The predictive value of microRNA‐21 for sepsis risk and its correlation with disease severity, systemic inflammation, and 28‐day mortality in sepsis patients

Background This study aimed to investigate the value of microRNA (miR)‐21 for predicting sepsis risk and its correlation with inflammation, disease severity as well as 28‐day mortality in sepsis patients. Methods Totally, 219 sepsis patients and 219 healthy controls (HCs) were recruited. Plasma samples were obtained from sepsis patients within 24 hours after admission and from HCs at the enrollment to detect miR‐21 expressions by real‐time quantitative polymerase chain reaction. Besides, the clinical characteristics of sepsis patients were recorded and the 28‐day mortality of sepsis patients was evaluated. Results MiR‐21 expression was decreased in sepsis patients compared with HCs, and further receiver operating characteristic (ROC) curve analysis revealed that miR‐21 was of a good value in predicting sepsis risk (area under the curve [AUC]: 0.801, 95% CI: 0.758‐0.844). Besides, miR‐21 expression was negatively associated with acute pathologic and chronic health evaluation II (APACHE II) and sequential organ failure assessment (SOFA) score in sepsis patients. Furthermore, miR‐21 expression was negatively correlated with serum creatinine, C‐reactive protein, tumor necrosis factor‐α, interleukin (IL)‐1β, IL‐6, and IL‐17, while positively correlated with albumin in sepsis patients. However, there was no correlation of miR‐21 expression with white blood cell, smoke, or comorbidities in sepsis patients. Additionally, ROC curve analysis displayed that miR‐21 exhibited a poor predictive value for 28‐day mortality risk in sepsis patients (AUC: 0.588, 95% CI: 0.505‐0.672). Conclusion MiR‐21 might serve as a potential biomarker for the development and progression of sepsis, while not for prognosis prediction in sepsis patients.