COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC:

Get the latest research information from NIH: Menu

Overnight Trials With Heat Stress in Autonomic Failure Patients With Supine Hypertension

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT03042988
Recruitment Status : Suspended (Recruitment is temporarily suspended due to COVID-19 outbreak)
First Posted : February 3, 2017
Last Update Posted : April 10, 2020
Information provided by (Responsible Party):
Italo Biaggioni, Vanderbilt University Medical Center

Brief Summary:
Patients with autonomic failure are characterized by disabling orthostatic hypotension (low blood pressure on standing), and at least half of them also have high blood pressure while lying down (supine hypertension). Exposure to heat, such as in hot environments, often worsens their orthostatic hypotension. The causes of this are not fully understood. The purpose of this study is to evaluate whether applying local heat over the abdomen of patients with autonomic failure and supine hypertension during the night would decrease their nocturnal high blood pressure while lying down. This will help us better understand the mechanisms underlying this phenomenon, and may be of use in the treatment of supine hypertension.

Condition or disease Intervention/treatment Phase
Hypertension Pure Autonomic Failure Multiple System Atrophy Autonomic Failure Other: Heating pad Other: Sham control Not Applicable

Detailed Description:

Primary autonomic failure is a neurodegenerative condition characterized by loss of efferent sympathetic function and severe baroreflex impairment. The clinical hallmark of autonomic failure is disabling orthostatic hypotension, but at least half of patients are also hypertensive while lying down. This supine hypertension can be severe and associated with end-organ damage and worsening of orthostatic hypotension due to increased pressure natriuresis. It also complicates the management of these patients by limiting the use of daytime pressor agents for the treatment of orthostatic hypotension. Currently, no antihypertensive drug effectively lowers BP and prevents pressure natriuresis without worsening standing BP.

It is well known that heat exposure (e.g. hot weather or a hot bath or shower) produces an acute and temporary worsening of orthostatic hypotension in autonomic failure patients. Factors that may predispose these patients to the lowering BP effects of heat stress include 1) impaired heat dissipation due to inability to sweat, 2) preserved heat-mediated skin vasodilation, and 3) blunted sympathetic hemodynamic responses to maintain BP (increases in cardiac output, heart rate, and vaso- and venoconstriction). Our preliminary results showed that 2 hours of passive heat stress lowers BP in these patients through a decrease in central volume. In this study, we will assess the efficacy and safety of passive heat stress in the treatment of nocturnal supine hypertension in autonomic failure patients. Our hypothesis is that controlled local (abdominal) passive heat stress applied during the night will lower nocturnal BP in autonomic failure patients with supine hypertension.

To test this hypothesis, we propose to compare the BP effects of passive heat applied during the night vs. a sham control in a randomized crossover study in autonomic failure patients with supine hypertension.

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 20 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Intervention Model Description: randomized, 2-arm crossover study (heat vs sham)
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Overnight Trials to Compare the Effects of Controlled Heat Stress Versus Sham Control on Nocturnal Supine Hypertension in Autonomic Failure Patients
Actual Study Start Date : January 30, 2017
Estimated Primary Completion Date : January 30, 2021
Estimated Study Completion Date : July 30, 2021

Arm Intervention/treatment
Experimental: Heat Stress
Passive heat-stress using a commercial heating pad applied on the trunk
Other: Heating pad
Heat stress applied on the trunk for up to 8 hours
Other Name: Local heat stress

Sham Comparator: Control (Non-heating)
Commercial heating pad applied on the trunk but turned off
Other: Sham control
heating pad turned off applied on the trunk for up to 8 hours
Other Name: control

Primary Outcome Measures :
  1. Systolic blood pressure [ Time Frame: 10 pm - 8 am ]
    Maximal change from baseline in systolic blood pressure during the night, measured from 10 pm to 8 am

Secondary Outcome Measures :
  1. Orthostatic Tolerance the following morning [ Time Frame: 10 min standing ]
    Orthostatic tolerance defined as the area under the curve of standing systolic blood pressure calculated by the trapezoidal rule (upright systolic blood pressure multiplied by standing time) during a 10-minute standing test

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   18 Years to 80 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Male and female patients, between 18-80 yrs., with primary autonomic failure (Parkinson Disease, Multiple System Atrophy, and Pure Autonomic Failure) and supine hypertension. Supine hypertension will be defined as SBP≥150 mmHg.
  • Patients able and willing to provide informed consent.

Exclusion Criteria:

  • Pregnancy
  • Significant cardiac, renal or hepatic illness, or with contraindications to administration of pressor agents or with other factors, which in the investigator's opinion would prevent the subject from completing the protocol including clinically significant abnormalities in clinical, mental or laboratory testing.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03042988

Layout table for location information
United States, Tennessee
Autonomic Dysfunction Center/ Vanderbilt University Medical Center
Nashville, Tennessee, United States, 37232
Sponsors and Collaborators
Vanderbilt University Medical Center
Layout table for investigator information
Principal Investigator: Italo Biaggioni, MD Vanderbilt University Medical Center
Layout table for additonal information
Responsible Party: Italo Biaggioni, Professor of Medicine and Pharmacology, Vanderbilt University Medical Center Identifier: NCT03042988    
Other Study ID Numbers: VR22699
141523 ( Other Identifier: Vanderbilt IRB )
First Posted: February 3, 2017    Key Record Dates
Last Update Posted: April 10, 2020
Last Verified: April 2020
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No
Keywords provided by Italo Biaggioni, Vanderbilt University Medical Center:
supine hypertension
autonomic failure
heat stress
orthostatic hypotension
Additional relevant MeSH terms:
Layout table for MeSH terms
Multiple System Atrophy
Shy-Drager Syndrome
Pure Autonomic Failure
Heat Stress Disorders
Vascular Diseases
Cardiovascular Diseases
Pathological Conditions, Anatomical
Primary Dysautonomias
Autonomic Nervous System Diseases
Nervous System Diseases
Basal Ganglia Diseases
Brain Diseases
Central Nervous System Diseases
Movement Disorders
Neurodegenerative Diseases
Wounds and Injuries