Association of Novel Hematologic Inflammatory Biomarkers with Cardiovascular Disease in Patients with Obstructive Sleep Apnea

Background: Heightened inflammatory state is considered a key factor linking obstructive sleep apnea (OSA) with cardiovascular disease (CVD). Objective: This study aimed to assess the level of novel hematologic inflammatory biomarkers including neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), ratio of neutrophil count to HDL level (NHR), ratio of monocyte count to HDL level (MHR), monocyte count multiplied by neutrophil-to-lymphocyte ratio (SIRI) in OSA patients, and explored the relationships between these inflammatory biomarkers and cardiovascular risk. Methods: This study enrolled 974 patients with OSA and all data were collected after admission. Spearman correlation was used to explore the correlations between sleep parameters and inflammatory indices. Logistic regression and receiver operating characteristic (ROC) analysis were employed to assess the association between the novel hematologic inflammatory indices and CVD in OSA patients. Results: Correlation analysis showed that most inflammatory indices were closely related to nocturnal hypoxia in OSA patients. Multivariate logistic regression suggested that NLR (OR=1.085, 95% CI: 1.017-1.158), MLR (OR=3.708, 95% CI: 1.322-10.404), NHR (OR=1.074, 95% CI: 1.020-1.131), MHR (OR=2.116, 95% CI: 1.205-3.715), and SIRI (OR=1.148, 95% CI: 1.035-1.272) were positively correlated with CVD in OSA patients after adjusting all confounding factors. Moreover, the area under the curve (AUC) of NLR, MLR, NHR, MHR, and SIRI for discriminating OSA patients with CVD was 0.734, 0.735, 0.736, 0.734, and 0.735, respectively, after adjusting for all confounders. Conclusion: Inflammatory indices including NLR, MLR, NHR, MHR, and SIRI were promising biomarkers for CVD in OSA patients, which might aid in the early identification of CVD risk in clinical. These easily obtainable markers may facilitate CVD risk stratification in OSA patients.