High serum β2-microglobulin levels are associated with poor functional outcomes in patients with acute ischemic stroke

Abstract

Abstract Background Elevated serum levels of β2-microglobulin (β2M) are a risk factor for adverse cardiovascular events and neurocognitive decline. This study aimed to evaluate the association between serum β2M levels and prognosis in patients with acute ischemic stroke (AIS) and to determine whether the association was affected by any clinical variables. Methods All participants who were recruited for our study (n = 533) were inpatients at our hospital. After applying the study’s inclusion and exclusion criteria, 441 eligible patients were included. Using multiple regression modeling, the association between serum levels of β2M and poor functional outcomes—which were classified as being modified Rankin Scale (mRS) scores of 3–6 (composite score of death and major disability), 3–5 (major disability), and 6 (death)—were assessed 3 months after stroke onset. Results At the 3-month follow-up assessment, 209 (47.39%) participants had poor functional outcomes, including 150 (34.01%) cases of major disabilities and 59 (13.38%) deaths. After adjusting for important covariates, the highest proportion of individuals with modified Rankin Scale scores of 3–6 (odds ratio [OR], 3.54; 95% confidence interval [CI], 1.35–9.33), 3–5 (OR, 2.95; 95% CI, 1.21–7.16), or 6 (OR, 1.02; 95% CI, 0.29–3.64) exhibited serum levels of β2M in the highest quartile compared with individuals with levels in the lowest quartiles. By incorporating β2M levels into models that included conventional risk factors, risk prediction for the combined outcome of death and major disability was improved. After subgroup analysis, a significant association was observed only in patients with AIS whose time from onset to hospitalization was < 12 hours (P for interaction < 0.05). Conclusions Elevated serum levels of β2M were associated with poor functional outcomes in patients with AIS. This association was affected by the time from onset to hospitalization. Trial registration: This study protocol was registered at clinicaltrials.gov (registration number, ChiCTR2100045815 and registration date, April 25, 2021).