Patient-Level Discordance in Population Percentiles of the TC/HDL-C Ratio Compared with LDL-C and Non-HDL-C: The Very Large Database of Lipids Study (VLDL-2B)
Background—The total cholesterol to high-density lipoprotein cholesterol (TC/HDL-C) ratio, estimated low-density lipoprotein cholesterol (LDL-C), and non-HDL-C are routinely available from the standard lipid profile. We aimed to assess the extent of patient-level discordance of TC/HDL-C with LDL-C and non-HDL-C because discordance suggests the possibility of additional information.
Methods and Results—We compared population percentiles of TC/HDL-C, Friedewald-estimated LDL-C, and non-HDL-C in 1,310,432 U.S. adults from the Very Large Database of Lipids. Lipid testing was performed by ultracentrifugation (VAP, Atherotech, AL). One in three patients had ≥25 percentile units discordance between TC/HDL-C and LDL-C while one in four had ≥25 percentile units discordance between TC/HDL-C and non-HDL-C. The proportion of patients with TC/HDL-C > LDL-C by ≥25 percentile units increased from 3% at triglycerides <100 mg/dL to 51% at triglycerides 200-399 mg/dL. On a smaller scale, TC/HDL-C > non-HDL-C discordance by ≥25 percentile units increased from 6% to 21%. In those with <15th percentile levels of LDL-C (<70 mg/dL) or non-HDL-C (<93 mg/dL), a respective 58% and 46% were above the percentile-equivalent TC/HDL-C of 2.6. Age, sex, and directly measured components of the standard lipid profile explained >86% of the variance in percentile discordance between TC/HDL-C vs. LDL-C and non-HDL-C.
Conclusions—In this contemporary, cross-sectional, big data analysis of U.S. adults who underwent advanced lipid testing, the extent of patient-level discordance suggests that TC/HDL-C may offer potential additional information to LDL-C and non-HDL-C. Future studies are required to determine the clinical implications of this observation.
Clinical Trial Registration Information—www.clinicaltrials.gov. Identifier: NCT01698489.
- Received February 26, 2015.
- Revision received May 21, 2015.
- Accepted June 18, 2015.