Apolipoprotein B discordance with low-density lipoprotein cholesterol and non–high-density lipoprotein cholesterol in relation to coronary artery calcification in the Multi-Ethnic Study of Atherosclerosis (MESA)

Background: Discordant levels of apolipoprotein B (apo B) relative to low-density lipoprotein cholesterol (LDL-C) or non–high-density lipoprotein cholesterol (non-HDL-C) may be associated with subclinical atherosclerotic cardiovascular disease (ASCVD). Objective: The present study investigated whether discordance between apo B and LDL-C or non-HDL-C levels was associated with subclinical ASCVD measured by coronary artery calcium (CAC). Methods: This study was conducted in a subpopulation of the Multi-Ethnic Study of Atherosclerosis (MESA) cohort, aged 45 to 84 years, free of ASCVD, and not taking lipid-lowering medications at the baseline (2000–2002) (prevalence analytic N = 4623; incidence analytic N = 2216; progression analytic N = 3947). Apo B discordance relative to LDL-C and non-HDL-C was defined using residuals and percentile rankings (>5/10/15 percentile). Associations with prevalent and incident CAC (CAC > 0 vs CAC = 0) were assessed using prevalence ratio/relative risk regression and CAC progression (absolute increase/year) using multinomial logistic regression. Results: Higher apo B levels were associated with CAC prevalence, incidence, and progression. Apo B discordance relative to LDL-C or non-HDL-C was inconsistently associated with CAC prevalence and progression. Discordantly high apo B relative to LDL-C and non-HDL-C was associated with CAC progression. Associations for apo B discordance with non-HDL-C remained after further adjustment for metabolic syndrome components. Conclusion: Apo B was associated with CAC among adults aged ≥45 years not taking statins, but provided only modest additional predictive value of apo B for CAC prevalence, incidence, or progression beyond LDL-C or non-HDL-C. Apo B discordance may still be important for ASCVD risk assessment and further research is needed to confirm findings.