Prognostic impact over time of ischaemic heart disease vs. non‐ischaemic heart disease in heart failure

AIMS: The aim of this study is to investigate the prognostic impact of ischaemic heart disease (IHD) in heart failure (HF) and its association to age, sex, left ventricular ejection fraction (EF), and HF duration, and furthermore, to evaluate if the impact of IHD has changed over time, in light of improved therapy. METHODS AND RESULTS: We studied 30 946 patients with non‐valvular HF, by accessing the Swedish Heart Failure Registry, from years 2000 to 2012. The mortality in 17 778 patients with clinical IHD was compared with 13 168 patients without IHD (non‐IHD). There was a significantly worse outcome in IHD, with the crude mortality of 41.1% and the event rate per 100 person‐years [95% confidence interval (CI)] of 14.8 (14.4–15.1), compared with 28.2% and 9.7 (9.4–10.0) in non‐IHD. After multivariable adjustment, the hazard ratio (HR) (95% CI) for mortality, IHD vs. non‐IHD, was 1.16 (1.11–1.22; P < 0.0001). Subgroup analyses showed significantly increased mortality in IHD, in all age subgroups, in all subgroups with EF < 50%, in both men and women, and regardless of heart failure duration more or less than 6 months. Analyses for the combination of age and EF showed the highest HR for time to death in the youngest with the lowest EF, HR (95% CI) 2.05 (1.59–2.64) for patients <60 years of age with EF < 30%. Although a numerical reduction of the HR for mortality was seen over time, the risk for mortality in IHD, compared with the non‐IHD group, was greater throughout the study period. CONCLUSIONS: In non‐valvular heart failure, IHD was associated with significantly increased mortality, compared with non‐IHD, in groups of EF below 50%, in all age groups, and regardless of sex or HF duration. The risk increase associated with EF reduction diminished with increasing age. The mortality in IHD, compared with non‐IHD, remained significantly higher throughout the 13 year study period.