The significance of elevated brain natriuretic peptide levels in chronic obstructive pulmonary disease.

We investigated the clinical significance of brain natriuretic peptide (BNP), a cardiac hormone, in chronic obstructive pulmonary disease (COPD). Subjects were 38 patients with stable COPD, of whom 20 had cor pulmonale (CP), and 22 were healthy individuals. Plasma BNP levels were measured and pulmonary arterial pressure (PAP) was estimated by echocardiography. Arterial blood gas analysis, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were also recorded. BNP levels of patients with COPD were higher than those of controls (48.2 +/- 37.5 and 9.3 +/- 3.0 pg/ml). Patients with CP had a higher mean BNP level with respect to those without CP (73.9 +/- 35.8 and 21.0 +/- 10.2 pg/ml, respectively). BNP levels correlated with PAP (r = 0.68), partial arterial oxygen pressure (r = -0.70), FEV1 (r = -0.65) and FVC (r = -0.52). We have concluded that BNP determination has a role in the diagnosis of CP in patients with COPD.