Original Contribution White Blood Cell Count and Risk for All-Cause, Cardiovascular, and Cancer Mortality in a Cohort of Koreans

The authors conducted a 10-year prospective cohort study of mortality in relation to white blood cell counts of 437,454 Koreans, aged 40–95 years, who received health insurance from the National Health Insurance Corpora-tion andweremedically evaluated in 1993or 1995, withwhite blood cell measurement. Themain outcomemeasures were mortality from all causes, all cancers, and all atherosclerotic cardiovascular diseases (ASCVD). Hazard ratios and 95 % confidence intervals were calculated using Cox proportional hazards models with adjustment for age and potential confounders. During follow-up, 48,757 deaths occurred, with 15,507 deaths from cancer and 11,676 from ASCVD. For men and women, white blood cell count was associated with all-cause mortality and ASCVD mortality but not with cancer mortality. In healthy nonsmokers, a graded association between a higher white blood cell count and a higher risk of ASCVD was observed in men (highest vs. lowest quintile: hazard ratio 2.10, 95 % confidence interval: 1.50, 2.94) and in women (hazard ratio 1.35, 95 % confidence interval: 1.17, 1.56). In healthy smokers, a graded association between a higher white blood cell count and a higher risk of ASCVDwas also observed in men (highest vs. lowest quintile: hazard ratio 1.46, 95%confidence interval: 1.25, 1.72). These findings indicate that the white blood cell count is an independent risk factor for all-cause mortality and for ASCVD mortality. arteriosclerosis; cardiovascular diseases; death; leukocytes; neoplasms Abbreviation: ASCVD, atherosclerotic cardiovascular diseases