B-type natriuretic peptide-guided management and outcome in patients with obesity and dyspnea - results from the BASEL study

BACKGROUND: Obesity may reduce diagnostic accuracy of B-type natriuretic peptide (BNP) and affect long-term outcome. METHODS: This study evaluated patients included in the BASEL study (N = 452). We compared BNP levels in patients with (n = 86) and without (n = 366) obesity (body mass index >30 and <30 kg/m(2)) and determined sensitivities and specificities of BNP in both patient groups by receiver-operating characteristic analysis. Impact of BNP measurements on patient management and outcome in obesity, as well as 360-day mortality, was assessed. RESULTS: The BNP levels were lower in obese patients (172 pg/mL [interquartile range 31-515] vs 306 [interquartile range 75-1,040]). The optimal BNP cut-point to detect heart failure was 182 pg/mL in obese patients and 298 pg/mL nonobese patients. Obese patients had lower in-hospital mortality (3.5% vs 8.5%, P = .045) and 360-day mortality (15% vs 30%, P = .001). In obese patients, the determination of BNP levels reduced time to initiation of the appropriate treatment (96 +/- 98 vs 176 +/- 230, P > .05) without impacting other end points. CONCLUSIONS: Adjustment of BNP values in the assessment of obese patients presenting with acute dyspnea seems necessary to improve diagnostic accuracy and patient management. Obese patients had half the short- and long-term mortality of nonobese patients, independent of their final discharge diagnosis.