Objective:To investigate associations of serum β 2-microglobulin (β 2M) with baseline stroke severity and outcome at 3 months after onset in patients with acute ischemic stroke (AIS). Methods:Patients with first-ever AIS admitted to the Department of Neurology, the Affiliated Municipal Hospital of Xuzhou Medical University from January 2018 to May 2022 were included retrospectively. The severity of stroke was evaluated according to the National Institute of Health Stroke Scale score at admission. ≤8 was defined as mild stroke, and >8 was defined as moderate to severe stroke. At 3 months after onset, the modified Rankin Scale was used to evaluate the clinical outcome, ≤2 points was defined as good outcome and >2 points was defined as poor outcome. Multivariate logistic regression analysis was used to determine associations of β 2M with the severity and outcome of stroke. Results:A total of 463 patients with AIS were enrolled, including 263 males (56.68%), aged 62.89±11.77 years. There were 319 patients (68.89%) in the mild stroke group and 144 (31.10%) in the moderate to severe stroke group; 304 patients (65.66%) in the good outcome group and 159 (34.34%) in the poor outcome group. Univariate analysis showed that the β 2M in the moderate to severe stroke group and the poor outcome group were significantly higher than those in the mild stroke group and the good outcome group, respectively (all P<0.05). Multivariate logistic regression analysis showed that β 2M was an independent influencing factor for stroke severity (odds ratio 2.476, 95% confidence interval 1.621-3.783; P<0.001) and poor outcome (odds ratio 5.179, 95% confidence interval 2.941-11.121; P<0.001) in patients with AIS. Conclusion:There is a significant independent correlation between high serum β 2M and the severity and poor outcome of stroke in patients with AIS.

The nervous system and the immune system maintain homeostasis mainly through the hypothalamo-pituitary-adrenal(HPA)axis,the sympathetic nervous system and the parasympathetic nervous system(vagal cholinergic pahway).The homeostasis is broken after stroke,and results in peripheral immunosuppression,which is called stroke-induced immunodepression syndrome.Its mechanism is still under investigation.The article reviews the mechanism and clinical significance of stroke-induced peripheral immunodepression through the above three mentioned pathways.