Blood Neutrophil to Lymphocyte Ratio as a Predictor of Hypertension

Abstract

BACKGROUND: Hypertension is a significant global public health challenge. Low-grade inflammation is known to facilitate the development of essential hypertension and target-organ hypertensive damage. Neutrophil to lymphocyte ratio (NLR) is a simple and reliable indicator of inflammation that may also be useful in the prediction of hypertension. METHODS: Participants were recruited from Tianjin Medical University's General Hospital-Health Management Centre. A total of 28,850 initially hypertension-free subjects were followed from 2007 to 2013. Adjusted Cox proportional hazards regression models were used to assess relationships between NLR categories and incidence of hypertension. RESULTS: During the ~6-year follow-up period (median duration of follow-up (interquartile range): 2.63 (2.58-2.68)), 1,824 subjects developed hypertension. The hazard ratios of hypertension incidence were evaluated in increasing NLR quintiles. Compared with participants with the lowest NLR levels, the multivariable-adjusted hazard ratios (95% confidence interval) of hypertension were related to increasing NLR quintiles and were as follows: 1.08 (0.92, 1.26), 0.97 (0.83, 1.14), 1.10 (0.94, 1.28), and 1.23 (1.06, 1.43), respectively (P for trend < 0.01). Similar results also were observed in the white blood cell and neutrophil counts, but not lymphocyte counts. CONCLUSIONS: The study is the first to show the elevated NLR levels significantly correlate with an increased risk of developing hypertension. This result may be useful in elucidating the mechanism underlying the development of hypertension. New therapeutic approaches aimed at inflammation might be proposed to control hypertension and hypertensive damage.