Meta-analysis of differences in neutrophil to lymphocyte ratio between hypertensive and non-hypertensive individuals

This study systematically reviewed the evidence regarding differences in the neutrophil to lymphocyte ratio (NLR) level between hypertensive and normotensive individuals as well as between patients with dipper and non-dipper hypertension (HTN). PubMed, Scopus, and Web of Science databases were systematically searched up to 20 December 2021. This was done without any limitation with regard to date, publication, or language. Pooled weighted mean differences (WMD) with 95% confidence intervals (95% CI) were reported. We assessed the quality of studies based on the Newcastle–Ottawa Scale (NOS). In total, 21 studies were included in our study. There was a significant increase in NLR levels for the hypertensive group in comparison to the control group (WMD = 0.40, 95%CI = 0.22–0.57, P < 0.0001). In addition, the NLR levels were higher in the non-dipper than in the dipper group (WMD = 0.58, 95%CI = 0.19–0.97, P = 0.003). Our findings showed that hypertensive patients had higher level of NLR than normotensive individuals.