title: Sustained high serum malondialdehyde levels are associated with severity and mortality in septic patients.
abstract: BACKGROUND
  There is a hyperoxidative state in sepsis. The objective of this study was to determine serum malondialdehyde (MDA) levels during the first week of follow up, whether such levels are associated with severity during the first week and whether non-surviving patients showed higher MDA levels than survivors during the first week.
  
  
  METHODS
  We performed an observational, prospective, multicenter study in six Spanish Intensive Care Units. Serum levels of MDA were measured in 328 patients (215 survivors and 113 non-survivors) with severe sepsis at days one, four and eight of diagnosis, and in 100 healthy controls. The primary endpoint was 30-day mortality and the secondary endpoint was six -month mortality. The association between continuous variables was carried out using Spearman's rank correlation coefficient. Cox regression analysis was applied to determine the independent contribution of serum MDA levels on the prediction of 30-day and 6-month mortality. Hazard ratio (HR) and 95% confidence intervals (CI) were calculated as measures of the clinical impact of the predictor variables.
  
  
  RESULTS
  We found higher serum MDA in septic patients at day one (p < 0.001), day four (p < 0.001) and day eight (p < 0.001) of diagnosis than in healthy controls. Serum MDA was lower in surviving than non-surviving septic patients at day one (p < 0.001), day four (p < 0.001) and day eight (p < 0.001). Serum MDA levels were positively correlated with lactic acid and SOFA during the first week. Finally, serum MDA levels were associated with 30-day mortality (HR = 1.05; 95% CI = 1.02-1.09; p = 0.005) and six-month mortality (hazard ratio (HR) = 1.05; 95% CI = 1.02-1.09; p = 0.003) after controlling for lactic acid levels, acute physiology and chronic health evaluation (APACHE)-II, diabetes mellitus, bloodstream infection and chronic renal failure.
  
  
  CONCLUSIONS
  To our knowledge, this is the largest series providing data on the oxidative state in septic patients to date. The novel finding is that high serum MDA levels sustained throughout the first week of follow up were associated with severity and mortality in septic patients.
authors: Leonardo
authors: L
authors: Lorente
authors: María M
authors: MM
authors: Martín
authors: Pedro
authors: P
authors: Abreu-González
authors: Alberto
authors: A
authors: Domínguez-Rodriguez
authors: Lorenzo
authors: L
authors: Labarta
authors: César
authors: C
authors: Díaz
authors: Jordi
authors: J
authors: Solé-Violán
authors: José
authors: J
authors: Ferreres
authors: Judith
authors: J
authors: Cabrera
authors: Jose Carlos
authors: JC
authors: Igeño
authors: Alejandro
authors: A
authors: Jiménez
mesh_terms: D018806:APACHE; D000368:Aged; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008315:Malondialdehyde / Q000097:blood*; D008875:Middle Aged; D009102:Multiple Organ Failure / Q000175:diagnosis; D011446:Prospective Studies; D018805:Sepsis / Q000097:blood* / Q000401:mortality*; D012720:Severity of Illness Index
chemical_list: D019344:Lactic Acid; D008315:Malondialdehyde