title: Total antioxidant capacity is associated with mortality of patients with severe traumatic brain injury.
abstract: BACKGROUND
  Previously, circulating total antioxidant capacity (TAC) in traumatic brain injury (TBI) patients has been scarcely studied and only in studies of small sample size (lower than 55 TBI patients). In one study were found higher serum TAC in non-survivor than in survivor TBI patients; however, an association between circulating TAC and mortality in patients with TBI has not been previously reported. Thus, the objective of this study was to determine whether there is an association between circulating TAC, peroxidation state and mortality in patients with severe TBI.
  
  
  METHODS
  This was a multicenter, observational and prospective study was carried out in six Spanish Intensive Care Units. We included patients with severe TBI defined as Glasgow Coma Scale (GCS) lower than 9. We excluded patients with Injury Severity Score (ISS) in non-cranial aspects higher than 9. We measured serum TAC on day 1 of TBI. The 30-day mortality was established as endpoint.
  
  
  RESULTS
  Non-surviving TBI patients (N = 27) showed higher serum TAC (P < 0.001) than survivor ones (N = 73). Logistic regression analyses showed that serum TAC higher than 2.59 nmol/mL were associated with 30-day mortality controlling for APACHE-II and CT classification (OR = 4.40; 95% CI = 1.14-16.98; P = 0.03), controlling for GCS and age (OR = 5.88; 95% CI = 1.57-22.06; P = 0.009), and controlling for CT classification and admission abnormal pupils (OR = 3.89; 95% CI = 1.30-11.61; P = 0.02). There was an association between serum TAC and malondialdehyde (a biomarker of lipid peroxidation) levels (rho = 0.25; p = 0.01), APACHE-II score (rho = 0.23; p = 0.03) and GCS (rho = -0.21; p = 0.04).
  
  
  CONCLUSIONS
  To our knowledge, our series is the largest reporting data on circulating TAC in patients with severe TBI. The most relevant and new findings of our study were that there is an association between circulating TAC and peroxidation state and mortality in patients with severe TBI.
authors.affiliation: Intensive Care Unit, Hospital Universitario de Canarias, Ofra, s/n. La Laguna, 38320, Santa Cruz de Tenerife, Spain. lorentemartin@msn.com.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Lorente
authors.affiliation: Intensive Care Unit, Hospital Universitario Nuestra Señora de Candelaria, Crta del Rosario s/n, Santa Cruz de Tenerife, 38010, Spain. mar.martinvelasco@gmail.com.
authors.forename: María M
authors.initials: MM
authors.lastname: Martín
authors.affiliation: Unidad de Genética. Instituto de Enfermedades Tropicales y Salud Pública de Canarias, Universidad de La Laguna, Campus de Anchieta, Avda. Astrofísico Francisco Sánchez s/n, La Laguna, Tenerife, 38071, Spain. tacosalm@ull.edu.es.
authors.forename: Teresa
authors.initials: T
authors.lastname: Almeida
authors.affiliation: Deparment of Phisiology. Faculty of Medicine, University of the La Laguna, Santa Cruz de Tenerife, Spain. pabreu@ull.es.
authors.forename: Pedro
authors.initials: P
authors.lastname: Abreu-González
authors.affiliation: Intensive Care Unit, Hospital General La Palma, Buenavista de Arriba s/n, Breña Alta, La Palma, 38713, Spain. lramosgomez@gmail.com.
authors.forename: Luis
authors.initials: L
authors.lastname: Ramos
authors.affiliation: Intensive Care Unit, Hospital Clínico Universitario de Valencia, Avda. Blasco Ibáñez n°17-19, Valencia, 46004, Spain. moni_begasa@hotmail.com.
authors.forename: Mónica
authors.initials: M
authors.lastname: Argueso
authors.affiliation: Servicio de Bioquímica Clínica, Complejo Hospitalario Universitario Insular Materno-Infantil, Plaza Dr. Pasteur s/n, Las Palmas de Gran Canaria, 35016, Spain. mriarui@gobiernodecanarias.org.
authors.forename: Marta
authors.initials: M
authors.lastname: Riaño-Ruiz
authors.affiliation: Intensive Care Unit, Hospital Universitario Dr. Negrín, CIBERES, Barranco de la Ballena s/n, Las Palmas de Gran Canaria, 35010, Spain. jsolvio@gobiernodecanarias.org.
authors.forename: Jordi
authors.initials: J
authors.lastname: Solé-Violán
authors.affiliation: Research Unit, Hospital Universitario de Canarias, Ofra, s/n. La Laguna, 38320, Santa Cruz de Tenerife, Spain. ajimenezsosa@gmail.com.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Jiménez
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000737:chemistry*; D015415:Biomarkers / Q000097:blood; D001930:Brain Injuries / Q000097:blood* / Q000401:mortality*; D015331:Cohort Studies; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood* / Q000737:chemistry; D011446:Prospective Studies; D012044:Regression Analysis; D013030:Spain; D017741:Survivors
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D010100:Oxygen