NCT05237505 · University of California, San Diego
The Cardiovascular Consequences of Sleep Apnea Plus COPD (Overlap Syndrome)
(CRESCENDO-SLP)
What this study is about
Major progress has been made in the area of cardiovascular disease, but we believe that further progress will involve mechanistically addressing underlying respiratory causes including chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA). The most common cause of death in COPD is cardiovascular, although mechanisms are unknown.
View original scientific description
Major progress has been made in the area of cardiovascular disease, but we believe that further progress will involve mechanistically addressing underlying respiratory causes including chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA). The most common cause of death in COPD is cardiovascular, although mechanisms are unknown. OSA has been associated with major neurocognitive and cardiovascular sequelae, the latter likely a function of autonomic nervous system abnormalities, oxidative stress, inflammation, and other pathways. Recent data suggest that individuals with OVS die preferentially of cardiovascular disease compared to OSA or COPD alone, although mechanisms are again unclear. The combination of OSA and COPD may lead to profound hypoxemia. Individuals with COPD can develop pulmonary hypertension via disturbances in gas exchange and parenchymal injury leading to loss of pulmonary vasculature. OSA has been associated with mild to moderate pulmonary hypertension, but the situation may be worse if combined with parenchymal lung disease. The biological response to sustained hypoxemia has been carefully studied as has the topic of intermittent hypoxemia; however, to our knowledge, very little research has occurred regarding the combination of sustained plus intermittent hypoxia as seen in OVS. For example, we do not really know whether individuals with OVS develop coronary disease, right or left heart failure, dysrhythmias or some combination of abnormalities predisposing them to cardiovascular death. Thus, design of interventional studies is challenging as causal pathways are poorly understood despite our considerable preliminary data addressing these issues. The purpose of this study is to examine vascular mechanisms in individuals with COPD/OSA overlap syndrome (OVS) compared with matched individuals with obstructive sleep apnea (OSA) alone or chronic obstructive pulmonary disease (COPD) alone and to perform a phase II pilot mechanistic clinical trial in OVS to examine the effect size of nocturnal bi-level positive airway pressure (PAP) vs. nocturnal oxygen therapy in cardiovascular outcomes.
Interventions
DEVICE
bi-level positive pressure non invasive ventilation
Participants randomized to the bi-level arm will be provided with an auto bi-level device that automatically delivers the required pressure. The settings in the auto bi-level will be minimum EPAP of 4 cmH2O, maximum IPAP of 24 cmH2O, and a range of pressure support between 6-10 cmH2O. For those participants who have been randomized to the bi-level group but have not successfully acclimated to the device with the automatic bi-level settings, we will conduct an in-lab titration of the bi-level therapy during the optional Overnight visit 2.
DRUG
Oxygen gas
The dose of nocturnal oxygen in all participants in the oxygen therapy arm will be 2 liters/minute. Patients with daytime hypoxemia, measured as sustained desaturations below 89% during wake time and/or arterial blood PO2 ≤ 55 mmHg, will be excluded from this study (as specified in the exclusion criteria) for ethical reasons since withholding oxygen in hypoxemic patients would be at odds with standard of care.
Primary outcome measures
Right ventricular mass
Time frame: 6 Months
Cardiac magnet resonance imaging (CMRI): All subjects will undergo cardiac MRI measurements the same day they undergo the evaluation of vascular reactivity measurements. Supine cardiac MRI imaging will be performed using a 3T MR scanner (GE 750, GE Healthcare) with a 16-element cardiac coil for radiofrequency signal reception. Non-invasive blood pressure will be monitored during cardiac MRI scanning (Dinemap). Standard and novel MRI sequences will be used for myocardial tissue characterization, assessment of ventricular function, pulmonary hemodynamics, and aortic compliance
Reactive Hyperemia Index
Time frame: 6 months
Based on a device called EndoPAT, which measures non-invasively bloodflow before, during, and after 5-minutes of occlusion to one arm.
5th generation troponin
Time frame: 6 months
Troponin will be measured from participant serum samples. Troponin is a marker of myocardial injury.
MiR-210
Time frame: 6 months
MicroRNA-210 will be measured from participant serum samples. miR210 may predict risk of atherosclerosis and changes in levels may give insight into mechanisms of our interventions
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Provision of signed and dated informed consent form.
- Stated willingness to comply with all study procedures and availability for the duration of the study.
- Persons aged 40-79.
- For women, only postmenopausal women will be included
- Diagnosed with untreated moderate to severe obstructive sleep apnea (apnea-hypopnea index ≥15 events/hr and ≤80 events/hr) and/or diagnosed with COPD with FEV1/FVC ratio \<0.7 and will be on stable medications as assessed by a board-certified pulmonologist.
Exclusion criteria
- Premenopausal women (i.e. women are pregnant or may become pregnant) or lactation
- Presence of specific devices: cardiac implantable electronic device (CIED) such as pacemakers, implantable cardioverter defibrillators (ICDs) and cardiac resynchronization therapy (CRT) devices, metallic foreign bodies, implantable neurostimulation systems, cochlear implants/ear implant, drug infusion pumps (insulin delivery, analgesic drugs, or chemotherapy pumps), metallic fragments such as bullets, shotgun pellets, and metal shrapnel , cerebral artery aneurysm clips, magnetic dental implants, and artificial limb.
- Known allergic reactions to components of the study intervention: (if getting contrast, MRI contrast (gadolinium)).
- Concurrent severe sleep disorders (such as periodic limb movements, restless legs syndrome, narcolepsy, idiopathic hypersomnia, etc).
- Exhibit Cheyne-Stokes respiration or central sleep apnea (\> 25 % of events central)
- Take potentially confounding medications or hormones that affect breathing.
- Subjects will be excluded if they are deemed medically unstable with active neurological, cardiac, liver, endocrine, and infectious diseases.
- We will also exclude participants with pulmonary disease apart from COPD.
- We will exclude participants with active cancer treatment.
- We will exclude azotemia (estimated glomerular fraction rate \< 30ml/min) as there is some concern about giving gadolinium to these patients (if getting contrast MRI).
- people with exposures deemed to be problematic for the research e.g. any smoking in bedroom by participant or household member, major second-hand smoke, e-cigarettes, tetrahydrocannabinol, major drug or alcohol consumption (\>3 oz/day) and other environmental pollution effects (indoor and outdoor).
- Individuals who are already on continuous O2 for COPD or PAP treatment for OSA.
- Patients with sustained desaturations below 89% during wake time will be excluded for ethical reasons since withholding oxygen in hypoxemic patients would be at odds with standard of care.
- Individuals with OSA (AHI range 15-80/hr) will be screened for pathological sleepiness and will be excluded if ESS \>18/24, history of motor vehicle accident or near miss accident, or high-risk occupation.
- COPD individuals with arterial PCO2 higher than 52 mmHg will be excluded.
- Individuals who are currently incarcerated.
Where
- La Jolla, California
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 3, 2026 · Source of record for eligibility and locations