Importance of Heart Failure Prevention
Heart failure (HF) is a major cause of morbidity, mortality, and healthcare expense, but HF prevention has been underappreciated in global cardiovascular risk assessment and intervention within preventive cardiology. About 6.2 million adults live with HF in the United States (US), leading to a cost of approximately $30.7 billion nationally. Given the extensive health and financial costs, there is an urgent need for improved prevention of HF.
Prevention of HF is best achieved through sustained, life-long cardiovascular health, as defined by adherence to the American Heart Association's Life's Simple 7,  which is focused on the reduction of modifiable risk factors and optimization of health behaviors, specifically smoking, exercise, diet, body mass index, cholesterol, blood pressure, and glycemic control.
Coexistence of Multiple Risk Factors
A recent analysis of the Atherosclerosis Risk in Communities (ARIC) cohort led by Drs. Carine Hamo and Chiadi Ndumele et al. showed that poorly controlled risk factors are associated with increased incidence of HF (Figure 1). In this observational study, an increase in the number and severity of modifiable risk factors (hypertension, obesity, and diabetes) was associated with an increased risk of developing HF. Patients with multiple uncontrolled risk factors were at the highest risk of developing HF.
The risk factors most highly correlated with HF incidence were poorly controlled diabetes (Hgb A1c ≥8%), uncontrolled hypertension (SBP ≥160), and advanced obesity (BMI ≥35). These risk factors frequently co-exist simultaneously in patients. For example, metabolic syndrome, which includes many of the same risk factors, is present in approximately one-third of the US population, and the prevalence continues to rise. The optimization of multiple risk factors is necessary to reduce the incidence of HF for many high-risk patients.
Given the risk of poorly controlled diabetes in the development of HF, there should be a low threshold for initiation of cardioprotective diabetic medications. Specifically, cardiologists should consider early use of SGLT2 inhibitors for patients with diabetes at risk for HF, especially given the cardioprotective benefits demonstrated in the EMPA-REG OUTCOME trial.[7,8]
Importance of Primordial Prevention
Dr. Hamo et al. found that the absence of cardiovascular risk factors was associated with the lowest incidence of HF, suggesting the value of primordial prevention (the prevention of cardiovascular risk factors). This highlights the role of risk exposure in cardiovascular health. Increased exposure to cardiovascular risk factors leads to increased HF incidence, even years prior to HF diagnosis or hospitalization. Conversely, delaying or averting the onset of risk factors such as diabetes through lifestyle interventions is linked to prevention of HF. Risk factor prevention reduces cardiovascular disease burden, including HF.
Risk Factor Optimization
Another interesting conclusion from the Hamo et al. ARIC analysis was the benefit of mitigating risk factors. Patients with mildly uncontrolled risk factors had lower incidence of HF compared to those with severely uncontrolled risk factors. Thus, even partial optimization of a risk factor, such as improvement of HgbA1c, is valuable in HF prevention, even if the risk factor is not completely abolished.
Similarly, other studies have demonstrated significant benefit of initiating health behaviors; for example, the initiation of physical activity is associated with decreased risk of HF, even if exercise is started later in life. Cardiologists and primary care doctors should take the approach that "some (improvement) is better than none" when counseling patients.
Heart Failure in Cardiovascular Disease Risk Calculation
Unfortunately, current cardiovascular risk calculators do not include any estimate of risk for HF or arrhythmias such as atrial fibrillation (AF). The exclusion of HF and AF in current HF calculators leads to a systematic underestimation of cardiovascular disease risk. Quantitative risk assessments via pooled cohort equations (PCE) are key tools used in clinical practice today for effective prevention of atherosclerotic cardiovascular disease (ASCVD). However, there are significant limitations in the accuracy of these assessments, especially for patients of certain racial/ethnic groups, patients with chronic inflammatory diseases, and patients of lower socioeconomic status.
A risk calculator that includes global cardiovascular risk, including HF and AF, would be valuable to clinicians to estimate cardiovascular disease development more accurately and fully. As a hypothetical example, a 55-year-old obese patient with type 2 diabetes mellitus and a 10% risk of ASCVD may have an additional 25% risk of HF and 20% risk of AF, but these non-ASCVD risks are unaccounted for by use of the PCE alone. A cumulative estimate of global cardiovascular risk would better reflect the true burden of cardiovascular disease and would likely be more motivational for at-risk patients. Given this data from the ARIC analysis and related studies, clinicians should counsel patients on the additional risk of developing HF when discussing cardiovascular risk factors and health behaviors.
HF incidence is closely tied to the severity and extent of poorly controlled modifiable cardiovascular risk factors. Cardiologists and primary care physicians should emphasize the importance of risk factor optimization, including the early use of SGLT2 inhibitors for patients with diabetes, to reduce risk of HF. Although current cardiovascular risk calculators systemically underestimate the overall risk of cardiovascular disease by not including the risk of HF and arrhythmias, cardiologists should discuss the risk of HF while counseling patients. There is an important need for more research on risk reduction, health behavior optimization, and quantitative risk assessment of HF.
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