Readmission and death in patients admitted with new-onset versus worsening of chronic heart failure: insights from a nationwide cohort

Aim To examine the rates of all-cause mortality and heart failure (HF) readmission in patients hospitalized with decompensated HF according to HF duration - new-onset HF and worsening of chronic HF. Methods and results In this nationwide observational cohort study, 17 176 patients were included at first hospital admission for HF in the period 2013-2015 using data from Danish nationwide registries. In total, 8860 (51.6%) patients were admitted with new-onset HF and 8316 (48.4%) with worsening of chronic HF. Patients with worsening of chronic HF were characterized by a greater comorbidity burden compared with patients with new-onset HF. The rates of outcomes were examined by multivariable Cox regression models, adjusted for age, sex, and comorbidity. Worsening of chronic HF was associated with a higher rate of the composite endpoint of all-cause mortality or HF readmission [hazard ratio (HR) 1.37, 95% confidence interval (CI) 1.31-1.43], all-cause mortality (HR 1.22, 95% CI 1.16-1.28), and HF readmission (HR 1.81, 95% CI 1.69-1.93) compared with new-onset HF. There was an interaction between atrial fibrillation (AF), HF duration, and outcome: in worsening of chronic HF, the rate of the composite endpoint was higher in patients with AF compared with those without (HR 1.12, 95% CI 1.07-1.19), whereas in new-onset HF, the rate of the composite endpoint was lower in patients with AF compared with those without (HR 0.91, 95% CI 0.85-0.96) (P-value for interaction <0.001). Conclusions Among patients hospitalized with decompensated HF, worsening of chronic HF was associated with poorer outcomes compared with new-onset HF.