Prognostic value of extreme NT-proBNP levels in patients hospitalized for heart failure

Background and objective

To evaluate the prognostic value of extreme levels of the N-terminal pro-B-type natriuretic peptide (NT-proBNP) measured at any time during hospitalization for heart failure (HF).

Materials and methods

A retrospective cohort study including patients hospitalized for HF in a secondary-level hospital with at least one NT-proBNP measurement. Two groups were defined: patients with extreme NT-proBNP levels (>50,000 pg/ml) and those with elevated NT-proBNP levels (>1800 pg/ml and <20,000 pg/ml). The primary outcome was a composite of (1) in-hospital mortality, (2) HF readmission, and (3) six-month mortality. Cox survival models were used for analysis.

Results

A total of 83 patients with extreme NT-proBNP levels and 100 with elevated NT-proBNP levels were included; 61% were women, with a median age of 87 years. Comorbidity burden was high and similar between groups (median Charlson index: 8). The primary outcome was more frequent in patients with extreme NT-proBNP levels: 25.02 vs. 10.53 events per 100 patient-months (HR 2.07; 95% CI: 1.37–3.14). Both in-hospital and six-month mortality were significantly higher in the extreme NT-proBNP group, while HF readmissions were numerically higher but not statistically significant. These results remained consistent after multivariable adjustment.

Conclusions

Patients hospitalized for HF with NT-proBNP levels > 50,000 pg/ml have a worse prognosis than those with NT-proBNP < 20,000 pg/ml, representing a high-risk subgroup with short-term mortality.