High neutrophil to lymphocyte ratio is associated with white matter hyperintensity in a healthy population

High neutrophil to lymphocyte ratio (NLR) is correlated with the occurrence, morbidity and mortality of cerebrovascular disease as a marker of systemic inflammation. However, its effect on cerebral white matter hyperintensity (WMH) is unclear. We investigated high NLR burden as a surrogate marker of WMH volume in a healthy population. Healthy subjects with voluntary health check-ups between January 2006 and December 2013, including brain MRI and laboratory examination, were collected. WMH volumes were rated quantitatively. A total of 2875 subjects were enrolled, and the mean volume of WMH was 2.63±6.26mL. In multivariate linear regression analysis, NLR [β=0.191, 95% confidence interval (CI)=0.104 to 0.279, P<0.001] remained significant after adjusting for confounders. Age (β=0.049, 95% CI=0.045 to 0.054, P<0.001), hypertension (β=0.191, 95% CI=0.101 to 0.281, P<0.001), diabetes (β=0.153, 95% CI=0.045 to 0.261, P=0.006), and extracranial atherosclerosis (β=0.348, 95% CI=0.007 to 0.688, P=0.045) were also significant independently from NLR. Additionally, the high NLR group (NLR≥1.52) was related to male sex, hypertension, diabetes, current smoking, extracranial atherosclerosis, silent brain infarct, and high WMH volumes. In conclusion, high NLR is associated with larger WMH volumes in a healthy population. Assessment of NLR may be helpful in detecting cerebral WMH burdens in high risk groups.