Relationship between osteoprotegerin and mortality in decompensated heart failure with preserved ejection fraction.

Aim: The aim of this study was to evaluate whether osteoprotegerin - an emerging inflammatory biomarker in cardiovascular diseases - predicts outcomes in patients with acute heart failure and preserved ejection fraction.
Methods: We measured urea, creatinine, hemoglobin, high-sensitivity C-reactive protein, N-terminal pro-B-type natriuretic peptide and osteoprotegerin on admission in 177 patients admitted with decompensated heart failure and left ventricular ejection fraction at least 45%. The population was divided according to the median values of osteoprotegerin (158.6 ng/l). Primary and secondary endpoints were all-cause mortality and death/readmission at 1-year follow-up, respectively. Multivariable Cox models were generated for osteoprotegerin and common risk factors. We also evaluated the reclassification of patients into risk categories after adding this biomarker to the model.
Results: A total of 43 patients died during the follow-up and 84 had a combined event. Kaplan-Meier curves showed significantly increased primary and secondary endpoints according to the median of osteoprotegerin (log-rank, P < 0.0001 and 0.001, respectively). After adjustment for age, estimated glomerular filtration rate, hemoglobin, N-terminal pro-B-type natriuretic peptide, BMI and New York Heart Association III-IV, osteoprotegerin was a significant predictor of primary endpoint evaluated as continuous and categorized variable (relative risk 2.49, 95% confidence interval 1.18-5.24, P = 0.016 and relative risk 2.35, 95% confidence interval 1.11-4.96, P = 0.025, respectively). The clinical prediction model with osteoprotegerin evaluated with Net Reclassification Index was not significant.
Conclusion: Osteoprotegerin is independently associated with all-cause mortality in patients hospitalized for heart failure with preserved ejection fraction. However, adding this biomarker into a risk model does not improve its prediction value.