Association of white blood cell count and clustered components of metabolic syndrome in Japanese men

Background: The role of inflammation in the genesis of cardiovascular disease has attracted attention and in the present study the association among metabolic syndrome (MS), white blood cell (WBC) count, and insulin concentration was investigated. Methods and Results: A cross-sectional study of 3,594 Japanese men aged 34-69 years evaluated the MS components (high blood pressure, hypo-high density lipoprotein (HDL)-cholesterolemia, hypertriglyceridemia, hyperglycemia), as defined by the criteria given in the Third Report of the National Cholesterol Education Program Expert Panel on Detection Evaluation, and Treatment of High Blood Cholesterol in Adults, except for obesity [body mass index (BMI) ≥25 kg/m²]. WBC count had a positive correlation with BMI, blood pressure, triglyceride, glucose and insulin, and a negative correlation with HDL-cholesterol. The multi-adjusted means of WBC count and insulin concentration were significantly higher in MS subjects defined as having 3 or more of the components than in non-MS subjects with no more than 2 components. Both means also increased with the number of MS components (p<0.001 for trend). In the multiple linear regression analysis, BMI, HDL-cholesterol, systolic blood pressure, glucose and triglyceride had a significant and independent association with WBC count, but the insulin concentration did not. Conclusions: The cluster of MS components based on insulin resistance may cause low-grade inflammation.