Impact of Novel LDL-C Assessment on the Utility of Secondary Non-HDL-C and ApoB Targets in Selected Worldwide Dyslipidemia Guidelines
Background—Selected dyslipidemia guidelines recommend non-high-density lipoprotein-cholesterol (non-HDL-C) and apolipoprotein B (apoB) as secondary targets to the primary target of low-density lipoprotein-cholesterol (LDL-C). We examined, after considering two LDL-C estimates that differ in accuracy: (1) how frequently non-HDL-C guideline targets could change management; and (2) utility of apoB targets after meeting LDL-C and non-HDL-C targets.
Methods—We analyzed 2,518 adults representative of the U.S. population from the 2011-2012 National Health and Nutrition Examination Survey and 126,092 patients from the Very Large Database of Lipids study with apoB. We identified all individuals as well as those with high-risk clinical features including coronary disease, diabetes, and metabolic syndrome who met very high- and high-risk guideline targets of LDL-C<70 and <100 mg/dL, using Friedewald estimation (LDL-CF) and a novel, more accurate method (LDL-CN). Next, we examined those not meeting non-HDL-C (<100, <130 mg/dL) and apoB (<80, <100 mg/dL) guideline targets. In those meeting dual LDL-C and non-HDL-C targets (<70 and <100 mg/dL, respectively, or <100 and <130 mg/dL respectively), we determined the proportion of individuals who did not meet guideline apoB targets (<80 or <100 mg/dL).
Results—A total of 7-9% and 31-36% of individuals had LDL-C<70 and <100 mg/dL, respectively. Among those with LDL-CF<70 mg/dL, 14-15% had non-HDL-C≥100 mg/dL, and 7-8% had apoB≥80 mg/dL. Among those with LDL-CF<100 mg/dL, 8-10% had non-HDL-C≥130 mg/dL and 2-3% had apoB≥100 mg/dL. In comparison, among those with LDL-CN<70 or 100 mg/dL, only ~2% and ~1% of individuals, respectively, had non-HDL-C and apoB values above guideline targets. Similar trends were upheld among those with high-risk clinical features: ~0-3% of individuals with LDL-CN<70 mg/dL had non-HDL-C≥100 mg/dL or apoB≥80 mg/dL compared to 13-38% and 9-25%, respectively, in those with LDL-CF<70 mg/dL. With LDL-CF or LDL-CN<70 mg/dL and non-HDL-C<100 mg/dL, 0-1% had apoB≥80 mg/dL. Among all dual LDL-CF or LDL-CN<100 mg/dL and non-HDL-C<130 mg/dL individuals, 0-0.4% had apoB≥100 mg/dL. The above findings were robust to sex, fasting status, and lipid-lowering therapy status.
Conclusions—After more accurately estimating LDL-C, guideline-suggested non-HDL-C targets could alter management in only a small fraction of individuals, including those with coronary disease and other high-risk clinical features. Furthermore, current guideline-suggested apoB targets provide modest utility after meeting cholesterol targets.
Clinical Trial Registration—URL: https://clinicaltrials.gov Unique Identifier: NCT01698489
- Received October 26, 2017.
- Revision received February 16, 2018.
- Accepted February 21, 2018.