Changes and clinical significance of copeptin in patients with traumatic brain injury

doi:10.3969/j.issn.1002-1949.2014.11.007

Abstract：Objective To study the level of plasma copeptin and its clinical significance in the course of traumatic brain injury.Methods A total of 98 patients with traumatic brain injury were enrolled in this study and divided into three groups according to GCS score.The levels of plasma copeptin were measured by ELISA in all subjects.The relationship between the level of plasma copeptin in patients with acute poisoning and GCS score were analyzed.The diagnostic performance of copeptin for prognosis was assessed using ROC analysis.The sensitivity and specificity were inferred based on the positive rate of two clinical index.Results ①The levels of copeptin increased gradually with the degree of traumatic brain injury aggravating, and the difference between three groups have statistical significance.The level of plasma copeptin in three groups with traumatic brain injury was much higher than controls (13.6 ±3.7 ng/mL vs.0.9 ±0.4 ng/mL, P<0.01).②Plasma copeptin was negatively correlated with GCS score(r=-0.79, P<0.01),and positively correlated with blood glucose(r=0.68,P<0.01) .③The level of plasma copeptin in vegetative or death group were much higher than that of non-death groups(19.3 ±2.6,9.2 ±1.5 vs.7.1 ±3.9, P<0.05 or 0.01).The GCS score in vegetative or death group and good prognosis group were lower than that in bad prognosis group(5.7 ± 1.4,7.1 ±2.9 vs.9.3 ±2.8,P<0.05), but there were no difference in vegetative or death group and good prognosis groups ( P >0.05).④A receiver operating characteristic curve showed that plasma copeptin concentration predicted month mortality(area under curve=0.803, 95%CI 0.712~0.893). Using 8.5 ng/mL as cut off value, the sensitivity and specificity of copeptin were 84.2%and 67.3%to predict death. Conclusion Serum copeptinis increased in patients with traumatic brain injury, correlates to the severity of the disease, therefore may be an important clinical parameter to predict prognosis and provide some instructions for clinic treatment oftraumatic brain injury.