Cholesterol and coronary heart disease: predicting risks in men by changes in levels and ratios.

BACKGROUND

Little is known about the relative ability of different measures of change in cholesterol to discriminate coronary heart disease risk. We evaluated this ability for changes in low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, LDL/HDL ratios, and total cholesterol/HDL ratios.

METHODS

We predicted risks of coronary heart disease using data from 3641 men in the Lipid Research Clinics Coronary Primary Prevention Trial. Treating these patients as a cohort, we estimated risks associated with changes in cholesterol levels independent of the patients' randomization group.

RESULTS

Changes in LDL and HDL cholesterol when used in combination were each significant predictors of coronary heart disease risk (odds ratios [OR] for 10% increases, 1.15 and 0.84, respectively; P < 0.001). Changes in LDL/HDL and total cholesterol/HDL ratios had similar discriminating ability (OR for 10% increases, 1.17 and 1.21, respectively; P < 0.0001). In the best discriminating models, changes in ratios added information about risks to changes in LDL cholesterol, although changes in LDL cholesterol levels failed to add information to changes in ratios.

CONCLUSIONS

Changes in total cholesterol/HDL and LDL/HDL ratios were better predictors of risk for coronary heart disease than were changes in LDL cholesterol levels alone. When assessed as percentage changes averaged during the first two months of intervention, they were among the best discriminators of risk. Clinicians selecting treatments for intervention should include among their considerations the treatment's effect on both LDL and HDL cholesterol rather than their effects on LDL cholesterol levels alone.