The impact of heart failure and chronic obstructive pulmonary disease on mortality in patients presenting with breathlessness

BackgroundDifferentiating heart failure from chronic obstructive pulmonary disease (COPD) in a patient presenting with breathlessness is difficult but may have implications for outcome. We investigated the prognostic impact of diagnoses of COPD and/or heart failure in consecutive patients presenting to a secondary care clinic with breathlessness.MethodsIn patients with left ventricular systolic dysfunction (LVSD) by visual estimation, N-terminal pro B-type natriuretic peptide (NTproBNP) levels and spirometry were evaluated (N=4986). Heart failure was defined as either LVSD worse than mild (heart failure with reduced ejection fraction) or LVSD mild or better and raised NTproBNP levels (>400ng/L) (heart failure with normal ejection fraction). COPD was defined as forced expiratory volume in 1s (FEV1) to forced vital capacity (FVC) ratio<0.7. The primary outcome was all-cause mortality.Results1764 (35%) patients had heart failure alone, 585 (12%) had COPD alone, 1751 (35%) had heart failure and COPD, and 886 (18%) had neither. Compared to patients with neither diagnosis, those with COPD alone [hazard ratio (HR)=1.84 95% confidence interval (CI) 1.40-2.43], heart failure alone [HR=4.40 (95% CI 3.54-5.46)] or heart failure and COPD [HR=5.44 (95% CI 4.39-6.75)] had a greater risk of death. COPD was not associated with increased risk of death in patients with heart failure on a multivariable analysis.ConclusionWhile COPD is associated with increased risk of death compared to patients with neither heart failure nor COPD, it has a negligible impact on prognosis amongst patients with heart failure.