June 13, 2016 -- Heart experts have cast doubt on a study claiming high levels of cholesterol do not cause heart disease in older people.
The study, by an international team, also calls into question whether doctors should be prescribing cholesterol-lowering drugs called statins to people over 60.
For decades, the mainstream view has been that high levels of total cholesterol can cause heart disease.
When doctors talk about concerns over cholesterol, they are usually referring to LDL cholesterol, which is often called the “bad” cholesterol. This type of cholesterol collects on the inside walls of blood vessels, causing blockages and increasing the risk of a heart attack or stroke.
But cholesterol is an essential fat that the body needs for good health.
Reviewing the Evidence
The latest study, published in the health journal BMJ Open, examined 19 other studies involving a total of 68,094 people to find out the effect of high LDL cholesterol levels on older people.
In almost 80% of elderly people studied, those with higher levels of LDL cholesterol lived longer than those with lower levels.
The researchers say guidelines for preventing heart disease should be reviewed, "in particular because the benefits from statin treatment have been exaggerated.”
Jeremy Pearson, PhD, associate medical director at the British Heart Foundation, says he's not surprised that the researchers did not find a link between high LDL cholesterol and more deaths.
As we get older, he says, many more things affect our health. That makes it less easy to understand how high cholesterol vs. other conditions influences our risk of dying.
"In contrast, the evidence from large clinical trials demonstrates very clearly that lowering LDL cholesterol reduces our risk of death overall and from heart attacks and strokes, regardless of age,” he says. “There is nothing in the current paper to support the authors’ suggestions that the studies they reviewed cast doubt on the idea that LDL cholesterol is a major cause of heart disease or that guidelines on LDL reduction in the elderly need re-evaluating."
Tim Chico, MD, a consultant cardiologist at the University of Sheffield, says other studies have shown that lowering cholesterol with medication does reduce the risk of heart disease in the elderly.
"I am surprised the authors of this study do not refer to such trials, which tends to make their own paper disappointingly unbalanced," he says.