title: Prognostic value of neuropeptide proenkephalin A in patients with severe traumatic brain injury.
abstract: High plasma proenkephalin A levels have been associated with poor clinical outcome of aneurysmal subarachnoid hemorrhage. This prospective observatory study was designed to investigate the relationship between plasma proenkephalin A levels and 1-week mortality, 6-month mortality and 6-month unfavorable outcome (defined as Glasgow Outcome Scale score of 1-3) in patients with severe traumatic brain injury. This study recruited 128 patients and 128 sex- and age-matched healthy controls. Plasma proenkephalin A levels, as measured by chemoluminescence sandwich immunoassay, were statistically significantly higher in patients than in healthy controls (239.1±93.0 pmol/L vs.81.3±22.1 pmol/L; P<0.001) and were correlated with Glasgow Coma Scale scores (r=-0.540, P<0.001). It was identified as an independent prognostic predictor of 1-week mortality [odds ratio (OR), 1.214; 95% confidence interval (CI), 1.103-1.425; P<0.001], 6-month mortality (OR, 1.162; 95% CI, 1.101-1.372; P<0.001) and 6-month unfavorable outcome (OR, 1.116; 95% CI, 1.097-1.281; P<0.001). Moreover, it had high predictive value for 1-week mortality [area under curve (AUC), 0.852; 95% CI, 0.778-0.908], 6-month mortality (AUC, 0.841; 95% CI, 0.766-0.899) and 6-month unfavorable outcome (AUC, 0.830; 95% CI, 0.754-0.891). Furthermore, its predictive value was similar to Glasgow Coma Scale score's (all P>0.05). Yet, a combined logistic-regression model did not show that it statistically significantly improved the predictive value of Glasgow Coma Scale score (all P>0.05). Thus, it was proposed that enhanced plasma proenkephalin A could be a useful, complementary tool to predict short- or long-term clinical outcome after severe traumatic brain injury.
authors.affiliation: Department of Emergency Medicine, Fuyang People's Hospital, 2-4 Guihua Road, Fuyang 311400, Zhejiang Province, China. Electronic address: FangLongZhu@yeah.net.
authors.forename: Jian-Bo
authors.initials: JB
authors.lastname: Gao
authors.affiliation: Department of Critical Care Medicine, Fuyang People's Hospital, 2-4 Guihua Road, Fuyang 311400, Zhejiang Province, China.
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Tang
authors.affiliation: Department of Emergency Medicine, Fuyang People's Hospital, 2-4 Guihua Road, Fuyang 311400, Zhejiang Province, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Fuyang People's Hospital, 2-4 Guihua Road, Fuyang 311400, Zhejiang Province, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Shen
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000097:blood* / Q000401:mortality* / Q000473:pathology; D018572:Disease-Free Survival; D004745:Enkephalins / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D015996:Survival Rate; D013997:Time Factors; D015599:Trauma Severity Indices
chemical_list: D004745:Enkephalins; D011498:Protein Precursors; C029992:proenkephalin
keywords: Clinical outcome; Proenkephalin A; Traumatic brain injury