patients with Orthostatic Hypotension
A	Eye exam	Patients with Orthostatic Hypotension

Primary Outcome Measures

Name	Time	Method
hemodynamic changes with standing	following test

Secondary Outcome Measures

Name	Time	Method
quantitative sweat testing	2 hours
sympathetic nerve activity	during stimulation of sympathetic nervous system
Eye function	once
Metabolic rate	once
blood and urine hormones	after test
blood volume	during supine and/or upright postures
Pain response	once
Sleep efficiency	once
Responses on questionnaires and computer tasks designed to assess brain function	once

Trial Locations

Locations (1)

Vanderbilt University; 🇺🇸 Nashville, Tennessee, United States