No Clear Evidence for Ultra-Low Cholesterol Targets?

Americans have been trying to get their cholesterol levels down for decades, ever since studies showed a strong link between high cholesterol and heart disease. But in recent years, experts have suggested that some people should aim even lower, recently recommending very low levels of the type of cholesterol called low-density lipoprotein for some high-risk people - even if it means they had to take multiple medications to get there.

Not so fast, says a team of researchers from the VA Ann Arbor Healthcare System and the University of Michigan Health System in a new paper in the October Annals of Internal Medicine.

After performing an exhaustive review of existing research on LDL cholesterol and heart health, they conclude that there is no scientifically valid evidence to support the ultra-low LDL target of 70 milligrams/deciliter for very high-risk patients that has been advocated by some members of the federal government's National Cholesterol Education Program. Further, they suggest that the evidence previously cited to support an LDL goal of less than 100mg/dL for high risk patients also has major flaws.

That evidence may come someday, but until that day, it may be better for society to concentrate less on cholesterol and more on getting people with multiple heart disease risk factors on medications called statins - regardless of their cholesterol levels. Statins are great at lowering a person's LDL cholesterol, but it is not yet clear if lowering cholesterol is the main reason that statins prevent heart attacks and save lives. A focus on statin therapy may provide more public benefit than focusing on getting high-risk patients' levels as low as they can go using multiple drugs.

"Our review suggests that we in the medical community have misunderstood the scientific evidence on whether very low LDL is important, or whether adequate doses of statins are what is really important," says lead author Rodney Hayward, M.D., director of the VA Center for Health Services Research and Development and professor of internal medicine at the U-M Medical School. "Current practice guidelines and recommendations often focus on getting LDL as low as possible, but the literature to date doesn't demonstrate that low LDL is what is truly important - but it does show that statins save lives in high cardiac risk patients regardless of a person's LDL level."

In fact, Hayward and his colleagues say, it may be that the other effects of statin drugs help reduce the risk of heart disease and heart attacks as much or more than the drugs' LDL-lowering power does. Statins inhibit inflammation and clotting, as well as reduce cholesterol, attributes that can be important for preventing heart attacks.

People who have survived a heart attack or have risk factors that put them at high risk of future heart problems should probably be on a moderate or high dose of a statin and stay on it no matter what happens to their exact LDL level, Hayward says.