Heart failure is on the rise in the United States, but the story behind it is more complex than you might think. A recent analysis suggests that the factors driving heart failure (HF) have significantly shifted over the past three decades. While the overall prevalence of HF has increased, the underlying causes and the characteristics of those affected have undergone a dramatic transformation. But here's where it gets controversial... Ischemic drivers, like previous heart attacks, seem to be playing a smaller role, while metabolic factors, such as obesity and diabetes, are taking center stage.
Over the last 35 years, the burden of heart failure (HF) has increased in the United States. Registry data reveals that the prevalence of HF has remained constant when adjusted for age. This suggests that the growing number of HF cases isn't necessarily because more people are developing it at any given age, but rather because the population is aging.
Researchers have noted a fascinating shift in the associated risk factors. We're seeing more obesity, diabetes, and chronic kidney disease, but less elevated blood pressure, high cholesterol, and fewer previous heart attacks. Interestingly, cardiovascular mortality has decreased in the HF population, and self-reported health and physical function have improved.
As lead author Dr. Ahmed Sayed and his colleagues point out, "These changes reflect a complex interplay between medical innovations, better implementation, and improved clinical management of some risk factors, in parallel with increasing prevalence of other risk factors over the past four decades in the United States." They emphasize that these findings have significant implications for healthcare and health policy.
Marat Fudim, MD, commented on the findings, pointing out that while the analysis sheds light on how HF prevalence has changed, it doesn't fully capture the effectiveness of current management strategies. He suggests that simply stating an increase in comorbidities and a corresponding rise in heart failure might not seem alarming. However, when considering the mortality associated with these patients, a worsening trend is observed, even with a stable age-adjusted HF prevalence.
In an accompanying editorial, Dr. John W. Ostrominski and Dr. Michael M. Givertz highlight the limitations of the analysis, including its reliance on self-reported data. They still emphasize that these findings underscore a rapid shift from ischemic to metabolic drivers of HF, which has far-reaching implications for clinical trials.
The analysis, published in JACC, included data from the National Health and Nutrition Examination Survey (NHANES), encompassing 83,552 participants. Among them, 3,078 reported a history of HF.
Between 1988 and 2023, the crude prevalence of HF rose from 2.1% to 3.0%, representing a 43% relative increase. However, when the data was adjusted for age, the prevalence remained constant. This highlights the substantial impact of age on HF prevalence estimates.
Looking closer at HF patients, the prevalence of obesity surged from 32.5% in 1988 to 60.4% in 2023. There were also increases in impaired glucose homeostasis, diabetes, and chronic kidney disease. Conversely, the proportions of HF patients with elevated blood pressure, hypercholesterolemia, and a history of heart attack decreased.
And this is the part most people miss... Certain medications, such as ACE inhibitors/ARBs, beta-blockers, and statins, were used more frequently over time. Smoking became less common. The risk of cardiovascular mortality decreased in people with and without HF. Self-reported health and physical function improved in HF patients, although work-related impairments remained unchanged.
Fudim acknowledged the limitations of the NHANES database, including missing medication and compliance data, and incomplete lab work. He also suggested further research into how HF phenotypes have changed over time. He noted that the understanding of heart failure has evolved significantly, with a rise in heart failure with preserved ejection fraction (HFpEF) and the influence of comorbidities on this phenotype.
Additionally, Fudim mentioned that the study's timeframe, which ends in 2023, might not fully reflect the impact of the COVID-19 pandemic on HF prevalence and outcomes.
The findings have significant implications for future research. The data provide a strong basis for trials targeting metabolism-, kidney-, and aging-related drivers of ventricular remodeling and disease progression. Trials targeting obesity in HF with reduced ejection fraction should also be encouraged.
The editorialists emphasize the need for more inclusivity in future studies, given that many previous HF trials have excluded patients with high BMIs and advanced chronic kidney disease. Prevention in heart failure is also a growing area of interest.
Ostrominski and Givertz conclude that the rapidly evolving needs of individuals with or at risk of HF demand parallel advancements in HF trial concepts, design, and execution. They firmly state that HF is not inevitable and that the cardiovascular community has a responsibility to demonstrate this.
Controversy & Comment Hooks: What are your thoughts on the shifting drivers of heart failure? Do you think the focus on metabolic factors is the right approach? Share your opinions in the comments below!
