Diabetes mellitus status modifies the association between N-terminal B-type natriuretic peptide and all-cause mortality risk in ischemic heart failure: a prospective cohort study

BACKGROUND: N-terminal B-type natriuretic peptide (NT-proBNP) discriminates mortality risk in diabetes mellitus (DM) and in heart failure (HF) populations. Whether DM status modifies the association between NT-proBNP and all-cause mortality risk in ischemic HF is unknown. METHODS: This was a single-center, prospective cohort study conducted with 2287 ischemic HF patients. Subjects were divided into with DM group and without DM group. Multivariate Cox proportional-hazards models were conducted to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs). The product of DM status and NT-proBNP were used to assess the interaction. Propensity score matching analysis was used to verify the robustness of the results. RESULTS: Of 2287 ischemic HF participants, 1172 (51.2%) had DM. After a median follow-up of 3.19 years (7287 person-years), 479 (20.9%) of the participants died. After adjusting for the covariates, continuous NT-proBNP was more prominently associated with risk of mortality in HF patients with DM (HR: 1.65, 95% CI: 1.43–1.91) than those without (HR: 1.28, 95% CI: 1.09–1.50). A significant interaction of DM status and NT-proBNP was observed (P-interaction = 0.016). The relationships were consistent when NT-proBNP was considered as a categorical variable and in the propensity matching analysis. CONCLUSIONS: DM status modified the association between NT-proBNP and all-cause mortality in ischemic HF patients, suggesting that NT-proBNP was more prominently associated with risk of mortality in patients with DM than those without. Future studies to clarify the mechanisms underlying these observations are needed. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13098-023-01046-5.