Although the basic search for the CUR domain was used to answer this question, no article of the basic search was selected to be relevant for this assessment element. Therefore, a manual search was done to find relevant information about the incidence and prevalence of the health condition as published in evidence-based guidelines and (international) reports on the HF epidemiology. European and American guidelines for the diagnosis and treatment of acute and chronic HF were consulted by doing a manual search on the website of the ESC and the American Heart Association (AHA), and the references of the ESC guidelines published in 2008 and 2012 and the AHA practice guideline published in 2013 were reviewed. These guidelines led occasionally to an additional article that was relevant for this question. Moreover, the 2015 Update of Heart Disease and Stroke Statistics of the AHA was reviewed. The website of the ESC was additionally searched for relevant studies that have been published so far on the epidemiology of HF worldwide and in developed and developing countries (search terms epidemiology OR incidence OR prevalence AND heart failure). The additional search resulted in 22 additional relevant studies. The searches for the additional studies and guidelines were additionally conducted the 06th of January 2015 by one of the investigators. Two additional studies were included during the consultation phase.

Cardiovascular disease (CVD) is the most common cause of death worldwide, being responsible for almost 30% of all deaths. In Europe CVD is responsible for 45% of all deaths equating to >4 million deaths per year, causing almost twice more deaths as cancer. Although mortality from CVD has decreased substantially in the past decade, there are wide inequalities in terms of death but also in terms of rates of treatment between (European) countries (Nicols et al., 2014; Townsend et al., 2015). {123,124} The most common forms of CVD are coronary heart disease, stroke and HF. HF is a large and global public health problem that will become more important with the aging of the world population. The number of patients with HF is predicted to increase considerably in countries with fast ageing populations. Up to one person in five is expected to develop HF at some point in their life in economically developed countries {70}. In 2007, it was already estimated that approximately 1–2 % of the adult population in developed countries had HF and that the incidence approached on average 5–10 per 1000 persons per year with a significantly higher incidence in higher age groups {82}.

In 2011, it was estimated that 26 million adults worldwide were living with HF {6}, leading some to describe it as a global pandemic {2}. Of these patients at least 15 million are European {19}, whereas almost 7 million Americans ≥ 20 years of age have HF {120}. According to the AHA, at least 850.000 patients are yearly newly diagnosed with HF in the US with the incidence approaching 1 per 100 people 65 years of age and older. According to projections of the AHA, the prevalence of HF will increase 46 % from 2012 to 2030 {83} revealing that at least an additional 3 million adults will have HF {120}. Currently, at least 5 million Americans have a clinically manifest HF {115}. Data on the incidence and prevalence of HF in the developing world are largely absent, but it is estimated that there is also an increasing number of patients with HF in the developing countries due to the emerging pandemic of cardiovascular diseases {78}. However, it is known that unlike in the US and Europe, individuals in sub-Saharan Africa countries are diagnosed with HF at a significant younger age. HF is common in South Africa, and approximately half of patients with newly diagnosed cardiovascular disease have HF, whereas only 10 % have coronary artery disease {101},{16}. Across Asia, the prevalence of HF ranges between 1.3 % and 6.7 %. According to a recent study on the global burden of ischemic heart disease {80}, HF in men was most prevalent in North America, Oceania, and Eastern Europe (> 5 per 1000). In women, the prevalence of HF was highest in Oceania, North America and North Africa and the Middle East (4.5 per 1000). HF was lowest in west sub-Saharan Africa for both men and women (< 1 per 1000). Many populations are facing a “double HF burden” caused by communicable and non-communicable diseases {80}.

HF is a condition that becomes more common with increasing age. In North America and Europe, persons 50 years of age or under are hardly ever found to have HF {32},{7},{107}, and more than 80 % are 65 years of age or older  {6}. Hence, particularly in those older than 50 years of age the prevalence and incidence increase progressively with age. In 2007 the prevalence was estimated to be 10-20 % in persons with the age between 70 and 80 while it was rising significantly to ≥10 % among persons 70 years of age or older {82}. In the Dutch Rotterdam study, the prevalence of HF was 1 % in the age group of 55-64 years, 3 % in the age group of 65-74 years and 13 % in the age group of 75-85 years {81}. Moreover, according US estimates, the remaining lifetime risk for development of new HF remains at 20 % at 80 years of age, even in the face of a much shorter life expectancy {83}.  

Overall, the prevalence of systolic HF and diastolic HF is estimated to be equal between men and women. According to the ESC (2012), at least half of patients with HF have a low or reduced ejection fraction. HF with a preserved ejection fraction or diastolic HF is present in approximately 50 % the patients with HF {77},{29}. In younger age groups, systolic HF occurs more frequently in men than in women because myocardial infarction occurs at an earlier age in men. Diastolic HF is more common in the elderly, in women, in individuals with longstanding hypertension, diabetes, renal failure, anemia, and atrial fibrillation {19}. Studies show that the accuracy of the diagnosis of HF by clinical means alone is often inadequate. This applies particularly to female, elderly, and obese patients, leading to a potential underrepresentation of the patients who have HF {106},{60},{77}.

The globally increasing prevalence of HF is not merely due to the ageing of the population. It is also due to improvements in the treatment of acute coronary syndromes, effective prevention in those at high risk or those who have already survived a first coronary event, a longer survival of cardiac patients and HF patients, and the increasing epidemiology of cardiovascular diseases in the developing countries  {84},{100},{116}. An increase in risk factors for HF such as diabetes, sedentary behavior and obesity also contribute to the increasing pool of HF patients. Factors that on the other hand decrease the incidence of HF are a decline in the number of new cases with myocardial infarction, a decline in the severity of acute myocardial infarction and the improvement of care  {40},{85}. The improvement of care for hypertension and coronary artery disease, particularly in Western Countries, also account for a decreasing incidence {86}.