Non-HDL cholesterol may be best marker of cardiovascular risk in statin-treated patients

Non-high-density lipoprotein cholesterol (non-HDL-C) may be a better marker of cardiovascular risk in patients taking statins than low-density lipoprotein cholesterol (LDL-C) or apolipoprotein B (apoB), according to a new study.

Researchers performed a meta-analysis of individual patient data from eight randomized, controlled trials of statin therapy that measured lipid and apolipoprotein levels in all participants at baseline and at one year. The goal of the study was to determine the association between non-HDL-C, LDL-C, and apoB and cardiovascular risk in statin-treated patients.

Studies were identified by a search of the literature through Dec. 31, 2011. The researchers determined hazard ratios (HRs) for risk of major cardiovascular events according to each 1-SD increase in LDL-C, non-HDL-C and apoB levels, with adjustment for established risk factors. Results appeared in the March 28 Journal of the American Medical Association.

Of 62,154 patients, 38,153 were assigned to receive statin therapy and had lipid and apolipoprotein levels available at baseline and at one year. Among this group, 158 had fatal myocardial infarctions, 1,678 had nonfatal myocardial infarctions, 615 had other fatal coronary artery disease events, 2,806 were hospitalized for unstable angina, and 1,029 had fatal or nonfatal strokes during follow-up.

Adjusted HRs for major cardiovascular events were 1.13 per 1-SD increase in LDL-C, 1.16 per 1-SD increase in non-HDL-C, and 1.14 per 1-SD increase in apoB. The HR for non-HDL-C was significantly higher than those for LDL-C (P=0.002) and apoB (P=0.02), but the HRs for LDL-C and apoB did not significantly differ (P=0.21) from one another.

The authors acknowledged that the eight trials had used different inclusion criteria and that the results may not apply to patients in clinical practice, among other limitations. However, they concluded that although three of the studied markers have a strong association with cardiovascular events, non-HDL-C's association appears to be the strongest.

“Given the fact that many other arguments for the clinical applicability of non–HDL-C and LDL-C are identical, non-HDL-C may be a more appropriate target for statin therapy than LDL-C,” the authors wrote.