Development and validation of a time-dependent risk model for predicting mortality in infective endocarditis

Eur Heart J. 2011 Aug;32(16):2016-26. doi: 10.1093/eurheartj/ehp085. Epub 2009 Mar 28.


Aims: Existing risk models in infective endocarditis (IE) have not investigated whether the prognostic value of clinical parameters is time-dependent. We have explored the potential of time-dependent risk stratification to predict outcome in IE.

Methods and results: We studied 273 patients admitted with IE to two centres (derivation cohort n=192, validation cohort n=81). The derivation cohort was used to identify independent predictors of 6 months mortality at days 1, 8, and 15 (multivariable Cox regression, P<0.05). There were six predictors at day 1, five at day 8, and only three at day 15. Whereas heart failure, thrombocytopenia, and severe comorbidity predicted mortality at all three time-points, other predictors were time-dependent (age, tachycardia, renal impairment at day 1; severe embolic events, renal impairment at day 8). These predictors were incorporated into a time-dependent model. The model was validated in an independent cohort with concordance indices of 0.79 (95% CI 0.68-0.91) at day 1, 0.79 (95% CI 0.65-0.93) at day 8, and 0.84 (95% CI 0.73-0.95) at day 15. Six months mortality was 2.4% in patients deemed as low-risk at all time-points, compared with 78.2% in patients classified as high-risk at any evaluation.

Conclusion: Prognostic factors in IE are time-dependent. Time-dependent risk stratification accurately predicts outcome in IE.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Adult
  • Aged
  • Embolism / mortality
  • Endocarditis, Bacterial / mortality*
  • Endocarditis, Bacterial / surgery
  • Epidemiologic Methods
  • Female
  • Heart Failure / mortality
  • Hospitalization / statistics & numerical data
  • Humans
  • Kidney Diseases / mortality
  • Male
  • Middle Aged
  • Prognosis
  • Tachycardia / mortality
  • Thrombocytopenia / mortality
  • Time Factors