title: Circulating levels of neuropeptide proenkephalin A predict outcome in patients with aneurysmal subarachnoid hemorrhage.
abstract: High plasma proenkephalin A level has been associated with ischemic stroke severity and clinical outcomes. This study aimed to assess the relationship between proenkephalin A and disease severity as well as to investigate its ability to predict long-term clinical outcome in patients with aneurysmal subarachnoid hemorrhage. Plasma proenkephalin A concentrations of one hundred and eighty patients and 180 sex- and age-matched healthy controls were measured by chemoluminescence sandwich immunoassay. Plasma proenkephalin A level was substantially higher in patients than in healthy controls (205.5±41.6 pmol/L vs. 90.8±21.1 pmol/L, P<0.001), was highly associated with World Federation of Neurological Surgeons (WFNS) score (r=0.470, P<0.001) and Fisher score (r=0.488, P<0.001), was an independent predictor for 6-month mortality [odds ratio (OR), 1.183; 95% confidence interval (CI), 1.067-1.339; P=0.004] and unfavorable outcome (Glasgow Outcome Scale score of 1-3) (OR, 1.119; 95% CI, 1.046-1.332; P=0.005) using multivariate analysis, and had high area under receiver operating characteristic curve (AUC) for prediction of 6-month mortality (AUC, 0.831; 95% CI, 0.768-0.883) and unfavorable outcome (AUC, 0.821; 95% CI, 0.757-0.874). The predictive value of the plasma proenkephalin A concentration was also similar to those of WFNS score and Fisher score (both P>0.05). In a combined logistic-regression model, proenkephalin A improved the AUCs of WFNS score and Fisher score, but the differences were not significant (both P>0.05). Thus, proenkephalin A level may be a useful, complementary tool to predict mortality and functional outcome at 6 months after aneurysmal subarachnoid hemorrhage.
authors.affiliation: The Second Zone, Department of Brain, The People's Hospital of Qingyuan, The Affiliated Qingyuan Hospital of Jinan University, B24 Xinchengyinquan Road, Qingcheng District, Qingyuan 511518, Guangdong Province, China.
authors.forename: Xiang-Lin
authors.initials: XL
authors.lastname: Chen
authors.affiliation: The Second Zone, Department of Brain, The People's Hospital of Qingyuan, The Affiliated Qingyuan Hospital of Jinan University, B24 Xinchengyinquan Road, Qingcheng District, Qingyuan 511518, Guangdong Province, China.
authors.forename: Bing-Jian
authors.initials: BJ
authors.lastname: Yu
authors.affiliation: Department of Neurosurgery, The Central Hospital of Wenzhou City, 32 Dajian Lane, Wenzhou 325000, Zhejiang Province, China. Electronic address: zhanghaiwangew@126.com.
authors.forename: Mao-Hua
authors.initials: MH
authors.lastname: Chen
mesh_terms: D000328:Adult; D004745:Enkephalins / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011498:Protein Precursors / Q000097:blood*; D013345:Subarachnoid Hemorrhage / Q000097:blood* / Q000473:pathology*
chemical_list: D004745:Enkephalins; D011498:Protein Precursors; C029992:proenkephalin
keywords: Aneurysmal subarachnoid hemorrhage; Functional outcome; Mortality; Proenkephalin A