Clinical significance of zero coronary artery calcium in individuals with LDL cholesterol ≥190 mg/dL: The Multi-Ethnic Study of Atherosclerosis

Individuals with low-density lipoprotein cholesterol (LDL-C) ≥190 mg/dL are considered high-risk and current guidelines recommend initiating high-intensity statin therapy in this group. We sought to examine the predictive ability of zero CAC in this high-risk group. Multi-Ethnic Study of Atherosclerosis participants without clinical cardiovascular disease and baseline LDL-C ≥190 mg/dL were identified. Cardiovascular risk factors were compared between those with CAC = 0 and CAC >0. Multivariable Poisson regression was used to identify predictors of CAC = 0. Association of CAC = 0 with incident cardiovascular events over a median follow-up of 13.2 years was examined using multivariable-adjusted Cox regression. 246 individuals (mean age = 63 ± 9.4 years; 42% male; 31% white; 37% CAC = 0) with LDL-C ≥190 mg/dL were identified (mean LDL-C = 215 ± 27 mg/dL). Age 0 (incidence rate per 1000 person-years = 26.4; 10-year risk = 20%; risk/year = 2.0%), adjusted HR 0.25 (95%CI = 0.10–0.66). Among persons with LDL-C ≥190 mg/dL, younger age, female sex, and the absence of diabetes were associated with CAC = 0. CAC = 0 was associated with a low risk of cardiovascular events, suggesting the utility of CAC assessment for stratifying risk in this high-risk group. [Display omitted] •Asymptomatic individuals with LDL-C ≥190 mg/dL are considered high-risk for future cardiovascular events.•Distribution of risk factors in these individuals is heterogeneous and varies by the presence or absence of CAC.•In MESA participants with LDL-C ≥190 mg/dL, younger age, female sex, and lack of diabetes were associated with absence of CAC.•Absence of CAC was independently associated with better cardiovascular outcomes in this MESA sub-group.•Absence of CAC may help ‘de-risk’ individuals in this high-risk patient population.