Do You Have the #1 Silent Killer of Women??
A Simple Test Can Help You Find Out
Every year before my annual physical, I dutifully get my blood drawn so that my doctor and I can check my cholesterol numbers. I’ve always felt somewhat protected by my high HDL score: Those high density lipoproteins act like little vacuum cleaners in the arteries, sucking up bad cholesterol from the blood vessel walls and transporting them to the liver so that they can be disposed of.
But though my HDL numbers remain stellar, my LDL or low-density lipoprotein score (representing the presence of this so-called “bad cholesterol” in my blood) has been creeping up in recent years, prompting my internist to suggest that I go on statins. This, despite the fact that when you plug my numbers into the American Heart Association’s risk calculator, I do not fall into the high-risk category. My internist points out that my escalating LDL score, coupled with my family history of heart disease, makes statins a reasonable course. But how do I know if I really need to be on lifelong medication?
Turns out, there’s a test for that. According to Joel Kahn, MD, director of the Kahn Center for Cardiac Longevity in Bingham Farms, Michigan, a Coronary Artery Calcium (CAC) scan is the single best predictor of heart disease risk, and can help tilt the scales toward or away from statin treatment.
A Newly-Recommended Predictor of Heart Disease
The CAC is a noninvasive test that uses a low-dose CT scan to take pictures of the coronary arteries. It measures calcium in the blood vessels, which is easily seen on CT. Calcium comprises about 20 percent of arterial plaque, says Dr. Kahn, so the presence of calcium is a good indicator that there is also hardened — or calcified —plaque in the vessels. A build-up of plaque can narrow the vessels, restricting blood flow and preventing parts of your body — including your heart muscle —from getting the necessary oxygen. If the plaque becomes unstable, it can also lead to a blood clot, causing a heart attack or stroke.
“You’ll find women who have silent heart disease using the CAC test, and there’s reasonably good data on the CAC score you need to treat with aspirin and statins,” says Dr. Kahn. On the other hand, he says, maybe 50 percent of women who are on statins don’t need to be. “We’re trying to identify that group of women who have no clue that they have silent artery aging going on, and be more aggressive with them — and less aggressive with the others.”
The #1 Killer Of Women
Cardiovascular disease is the number one killer of women in the United States, accounting for 1 in 3 female deaths per year, according to the American Heart Association. But in 50 percent of women with heart disease, a fatal heart attack is the first warning that they even have diseased arteries. So why haven’t more of us heard of this test?
Though the Society for Heart Attack Prevention and Eradication (SHAPE), a nonprofit grassroots group that includes leading cardiologists, has been recommending use of CAC for years, the test hasn’t been promoted as much as more expensive and invasive exams like stress tests and heart catheterizations, says Dr. Kahn, noting that the provocative 2015 documentary Widowmaker explored this dilemma. (A CAC, which typically costs between $75 and $100, is not usually covered by insurance, which may also be part of the reason it hasn’t been used that often to assess risk.) But the tide is turning.
Last year, The American Heart Association (AHA) and The American College of Cardiology (ACC) revised their guidelines on cardiovascular disease prevention, suggesting that CAC be used for patients with borderline to intermediate risk of heart disease to help inform the decision of whether to pursue statin therapy.
“Calcium scoring should be done for women who have a strong family history of heart disease and also if there are risk factors present and the decision is being made on whether or not to start medication,” says Suzanne Steinbaum, MD, national spokesperson for the American Heart Association’s Go Red for Women initiative. “In my practice, for patients with LDL cholesterol over 130 who don’t want to be on medication, I get a calcium score to sort of break that tie.”
Should You Get a CAC?
According to the AHA/ACC guidelines, CAC should be considered in patients aged 40 to 75 who are determined (via the ASCVD risk calculator) to have a 5 to 20 percent risk of developing atherosclerotic cardiovascular disease (ASCVD) over the next ten years. The guidelines stress that CAC, which confers an x-ray dose about equivalent to that of a mammogram, “is not intended as a ‘screening’ test for all,” but rather as a decision aid in those whose risk status is uncertain.
After you have a CAC scan, which takes less than 15 minutes, you will be given an “Agatston” score, which can range from 0 to 400 plus. The more calcium that is seen on the lining of the vessels, the higher the score. A score of 0 means you have no signs of calcium in your arteries.
“Any score above 0 signifies silent atherosclerosis,” says Dr. Kahn. “We know if you study people with a score of 1 to 10, they will have more heart attacks than someone with a score of 0; if they are between 10 and 100, more; 100 to 400, even more. About 10 percent will actually have a score over 1000 — they may know they have high blood pressure or diabetes, but have no clue they are suffering direct artery damage.”
Anyone with a CAC score over 100 should be on a statin, notes Dr. Steinbaum.
Statins: Should you take them?
Statins — which include drugs like Lipitor and Crestor — work by blocking the enzyme in the liver that is needed to produce cholesterol. They are designed to lower LDL and thus total cholesterol levels and are also thought to stabilize plaque so it is less likely to rupture and cause a heart attack.
Though most cardiologists consider statins the gold standard treatment for those at high risk of heart disease — and for those who have already had a heart attack, stroke, or stent — the conversation surrounding statins has at times been confusing. A December 2018 study in the Annals of Internal Medicine argued that current medical guidelines hadn’t adequately assessed the potential risks of the drugs and that half as many people should be taking statins as suggested by the guidelines. Three months later, in March of 2019, another study in the Journal of the American Heart Association found that more than half of patients who could benefit from statins do not receive them. So which is it: Are too many people on statins — or too few?
Both, says Dr. Kahn. There are many women who don’t recognize they are at high risk for heart disease — or who are resistant to taking cholesterol-lowering drugs — who would definitely benefit. But there are also women who, based on factors like age and cholesterol level, have greater than a 7.5 percent ten-year risk of developing heart disease, which traditionally would lead to a statin prescription, yet when tested with CAC turn out to have a score of 0.
Statins are not risk-free. Why treat patients who don’t have diseased arteries with a drug that has potential side effects? The most common side effect — which affects about 10 percent of patients taking the drugs — is muscle aches, though this side effect can usually be eliminated with use of a supplement called CoEnzyme Q10, by switching type of statin, or by taking a break and then restarting the drug, Dr. Steinbaum says.
Other side effects may include tingling in the hands or feet and cognitive loss or difficulty concentrating (which is reversible when medication is stopped). “At high doses, statins can cause elevated blood sugar,” says Dr. Steinbaum, though this is more likely in those who had borderline high sugar before starting the drug. In very rare instances, statins can cause serious muscle or liver damage.
Last year’s changes to the prevention guidelines call for a more nuanced conversation between physician and patient regarding statins, moving toward a more personalized approach to risk assessment. The CAC can lead to a “reassignment of risk” for many women in the gray zone, notes Dr. Kahn, to either a higher risk or lower risk category. According to the new guidelines, women who score over 100 should be on a statin; women with scores of 0 don’t need to be.
“If your CAC is over 100, you should also consider a baby aspirin a day,” says Dr. Kahn, “and do everything you can do to improve blood pressure, cholesterol, body weight, and fitness.” Women with CAC scores over 400, he says, should probably do a stress test. “The higher your calcium score, the more likely you’ll have a narrowing or a blockage in the arteries — heart symptoms in women are subtle, they can be fatigue or shortness of breath — it’s not always the crushing heart pain we educate people about.”
For women with scores between 1 and 99, says Dr. Steinbaum, “it really becomes a conversation. If I have a patient with a CAC score [of] less than 100 but with a strong family history, I would recommend a statin, but it really depends on the person.”
Another lab test that can further refine a woman’s risk, Dr. Kahn says, especially in women with a strong family history of heart disease, looks for Lipoprotein(a), an inherited form of cholesterol that significantly raises heart attack risk. According to Dr. Kahn, one out of four women inherit an elevated level of this molecule, which is to blame for 10 percent of heart attacks. The European Society of Cardiology and the European Atherosclerosis Society recently recommended that all adults be tested for lipoprotein(a) at least once, preferably around the age of 40.
Though it doesn’t take lipoprotein(a) into account, an online risk calculator at Astrocharm.org, the website of the National Space Biomedical Research Institute (as well as an Astro-CHARM phone app), can help patients who have had a CAC better understand their risk, Dr. Kahn says. It uses the CAC score, along with other risk factors, to calculate one’s risk of developing ASCVD over the next ten years. The National Heart, Lung and Blood Institute-sponsored Multi-ethnic Study of Atherosclerosis (MESA) website also offers a risk calculator that takes CAC into account.
Pursuing A Heart-Healthy Lifestyle
Experts agree that whether or not you go on a statin, a heart-healthy lifestyle —including a diet low in saturated fats and full of fruit, vegetables, and whole grains, regular exercise, and stress reduction — is crucial to preventing heart disease.
“Heart disease is a preventable disease and lifestyle is more powerful than any drug,” says Dr. Kahn. Studies have shown that low fat, high-fiber, plant-based diets (such as the Pritikin and Ornish diets) not only lower risk factors like high blood pressure, cholesterol, and blood sugar, but can even reverse plaque and, for some people, eliminate the need for medication. “Anyone who has a CAC above zero should familiarize themselves with the science of heart disease prevention and the work of Nathan Pritikin and Dean Ornish,” he says.
“The good news,” adds Dr. Kahn, who also recommends a whole food, plant-based diet in his book The Plant-Based Solution, “is that the same plant-based lifestyle that’s been shown to reduce the risk of heart disease has also been shown to reduce the risk of cancer, diabetes, and Alzheimer’s — so it’s pretty good one-stop shopping even if you focus on heart disease.”