By Nina Agrawal
In America, heart disease remains the top cause of mortality for both men and women, a statistic that has persisted for over a century, despite significant improvements in public health.
For many years, healthcare professionals have understood that elements such as high blood pressure, elevated cholesterol, diabetes, and smoking increase the likelihood of cardiovascular disease. These variables are often utilized to assess patients’ individual risk and inform treatment decisions. However, experts have recently started to explore a wider array of factors that influence cardiovascular disease risk.
With a decrease in smoking rates and advancements in treatments for cholesterol and blood pressure, mortality rates from heart attacks and strokes have declined over the past five decades, according to Dr. Sadiya Khan, a preventive cardiologist at Northwestern University’s Feinberg School of Medicine. Nevertheless, several new challenges threaten to hinder or even reverse this progress, including the rise in metabolic disorders like obesity and diabetes, along with increasing heart failure rates.
To address these evolving concerns, the American Heart Association released a new risk assessment tool last year named PREVENT, which incorporates metrics of metabolic and kidney health and enables physicians to forecast the probability of heart failure in addition to heart attack and stroke.
“I don’t believe the primary risk factors for cardiovascular disease have fundamentally changed,” stated Dr. Michael Nanna, an interventional cardiologist at Yale School of Medicine. “However, there’s a growing acknowledgment of a broader range of risk factors than cardiologists traditionally recognized.”
The significant concerns
Conditions that contribute to plaque accumulation on the inner linings of blood vessels are a major worry. As plaques develop, they restrict the flow of blood, resulting in symptoms such as chest pain. Eventually, these plaques may dislodge and obstruct an artery supplying blood to the heart or brain, leading to a heart attack or stroke, elaborated Dr. Jeremy Sussman, an associate professor of internal medicine at the University of Michigan Medical School.
High Cholesterol: Cholesterol is a major component of plaque. While cholesterol is vital for various bodily functions, including hormone and vitamin production, excessive levels can accumulate on artery walls, merging with fat, calcium, and other substances to form plaques, explained Khan, who led the American Heart Association committee that formulated the new risk calculator.
High Blood Pressure: Hypertension can inflict damage on arteries, forcing them to become tense and lose their elasticity, which can lead to increased plaque formation, according to Khan. It also places extra strain on the heart, raising the risk of heart failure, a condition wherein the heart’s muscle fails to pump enough blood to satisfy the body’s requirements for blood and oxygen.
Age: Advancing age is considered a risk factor for heart disease primarily because the damage to blood vessels from cholesterol and blood pressure builds up over the years, noted Sussman.
Smoking: Smoking accelerates aging, according to Khan. “At the same cholesterol or blood pressure level, your blood vessels will appear worse,” she stated. This not only signifies increased plaque but also a greater chance of plaques dislodging and forming blood clots.
Furthermore, smoking induces inflammation, a recurring theme among all risk factors for heart disease, as doctors explained. Research increasingly indicates that inflammation plays a crucial role in plaque development and rupture.
Diabetes: Individuals with Type 1 or Type 2 diabetes are more prone to having elevated or imbalanced cholesterol and high blood pressure — and the combination of diabetes with these additional risk factors significantly increases the chances of heart disease, Khan indicated.
Sex: Generally, men are viewed as being at a higher risk, although heart disease is still the leading cause of death among American women, whose risk tends to rise after menopause.
Metabolic health
Heart disease risk factors rarely exist independently. “Most individuals do not just have hypertension or only diabetes,” Khan mentioned.
Acknowledging the intersection of heart disease, kidney disease, and metabolic disorders, along with their common underlying mechanisms, the American Heart Association introduced the term “cardiovascular-kidney-metabolic syndrome” last year to define this group of interconnected health issues.
A central initial contributor to developing this syndrome, as outlined in the paper that describes it, is the accumulation of excess and dysfunctional fat tissue, particularly in the abdominal area. This can trigger inflammation, insulin resistance, and eventually lead to diabetes, chronic kidney disease, and heart disease.
Consequently, the new calculator considers inputs like body mass index (a widely contested but prevalent measure of obesity) and estimated glomerular filtration rate, which evaluates kidney function.
Healthcare providers can also measure hemoglobin A1C, an indicator of average blood sugar levels over three months, as well as the urine albumin-to-creatinine ratio, which assesses kidney health to evaluate risk in a more detailed manner for high-risk patients.
Race matters
African Americans face a higher risk of mortality from cardiovascular disease compared to white Americans. On average, they tend to develop high blood pressure and diabetes four to six years earlier than their white counterparts, as noted by Khan, and they also exhibit higher rates of advanced kidney disease. South Asians and Native Americans are likewise at increased risk for cardiovascular disease, according to Nanna.
In light of these disparities, an older risk calculator utilized different formulas for Black and white individuals, with no separate options for other races due to historically limited data on these groups.
The American Heart Association eliminated race as a distinct factor in its updated risk calculator. This was done to acknowledge that race is a social construct rather than a biological determinant, Khan explained. While race continues to be relevant concerning cardiovascular risk, she added that the PREVENT equations found that racial inequalities were reflected through other risk factors, and the model accurately predicted risk across racial categories.
The calculator does account for ZIP code in an attempt to incorporate indicators of “social deprivation,” such as low income or unemployment, which can impact health outcomes.
Calculators are only one aspect
Research indicates that the new calculator on average estimates individuals’ heart disease risk to be about 50% lower than previous calculators, raising concerns that fewer people may qualify for statin or antihypertensive medication prescriptions.
However, Khan and others remarked that earlier calculators had overestimated risk based on outdated data, from periods when heart attack and stroke occurrences were higher, and they emphasized that medication thresholds might be adjusted as the new tool gains acceptance.
Regardless of the calculator employed, doctors stated that it’s essential to obtain the clearest understanding possible of heart disease risk and the potential advantages of treatment for each patient.
“Delaying action until individuals have the disease is not going to be our solution,” Khan asserted. “We need to focus on prevention.”
