Monocyte count as a predictor of cardiovascular mortality in older Korean people

Abstract

Background: white blood cells (WBCs) have been known to mediate the inflammatory process, which may be a pivotal mechanism for atherosclerosis and cardiovascular mortality. Objective: we investigated which WBC subtypes increased cardiovascular mortality and explored its connection to coronary artery diseases in a prospective study among older Koreans. Study design and subjects: this study was conducted from 2005 to 2011 as a part of the Korean Longitudinal Study on Health and Aging and included 439 men and 561 women over 65-year old. Outcomes: the primary endpoints were all-cause and cardiovascular mortality. Results: in the cox proportional hazard models, subjects in the higher tertiles of monocyte count were at a higher risk for cardiovascular mortality even in the fully adjusted model (2nd tertile hazard ratio = 2.51; 3rd tertile = 2.81). However, the total WBC, neutrophil and lymphocyte counts did not affect cardiovascular mortality. Logistic regression models revealed that subjects in the 3rd tertile of monocyte count had an increased risk for any coronary artery plaque, vulnerable plaque and calcified plaque (odds ratio = 1.80, 2.68, 1.59, respectively) but not for significant stenosis. Other WBC subtypes were not related to coronary artery diseases. Conclusion: the results showed that a high monocyte count is a risk factor for cardiovascular mortality as well as coronary artery plaque formation.