Abstract 15308: Optimal Cutpoint for BNP as a Predictor of 1-year Heart Failure-Specific Re-Hospitalization
Background: Hospitalization for heart failure (HF) is a major cause of health care expenditures. It would useful to be able to identify HF patients at the time of initial HF hospitalization who are at increased risk for re-hospitalization specifically due to HF. In this regard we sought to determine the ideal dichomotous cutpoint for brain natriuretic peptide (BNP) as a predictor of HF-specific readmission after an index HF admission.
Methods: We studied 1,170 Veterans hospitalized at our facility from January 2004 to December 2009 with an ICD-9 diagnosis code for HF as the primary diagnosis. For these analyses, patients were required to have had a BNP determination at admission, survive to discharge and either have at least one readmission specifically due to HF or survive for one-year thereafter without a HF-specific readmission. We determined how many unique patients had at least one hospital readmission specifically for heart failure in the 1st year post-discharge and assessed BNP as a predictor of HF-specific readmission. The optimal BNP cutpoint for predicting HF-specific readmission at one year was determined by examining the c-statistic for BNP values ranging from 100 to 1,000 pg/ml in steps of 100. BNP values >5,000 pg/ml were assigned the value of 5,000 pg/ml for the purposes of these analyses.
Results: HF-specific readmission occurred in 31.3% (366/1,170) within one year of discharge. Mean BNP in those with HF-specific readmit was 1,093 pg/ml vs. 897 pg/ml in those with no HF-specific readmit (p=0.002). The figure shows that a BNP cutpoint of 700 pg/ml was the optimal predictor of HF-specific readmission at 1-year (OR = 1.86; 95% CI 1.45-2.38; p<0.0001; c-statistic = 0.577).
Conclusion: Nearly one-third of patients hospitalized for heart failure will have another hospitalization specifically for heart failure within 1-year of discharge. In our population, a BNP value >700 pg/ml was the best BNP predictor of such one-year heart failure specific hospital readmissions.
- © 2011 by American Heart Association, Inc.