Expanding the fight against heart disease

By Alvin Powell | Harvard Staff Writer | Harvard Gazette

Experts welcome the shift to more aggressive recommendations

U.S. medical organizations are seeking to reduce deaths from heart disease, the nation’s No. 1 killer, with new guidelines that reframe prevention as a lifelong battle that starts with screening in childhood.

Changes were made Clinical practice guidelines issued last month by the American Heart Association, the American College of Cardiology and several other professional organizations.

In this edited conversation, Ramit BhattacharyaMas General, instructor of medicine at Harvard Medical School and associate director of the hospital’s Cardiac Lifestyle Program, discusses the relevant science, the potential impact of new treatment thresholds, and more.

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How different are these guidelines from the 2018 recommendations?

They did a fantastic job and put together new data from the past 10 years incorporating information that cardiologists have been using for some time now.

Major changes are formal integration of coronary artery calcium scoring, formal integration of polygenic risk scoring, explicit recommendations for Lp(a) screening, and more formal involvement of apolipoprotein B as a risk measure. The guidelines also call out special populations that may benefit from additional care: people with obesity and diabetes, people with chronic kidney disease, hypertensive disorders of pregnancy and other reproductive risk factors, people with high genetic risk, and people of high-risk ancestry — including South Asians and Filipinos — who have now been named. It is an attempt to move toward more holistic care based on an understanding of the risks that most people face, and then, in a more personalized manner, to address groups that are at additional high risk.

Some of these new measures, including LP(A) and coronary artery calcium, may be unfamiliar to patients. What do they tell us that we didn’t know before?

Apolipoprotein B and Lp(a) are additional types of cholesterol – or ways to measure cholesterol that help us refine our risk. We discovered that Lp(a) is a cousin of the LDL-C molecule and is atherogenic, meaning it leads to the development of Atherosclerosis. It’s about six times stickier than LDL, but luckily it’s not very high in most people. However, Lp(a) is elevated in 20 percent of the population, and that elevation increases cardiovascular risk. Unfortunately, it is inherited. You can’t eat healthy to reduce it, you can’t exercise to keep it away, or you can’t stop smoking to reduce it. But when I check Lp(a), it helps me see when I should lower the treatment threshold and treat you more aggressively to improve your immune outcomes. We have several new therapeutics in clinical trials that will help patients with high Lp(a) reduce their risk. And if I can tell you that your high Lp(a), you are empowered to make better decisions about your health — eat better, exercise more, etc.

If someone turns 35 today, I want to know what their arteries will look like at 65, not just in the next decade.

Is the treatment threshold lower than in the past?

Yes, and the process is worth explaining. Older risk calculators — integrated equations — predicted risks of about 40 to 50 percent for many patients. The new guidelines move to a well-calibrated tool called Resistance CalculatorMore than 3 million contemporary Americans have been trained and lowered treatment thresholds accordingly: the old cutoff was 5 percent predicted 10-year risk; The new one is 3 percent.

That doesn’t mean everyone above 3 percent is automatically medicated — that’s where the conversation begins. Anyone who comes in at 4 or 5 percent can see targeted lifestyle changes — improving their diet, exercising regularly, losing weight, quitting smoking, getting better sleep — lower that number on their own, without ever needing a pill. That is actually the ideal result. Your doctor will weigh all of this, along with your family history and other test results, before recommending treatment.

For an individual patient these numbers may sound abstract, but at the population level, this recalibration is important. And importantly, PREVENT also predicts 30-year risk, which is the time horizon where prevention really pays off. If someone turns 35 today, I want to know what their arteries will look like at 65, not just in the next decade. If we think 20 or 30 years out, we have the greatest ability to prevent disease, where even modest interventions can dramatically change the trajectory of someone’s health.

And the guidelines call for testing at a much younger age, right?

yes Guidelines now recommend that risk assessment begin at 30 — not 40 or 50 — and for adults in their 30s with elevated cholesterol and adequate predicted risk, pharmacotherapy is on the table. This is a meaningful change. D Cholesterol Treatment Trialists’ Companion — a large pooled analysis of statin trials — showed that the absolute benefit of lowering LDL accumulates over time, meaning that earlier treatment translates into a much larger lifetime reduction in risk. The old message was, “You’re in your 20s. Don’t worry about it until you’re 50.” But cardiovascular disease doesn’t work that way. Investments you make early pay the biggest dividends, and by your 50s or 60s you’re playing catch-up.

Separately, in children, these guidelines recommend early testing to improve diagnosis of genetic conditions — such as heterozygous familial cholesterolemia, which affects about one in 250 people and carries a two- to fourfold lifetime risk of heart disease, yet up to 90 percent of those affected go undiagnosed. Universal lipid screening is now recommended at ages 9 to 11, and cascade screening — testing close relatives of someone already screened — can begin before age 2. The window is important because family history alone misses up to half of cases, and the sooner you catch it, the more lifelong risk you can take off the table.

About 80 percent of cardiovascular disease is preventable through lifestyle and behavior changes.

Has the lack of a long-term approach been part of the reason it has been so difficult to knock out cardiovascular disease as a leading killer?

That’s a big component. About 80 percent of cardiovascular disease is preventable through lifestyle and behavior changes. And these guidelines aren’t just for individuals, they’re for society: municipal governments, federal governments, and policymakers. They should read and think: “How can I support my population in a way that makes it easier to live these healthy lives?” Americans are juggling a lot of things right now: extra jobs, the gig economy, taking care of kids, etc. I see people in my clinic struggling. When I say, “And exercise two hours a week, and eat it, and cook your meals at home” – that’s too much. We should think about how we can help our patients and our colleagues and our friends make healthy decisions so that they don’t have to read instructions to know what to do.

My father had a coronary bypass a few years ago. How will this guide help him?

Sometimes we check someone’s health and months or years later, they have a heart attack and say, “I went to my doctor and everything was fine. How could this be?” This happens because we used to diagnose coronary artery disease only when someone had a heart attack or had to have a stent or bypass surgery.

Imagine instead if you are middle-aged and your doctor says you may be in the intermediate risk category and recommends a coronary calcium scan to see what your arteries are like. The new guidelines specify that when any calcium is present, you should be treated with preventive medicine to reduce your risk of heart attack. And if the calcium starts to rise, we get aggressive and we treat you like you’ve already had a heart attack. We want to lower your cholesterol to the floor and improve all your other risk factors. If your father had known about his coronary calcium years before his bypass, he would have been able to stay on preventive medicine and may never have had the procedure.

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This is the story is reprinted with permission From the Harvard Gazette.

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