Comparison of B-type natriuretic peptide assays for identifying heart failure in stable elderly patients with a clinical diagnosis of chronic obstructive pulmonary disease

Aims: To compare the ability of different B-type natriuretic peptide (BNP) assays to identify heart failure in stable elderly patients with a diagnosis of chronic obstructive pulmonary disease (COPD). Methods: 200 patients aged ≥65 years with COPD according to their general practitioner and without known heart failure, underwent a diagnostic work-up. The final diagnosis of heart failure was established by a panel using the diagnostic principles of the European Society of Cardiology. All available diagnostic results, including echocardiography, but not BNP or NT-proBNP measurements, were used. The ability of different B-type natriuretic peptide assays to identify heart failure was estimated using the area under the receiver operating characteristic curves (ROC-area). Results: The ROC-areas did not differ significantly between the various assays of NT-proBNP and BNP, and ranged from 0.68 (95%CI 0.60–0.73) to 0.73 (95%CI 0.64–0.81). For NT-proBNP the age- and gender-independent “optimal” cut-point was 15 pmol/l (125 pg/ml) and for BNP 10 pmol/l (35 pg/ml). All assays were much better at excluding than detecting heart failure. Conclusions: All assays of B-type natriuretic peptide showed reasonable and comparable accuracy in recognising heart failure. At “optimal” cut-points, all assays performed better at excluding than detecting new cases of heart failure in this population.