Short and long term survival following hospitalization with a primary versus non-primary diagnosis of acute heart failure

Abstract Objective To compare the short-term and long-term outcomes of patients hospitalized with a primary diagnosis of acute heart failure (AHF) versus AHF associated with an alternative principal diagnosis. Methods The Israel nationwide Heart Failure (HF) survey examined prospectively 4102 consecutive HF patients admitted to all 25 public hospitals in the country. This study focused on 2302 patients hospitalized with a diagnosis of AHF. In 1594 patients, AHF was the principal diagnosis of hospitalization. In 708 patients, AHF was a secondary diagnosis with an alternative principal diagnosis of hospitalization. Results Patients with secondary diagnosis of AHF were younger with an overall less comorbidities except for concomitant ischemic heart disease. Despite that, hospital duration was longer (median days (Q1-Q3), 4 (3-7), and 6(4-9), respectively, P < 0.001) and in-hospital mortality was higher (7.2% vs. 4.9%, p-value = 0.03) among patients with a secondary diagnosis of AHF. Consistently, the age and sex adjusted OR of secondary diagnosis of AHF for in-hospital mortality was 1.76 (C.I. 1.2-2.54; p-val = 0.003). However, long-term follow-up showed a risk-reversal wherein the adjusted risk for 10-year mortality was significantly lower among those hospitalized with a secondary vs. primary diagnosis of AHF (HR = 0.88, C.I. 0.79-0.99; p-val = 0.04). Conclusions While hospitalization with secondary diagnosis of AHF is associated with a higher risk for in-hospital mortality in comparison to hospitalization with principal diagnosis of AHF, it is independently associated with a lower risk for 10-year mortality. These findings may have implications for short and long term risk stratification after AHF hospitalization.