title: Validated Risk Score for Predicting 6-Month Mortality in Infective Endocarditis.
abstract: BACKGROUND
  Host factors and complications have been associated with higher mortality in infective endocarditis (IE). We sought to develop and validate a model of clinical characteristics to predict 6-month mortality in IE.
  
  
  RESULTS
  Using a large multinational prospective registry of definite IE (International Collaboration on Endocarditis [ICE]-Prospective Cohort Study [PCS], 2000-2006, n=4049), a model to predict 6-month survival was developed by Cox proportional hazards modeling with inverse probability weighting for surgery treatment and was internally validated by the bootstrapping method. This model was externally validated in an independent prospective registry (ICE-PLUS, 2008-2012, n=1197). The 6-month mortality was 971 of 4049 (24.0%) in the ICE-PCS cohort and 342 of 1197 (28.6%) in the ICE-PLUS cohort. Surgery during the index hospitalization was performed in 48.1% and 54.0% of the cohorts, respectively. In the derivation model, variables related to host factors (age, dialysis), IE characteristics (prosthetic or nosocomial IE, causative organism, left-sided valve vegetation), and IE complications (severe heart failure, stroke, paravalvular complication, and persistent bacteremia) were independently associated with 6-month mortality, and surgery was associated with a lower risk of mortality (Harrell's C statistic 0.715). In the validation model, these variables had similar hazard ratios (Harrell's C statistic 0.682), with a similar, independent benefit of surgery (hazard ratio 0.74, 95% CI 0.62-0.89). A simplified risk model was developed by weight adjustment of these variables.
  
  
  CONCLUSIONS
  Six-month mortality after IE is ≈25% and is predicted by host factors, IE characteristics, and IE complications. Surgery during the index hospitalization is associated with lower mortality but is performed less frequently in the highest risk patients. A simplified risk model may be used to identify specific risk subgroups in IE.
authors.affiliation: Duke University Medical Center, Durham, NC.
authors.forename: Lawrence P
authors.initials: LP
authors.lastname: Park
authors.affiliation: Duke University Medical Center, Durham, NC.
authors.forename: Vivian H
authors.initials: VH
authors.lastname: Chu
authors.affiliation: UT-Southwestern Medical Center, Dallas, TX.
authors.forename: Gail
authors.initials: G
authors.lastname: Peterson
authors.affiliation: 5th Department of Medicine and Infectious Diseases Unit, "Evangelismos" General Hospital, Athens, Greece.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Skoutelis
authors.affiliation: Medical Centre Ljublijana, Ljublijana, Slovenia.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Lejko-Zupa
authors.affiliation: Hospital General Universitario Gregorio Marañón, Madrid, Spain.
authors.forename: Emilio
authors.initials: E
authors.lastname: Bouza
authors.affiliation: Maladies Infectieuses et Réanimation Médicale, Rennes, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Tattevin
authors.affiliation: Faculté de Médecine de Marseille, Marseille, France.
authors.forename: Gilbert
authors.initials: G
authors.lastname: Habib
authors.affiliation: The Canberra Hospital, Woden, Australia.
authors.forename: Ren
authors.initials: R
authors.lastname: Tan
authors.affiliation: Clinica Cardio VID, Medellín, Colombia.
authors.forename: Javier
authors.initials: J
authors.lastname: Gonzalez
authors.affiliation: Sanatorio de la Trinidad Mitre, Buenos Aires, Argentina.
authors.forename: Javier
authors.initials: J
authors.lastname: Altclas
authors.affiliation: King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia.
authors.forename: Jameela
authors.initials: J
authors.lastname: Edathodu
authors.affiliation: Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Claudio Querido
authors.initials: CQ
authors.lastname: Fortes
authors.affiliation: Heart Institute (InCor), University of Sao Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Rinaldo Focaccia
authors.initials: RF
authors.lastname: Siciliano
authors.affiliation: Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Orathai
authors.initials: O
authors.lastname: Pachirat
authors.affiliation: American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Souha
authors.initials: S
authors.lastname: Kanj
authors.affiliation: Duke University Medical Center, Durham, NC a.wang@duke.edu a.wang@dm.duke.edu.
authors.forename: Andrew
authors.initials: A
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D004696:Endocarditis / Q000401:mortality*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D057216:Propensity Score; D012042:Registries; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity
keywords: infection; mortality; prognosis; surgery; valves