The predictive role of the neutrophil–lymphocyte ratio in the prognosis of adult patients with stroke

Our study aimed to determine the effect of the neutrophil–lymphocyte ratio on the prognosis of adult patients with acute stroke. We searched the Web of Science, PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure databases and selected all of the potentially eligible studies. From the included studies, we extracted characteristics such as the stroke type and acquisition time until routine blood collection and the odds ratios across studies. The 95% confidence intervals and odds ratios were pooled to calculate the effect size for the neutrophil–lymphocyte ratio in acute stroke patients. We defined poor function outcomes according to the modified Rankin Scale ≥ 3 or Glasgow Outcome Scale< 3.Thirteen studies with 4443 patients were included in our analysis, including 7 ischemic and 6 hemorrhagic stroke studies. The pooled odds ratios for poor functional outcome at 3 months with a higher neutrophil–lymphocyte ratio in acute ischemic and hemorrhagic patients were 1.689 (95% CI = 1.184–2.409, p < 0.001) and 1.125 (95% CI = 1.022–1.239, p < 0.001), respectively, and the overall pooled odds ratio for poor functional outcome following stroke was 1.257 (95% CI = 1.146–1.379, p < 0.001). At the same time, the overall combined odds ratio for death at 3 months was 1.632 (95% CI = 1.155–2.306, p < 0.001).The neutrophil–lymphocyte ratio, an easily calculated marker, plays a predictive role in the short-term outcomes of adult patients (mean age ≥ 50 years) following acute ischemic and hemorrhagic stroke.