Effects of obstructive sleep apnoea and its treatment on cardiovascular risk in cad patients. (12th October 2011)

• Record Type: Journal Article
• Authors: Qing, Zhao; Zhihong, Liu; Zhihui, Zhao; Qin, Luo; Doug, Mcevoy; Hongliang, Zhang; Yong, Wang
• Is Part Of: Heart. Volume 97(2011)Supplement 3
• Page Start: A136
• Page End: A136
• Publication Date: 2011-10-12
• Subjects: Heart -- Diseases -- Treatment -- Periodicals; Cardiology -- Periodicals; 616.12
• DOI: 10.1136/heartjnl-2011-300867.395
• Languages: English
• ISSNs: 1355-6037

Abstract

Abstract : Objective: 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. Methods: One hundred and fifty one Chinese patients with proven CAD and standard medication were enrolled. After polysomnography, patients were classified into four groups according to apnoea-hypopnoea 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. Results: 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. Conclusions: 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.