Natriuretic peptide plasma concentrations and risk of cardiovascular versus non-cardiovascular events in heart failure with reduced ejection fraction: Insights from the PARADIGM-HF and ATMOSPHERE trials.

Background: N-terminal pro-B-type natriuretic peptide (NT-proBNP) plasma concentrations are independent prognostic markers in patients with heart failure and reduced ejection fraction (HFrEF). Whether a differential risk association between NT-proBNP plasma concentrations and risk of cardiovascular (CV) vs non-CV adverse events exists is not well known.

Objective: To assess if there is a differential proportional risk of CV vs non-CV adverse events by NT-proBNP plasma concentrations.

Methods: In this post hoc combined analysis of PARADIGM-HF and ATMOSPHERE trials, proportion of CV vs non-CV mortality and hospitalizations were assessed by NT-proBNP levels (<400, 400-999, 1000-1999, 2000-2999, and >3000 pg/mL) at baseline using Cox regression adjusting for traditional risk factors.

Results: A total of 14,737 patients with mean age of 62 ± 8 years (24% history of atrial fibrillation [AF]) were studied. For CV deaths, the event rates per 1000 patient-years steeply increased from 33.8 in the ≤400 pg/mL group to 142.3 in the ≥3000 pg/mL group, while the non-CV death event rates modestly increased from 9.0 to 22.7, respectively. Proportion of non-CV deaths decreased across the 5 NT-proBNP groups (21.1%, 18.4%, 17.9%, 17.4%, and 13.7% respectively). Similar trend was observed for non-CV hospitalizations (46.4%, 42.6%, 42.9%, 42.0%, and 36.9% respectively). These results remained similar when stratified according to the presence of AF at baseline and prior HF hospitalization within last 12 months.

Conclusions: The absolute CV event rates per patient years of follow-up were greater and had higher stepwise increases than non-CV event rates across a broad range of NT-proBNP plasma concentrations indicating a differential risk of CV events at varying baseline NT-proBNP values. These results have implications for future design of clinical trials.