A simple prognostic model for assessing in-hospital mortality risk in patients with acutely decompensated heart failure

Abstract

Background An assessing of the in-hospital mortality risk for an emergency hospitalized patient with acutely decompensated heart failure (ADHF) is challenging task. Simple formula can help.

Methods On the base of six indicators identified in derivation group, simple formula for assessing the risk for in-hospital mortality of ADHF patients was derived and later tested in validation group.

Results The retrospective analysis of a derivation group (533 survivors, 121 deceased) identified six risk indicators: age, heart rate (HR), systolic blood pressure (SBP) and serum concentrations of urea, sodium (Na) and uric acid (UA). The final formula was created ([age/10]²× HR/SBP)+(Urea-Na/10)+UA/100 and formula result of 53 was established as cut-off result. In the derivation group, at the cut-off point of 53, area under the ROC curve (AUC) was 0.741 (95% CI 0.701–0.776); with sensitivity 54% and specificity 83%. The discriminative capacity of the formula was significantly higher than each of its components. In the validation group of 591 patients (527 survived, 64 died) AUC was also 0.741 (95% CI 0.706–0.774), sensitivity was 66% and specificity 76%. Positive predictive value (PPV) of the developed formula was modest (34%), but negative predictive value (NPV) was 95%. N-terminal pro-B type natriuretic peptide and troponin I were determined, but not included into formula.

Conclusions The developed formula enables simple, rapid and inexpensive risk assessment, but its disadvantage is a low PPV. However, a high NPV permits the identification of patients with a low risk of in-hospital mortality, which could lead to a more rational patient treatment.

Keywords:

• Heart failure
• mortality
• prognostic model