OBJECTIVE: Few studies have compared midregional proatrial natriuretic peptide (MR-proANP) and N-terminal probrain natriuretic peptide (NT-proBNP). We compared their value as risk markers for all-cause mortality and cardiovascular (CV) and renal complications in individuals with type 1 diabetes.
RESEARCH DESIGN AND METHODS: MR-proANP and NT-proBNP were measured in 664 individuals. Hazard ratios (HRs) were assessed per doubling of NT-proBNP or MR-proANP for risk of a composite of ischemic events, heart failure (HF), a combined renal end point of end-stage kidney disease (ESKD), decline in estimated glomerular filtration rate (eGFR) ≥30%, and all-cause mortality or individual end points. Adjustments included CV risk factors and addition of MR-proANP or NT-proBNP.
RESULTS: Median follow-up was 5.1-6.2 years. MR-proANP was associated with higher risk of all-cause mortality (n = 57; HR 1.7, 95% CI 1.1-2.7), combined CV end point (n = 94; 1.6, 1.1-2.2), HF (n = 27; 2.8, 1.5-5.2), combined renal end point (n = 123; 1.6, 1.2-2.1), and ESKD (n = 21; 3.1, 1.2-7.8) independent of CV risk factors (P ≤ 0.02). After addition of NT-proBNP, significance for all end points was lost. A doubling of NT-proBNP was associated with higher risk of all-cause mortality (HR 1.5, 95% CI 1.2-1.8), the combined CV end point (1.3, 1.1-1.5), HF (1.7, 1.3-2.1), and the combined renal end point (1.3, 1.1-1.4) independent of CV risk factors (model 2 [P < 0.001]) and MR-proANP (model 3 [P ≤ 0.03]). There was no association with decline in eGFR ≥30% (n = 93).
CONCLUSIONS: Higher NT-proBNP was independently associated with all-cause mortality, CV disease, HF, and the combined renal end point. MR-proANP was associated with all end points but decline in eGFR, although not independent of NT-proBNP. MR-proANP may contribute to the predictive value of NT-proBNP for risk stratification in type 1 diabetes.