Abstract
Background
Obstructive sleep apnea (OSA) is closely related to the incidence and progression of coronary artery disease (CAD), but the mechanisms linking OSA and CAD are unclear. C1q/TNF-related protein-9 (CTRP9) is a novel adipokine that protects the heart against ischemic injury and ameliorates cardiac remodeling.
Purpose
We aimed to ascertain the clinical relevance of CTRP9 with OSA prevalence in patients with CAD.
Methods
From August 2016 to March 2019, consecutive eligible patients with CAD (n=154; angina pectoris, n=88; acute myocardial infarction [AMI], n=66) underwent cardiorespiratory polygraphy during hospitalization. OSA was defined as an apnea-hypopnea index (AHI) ≥15 events h–1. Plasma CTRP9 concentrations were measured by ELISA method.
Results
OSA was present in 89 patients (57.8%). CTRP9 levels were significantly decreased in the OSA group than in the non-OSA group (4.7 [4.1–5.2] ng/mL vs. 4.9 [4.4–6.0] ng/mL, P=0.003). The difference between groups was only observed in patients with AMI (3.0 [2.3–4.9] vs. 4.5 [3.2–7.9], P=0.009), but not in patients with AP (5.0 [4.7–5.3] ng/mL vs. 5.1 [4.7–5.9] ng/mL, P=0.571) (Figure 1). Correlation analysis showed that CTRP9 levels were negatively correlated with AHI (r=−0.238, P=0.003) and oxygen desaturation index (r=−0.234, P=0.004), and positively correlated with left ventricular ejection fraction (r=0.251, P=0.004) in all subjects. Multivariate analysis showed that male gender (OR 3.099, 95% CI 1.029–9.330, P=0.044), body mass index (OR 1.148, 95% CI 1.040–1.268, P=0.006), and CTRP9 levels (OR 0.726, 95% CI 0.592–0.890, P=0.002) were independently associated with the prevalence of OSA.
Conclusions
Plasma CTRP9 levels were independently related to the prevalence of OSA in patients with CAD, suggesting that CTRP9 might play a role in the pathogenesis of CAD exacerbated by OSA.
Figure 1. CTRP9 levels in OSA and non-OAS groups
Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China