0
Original Research: SLEEP MEDICINE |

Daytime Hypercapnia in Obstructive Sleep Apnea Syndrome*

Naoko Kawata, MD; Koichiro Tatsumi, MD, FCCP; Jiro Terada, MD; Yuji Tada, MD; Nobuhiro Tanabe, MD, FCCP; Yuichi Takiguchi, MD, FCCP; Takayuki Kuriyama, MD, FCCP
Author and Funding Information

*From the Department of Respirology, Graduate School of Medicine, Chiba University, Chiba, Japan.

Correspondence to: Koichiro Tatsumi, MD, Department of Respirology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuou-ku, Chiba 260-8670, Japan; e-mail: tatsumi@faculty.chiba-u.jp



Chest. 2007;132(6):1832-1838. doi:10.1378/chest.07-0673
Text Size: A A A
Published online

Background: The pathogenesis of daytime hypercapnia (Paco2 ≥ 45 mm Hg) may be directly linked to the existence of obstructive sleep apnea syndrome (OSAS) per se, although only some patients with OSAS exhibit daytime hypercapnia.

Objective: To investigate the prevalence of daytime hypercapnia in patients with OSAS; the association of daytime hypercapnia and obesity, obstructive airflow limitation, restrictive lung impairment, and severity of sleep apnea; and the response to continuous positive airway pressure (CPAP) therapy in a subset of subjects.

Methods: The study involved 1,227 patients with OSAS who visited a sleep clinic and were examined using polysomnography. As for the response to CPAP therapy, the patients were considered good responders if their daytime Paco2 decreased ≥ 5 mm Hg and poor responders if it decreased < 5 mm Hg.

Results: Fourteen percent (168 of 1,227 patients) exhibited daytime hypercapnia. These patients had significantly higher body mass index (BMI) and apnea-hypopnea index (AHI) values compared with normocapnic patients, while percentage of predicted vital capacity (%VC) and FEV1/FVC ratio did not differ between the two groups. Logistic regression analysis showed that only AHI was a predictor of daytime hypercapnia (p < 0.0001), while BMI (p = 0.051) and %VC (p = 0.062) were borderline predictors of daytime hypercapnia. Daytime hypercapnia was corrected in some patients (51%, 19 of 37 patients) with severe OSAS after 3 months of CPAP therapy.

Conclusion: The pathogenesis of daytime hypercapnia may be directly linked to sleep apnea in a subgroup of patients with OSAS.

Figures in this Article

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.

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