N-terminal pro-B-type natriuretic peptide in chronic heart failure: The impact of sex across the ejection fraction spectrum.

OBJECTIVE: The aim was to assess sex-specific differences in N-terminal B-type natriuretic peptide (NT-proBNP) regarding concentrations, predictors of high concentrations, and prognostic role, in a large and unselected population with chronic heart failure (HF) with preserved (HFpEF), mid-range (HFmrEF), and reduced ejection fraction (HFrEF).

METHODS AND RESULTS: In 9847 outpatients with HFpEF, HFmrEF, and HFrEF (49 vs. 35 vs. 25% females, respectively) from the Swedish HF Registry, median NT-proBNP concentrations were 1598 ng/L in females vs. 1310 ng/L in males in HFpEF, 1764 vs. 1464 ng/L in HFmrEF, and 2543 vs. 2226 ng/L in HFrEF (p < 0.05 for all). The differences persisted after multiple adjustment. The largest sex-difference in NT-proBNP levels was observed in HFpEF with sinus rhythm, where median concentrations were 1.4 folds higher in females (923 vs. 647 ng/L). Independent predictors of NT-proBNP levels (defined as above the different medians according to sex and HF phenotype) were overall consistent across sexes and EF. NT-proBNP levels were similarly associated with risk of all-cause death/HF hospitalization in both sexes regardless of EF.

CONCLUSION: Concentrations of NT-proBNP were higher in females across the EF spectrum, with larger relative differences in HFpEF with sinus rhythm. However, similar predictors of high levels were observed in both sexes. There were no sex-differences in the prognostic role of NT-proBNP. These findings support the use of NT-proBNP for prognostic purposes in chronic HF, regardless of sex.