Recruiting

CPAP

Sponsor:

Vanderbilt University Medical Center

Code:

NCT05489575

Conditions

Autonomic Failure

Pure Autonomic Failure

Multiple System Atrophy

Parkinson Disease

Supine Hypertension

Eligibility Criteria

Sex: All

Age: 40 - 70+

Healthy Volunteers: Not accepted

Interventions

Active CPAP

Sham CPAP

Sleeping in a head-up tilt (HUT) position

Study Details

Brief summary:

This study aims to learn about the effects of continuous positive airway pressure (CPAP) on people with autonomic failure and high blood pressure when lying down (supine hypertension) to determine if it can be used to treat their high blood pressure during the night. CPAP (a widely used treatment for sleep apnea) involves using a machine that blows air into a tube connected to a mask covering the nose, or nose and mouth, to apply a low air pressure in the airways.

The study includes 3-5 days spent in the Vanderbilt Clinical Research Center (CRC): at least one day of screening tests, followed by up to 3 study days. Subjects may be able to participate in daytime and/or overnight studies. The Daytime study consists of 2 study days: one with active CPAP and one with sham CPAP applied for up to 2 hours. The Overnight study consists of 3 study nights: one with active CPAP, one with sham CPAP, both applied for up to 9 hours and one night sleeping with the bed tilted head-up.

Conditions

Autonomic Failure

Pure Autonomic Failure

Multiple System Atrophy

Parkinson Disease

Supine Hypertension

Study ID

NCT05489575

Start date

Jun 23, 2022

Status verified date

Mar, 2026

Completion date

Aug 31, 2027

Anticipated

Primary completion date

Mar 1, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 40 - 70+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Male and female subjects, age 40-80 years, with autonomic failure including pure autonomic failure, multiple system atrophy and Parkinson disease.
  • Neurogenic orthostatic hypotension, defined as a ≥20-mmHg decrease in systolic blood pressure within 3 minutes of standing associated with impaired autonomic reflexes determined by autonomic testing in the absence of other identifiable causes.
  • Nocturnal supine hypertension (nighttime systolic blood pressure ≥140 mmHg) during the overnight screening for supine hypertension.
  • Patients who are willing and able to provide informed consent

Exclusion Criteria:

  • Patients with history of recent facial trauma or surgery or intolerance to CPAP or to the CPAP mask.
  • Patients who cannot tolerate the medication withdrawal, defined as those who are unable to stand for at least one minute or those with sustained supine blood pressure ≥180/110 mmHg after the medication withdrawal period.
  • Bedridden patients or those who are unable to stand due to motor impairment or severe orthostatic hypotension.
  • Smokers, patients who are pregnant, or have clinically unstable coronary artery disease, or major cardiovascular or neurological event in the past 6 months; heart failure; and other factors which in the investigator's opinion would prevent the subject from completing the protocol including clinically significant abnormalities in clinical or laboratory testing.

Study Design

Enrollment

59 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Active CPAP (Daytime Study)

CPAP at 8, 10, or 12 cm H2O is applied for up to 2 hours while supine and awake.

sham comparator: Sham CPAP (Daytime Study)

Sham CPAP is applied for up to 2 hours while supine and awake.

experimental: Active CPAP (Overnight Study)

CPAP at 8, 10, or 12 cm H2O is applied for up to 9 hours during the night.

sham comparator: Sham CPAP (Overnight Study)

Sham CPAP is applied for up to 9 hours during the night.

active comparator: Sleeping in a head-up tilt position (Overnight Study)

Sleeping with the bed tilted head-up by 10 degrees for up to 9 hours during the night.

Interventions

Active CPAP

Continuous positive airway pressure (CPAP) is applied at 8, 10, or 12 cm H20. The active CPAP level will be determined during a CPAP titration trial

Sham CPAP

Sham continuous positive airway pressure applied at <4 cm H2O

Sleeping in a head-up tilt (HUT) position

Sleeping with the whole bed tilted head-up by 10 degrees or with the head elevated by 13-14 inches.

Primary outcome measure

  • Systolic blood pressure (daytime) [ Time Frame: day 1 and 2 (within 2 hours of the intervention) ]
  • Systolic blood pressure (overnight) [ Time Frame: up to 9 hours during the intervention ]

Central Contacts and Locations

Central contacts

Bonnie K Black, RN, NP

615-343-6862bonnie.black@vumc.org

Luis E Okamoto, MD

615-936-6119luis.e.okamoto@vumc.org

Locations

Autonomic Dysfunction Center/ Vanderbilt University Medical Center

Recruiting

Nashville, Tennessee, United States, 37232

Contacts

Bonnie K Black, RN, NP

615-343-6862bonnie.black@vumc.org

Luis E Okamoto, MD

(615) 936-6119luis.e.okamoto@vumc.org

Principal Investigator:

Italo Biaggioni, MD

More Information

Sponsor

Vanderbilt University Medical Center

Last update posted

Apr 7, 2026

Last verified

Mar, 2026

Keywords

  • CPAP
  • Hypertension
  • Orthostatic hypotension

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Vanderbilt University Medical Center on 2026-04-07.