Sleep ApneaNCT04575740

Phenotyping Mechanistic Pathways for Adverse Health Outcomes in Sleep Apnea

A study testing PAP in people with Sleep Apnea, run by Brigham and Women's Hospital at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Trial summary

Obstructive sleep apnea (OSA) is a highly prevalent disorder with adverse neurocognitive and cardio-metabolic outcomes. Continuous positive airway pressure (CPAP) is the gold standard therapeutic option to treat airway obstructions during sleep and thus, prevent its adverse cardiovascular and neurocognitive outcomes. Read more about this study

Who is it for?: Ages 21 to 80 years
Conditions the study is for: Sleep Apnea
What is being tested?: PAP
Type of treatment: Medical device
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 209 participants
Where: 1 siteUnited States
Study dates: 10 Sep 2020to 30 Sep 2025
Phase: Interventional
Are there results?: None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 21 to 80 years
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Adults aged 21-80 years.
Participants with a previous diagnosis of moderate to severe obstructive sleep will be eligible to enroll and attend the baseline study. Patients with a total apnea-hypopnea index greater than 15 events/hr on the baseline study will be eligible for further participation.

Who cannot join

Current treatment for obstructive sleep apnea (including CPAP, oral appliances, supplemental oxygen). Patients must be untreated prior to the baseline visit.
Use of medications that might depress respiration (including opioids, barbiturates, benzodiazepines, and Z drugs, including zolpidem, zopiclone, eszopiclone, and zaleplon).
Active use of non-prescription opioids (e.g., cocaine, methamphetamine)
Uncontrolled medical problem or major organ system disease, which, in the opinion of the investigators (PI and Co-Is), would interfere with the evaluation of the subject (e.g., uncontrolled hypertension, unstable coronary heart disease, etc.).
History of congestive heart failure, renal insufficiency, systemic neurological condition that could affect respiration.
Sleep disordered breathing or respiratory disorders other than obstructive sleep apnea:

Show all 12Show fewer

central sleep apnea (>50% of respiratory events scored as central),
chronic hypoventilation/hypoxemia (awake SaO2 < 92% by oximetry) due to chronic obstructive pulmonary disease or other respiratory conditions.
Other sleep disorders: periodic limb movements (periodic limb movement arousal index > 10/hr), narcolepsy, or parasomnias.
Patients unable or unwilling to use CPAP.
Insomnia or insufficient sleep (self-reported inability to sleep >6 hrs night).
Pregnancy (women)

Trial locations and contacts

1 site in 1 country.

United States1 site

Brigham and Women's Hospital
Boston, Massachusetts, 02115

Other trials in United States

About this study

One of the main limitations of these trials may be the inadequate characterization of OSA and its acute physiological consequences. By characterizing OSA based on the "apnea-hypopnea index (AHI)", there is a potential risk of negative results.

In this trial, the investigators intend to tackle this issue, by better characterization of OSA-related physiological consequences during sleep using physiologically driven metrics to capture the burden of OSA-related hypoxemia ("hypoxic burden"), autonomic response ("heart rate burden"), and sleep fragmentation ("arousal burden").

Conditions: Sleep Apnea
Being tested: PAP
Keywords: Sleep apnea, Hypoxic burden, Arousal intensity, Post-event tachycardia, Positive airway pressure, Apnea hypopnea index
Medical subject headings: Sleep Apnea Syndromes

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

PAPDevice
Positive airway pressure to treat sleep apnea

Study groups in NCT04575740
Study group	Role	What they receive
Positive Airway Pressure Device	Experimental	All participants will receive PAP therapy Receives: Device: PAP

What is being measured

The primary outcome is the main question the study is designed to answer.

Change from baseline flow-mediated vasodilation at 12 weeks
Flow mediated vasodilation is studied using high resolution ultrasound of the artery.
Measured: 12 weeks
Change from baseline 24-hour mean systolic blood pressure at 12 weeks
Mean systolic blood pressure over a 24-hour period is measured using an ambulatory blood pressure monitor.
Measured: 12 weeks
Change from baseline Epworth Sleepiness Scale (ESS) at 12 weeks
Self-reported sleepiness measured using the Epworth Sleepiness Scale (units on a scale). Values range from 0-24; higher values indicate greater sleepiness.
Measured: 12 weeks

Secondary outcomes (22)

Change from baseline F2-Isoprostane/Creatinine Ratio at 12 weeks
F2-Isoprostane/Creatinine Ratio, a measure of oxidative stress, is calculated from urine sample.
Measured: 12 weeks
Change from baseline Albumin/Creatinine Ratio at 12 weeks
Urinary Albumin/Creatinine Ratio is calculated from urine samples.
Measured: 12 weeks
Change from baseline Albumin without Creatinine at 12 weeks
Urinary Albumin is calculated from urine samples.
Measured: 12 weeks
Change from baseline Oxidized low-density lipoprotein (LDL) at 12 weeks
Oxidized low-density lipoprotein measurements are calculated through fasting phlebotomy.
Measured: 12 weeks
Change from baseline N-terminal pro b-type natriuretic peptide (NT-proBNP) at 12 weeks
N-terminal pro b-type natriuretic peptide (NT-proBNP) measurements are calculated through fasting phlebotomy.
Measured: 12 weeks
Change from baseline Hemoglobin A1c (HbA1c) at 12 weeks
Hemoglobin A1c (HbA1c) measurements are calculated through fasting phlebotomy.
Measured: 12 weeks
Change from baseline Plasminogen Activator Inhibitor-1 at 12 weeks
Plasminogen activator inhibitor type 1 (PAI-1) measurements are calculated through fasting phlebotomy.
Measured: 12 weeks
Change from baseline Fibrinogen Antigen at 12 weeks
Fibrinogen Antigen measurements are calculated through fasting phlebotomy. High values indicate inflammation and increased risk of atherosclerosis.
Measured: 12 weeks
Change from baseline Glucose at 12 weeks
Blood glucose measurements are calculated through fasting phlebotomy
Measured: 12 weeks
Change from baseline high sensitivity C-Reactive Protein (hs-CRP) at 12 weeks
C-reactive protein measurements are calculated from blood samples collected through fasting phlebotomy.
Measured: 12 weeks
Change from baseline Interleukin-6 (IL-6) at 12 weeks
IL-6 is calculated from blood samples collected through fasting phlebotomy
Measured: 12 weeks
Change from baseline Creatinine at 12 weeks
Creatinine is calculated from blood samples collected through fasting phlebotomy
Measured: 12 weeks
Change from baseline Cystanin C with eGFR at 12 weeks
Cystanin C with eGFR is calculated from blood samples collected through fasting phlebotomy
Measured: 12 weeks
Change from baseline lipid panel at 12 weeks
Lipid panel measurements are calculated from blood samples collected through fasting phlebotomy.
Measured: 12 weeks
Change from baseline 24-hour mean diastolic blood pressure at 12 weeks
Mean diastolic blood pressure over a 24-hour period is measured using an ambulatory blood pressure monitor.
Measured: 12 weeks
Change from baseline 24-hour mean blood pressure at 12 weeks
Mean arterial blood pressure over a 24-hour period is measured using an ambulatory blood pressure monitor.
Measured: 12 weeks
Change from baseline nocturnal mean systolic blood pressure at 12 weeks
Mean systolic blood pressure during sleep is measured using an ambulatory blood pressure monitor.
Measured: 12 weeks
Change from baseline nocturnal mean diastolic blood pressure at 12 weeks
Mean diastolic blood pressure during sleep is measured using an ambulatory blood pressure monitor.
Measured: 12 weeks
Change from baseline nocturnal mean blood pressure at 12 weeks
Mean arterial blood pressure during sleep is measured using an ambulatory blood pressure monitor.
Measured: 12 weeks
Change from baseline Psychomotor Vigilance Task reaction time at 12 weeks
3-minute Psychomotor Vigilance Tasks will be done to quantify the speed with which subjects respond to a visual stimulus.
Measured: 12 weeks
Change from baseline Psychomotor Vigilance Task lapses per test at 12 weeks
3-minute Psychomotor Vigilance Tasks will be done to quantify the speed with which subjects respond to a visual stimulus.
Measured: 12 weeks
Change from baseline Functional Outcome of Sleep Questionnaire (FOSQ) at 12 weeks
This test will be used to assess the impact of excessive sleepiness on functional outcomes relevant to daily behaviors and sleep-related quality of life.
Measured: 12 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

10 Sep 202030 Sep 2025

First posted5 Oct 2020
Study start10 Sep 2020
Primary completion30 Jun 2025
Study completion30 Sep 2025

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for Sleep ApneaStudies of the same condition, open and under way.
More trials run by Brigham and Women's HospitalThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase N/A
Primary purpose: Diagnosis
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Enrolment: 209 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT04575740
Sponsor's protocol ID: PhenOSA
Other IDs: 1R01HL153874
Status last verified: Aug 2024
First submitted: 16 Sep 2020
Last updated: 16 Dec 2025
Results posted: No
FDA-regulated drug: No
FDA-regulated device: Yes
Individual data sharing: Yes

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

RecruitingObservational study
Locus Coeruleus and CCHS (Congenital Central Hypoventilation Syndrome)
Ondine Syndrome (Congenital Central Hypoventilation Syndrome)
RecruitingObservational study
Development and Validation of a Multimodal Deep Learning Model Using Peripheral Oxygen Saturation and Ballistocardiography Signals for Predicting Apnea-Hypopnea Index in Obstructive Sleep Apnea
Obstructive Sleep Apnea
Not yet recruiting
Comprehensive Opioid Management and Breathing During Sleep
Sleep-Disordered Breathing, Chronic Opioid Use
Recruiting
Janus II Feasibility
Sleep Apnea
RecruitingPhase 3
A Study to Learn About the Monthly Dosing Study Medicine Called Berobenatide in Adults With Breathing Problems During Sleep and Overweight or Obesity Who Do Not Use a Breathing Machine (PAP) (VESPER-OSA 2)
Apnea, Sleep Disorders

All Sleep Apnea trials

Study at a glance

From the registry record, last updated by the sponsor on 16 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Phenotyping Mechanistic Pathways for Adverse Health Outcomes in Sleep Apnea
ClinicalTrials.gov ID: NCT04575740
Acronym / sponsor ID: PhenOSA
Conditions: Sleep Apnea
Keywords: Sleep apnea, Hypoxic burden, Arousal intensity, Post-event tachycardia, Positive airway pressure, Apnea hypopnea index
Study type: Interventional
Recruitment status: Completed
Enrolment: 209 participants (actual)
Lead sponsor: Brigham and Women's HospitalUniversity, hospital or other
Collaborators: National Heart, Lung, and Blood Institute (NHLBI)
Study start: 10 Sep 2020 (actual)
Primary completion: 30 Jun 2025 (actual)
Study completion: 30 Sep 2025 (actual)
First posted: 5 Oct 2020 (actual)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Study design

Primary purpose: Diagnosis
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Number of arms: 1

Arm	Type	Receives
Positive Airway Pressure Device	Experimental	Device: PAPAll participants will receive PAP therapy

Who may qualify

Ages: 21 to 80 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (2 listed)

Adults aged 21-80 years.
Participants with a previous diagnosis of moderate to severe obstructive sleep will be eligible to enroll and attend the baseline study. Patients with a total apnea-hypopnea index greater than 15 events/hr on the baseline study will be eligible for further participation.

Key exclusion criteria (12 listed)

Current treatment for obstructive sleep apnea (including CPAP, oral appliances, supplemental oxygen). Patients must be untreated prior to the baseline visit.
Use of medications that might depress respiration (including opioids, barbiturates, benzodiazepines, and Z drugs, including zolpidem, zopiclone, eszopiclone, and zaleplon).
Active use of non-prescription opioids (e.g., cocaine, methamphetamine)
Uncontrolled medical problem or major organ system disease, which, in the opinion of the investigators (PI and Co-Is), would interfere with the evaluation of the subject (e.g., uncontrolled hypertension, unstable coronary heart disease, etc.).
History of congestive heart failure, renal insufficiency, systemic neurological condition that could affect respiration.

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
PAPPositive airway pressure to treat sleep apnea	Device	Positive Airway Pressure Device

Primary outcome

Change from baseline flow-mediated vasodilation at 12 weeks
Time frame: 12 weeks
Flow mediated vasodilation is studied using high resolution ultrasound of the artery.
Change from baseline 24-hour mean systolic blood pressure at 12 weeks
Time frame: 12 weeks
Mean systolic blood pressure over a 24-hour period is measured using an ambulatory blood pressure monitor.
Change from baseline Epworth Sleepiness Scale (ESS) at 12 weeks
Time frame: 12 weeks
Self-reported sleepiness measured using the Epworth Sleepiness Scale (units on a scale). Values range from 0-24; higher values indicate greater sleepiness.

22 secondary outcomes

Change from baseline F2-Isoprostane/Creatinine Ratio at 12 weeks
Time frame: 12 weeks
Change from baseline Albumin/Creatinine Ratio at 12 weeks
Time frame: 12 weeks
Change from baseline Albumin without Creatinine at 12 weeks
Time frame: 12 weeks
Change from baseline Oxidized low-density lipoprotein (LDL) at 12 weeks
Time frame: 12 weeks
Change from baseline N-terminal pro b-type natriuretic peptide (NT-proBNP) at 12 weeks
Time frame: 12 weeks
Change from baseline Hemoglobin A1c (HbA1c) at 12 weeks
Time frame: 12 weeks
Change from baseline Plasminogen Activator Inhibitor-1 at 12 weeks
Time frame: 12 weeks
Change from baseline Fibrinogen Antigen at 12 weeks
Time frame: 12 weeks
Change from baseline Glucose at 12 weeks
Time frame: 12 weeks
Change from baseline high sensitivity C-Reactive Protein (hs-CRP) at 12 weeks
Time frame: 12 weeks
Change from baseline Interleukin-6 (IL-6) at 12 weeks
Time frame: 12 weeks
Change from baseline Creatinine at 12 weeks
Time frame: 12 weeks
Change from baseline Cystanin C with eGFR at 12 weeks
Time frame: 12 weeks
Change from baseline lipid panel at 12 weeks
Time frame: 12 weeks
Change from baseline 24-hour mean diastolic blood pressure at 12 weeks
Time frame: 12 weeks
Change from baseline 24-hour mean blood pressure at 12 weeks
Time frame: 12 weeks
Change from baseline nocturnal mean systolic blood pressure at 12 weeks
Time frame: 12 weeks
Change from baseline nocturnal mean diastolic blood pressure at 12 weeks
Time frame: 12 weeks
Change from baseline nocturnal mean blood pressure at 12 weeks
Time frame: 12 weeks
Change from baseline Psychomotor Vigilance Task reaction time at 12 weeks
Time frame: 12 weeks
Change from baseline Psychomotor Vigilance Task lapses per test at 12 weeks
Time frame: 12 weeks
Change from baseline Functional Outcome of Sleep Questionnaire (FOSQ) at 12 weeks
Time frame: 12 weeks

Results and safety

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 16 Dec 2025.
Individual participant dataSharing planned: Yes

Related trials for Sleep Apnea

RecruitingObservational study
Locus Coeruleus and CCHS (Congenital Central Hypoventilation Syndrome)
Ondine Syndrome (Congenital Central Hypoventilation Syndrome)
RecruitingObservational study
Development and Validation of a Multimodal Deep Learning Model Using Peripheral Oxygen Saturation and Ballistocardiography Signals for Predicting Apnea-Hypopnea Index in Obstructive Sleep Apnea
Obstructive Sleep Apnea
Not yet recruiting
Comprehensive Opioid Management and Breathing During Sleep
Sleep-Disordered Breathing, Chronic Opioid Use
Recruiting
Janus II Feasibility
Sleep Apnea
RecruitingPhase 3
A Study to Learn About the Monthly Dosing Study Medicine Called Berobenatide in Adults With Breathing Problems During Sleep and Overweight or Obesity Who Do Not Use a Breathing Machine (PAP) (VESPER-OSA 2)
Apnea, Sleep Disorders

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Ali Azarbarzin, PhD principal investigator

Brigham and Women's Hospital

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A study testing PAP in people with Sleep Apnea, run by Brigham and Women's Hospital at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 16 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change from baseline flow-mediated vasodilation at 12 weeks (time frame: 12 weeks). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04575740.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Dec 2025.