The changing face of heart failure: are we really making progress?

Approximately 1–2% of the adult population in developed countries have heart failure (HF), with the prevalence rising to ≥ 10% among persons 70 years of age or older. HF is the single most frequent cause of hospitalization in persons 65 years of age or older, and its societal costs are enormous, thereby presenting a large public health problem. As the lives of patients with HF are prolonged by modern therapy, the prevalence of HF would be expected to increase, while morbidity and mortality rates remain high. Indeed, the incidence and prevalence of HF seem to have changed over the past decades, and in the last 10 years the first signs of a decline in incidence of HF were reported. Interestingly, this decline may be particularly true for HF patients with reduced ejection fraction (HFrEF), while the opposite may be true for HF patients with preserved ejection fraction (HFpEF). This decrease in the incidence of HFrEF may be due to the fact that while large myocardial infarctions are the primary cause of HFrEF, suchpatients are nowadays quickly treatedby primaryangioplasty, leading to smaller infarction sizes, and fewer patients with HFrEF. In this issue of the journal, Zarrinkoub and colleagues present new data on the prevalence, incidence, mortality, and survival of congestive HF in Sweden. Using high quality health registries with almost complete recording, the authors were able to identify inhabitants of Stockholm with prevalent and incident HF, as well as detailed registration of the date of death of any cause, for a period of five consecutive years. After adjustment for demographic composition, the results were also extrapolated to the entire Swedish population. In their study, the estimated prevalence of HF in Sweden was 2.2%. In absolutenumbers and foreveryage category,moremenwerediagnosed with HF, except for subjects exceding 100 years of age. The incidence of HF in 2010 was 3.7/1000 person-years in women and 3.9/ 1000 person-years in men. From 2006 to 2010, the prevalence of HF remained the same for men, whereas women showed a modest decrease. Remarkably, the incidence of HF decreased relatively by 24% during this follow-up period, and no difference was observed between men and women. There was a similar decrease in mortality by 19% for both men and women, but the 5-year survival rate after diagnosis of HF was 48% (45% in women vs. 51% in men; P , 0.05), which is still remarkably poor in the current era. Finally, hypertension was the most common cardiovascular co-morbidity, followed by ischaemic heart disease, AF and diabetes mellitus, cerebrovascular disease, and COPD. Along with the observed decreased HF incidence and improved survival (and previous epidemiological reports), the prevalence of HF remained stable during the follow-up period. Increased physician awareness of HF, and improved pharmacological and device treatment are probably responsible for this decrease. This study also shows valuable epidemiological data with regard to concomitant diseases associated with HF development (table 1, Zarrinkoub et al.). The prevalence of all co-morbidities, apart from hypertension, decreased during the follow-up period, which may explain the decrease in HF incidence. These contemporary data are valuable since they provide more insight into the incidence and prevalence of HF at the present time. Also, the investigators examined a large study population, and the quality of health registries in Stockholm appears to be high. Nevertheless, the data are limited by the fact that assessment of signs and symptoms of HF from chart review alone was retrospective, and, for example, physical findings of congestion such as jugular distention or subjective complaints of exertional dyspnoea and fatigue are easy to miss in everyday practice. Indeed, HF under-recognition is more common in patients with HFpEF, than in those with HFrEF, as the LVEF is still very important for many physicians, and, in many cases, the diagnosis of HF is not considered when the LVEF is normal. In other words, the diagnosis of HFpEF is more difficult than the diagnosis of HFrEF, because it is largely one of exclusion, i.e. potential non-cardiac causes of the patient’s symptoms (such as anaemia or chronic lung disease) must first be discounted. Also, it has been suggested that a large proportion of patients with new-onset