Effect of Monocyte-to-Lymphocyte Ratio on Heart Failure Characteristics and Hospitalizations in a Coronary Angiography Cohort

Inflammation is a shared mechanism in coronary artery disease (CAD) and subsequent heart failure (HF), and circulating monocyte and lymphocyte counts predict CAD severity and outcomes. We investigated whether the monocyte-to-lymphocyte ratio (MLR) correlates with biomarkers of HF and extent of CAD, as well as future HF hospitalizations in patients undergoing coronary angiography. Therefore, we studied 1754 patients undergoing coronary angiography for stable CAD, unstable angina, or myocardial infarction. MLR was determined at blood draw before angiography and related cross-sectionally to HF biomarkers (ejection fraction, N-terminal pro-B-type natriuretic peptide [NTproBNP] levels) and CAD severity, as well as longitudinally with risk of HF hospitalizations during follow-up. In the entire cohort, median (interquartile range) MLR was 0.32 (0.24 to 0.43). High MLR was defined as the upper quartile and significantly associated with nonstable CAD (unstable angina; odds ratio [OR] 1.13, 95% confidence interval 1.06 to 1.21] or myocardial infarction [OR 1.10, 1.04 to 1.16]), more severe CAD (OR 1.39, 1.15 to 1.68), poorer ejection fraction (OR 1.63, 1.29 to 2.05), and higher NTproBNP levels (β 0.78, 0.59 to 0.96), all p <0.001. The associations with nonstable CAD and NTproBNP remained highly significant after covariate adjustment. Over a mean follow-up of 1.3 years, 46 HF hospitalizations occurred. A high MLR was significantly and independently predictive of HF hospitalizations during follow-up (hazard ratio 2.1 [1.1 to 4.1], p = 0.039) after adjustment for covariates and addition of MLR to the basic model significantly improved reclassification. In conclusion, MLR is strongly related to HF markers and predicts HF hospitalizations during follow-up in patients with CAD.