Cholesterol Levels Getting Better in U.S.

Nov. 17, 2009 -- Researchers say the prevalence of high levels of LDL "bad" cholesterol decreased dramatically among U.S. adults between 1999 and 2006.

That's the good news from a study published in the Nov. 18 issue of The Journal of the American Medical Association.

The bad news -- or part of it -- is that a large percentage of adults are still not being screened or treated for high cholesterol, which is a major risk factor for heart disease.

Fewer Have High LDL Cholesterol

A team of scientists led by Elena V. Kuklina, MD, PhD, of the CDC analyzed data from the National Health and Nutrition Examination Survey (NHANES), a program of studies designed to assess the health and nutritional status of large numbers of people in the U.S.

They restricted their study sample to 7,044 people after excluding pregnant women and people for whom data were missing.

They found that overall, prevalence for high LDL decreased from 31.5% in 1999-2000 to 21.2% in 2005-2006.

However, among those who tested high for LDL during the study:

• 35.5% had not been screened for LDL in the past.
• 24.9% who had been screened previously were unaware they had high LDL levels.
• 39.6% were untreated or not treated adequately in 2005-2006.

The American College of Cardiology's immediate past president, W. Douglas Weaver, MD, issued a comment about the study's findings. "I find these results alarming. Although we are making great strides in cholesterol management in patients with known heart disease, this study shows that many patients who could benefit from lipid-lowering medications and changes in their lifestyle and diet are still going unrecognized, and untreated."

Screening for Cholesterol Remains Steady

While the prevalence for high LDL levels decreased to 21.2% in the latest two-year period studied, it varied substantially by patient risk category, the researchers say. The highest prevalence of elevated LDL was observed in the high-risk category, which included people with self-reported heart disease, angina, heart attack, stroke, and diabetes, plus others with high blood glucose levels while fasting, the report says.

The self-reported use of cholesterol-lowering drugs increased from 8% to 13.4%, but screening rates didn't change significantly, remaining at less than 70% during all four of the two-year study periods. This could be due to a lack of consensus on when screening for high cholesterol should start, the researchers say.

Confusion over the definition of high-risk levels and communication problems between doctors and patients may also cause many people to miss the chance to improve their LDL counts, the researchers conclude.