Association of N-terminal pro-B-type natriuretic peptide levels and mortality risk in acute myocardial infarction across body mass index categories: an observational cohort study

Table 3 Improvement in all-cause mortality risk prediction by adding NT-ProBNP to clinical models across the BMI categories

Clinical models	C-Statistics [95% CI]	△ in C-Statistics	P Value	NRI [95% CI]	IDI [95% CI]
BMI < 18.5 kg/m²
Long-term GRACE risk score	0.709 [0.637–0.781]	Reference	Reference	Reference	Reference
NT-proBNP	0.722 [0.652–0.793]	0.014	0.710	0.062 [− 0.236–0.364]	− 0.010 [− 0.149–0.153]
Long-term GRACE risk score + NT-proBNP	0.747 [0.679–0.815]	0.038	0.124	0.270 [− 0.049–0.496]	0.066 [− 0.011–0.175]
BMI 18.5–23.9 kg/m²
Long-term GRACE risk score	0.757 [0.727–0.786]	Reference	Reference	Reference	Reference
NT-proBNP	0.764 [0.735–0.794]	0.008	0.624	− 0.022 [− 0.135–0.112]	− 0.002 [− 0.058–0.057]
Long-term GRACE risk score + NT-proBNP	0.793 [0.765–0.821]	0.036	< 0.001	0.263 [0.177–0.358]	0.076 [0.043–0.116]
BMI 24–27.9 kg/m²
Long-term GRACE risk score	0.807 [0.780–0.835]	Reference	Reference	Reference	Reference
NT-proBNP	0.808 [0.781–0.835]	0.001	0.949	− 0.072 [− 0.178–0.040]	− 0.036 [− 0.096–0.024]
Long-term GRACE risk score + NT-proBNP	0.849 [0.827–0.871]	0.042	< 0.001	0.204 [0.092–0.284]	0.046 [0.019–0.079]
BMI ≥ 28 kg/m²
Long-term GRACE risk score	0.800 [0.752–0.847]	Reference	Reference	Reference	Reference
NT-proBNP	0.790 [0.748–0.832]	− 0.010	0.703	− 0.158 [− 0.316–0.032]	− 0.077 [− 0.156–− 0.002]
Long-term GRACE risk score + NT-proBNP	0.832 [0.791–0.872]	0.032	0.012	0.197 [0.063–0.340]	0.023 [0.000–0.065]

△ = difference
BMI, body mass index; CI, confidence interval; GRACE, Global Registry of Acute Coronary Events; IDI, integrated discrimination improvement; NRI, net reclassification index; NT-proBNP, N-terminal pro-B-type natriuretic peptide

ISSN: 1758-5996