Heart failure (HF) has been singled out as an epidemic and is a staggering clinical and public health problem, associated with significant mortality, morbidity, and healthcare expenditures, particularly among those aged ≥65 years. The case mix of HF is changing over time with a growing proportion of cases presenting with preserved ejection fraction for which there is no specific treatment. Despite progress in reducing HF-related mortality, hospitalizations for HF remain frequent and rates of readmissions continue to rise. To prevent hospitalizations, a comprehensive characterization of predictors of readmission in patients with HF is imperative and must integrate the impact of multimorbidity related to coexisting conditions. New models of patient-centered care that draw on community-based resources to support HF patients with complex coexisting conditions are needed to decrease hospitalizations.

The burden of heart failure and its societal cost are staggering. Approximately 4.9 million Americans have been diagnosed with the disease.¹ Hospital discharges for heart failure increased by 155% during the last 20 years, and heart failure is the most frequent cause of hospitalization in persons aged 65 years or older. Within this context, heart failure constitutes a public health problem¹ singled out as an emerging epidemic.² Although the clinical and public health importance of heart failure is undisputed, this epidemic is not adequately understood. Data on the incidence of heart failure are relatively sparse and lack consistency. Most data are derived from hospital discharge records or self-report and thus do not reflect incidence, have uncertain validity caused by documented shifts in coding practices because of reimbursement incentives,³ and cannot fully capture the burden of the disease because of the shift of care toward outpatient settings. Thus, little is known about temporal trends in the incidence of heart failure and on survival after its onset.

Designated as an emerging epidemic in 1997, heart failure (HF) remains a major clinical and public health problem. This review focuses on the most recent studies identified by searching the Medline database for publications with the subject headings HF, epidemiology, prevalence, incidence, trends between 2010 and present. Publications relevant to epidemiology and population sciences were retained for discussion in this review after reviewing abstracts for relevance to these topics. Studies of the epidemiology of HF over the past decade have improved our understanding of the HF syndrome and of its complexity. Data suggest that the incidence of HF is mostly flat or declining but that the burden of mortality and hospitalization remains mostly unabated despite significant ongoing efforts to treat and manage HF. The evolution of the case mix of HF continues to be characterized by an increasing proportion of cases with preserved ejection fraction, for which established effective treatments are mostly lacking. Major disparities in the occurrence, presentation, and outcome of HF persist particularly among younger Black men and women. These disturbing trends reflect the complexity of the HF syndrome, the insufficient mechanistic understanding of its various manifestations and presentations and the challenges of its management as a chronic disease, often integrated within a context of aging and multimorbidity. Emerging risk factors including omics science offer the promise of discovering new mechanistic pathways that lead to HF. Holistic management approaches must recognize HF as a syndemic and foster the implementation of multidisciplinary approaches to address major contributors to the persisting burden of HF including multimorbidity, aging, and social determinants of health.

Heart failure (HF) is a major clinical and public health problem owing to its high prevalence, mortality, hospitalization, and health care expenditures.¹ Accordingly, it is commonly referred to as an epidemic.^2-4 A recent statement from the American Heart Association forecasted the prevalence and cost of care of HF to increase markedly in the United States over the next decades, reflecting the aging of the population and improving patient survival.⁵ However, contemporary data on key components of this epidemic are lacking. To this end, estimates of HF incidence and its temporal trends in the population are scarce and inconsistent. Data are frequently derived from hospital discharge records, self-reports, or administrative databases^1,6-13 and cannot accurately distinguish between incident and prevalent cases, have uncertain validity because of evolving coding practices,^14-17 or cannot fully capture the burden of the disease because of the shift of care toward outpatient settings.^9,18 Moreover, because HF is a syndrome and not a disease, its diagnosis is challenging, standardized diagnostic criteria are inconsistently applied, and ejection fraction (EF) is not routinely measured, precluding the study of HF with preserved EF (HFpEF), a major component of the HF burden.^19,20 Estimates based on validated cases are outdated^21-25 and do not reflect recent changes in the key determinants of HF, such as myocardial infarction and hypertension.^26-28 Consequently, it should come as no surprise that existing results on temporal changes in HF incidence are conflicting, with reports of increasing,²³ plateau-like,²² decreasing,^7,9,13 or mixed^6,21 trends. Most important, there is no current report on trends in HF incidence according to EF. This point is critical because the determinants of these 2 conditions are likely different^29,30 and might have evolved over time. Indeed, while decreasing mortality rates after HF were reported during the 1990s to early 2000s,^7,9,13,22 the change in case mix with a growing proportion of HFpEF^26,29 (for which there is no specific treatment³¹) might have attenuated this decline. The change in case mix might also affect hospitalization rates among patients with HF, particularly in light of the major role of comorbidity, which is known to be higher in HFpEF.³² To address these gaps in knowledge, this study was designed to assess contemporary trends in the incidence of HF (validated using diagnostic criteria and categorized as reduced ejection fraction [HFrEF] or HFpEF) and cause-specific hospitalization and mortality after its onset in a geographically defined population.

Heart failure (HF) is a highly prevalent syndrome with diverse etiologies that may be associated with reduced or preserved ejection fraction (EF). The pathophysiology of HF with reduced EF has been extensively studied and management strategies are well defined.¹ Conversely, while clinical series, epidemiological surveys, and clinical trials have improved our understanding of HF and preserved EF,^2,3 controversy remains on many key elements of this entity, including its prevalence, clinical characteristics, and outcome.⁴ To this end, the prevalence and distribution of diastolic dysfunction among patients with HF and reduced or preserved EF has not, to the best of our knowledge, been reported. Further, previous studies share key limitations, including retrospective design, inclusion of prevalent cases, inconsistent assessment of EF, infrequent assessment of diastolic function, and most being hospital based.^2-4