β2-microglobulin is an independent indicator of acute kidney injury and outcomes in patients with intracerebral hemorrhage

Acute kidney injury (AKI), a serious complication in critically ill patients, is associated with poor clinical outcomes. We explored the hypothesis that beta2-microglobulin (beta2-MG) is an independent indicator of AKI development and outcomes in patients with intracerebral hemorrhage (ICH) in the neurosurgical intensive care unit (NICU).Patients with ICH (n = 403) admitted to the NICU of Zhongnan Hospital, Wuhan University, between January 1, 2015 and December 31, 2016 were prospectively enrolled in this single-center, observational study. The primary outcome was the incidence of AKI, secondary outcomes were in-hospital mortality and 1-year mortality (from time of admission).The overall AKI incidence, in hospital, was 35.2%; patients were diagnosed with stage 1 (22.1%), 2 (5.7%), and 3 (7.4%) AKI. beta2-MG levels predicted AKI with an area under the curve of 0.712 (95% confidence interval [CI], 0.652-0.772) and a cut-off of 2026.85 mug/L (sensitivity, 57.5%; specificity, 79.4%). Compared with the group having lower beta2-MG values, the group with higher values (beta2-MG >2123.50 mug/L) had significantly higher risks of AKI (odds ratio, 2.606; 95% CI, 1.315-5.166), in-hospital mortality (hazard ratio [HR], 2.548; 95% CI, 1.318-4.924), and 1-year mortality (HR, 3.161; 95% CI, 1.781-5.611) in adjusted analyses.beta2-MG levels predict AKI development and outcomes in patients with ICH in the NICU.