U-Shaped Association Between Monocyte-Lymphocyte Ratio and Risk of Cardiac Conduction Block

Abstract

Man Li,1,2,* Xintao Li,3,* Hongwei Gao,4 Peng Li,1 Li Zhang,1 Xiaoling Zhang,1 Peipei Liu,5 Xuemei Yang,2 Lili Wu,6 Jiangwei Zeng,2 Shouling Wu,7 Lixia Sun1 1Department of Emergency, The Affiliated Hospital of North China University of Science and Technology, Tangshan, People’s Republic of China; 2Graduate School, North China University of Science and Technology, Tangshan, People’s Republic of China; 3Department of Cardiology, The First Hospital of Soochow University, Jiangsu, People’s Republic of China; 4Department of Emergency, Caofeidian District hospital of Tangshan City, Tangshan, People’s Republic of China; 5School of Public Health, North China University of Science and Technology, Tangshan, People’s Republic of China; 6Department of Cardiology, Shanghai Songjiang District Central Hospital, Shanghai, People’s Republic of China; 7Department of Cardiology, Kailuan Hospital, Tangshan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lixia Sun, Department of Emergency, The Affiliated Hospital of North China University of Science and Technology, Tangshan, 063000, People’s Republic of China, Email [email protected] Shouling Wu, Department of Cardiology, Kailuan General Hospital, Tangshan, 063000, People’s Republic of China, Email [email protected]: Inflammation plays a critical role in the development of cardiac conduction block (CCB), which is associated with an increased risk of morbidity and mortality. The monocyte-lymphocyte ratio (MLR) acts as a novel inflammatory marker; however, its association with CCB has not yet been studied. This study aimed to investigate the association between MLR and CCB risk.Patients and Methods: In total, 82,472 CCB-free participants were identified from the Kailuan study. MLR was calculated using the monocyte count/lymphocyte count. The participants were stratified based on quartiles of MLR levels. Incident CCB and its subtypes were ascertained from electrocardiograms at biennial follow-up visits. The Cox proportional hazards model and restricted cubic spline analysis were used to investigate the association between MLR with CCB and its subtypes.Results: During a median follow-up of 10.4 years, 3222 incident CCB cases were observed. A U-shaped association was observed between MLR and CCB risk (Pnonlinearity < 0.05). After multivariate adjustment, individuals in the highest MLR quartile had a hazard ratio (HR) of 1.212 (95% CI: 1.097-1.340; Q4 vs Q2), while those in the lowest MLR quartile had an HR of 1.106 (95% CI: 1.000-1.224; Q1 vs Q2). Sensitivity and subgroup analyses yielded consistent results. The U-shaped association persisted for atrioventricular block (AVB) in subtype analyses.Conclusion: MLR was significantly associated with an increased risk of new-onset CCB. Assessing MLR may have clinical relevance for predicting CCB risk, providing valuable insights for preventive strategies and patient management.Pre-Registered Clinical Trial Number: The pre-registered clinical trial number is ChiCTR-TNC-11001489. Keywords: cardiac arrhythmia, cardiac conduction block, inflammation, monocyte-lymphocyte ratio, risk factors

Keywords

• cardiac arrhythmia
• cardiac conduction block
• inflammation
• monocyte-lymphocyte ratio
• risk factors