Objective To investigate the significance of plasma levels of insulin-like growth factor(IGF)-1 and insulin-like growth factor binding protein(IGFBP)-3 in predicting acute respiratory distress syndrome(ARDS)and prognosis in critical patients.Methods A totally of 131 critical patients in intensive care unit(ICU)of the First Affiliated Hospital of Wenzhou Medical University were reviewed.Plasma concentrations of IGF-1,IGFBP-3,blood biochemistry,procalcitonin(PCT),lactic acid(LAC)and blood albumin were measured in enrolled patients.The 60-day fatality of enrolled patients was calculated.The differences between ARDS group and control group,as well as 60-day dead group and survival group were compared.Results Plasma IGF-1 and IGFBP-3 in ARDS group were significantly lower than those in control group,while plasma PCT was higher than that in control group.Plasma levels of IGF-1 and IGFBP-3 in dead group were significantly lower than those in survival group.Multivariate Logistic regression analysis and receiver operating characteristic curve results showed that IGF-1 area under curve(AUC)was 0.770,sequential organ failure assessment(SOFA)(AUC=0.692)and PCT(AUC=0.710)were independent risk factors for ARDS in critical patients.IGF-1(AUC=0.807),IGFBP-3(AUC=0.759)and SOFA score(AUC=0.859)were independent risk factors for death in critical patients.Conclusion The plasma levels of IGF-1 and IGFBP-3 in critica patients are significantly decreased,which may be an important factor for ARDS risk and fatality in critical patients.