title: Relationship of Troponin T and Age- and Sex-Adjusted BNP Elevation Following Subarachnoid Hemorrhage with 30-Day Mortality.
abstract: BACKGROUND
  Troponin and brain natriuretic peptide (BNP) levels are predictors of mortality following subarachnoid hemorrhage (SAH). Prior studies used strict cutoffs for BNP elevation; however, normal levels of BNP are increased in older persons and women. We explored the association of troponin elevation and BNP elevation adjusted for sex and age with 30-day mortality.
  
  
  METHODS
  In this retrospective cohort study of patients with SAH, collected data included peak troponin T and BNP levels. Mortality data were obtained from inpatient mortality data and available records. Troponin T elevation was defined as more than 0.10 ng/mL; BNP elevation was defined as greater than the 95th percentile reference limit by age and sex for patients without cardiovascular disease. Associations of elevated troponin T and BNP were estimated from a log-binomial regression model reporting relative risks (RRs), 95 % CIs, and P values; missing data were imputed with the sample median or most frequent category.
  
  
  RESULTS
  This study included 175 SAH patients. In single-variable analysis, peak troponin T level greater than 0.10 ng/mL was associated with increased risk in 30-day mortality (RR 4.38; 95 % CI 2.43-7.89; P < .001); there was no association with elevated peak BNP adjusted for age and sex (RR 1.13; 95 % CI 0.55-2.35; P = .74). There was no evidence suggesting that the combination of elevated peak BNP and elevated peak troponin increased the risk of 30-day mortality.
  
  
  CONCLUSIONS
  Elevated troponin was an independent predictor of 30-day mortality following SAH; however, when adjusted for age and sex, elevations in BNP did not have this association.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Jacksonville, FL, USA.
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Duello
authors.forename: Jay P
authors.initials: JP
authors.lastname: Nagel
authors.forename: Colleen S
authors.initials: CS
authors.lastname: Thomas
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Blackshear
authors.forename: William D
authors.initials: WD
authors.lastname: Freeman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D013345:Subarachnoid Hemorrhage / Q000097:blood* / Q000453:epidemiology / Q000401:mortality*; D020107:Troponin T / Q000097:blood*; D055815:Young Adult
chemical_list: D020107:Troponin T; D020097:Natriuretic Peptide, Brain