Cholesterol guidelines released.

Cholesterol guidelines released

The National Heart, Lung and Blood Institute's (NHLBI) National Cholesterol Education Program last week issued a report telling physicians how to evaluate and treat adults with high blood cholesterol, including those in various risk groups.

"This is the first time we have had this level of practical advice produced by a national panel reaching consensus recommendations,' said program coordinator James Cleeman at the Oct. 5 news conference announcing the report.

The report establishes lower cutoffs for high cholesterol than the ones currently being used, thus putting about one of four U.S. adults, or 40 million people, in the "high cholesterol' range (240 milligrams per deciliter of blood and above). The "borderline high' range is 200 to 239 mg/dl.

But because of the lower cutoffs, improved cholesterol testing will be needed. Such testing is the subject of a companion report by the program's Laboratory Standardization Panel.

According to the newly issued report, adults over age 20 should be tested every five years. If they fall into the borderline range but do not have coronary heart disease or two other risk factors, such as cigarette smoking, hypertension, diabetes, a family history of premature coronary heart disease or being male, they should receive dietary information and be retested a year later.

If, however, they do have coronary heart disease or two other risk factors or if they are in the high cholesterol range, their LDL-cholesterol level, which is the more specific and more causally connected risk factor in coronary heart disease than the overall level, should be tested.

Those with LDL levels of 160 mg/dl and above are considered high risk and require treatment. In addition, those with LDL levels between 130 and 159 mg/dl and with coronary heart disease or two other risk factors require treatment, which includes a two-step dietary program. Drugs are a last resort.

According to a 1986 NHLBI survey, half the physicians did not use dietary therapy until cholesterol levels were above 240 mg/ dl, and about 25 percent waited until 260 mg/dl and above.

"Many of these physicians were deterred from more actively using dietary therapy by their not having available practical guidance about to how to go about it,' Cleeman says.

The survey also showed that more than 75 percent of physicians did not prescribe drug therapy with patients who had cholesterol levels of 260 mg/dl, and more than one-third never prescribed drug therapy.

While the panel's report recommends more cholesterol testing, a problem exists: Accurate results are not always reported. About 47 percent of the laboratories in a 1985 College of American Pathologists Comprehensive Chemistry Survey did not fall within 5 percent of actual readings, says Herbert Naito, the Laboratory Standardization Panel chairman.

The companion report recommends a maximum 5 percent accuracy range initially and a maximum 3 percent range within five years. This will be accomplished, Naito says, when cholesterol-detector manufacturers supply laboratories with calibration materials from the federal Centers for Disease Control. Previously, many manufacturers had supplied inaccurate calibration samples.

The panel must next examine the accuracy of LDL-cholesterol readings, Naito says.

According to the 1986 NHLBI survey, fewer than half of U.S. adults had ever had their cholesterol checked and only 10 percent knew their cholesterol level.

Although the association between coronary heart disease and high cholesterol has been known for many years, it was not until 1984 that research showed that lowering cholesterol reduced the number of heart attacks and heart-attacks deaths.