N E W   Y O R K, May 15 — Three times as many Americans should be taking cholesterol-lowering drugs under new aggressive guidelines to treat patients at high risk for heart disease.

STORY HIGHLIGHTS 
 
What is Cholesterol?   New HDL Levels   Diet and Exercise Important, Too   At What Cost?

The new guidelines, issued by the federal National Cholesterol Education program, recommend the use of a different test to screen for cholesterol, and add patients with diabetes to that screening because their condition poses an increased risk factor heart disease.

Heart disease remains the leading killer in the United States, with some 500,000 people dying annually.

The recommendations are expected to save lives by expanding the number of Americans being treated for high cholesterol, including raising the number on dietary treatment from about 52 million to about 65 million.

The number of those prescribed a statin, or a cholesterol-lowering drug, should also increase from about 13 million to 36 million.

"Americans at high risk for a heart attack are too often not identified and so don't receive sufficiently aggressive treatment," says Dr. Claude Lefant, the director of the National Heart, Lung and Blood Institute, which coordinates the 40 medical organizations that put together the guidelines.

What Is Cholesterol? 

Cholesterol, abundant in food sources such as eggs, shellfish, and meat, is a waxy substance found in every cell in the body.

Lefant says studies show that lowering the level of low-density lipoprotein, or LDL, the so-called "bad cholesterol" can reduce the short-term risk for heart disease by as much as 40 percent.  The aim of the new guidelines is to lower LDL.

Statin drugs that lower LDL are called HMG-CoA reductase inhibitors, such as lovastatin, provastatin and simvastatin.

An excess of LDL can build up in the walls of arteries feeding the heart and brain.  A clot that forms near the blockage can stop the flow of blood to the heart, causing a heart attack.  Strokes occur from clots that block bloodflow to or in the brain.

HDL, high-density lipoprotein — or the so-called "good" cholesterol, carries cholesterol away from the arteries and back to the liver, where it is processed.

The new guidelines recommend using a lipoprotein profile to test for high cholesterol. A lipoprotein profile measures levels of LDL, total cholesterol, HDL, and triglycerides, or other fatty substances, in the blood.

The prior recommendation called for an initial screening for only total cholesterol and HDL.

New HDL Levels 

The level at which HDL is deemed protective has been changed in the new guidelines.  A low HDL is now considered less than 40 milligrams per deciliter.  A low HDL was defined in the past as less than 35 milligrams per deciliter.

The change, the education program says, reflects increased knowledge about the relationship between a low HDL and an increased risk of heart disease.  An HDL level of above 60 milligrams per deciliter is considered protective against heart disease.

The guidelines list 200 milligrams per deciliter or less for total cholesterol as protective, and 240 or greater as very high. Optimal LDL levels are less than 100 milligrams per deciliter.

Diet and Exercise Important, Too

Fat content in the diet is an important part of the new recommendations, and include a reduction in the amount of saturated fat and cholesterol for those people with high cholesterol.

The new diet includes daily intakes of less than 7 percent of calories from saturated fat and less than 200 milligrams of dietary cholesterol.  It allows up to 35 percent of daily calories from total fat as long as most of it is unsaturated.

Exercise and weight control are also a key components of the new recommendations.  Weight control enhances drops in LDL and increases in HDL, while physical activity improves HDL and for some, LDL.

Type II diabetics have been included in the new recommendations because they are at increased risk of having a heart attack.  Type II diabetes, or noninsulin-dependent diabetes, affects more than 14 million Americans.

At What Cost?

While cardiologists interviewed by ABCNEWS.com agreed with the recommendations, they noted the issue of the cost of implementing them.

"While the focus may be on the drugs and cost, please note the new guidelines hammer away much more strongly than previously on the role of exercise and diet," says Dr. C. Noel Bairey-Merz, director, preventive and rehabilitative cardiac care center, at Cedar-Sinai Medical Center in Los Angeles.

"While most people will be treated with drugs, and therefore drug costs will go up, most people in our country die of heart disease, and heart disease also costs money.  We need to decide how we want to spend our money, now or later … I vote for now."

The guidelines are published in the latest issue of the Journal of the American Medical Association.