Boosting the blood pressure benefit of CPAP for people with obstructive sleep apnea

A Cohort Study on Increasing Blood Pressure Benefits in Sleep Apnea Patients After CPAP Treatment

This project will test whether CPAP lowers blood pressure more in some adults with obstructive sleep apnea and whether adding a short sleep medication for people who wake up at night improves that blood pressure effect.

Quick facts

• Study type: Observational
• Enrollment: 200 (estimated)
• Ages: 18 Years to 70 Years
• Sex: All
• Sponsor: Beijing Anzhen Hospital (Academic / other)
• Locations: 1 site (Beijing, Beijing Municipality)
• Trial ID: NCT07357272 on ClinicalTrials.gov

What this trial studies

This is an observational cohort of adults aged 18–70 with diagnosed obstructive sleep apnea who have elevated or uncontrolled office blood pressure. Participants will receive CPAP and be followed with standard polysomnography-confirmed diagnosis and repeated office blood pressure measurements to track changes over time. The study will look for clinical and sleep-related characteristics that predict larger blood pressure reductions with CPAP. It will also compare outcomes in people who use an additional sleep-promoting medication for fragmented sleep versus those who do not to see if improved sleep continuity enhances the BP response.

Who should consider this trial

Good fit: Adults 18–70 with polysomnography-diagnosed obstructive sleep apnea who have snoring, gasping, or daytime sleepiness and elevated office blood pressure (prehypertension, newly diagnosed mild hypertension, or uncontrolled on 1–2 antihypertensive medications).

Not a fit: People without obstructive sleep apnea, those outside the 18–70 age range, those with severe uncontrolled hypertension or multiple high cardiovascular risk factors, or those already at target blood pressure are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, the findings could help clinicians predict who will get meaningful blood pressure reductions from CPAP and whether adding a short sleep aid can increase that benefit, enabling more individualized treatment.

How similar studies have performed: Prior randomized trials of CPAP have shown modest average blood pressure reductions with larger effects in adherent patients and in more severe OSA, but using sleep medications specifically to boost CPAP's blood pressure effect is less well studied.

Eligibility criteria

Inclusion Criteria:

1. Age between 18 and 70 years old;
2. Diagnosed with obstructive sleep apnea (OSA) through overnight polysomnography (PSG), as follows: (1) AHI ≥ 5 times/hour and one of the following conditions is met: (1) The patient complains of daytime sleepiness, lack of sleepiness during sleep, fatigue or insomnia; (2) Waking up due to breathlessness or wheezing; (3) The bed partner or other witnesses report that the patient has habitual snoring, breathing interruptions or both during sleep. Or (2) AHI ≥ 15 times/hour.
3. Satisfy any of the following blood pressure conditions: (1) Office blood pressure 120-139/80-89 mmHg, with ≤ 2 cardiovascular risk factors; (2) Newly diagnosed blood pressure 140-159/90-99 mmHg and without cardiovascular risk factors; (3) Currently taking stable types and doses of antihypertensive drugs, but the office blood pressure has not reached the normal blood pressure standard (120/80 mmHg) with a low-risk level of cardiovascular risk for patients with hypertension; (4) Any non-cardiovascular risk level high-risk patient who voluntarily requests three-month CPAP treatment and accepts follow-up;
4. Able to tolerate 24-hour ambulatory blood pressure monitoring and continuous blood pressure monitoring;

Exclusion Criteria:

1. Previously diagnosed with OSA and currently undergoing OSA treatment (such as CPAP, orthodontic devices, surgery, etc.);
2. Secondary hypertension caused by other reasons other than OSA, such as renal artery stenosis, kidney disease, Cushing's syndrome, primary aldosteronism;
3. Unstable condition (having experienced cardiovascular events or major surgeries in the past 3 months, severe sleepiness (ESS ≥ 16 points), or cognitive impairment that makes it impossible to cooperate, active mental illness or drug/alcohol abuse);
4. Rheumatic immune diseases and malignant tumors;
5. Large artery diseases (such as giant cell arteritis, arterial dissection, aneurysm, etc.);
6. Diseases that cannot accurately measure blood pressure (such as atrial fibrillation, upper limb vascular diseases);
7. Early-onset familial hypertension;
8. Any prescription or over-the-counter sleep aid (benzodiazepines, non-benzodiazepines, melatonin receptor agonists, trazodone, sedative antipsychotic/antidepressants containing sedative components, OTC containing sedative components) within 4 weeks before enrollment;
9. Allergic or contraindicated to the potential study drugs (trazodone, zopiclone);
10. Pregnant, lactating, or planning to become pregnant;
11. Frequent night shift work (≥ 3 nights/week) or circadian rhythm disorder (diagnosed by a doctor);
12. Participating in other interventional clinical trials.

Where this trial is running

Beijing, Beijing Municipality

• Anzhen Hospital, Capital Medical University — Beijing, Beijing Municipality, China (Recruiting)

Study contacts

• Study coordinator: Jiang Xie, M.D.

Conditions Hypertension; Sleep Apnea Syndrome, Obstructive