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The coagulation and protein C pathways in patients with sleep apnea

Takehiro Takagi1, John Morser, Esteban C Gabazza

  • 1Department of Pulmonary and Critical Care Medicine, Mie University Graduate School of Medicine, Tsu-city, Mie, Japan.

Lung
|June 10, 2009
PubMed

Insights

Obstructive sleep apnea (OSA) patients show increased clotting, but the protein C anticoagulant pathway is not implicated. This study suggests other mechanisms are responsible for hypercoagulability in OSA.

Area of Science:

  • Cardiovascular Medicine
  • Sleep Medicine
  • Hematology

Background:

  • Obstructive sleep apnea (OSA) is linked to increased cardiovascular disease risk.
  • Hypercoagulability is a suspected mechanism contributing to vascular events in OSA patients.
  • The role of the protein C anticoagulant pathway in OSA-related hypercoagulability remains unclear.

Purpose of the Study:

  • To investigate potential dysfunction in the protein C anticoagulant pathway in patients diagnosed with obstructive sleep apnea.
  • To determine if the protein C pathway contributes to the hypercoagulable state observed in OSA.

Main Methods:

  • Enrolled 293 patients for the study.
  • Utilized all-night polysomnography, including SpO2 monitoring, for OSA diagnosis.
  • Assessed plasma levels of thrombin-antithrombin complex, activated protein C/alpha-antitrypsin complex, and soluble thrombomodulin.

Main Results:

  • Patients with an apnea-hypopnea index (AHI) > 5 exhibited higher plasma thrombin-antithrombin complex levels compared to those with AHI < 5.
  • No significant differences were observed in activated protein C/alpha-antitrypsin complex or soluble thrombomodulin levels between OSA and non-OSA groups.
  • These findings indicate that the protein C anticoagulant pathway is not significantly affected in OSA patients.

Conclusions:

  • The protein C anticoagulant pathway does not appear to be impaired in patients with obstructive sleep apnea.
  • The study suggests that the protein C pathway is likely not involved in the hypercoagulability associated with sleep-disordered breathing.

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