"Bad" Cholesterol May Not Be the Best Predictor of Heart Disease Risk in Generally Healthy Individuals
New Insights from Landmark Air Force/Texas Coronary Atherosclerosis Prevention Study (AFCAPS/TexCAPS) of Lovastatin (Mevacor)
Feb 7, 2000
New information published this week in Circulation: Journal of the American Heart Association, from the landmark AFCAPS/TexCAPS study of lovastatin (Mevacor), suggests that low-density lipoprotein cholesterol (LDL-C, the "bad" cholesterol) is not the best predictor of risk for a major coronary event in generally healthy persons with average LDL-C and below average high-density lipoprotein cholesterol (HDL-C, the "good" cholesterol) levels.
Rather, as presented by Antonio M. Gotto, Jr., MD, DPhil, Dean of the Weill Medical College of Cornell University, and co-authors, concentrations of the proteins apolipoprotein (apo) B and apo AI were better predictors, especially when combined to form the apo B/AI ratio. These apolipoproteins are major components of LDL and HDL, respectively, and may be more sensitive measures of risk than LDL and HDL themselves.
In those without pre-existing heart disease who have average to mildly elevated total cholesterol and LDL-C, and below average HDL-C, LDL-C was not predictive of a major heart disease event unless it was considered in conjunction with HDL-C. Therefore, HDL-C measurement should be an essential component of risk assessment in men and women with average to mildly elevated LDL-C, in accord with previously reported epidemiological studies, such as the Framingham Heart Study.
Even in this cohort with a mean LDL-C at baseline of 150 mg/dL (lower than the initiation level recommended by current guidelines for drug treatment), there is no evidence to indicate a level of LDL-C below which lowering LDL-C and increasing HDL-C is not of coronary benefit.
After one year of treatment with lovastatin (Mevacor), on-treatment apo AI, apo B, and the ratio of apo B to apo AI were the best predictors of subsequent major coronary events. These findings suggest that further consideration should be given to measuring apos B and AI in risk assessment and treatment evaluation, and to incorporating them into future guidelines and goals in the United States.