title: Effects of obstructive sleep apnea and its treatment on cardiovascular risk in CAD patients.
abstract: This study, in optimally treated CAD patients with newly diagnosed OSA, focused on (1) The relationships between OSA and serum biomarkers of four potential pathways of cardiovascular injury in OSA: high-sensitivity C-reactive protein (hs-CRP), endothelin-1 (ET-1), N terminal pro B type natriuretic peptide (NT-proBNP) and fibrinogen; and (2) The effect of continuous positive airway pressure (CPAP) therapy on these markers. 151 Chinese patients with proven CAD and standard medication were enrolled. After polysomnography, patients were classified into four groups according to apnea-hypopnea index (AHI): no OSA (n = 25); mild OSA (n = 50); moderate OSA (n = 43); severe OSA (n = 33). Morning levels of hs-CRP, ET-1, NT-proBNP and fibrinogen were assayed and repeated in severe OSA patients after 3-months CPAP treatment. Hs-CRP was greater in patients with severe OSA than those with no OSA or mild OSA (P = 0.001, P = 0.003; respectively). After adjustment for confounders, the hs-CRP levels correlated most strongly with AHI and oxygen desturation index (ODI) (r = 0.439, P < 0.001; r = 0.445, P < 0.001; respectively). In stepwise multiple linear regressions, the strongest predictor of hs-CRP levels was ODI (P < 0.001). After 3 months of CPAP treatment, the hs-CRP levels deceased (P = 0.005) in CAD patients with severe OSA. In CAD patients on current optimal medications, hs-CRP is significantly correlated with the severity of OSA, and the elevated hs-CRP levels can be decreased by CPAP. This suggests that OSA could activate vascular inflammation in CAD patients despite current best practice medications.
authors.affiliation: Center for Pulmonary Vascular Disease Diagnosis and Treatment, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Beilishi Road, Xicheng District, Beijing, P.R. China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhao
authors.forename: Zhi-hong
authors.initials: ZH
authors.lastname: Liu
authors.forename: Zhi-hui
authors.initials: ZH
authors.lastname: Zhao
authors.forename: Qin
authors.initials: Q
authors.lastname: Luo
authors.forename: R Doug
authors.initials: RD
authors.lastname: McEvoy
authors.forename: Hong-liang
authors.initials: HL
authors.lastname: Zhang
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000378:metabolism* / Q000503:physiopathology; D045422:Continuous Positive Airway Pressure / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D019332:Endothelin-1 / Q000378:metabolism; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology / Q000628:therapy*
chemical_list: D015415:Biomarkers; D019332:Endothelin-1; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D005340:Fibrinogen; D002097:C-Reactive Protein