title: Cardiac troponin elevation predicts all-cause mortality in patients with acute exacerbation of chronic obstructive pulmonary disease: Systematic review and meta-analysis.
abstract: BACKGROUND
  Cardiovascular disease, especially ischemic heart disease, is a major comorbidity in chronic obstructive pulmonary disease (COPD) patients. Several studies suggested that after acute exacerbation of COPD (AECOPD), there is a significant increase of mortality (cardiac and all-cause) and of myocardial infarction. Whether cardiac troponin (Tn) elevation during AECOPD could be considered a prognostic marker of all-cause mortality is still debated.
  
  
  METHODS
  To assess the prognostic role of cardiac Tn elevation during AECOPD, we performed a systematic review and meta-analysis. We included studies with patients admitted to the hospital for AECOPD, with at least one Tn assessment and reporting the relationship (after multivariable analysis) between Tn elevation and all-cause mortality. Secondarily, studies were stratified according to: i) type of troponin (Tn I or Tn T), and ii) follow-up length (≤6 months vs. >6 months).
  
  
  RESULTS
  Ten studies were included in the systematic review and 8 in the meta-analysis. Cardiac Tn elevation ranges from 18% to 73%. We found that cardiac Tn elevation was significantly related to an increased risk for all-cause mortality (OR 1.69; 95% CI 1.25-2.29; I(2) 40%). This finding was independent to the follow-up length of studies (≤6 months: OR 3.22; 95% CI 1.31-7.91; >6 months: OR 1.38; 95% CI 1.02-1.86). Finally, Tn T seems to be more helpful in predicting all-cause mortality as compared to Tn I (OR 1.54; 95% CI 1.2-1.96 vs. OR 3.39, 95% CI 0.86-13.36, respectively).
  
  
  CONCLUSIONS
  In patients admitted to the hospital for AECOPD, cardiac Tn elevation emerged as an independent predictor of increased risk of all-cause mortality.
authors.affiliation: Cardiovascular Institute, Azienda Ospedaliero-Universitaria S. Anna, Cona (FE), Italy. Electronic address: pvsrti@unife.it.
authors.forename: Rita
authors.initials: R
authors.lastname: Pavasini
authors.affiliation: Division of Cardiology, Città della Salute e della Scienza, Turin, Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: d'Ascenzo
authors.affiliation: Cardiovascular Institute, Azienda Ospedaliero-Universitaria S. Anna, Cona (FE), Italy; Laboratorio per le Tecnologie delle Terapie Avanzate (LTTA) Center, Ferrara, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Campo
authors.affiliation: Cardiovascular Institute, Azienda Ospedaliero-Universitaria S. Anna, Cona (FE), Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Biscaglia
authors.affiliation: Cardiovascular Institute, Azienda Ospedaliero-Universitaria S. Anna, Cona (FE), Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Ferri
authors.affiliation: Research Centre on Asthma and COPD, Section of Internal and Cardio-Respiratory Medicine, University of Ferrara, Ferrara, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Contoli
authors.affiliation: Research Centre on Asthma and COPD, Section of Internal and Cardio-Respiratory Medicine, University of Ferrara, Ferrara, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Papi
authors.affiliation: Cardiovascular Institute, Azienda Ospedaliero-Universitaria S. Anna, Cona (FE), Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Ceconi
authors.affiliation: Cardiovascular Institute, Azienda Ospedaliero-Universitaria S. Anna, Cona (FE), Italy; Maria Cecilia Hospital, GVM Care & Research, Ettore Sansavini Health Science Foundation, Cotignola, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Ferrari
mesh_terms: D000208:Acute Disease; D018450:Disease Progression; D006801:Humans; D009026:Mortality / Q000639:trends; D064887:Observational Studies as Topic / Q000379:methods; D010343:Patient Admission / Q000639:trends; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood* / Q000175:diagnosis / Q000401:mortality*; D020107:Troponin T / Q000097:blood*
chemical_list: D020107:Troponin T
keywords: Chronic obstructive pulmonary disease; Exacerbation; Mortality; Outcome; Troponin