N-terminal pro-B-type natriuretic peptide and B-type natriuretic peptide for identifying coronary artery disease and left ventricular hypertrophy in ambulatory chronic kidney disease patients.

Elevated natriuretic peptide levels are common in patients with chronic kidney disease (CKD), as is the presence of coronary artery disease (CAD) and left ventricular hypertrophy (LVH). It was hypothesized that N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and B-type natriuretic peptide (BNP) levels could identify CAD and LVH in asymptomatic patients with CKD. Clinical, laboratory, and echocardiographic data were collected prospectively in 54 ambulatory patients with CKD not requiring dialysis. CAD was defined by previous myocardial infarction or coronary revascularization. The median age was 70 years (interquartile range [IQR] 57 to 76). Fourteen patients (26%) had CAD, and 30 (56%) had LVH. Median NT-pro-BNP was 724 pg/ml (IQR 168 to 2,950), median BNP was 137 pg/ml (IQR 31 to 391), and the median glomerular filtration rate (GFR) was 31 ml/min/1.73 m2 (IQR 21 to 42). A strong correlation was found between NT-pro-BNP and BNP levels (R = 0.74, p <0.0001), but only moderate correlations were found between NT-pro-BNP and GFR (R = -0.45, p = 0.0006) and between BNP and GFR (R = -0.38, p = 0.005). There was no trend of an increase in the prevalence of LVH or CAD with decreasing GFR. However, across progressive NT-pro-BNP and BNP quartiles, the prevalences of LVH and CAD increased significantly. Receiver-operating characteristic curves showed that these 2 markers are similar and significant predictors for indicating LVH (area under the curve [AUC] 0.72, p = 0.005 for NT-pro-BNP; AUC 0.72, p = 0.007 for BNP) and CAD (AUC 0.80, p = 0.001 for NT-pro-BNP; AUC 0.82, p = 0.0004 for BNP; p = 0.45 for NT-pro-BNP vs BNP). In conclusion, NT-pro-BNP and BNP levels are significant and equivalent indicators of CAD and LVH in asymptomatic patients with CKD.