Incidence, Risk factors, and Biomarkers Predicting Ischemic or Hemorrhagic Stroke Associated Acute Kidney Injury and Outcome: A Retrospective Study in a General Intensive Care Unit

Abstract

Objective: We investigated the epidemiology, risk factors, and predictive parameters for ischemic or hemorrhagic stroke-associated acute kidney injury (AKI) and mortality in a general intensive care unit (ICU) in China. Methods: During 5 years, 479 stroke patients were screened, and 381 were enrolled. AKI was diagnosed within 7 days after ICU admission, based on the Kidney Disease Improving Global Outcomes criteria. Risk factors of AKI were assessed by Logistic regression analyses, and the predictive biomarkers for AKI were determined using receiver operating characteristic (ROC) curves. Also examined were factors influencing 28-day mortality, using Cox regression analyses and Kaplan-Meier curves. ­Results: Among all, 115 (30.18%) patients developed AKI. Multivariate regression analyses revealed that the following features at ICU admission significantly increased the risk of developing AKI: an increased National Institutes of Health Stroke Scale score (OR 1.136, p < 0.001) and Acute Physiology and Chronic Health Evaluation II score (OR 1.107, p = 0.042); hypertension (OR 2.346, p = 0.008); use of loop diuretics (OR 1.961, p = 0.032); and higher serum cystatin C (sCysC; OR 8.156, p = 0.001). The area under the ROC curves for predicting AKI using sCysC was 0.772, slightly better than that of other biomarkers. The sCysC ≥0.93 mg/L (hazard ratio 1.844, p = 0.004) significantly predicted 28-day mortality. Conclusions: Among stroke patients in ICU, we identified significant risk factors of stroke-associated AKI. Serum CysC level at ICU admission was an important biomarker for predicting AKI and 28-day mortality.