TOPLINE

Patients with comorbid insomnia and obstructive sleep apnea (COMISA) experienced a significantly larger reduction in 24‑hour systolic blood pressure (SBP) after 4 weeks of continuous positive airway pressure (CPAP) therapy than those with obstructive sleep apnea (OSA) alone. Baseline insomnia was independently associated with a clinically meaningful reduction in 24‑hour SBP. 

METHODOLOGY

• Researchers conducted a prospective cohort study at a tertiary hospital in China to compare the BP-lowering effect of CPAP therapy between patients with COMISA and those with OSA alone.
• They analyzed 71 adult patients (mean age, 40.9 years; 93% men) with newly diagnosed, treatment-naive OSA and either newly identified elevated BP or grade 1 hypertension; none of the patients were scheduled to start antihypertensive medication.
• Insomnia was diagnosed if patients reported clinically significant symptoms — difficulty falling asleep, staying asleep, or early-morning awakening — at least 3 nights per week for at least 3 months, accompanied by daytime dysfunction despite adequate opportunity to sleep.
• All patients completed 4 weeks of auto-CPAP therapy and were classified into COMISA (n = 22) and OSA-alone (n = 49) groups based on standard criteria. Good CPAP adherence was defined as using the device on more than 70% of days, with over 4 hours of use per night on days it was used.
• The primary outcome was a clinically meaningful reduction in 24-hour SBP — defined as a decrease of ≥ 5 mm Hg — based on in-hospital 24-hour ambulatory BP monitoring at baseline and after 4 weeks.

TAKEAWAY

• After 4 weeks of CPAP therapy, the COMISA group had a significantly greater reduction in 24-hour SBP than the OSA-alone group (-6.0 mm Hg vs -0.3 mm Hg; P = .002).
• Baseline insomnia symptoms were independently associated with achieving a clinically meaningful 24-hour SBP reduction in the fully adjusted model, which accounted for potential confounders such as baseline BP, the apnea-hypopnea index, lowest oxygen saturation, and CPAP adherence (adjusted odds ratio, 5.62; P = .011).
• Among patients with good CPAP adherence, those with COMISA still had a significantly greater 24-hour SBP reduction than those with OSA alone (P = .026).

IN PRACTICE

“This study demonstrates that CPAP provides superior BP reduction in COMISA vs OSA alone, supporting personalized management. The pronounced benefit in sleep maintenance symptoms suggests that ameliorating respiratory-driven sleep fragmentation may be a key mechanism,” the authors wrote. 

SOURCE

The study was led by Shuang Li, MD, Beijing Anzhen Hospital, Capital Medical University, Beijing, China. It was published online on July 31, 2026, in CHEST.

LIMITATIONS

The study was conducted at a single hospital with a relatively small sample. The 4‑week follow‑up was not sufficient to assess long‑term cardiovascular outcomes. The researchers also did not systematically exclude insomnia due to other mental or physical conditions nor did they use objective tests such as actigraphy to evaluate circadian rhythm disorders.

DISCLOSURES

The study was funded by the Noncommunicable Chronic Diseases-National Science and Technology Major Project and Beijing Anzhen Hospital High Level Research Funding. The authors disclosed having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.