What the new cholesterol guidelines say

Your cholesterol levels can affect your risk of heart disease and stroke. And the longer you have high cholesterol, the greater your risk.

That’s why leading medical groups recommend getting your cholesterol checked regularly, and working to lower your levels even when they’re only slightly elevated, in some cases.

Last month, the American College of Cardiology and other medical organisations released new guidelines to help patients and doctors know what cholesterol levels to aim for, and which medications might help. We asked doctors to break down the recommendations.

Know your levels

The guidelines recommend that adults, starting at age 19, have their cholesterol checked at least every five years. Before that, children should have their cholesterol checked once, between ages 9 to 11, to screen for inherited high cholesterol.

A lipid panel, which you can have done with a blood draw at your primary care doctor’s office, looks at several types of cholesterol. Of these, doctors focus most on low-density lipoprotein, or LDL, a ‘bad cholesterol’ that can build up in your artery walls.

“We have overwhelming evidence that the lower your LDL levels, the lower your risk of a cardiovascular event like a heart attack or a stroke,” said Dr Erin D Michos, associate director of preventive cardiology, Johns Hopkins University School of Medicine.

The guidelines also recommend that all adults now have levels of Lipoprotein(a), a genetically determined form of cholesterol, tested at least once. Lp(a) increases the risk of heart disease, regardless of your other lipid levels. “It’s an amplifier of whatever your risk is,” said Dr Ann Marie Navar, an associate professor of cardiology, University of Texas Southwestern Medical Center, Dallas. “We reach our adult levels in childhood, and they remain relatively stable over a lifetime, with a few exceptions.”

There’s another, less widely used test for a different lipoprotein called ApoB. “This is perhaps the best measure of cholesterol related risk because it reflects the total number of bad cholesterol particles, including not just LDL, but also Lp(a) and another type called vLDL,” Navar added.

This makes it a more reliable measure, especially for people with metabolic disease, including diabetes and cardiovascular-kidney-metabolic syndrome, because of differences in LDL particle size and density in these patients.

Individual risk

It’s never too early to talk with to doctor about your risk of heart disease. Plus, you should build heart-healthy habits like eating a Mediterranean-style or DASH diet and exercising regularly as soon as possible.

But starting at age 30, the conversation can include an actual prediction of your future risk. The guidelines use a new calculator, called PREVENT, that includes risk factors that weren’t previously taken into account, including body mass index and kidney disease. It assesses both short-term (10-year) and long-term (30-year) risk.

Measuring long-term risk is particularly useful for people 30 to 59. Doctors might look at a younger patient who isn’t at risk of heart disease in the next 10 years, but could be in the long-term, and recommend that they start taking a statin. “We want to reduce their lifetime exposure to these bad cholesterol particles,” Michos said. “The risk is not only how high a level is, it’s how many years one’s arteries are exposed to these high levels, similar to how doctors look at ‘pack-years’ of smoking.”

People who are at low 10-year risk don’t typically need to start medication, unless they have an LDL level of 160 mg/dL or greater, or have a high 30-year risk. For people who are at borderline or intermediate risk, a coronary arterial calcium (CAC) score — which uses a low-dose CT scan to look for evidence of plaque buildup in the heart arteries — can help with decision making.

“That evidence can be a powerful motivator for asymptomatic patients to take medication,” said Dr Martha Gulati, a professor of cardiology at Houston Methodist DeBakey Heart Vascular Center.

In considering treatment, doctors also take into account other factors that might raise a person’s risk of heart disease, such as South Asian race, diabetes, early menopause, pre-eclampsia or gestational diabetes, for example. They also consider inflammatory conditions like rheumatoid arthritis and psoriasis, since inflammation contributes to plaque build-up in the arteries.

Know your goal

The new guidelines give specific target levels of LDL based on short- and long-term risk of heart disease.

For general prevention of heart disease in people who are at borderline or intermediate 10-year risk and don’t have diabetes or heart disease, the goal is an LDL level under 100 mg/dL.

For patients at high 10-year risk, people with long-standing Type 2 diabetes or complications of diabetes, or people with CAC scores over 100, the goal is under 70 mg/dL.

For most patients who have already had a heart attack or a stroke, the goal is under 55 mg/dL. This might seem like an especially aggressive goal. But “with very intensive cholesterol lowering, we can actually shrink plaque,” Michos said, reducing the risk of future cardiovascular issues.

Most patients with continuously high cholesterol levels will need medication. Statins, which block the liver from making cholesterol, are still the first line of treatment. “They’re cheap. We’ve had them for over four decades. They reduce bad cardiovascular outcomes. They’re good drugs despite their bad PR,” Gulati added, referring to common concerns about side effects. “In randomised controlled trials, people who took a placebo experienced the same side effects as those who took statins.”

But there are also many other medications at doctors’ disposal. “If you try a statin and can’t tolerate it, we have other medications,” Navar said. “If you try a statin but you’re not at goal, you may need more than one medication. There are a lot of options out there.”

The New York Times