Does having high cholesterol mean a heart attack is in your near future?
Maybe not, say researchers at the Minneapolis Heart Institute Foundation.
After studying more than 1,000 people who’d had heart attacks, the researchers concluded that most major heart attacks occur in people with normal cholesterol levels.
The findings were published this month in the Journal of the American Heart Association (JAMA).
Experts say that as research into heart disease continues, doctors are gaining better insight into what factors cause the disease — and finding more ways to prevent heart attacks before they happen.
Tweaking the guidelines
For many years, national guidelines on which patients should take statins, the drugs that can reduce heart disease by lowering cholesterol levels, depended on the patient’s levels of low-density lipoprotein (LDL), more commonly known as “bad” cholesterol.
While high LDL levels are associated with heart attacks, medical understanding of cholesterol as a whole and its role in cardiovascular health is still a work in progress.
“Cholesterol is a little bit of a controversial topic, as you can imagine,” Dr. Andrew Freeman, director of Cardiovascular Prevention and Wellness at National Jewish Health, and co-chair of the Nutrition and Lifestyle Work Group at the American College of Cardiology, told Healthline.
“In short, most of us would say that LDL is the ‘bad’ cholesterol and HDL, the high-density cholesterol, is the ‘good’ cholesterol. So we’ve known for a while that if we lower the LDL, cardiovascular outcomes tend to be better — less heart attacks and strokes and that kind of thing,” he said. “And when HDL is higher, people seem to have less cardiovascular events as well. This is not always the case — there were some drug trials recently that were able to raise the HDL and actually worsened outcomes. So cholesterol is probably a surrogate for something we’re not exactly sure how to measure very precisely.”
Four years ago, guidelines for prescribing statins were tweaked to reflect a person’s overall heart attack risk, rather than their cholesterol levels or whether they’d previously had a heart attack.
“Years ago, we used to go nuts about measuring everybody’s LDL and getting it down to a certain number,” said Freeman. “But more recently, in 2013, the American College of Cardiology and American Heart Association guidelines changed. So now that we put people on the appropriate drug that reduces risk, the cholesterol targets are less important, if that makes sense.”
Who gets statins?
The Minneapolis study adds weight to the 2013 guidelines that recommend statins based on overall heart attack risk, rather than cholesterol levels or whether the person had previously had a heart attack.
Continued research and better understanding of what causes heart attacks is a contributing factor into the changing guidelines. But it might not be the only one.
Dr. Ragavendra Baliga, professor of internal medicine at The Ohio State University Wexner Medical Center, and editor in chief for Heart Failure Clinics of North America, has one theory that could explain why statins were less commonly prescribed under the old guidelines.
“In those days, the statins were nongeneric. They were expensive. They were branded,” he told Healthline. “You could argue, ‘Why wait for a heart attack? Why shouldn’t everybody have the goal of having low LDL?’ But I think one of the reasons is that, whenever we do an intervention it’s risk benefit, but it’s also cost effectiveness. Ten years ago, if we’d given these branded, expensive statins to more patients, it probably would have broken the Medicare budget.”
Now that statins come in generic forms and prices have gone down, it’s no longer cost-prohibitive to prescribe them, says Baliga.
“I’m not surprised that the American Heart Association guidelines have expanded their reach to a larger population,” he said. “A., it’s inexpensive. And b., there’s a longer task record of its efficacy.”
Understanding the risk
While much of the research on cholesterol and heart attack risk can seem confusing, people can answer many of their questions with a simple trip to the doctor.
“I think everyone should have a consultation with their primary care physician to help them understand their risk factors,” said Baliga. “For example, if they have a family history of heart disease, the risk is higher. If their father had a heart attack at 30 and was a nonsmoker, then their genes are not in their favor. So a doctor might want to start statins in those patients sooner than others. Women are protected for about 10 years after menopause because of their hormones — but once again, if they are smokers or have a family history of heart disease, that changes the equation. So they all should have a consultation with their primary care physician to find out what their risk is. And further consultations can discuss if they want to make lifestyle changes, or possibly consider statin therapy.”