Charlson Comorbidity Index can add prognostic information to Rapid Emergency Medicine Score as a predictor of long-term mortality

Abstract

To investigate whether co-existing medical disorders, summed up in a comorbidity index, in nonsurgical patients attending the emergency department could predict short-term and long-term mortality, and whether the index could add prognostic information to the Rapid Emergency Medicine Score. This was a prospective cohort study. In all, 885 nonsurgical patients, presenting to an adult emergency department and admitted to a medical department of a 1200-bed university hospital during 2 months, were enrolled consecutively. The Rapid Emergency Medicine Score (including blood pressure, oxygen saturation, respiratory rate, pulse rate, age and Glasgow coma scale) was calculated within 20 min in all those admitted to the emergency department. The history of coexisting disorders (Charlson Comorbidity Index) was collected from the medical records. In a univariate analysis, the Charlson Comorbidity Index could predict both short-term and long-term mortality in nonsurgical emergency department patients. An increase of one point in the 16-point Charlson Comorbidity Index scale was associated with a hazard ratio of 1.15 (95% CI 1.04-1.28, P<0.0001) for 7-day mortality and 1.28 (95% CI 1.23-1.33, P<0.0001) for 5-year mortality. The Rapid Emergency Medicine Score could also predict both short-term and long-term mortality (hazard ratio for an increase of one point in the 26-point Rapid Emergency Medicine Score scale was 1.33 (95% CI 1.28-1.39, P<0.0001) for 7-day mortality and 1.25 (95% CI 1.22-1.28, P<0.0001) for 5-year mortality. The Charlson Comorbidity Index could also add prognostic information to the Rapid Emergency Medicine Score as a predictor of long-term mortality, but it could not independently predict short-term (3-day, 7-day) mortality when forced into the same multivariate logistic model as the Rapid Emergency Medicine Score (hazard ratio for one point increase in the Charlson Comorbidity Index was 1.20 for 5-year mortality (95% CI 1.15-1.25, P<0.0001). Information on coexisting disorders (Charlson Comorbidity Index) can prognosticate both short-term and long-term mortality in the nonsurgical emergency department. It can also add prognostic information to the Rapid Emergency Medicine Score as a predictor of long-term mortality.