0
Original Research |

Effect of CPAP-withdrawal on blood pressure in OSA: data from three randomized-controlled trials

Esther I. Schwarz, MD; Christian Schlatzer, MD; Valentina A. Rossi, MD; John R. Stradling, MD; Malcolm Kohler, MD
Author and Funding Information

Conflict of interest statement: None of the authors declare conflicts of interest associated with this manuscript.

Author contributions

Conception and design: EIS, MK, JRS. Data acquisition: EIS, CS, VAR. Analysis and interpretation of data: EIS, MK, JRS. Drafting the article: EIS, MK. Revising the article for important intellectual content and final approval: All authors.

Competing interests

None of the authors has a competing interest regarding this manuscript.

Funding

This work was supported by Swiss National Science Foundation grants (32003B_124915 and 143365) and the Clinical Research Priority Program (CRPP) Sleep and Health of the University of Zurich. The sponsors had no role in design and conduct of the studies, collection, analysis and interpretation of the data, nor in preparation of the manuscript.

Clinical trial registration:ClinicalTrials.gov ( NCT01332175 & NCT01797653) and Controlled-Trials.com (ISRCTN 93153804).

1Sleep Disorders Center and Pulmonary Division, University Hospital of Zurich, Zurich, Switzerland

2National Institute for Health Research (NIHR) Oxford Biomedical Research Centre based at Oxford University Hospitals NHS Foundation Trust and University of Oxford

3Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland

Corresponding author address Prof Malcolm Kohler Chair Respiratory Medicine, Clinical Director Division of Pulmonology and Sleep Disorders Centre University Hospital of Zurich Raemistrasse 100, Zurich, Switzerland


Copyright 2016, . All Rights Reserved.


Chest. 2016. doi:10.1016/j.chest.2016.07.012
Text Size: A A A
Published online

Abstract

Background  Based on meta-analyses, the blood pressure (BP) lowering effect of continuous positive airway pressure (CPAP) therapy in patients with obstructive sleep apnea (OSA) is reported to be approximately 2-3mmHg. This figure is derived from heterogeneous trials, often limited by poor CPAP-adherence, and thus possibly underestimating the treatment effect. We analyzed morning BP data from three randomized controlled CPAP withdrawal trials which included only patients with optimal CPAP-compliance.

Methods  Within the three trials, 149 OSA patients on CPAP were randomized to continue therapeutic CPAP (n=65) or to withdraw CPAP (n=84) for two weeks. Morning BP was measured at home before, and after sleep studies in hospital.

Results  CPAP-withdrawal was associated with a return of OSA (apnea-hypopnea index (AHI) at baseline 2.8/h, at follow-up 33.2/h). Systolic office BP increased in the CPAP-withdrawal group, compared to CPAP-continuation, by +5.4mmHg (95%CI 1.8-8.9mmHg, p=0.003), and systolic home BP by +9.0mmHg (95%-CI 5.7-12.3mmHg, p<0.001). Diastolic office BP increased by +5.0mmHg (95%CI 2.7-7.3mmHg, p<0.001), and diastolic home BP by +7.8mmHg (95%CI 5.6-10.4mmHg, p<0.001).AHI, baseline home systolic BP, statin usage, gender, and number of antihypertensive drugs were all independently associated with systolic BP change in multivariate analysis, controlling for age, BMI, smoking, diabetes, and sleepiness.

Conclusions  CPAP-withdrawal results in a clinically relevant increase in BP, which is considerably higher than in conventional CPAP trials, and is also underestimated when office BP is used. Greater OSA severity is associated with a higher BP rise in response to CPAP-withdrawal.


Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Figures

Tables

References

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
Guidelines
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543