Abstract
Rationale The impact of treatment for obstructive sleep apnoea (OSA) on reduction of cardiovascular risk is unclear. This study aimed to examine the effect of continuous positive airway pressure (CPAP) on ambulatory blood pressure (BP) and subclinical myocardial injury in subjects with OSA and hypertension.
Methods Subjects with hypertension requiring at least three anti-hypertensive medications and moderate-severe OSA were enrolled. Eligible subjects were randomized (1:1) to receive either CPAP treatment or control (no CPAP) for eight weeks. Changes in ambulatory BP and serum biomarkers were compared. Stratified analysis according to circadian BP pattern was performed.
Main results Ninety two subjects (75% men; age, 51±8 years; apnoea-hypopnoea index 40±8 events·h−1, taking average of 3.4 anti-hypertensive drugs [range 3–6]) were randomised. The group on CPAP treatment, compared to the control group, demonstrated significant reduction in 24-h systolic BP (−4.4 mmHg, 95% CI −8.7 to −0.1, p=0.046), 24-h diastolic BP (−2.9 mmHg, 95% CI −5.5 to −0.2, p=0.032), daytime systolic BP (−5.4 mmHg, −9.7 to −1.0, p=0.016) and daytime diastolic BP (−3.4 mmHg, 95% CI −6.1 to −0.8, p=0.012). CPAP treatment was associated with significant BP lowering only in non-dippers, but not in dippers. Serum troponin I (mean difference −1.74 pg·mL−1, 95% CI −2.97 to −0.5, p=0.006) and brain natriuretic peptide (−9.1 pg·mL−1, 95% CI −17.6 to −0.6, p=0.036) were significantly reduced in CPAP compared to control group.
Conclusion In a cohort with OSA and multiple cardiovascular risk factors including difficult-to-control hypertension, short-term CPAP treatment improved ambulatory BP and alleviated subclinical myocardial injury and strain.
Footnotes
This manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.
Conflict of interest: Dr. Lui has nothing to disclose.
Conflict of interest: Dr. Tse has nothing to disclose.
Conflict of interest: Dr. LAM has nothing to disclose.
Conflict of interest: Dr. Lau reports grants, personal fees and non-financial support from Boerhinger Ingelheim, grants and non-financial support from Pfizer, grants from Sanofi, grants from Amgen, non-financial support from Eisai, outside the submitted work.
Conflict of interest: Dr. Chan has nothing to disclose.
Conflict of interest: M. Ip has nothing to disclose.
- Received September 30, 2020.
- Accepted March 23, 2021.
- Copyright ©The authors 2021. For reproduction rights and permissions contact permissions{at}ersnet.org