Remnant cholesterol and associations with incidence, progression, and change in coronary artery calcium in South Asian Americans

BACKGROUND: Remnant cholesterol (RC) may contribute to residual risk of atherosclerotic cardiovascular disease (ASCVD), but few studies have examined this in South Asian populations, who experience a disproportionately high incidence of ASCVD. OBJECTIVE: Using data from the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study, a community-based longitudinal cohort of South Asian men and women without ASCVD at baseline, we examined the association between RC and change in coronary artery calcium (CAC). METHODS: Baseline fasting blood specimens and questionnaires were obtained between 2010-2013. CAC was assessed both at baseline and after 5-year follow-up in 698 participants. We used multivariable linear and logistic regression to examine relationships between RC quartile and CAC incidence (no CAC at baseline to any CAC at examination 2), CAC progression, and overall change in CAC. RESULTS: In 892 MASALA study participants at baseline, mean RC was 25.8 ± 11.8 mg/dL. Incident CAC occurred in 25.8% of participants and increased across RC quartiles (P = .002). After covariate adjustment, individuals with RC levels in the third (odds ratio [OR]: 2.24, 95% CI: 1.01-4.98) and fourth quartiles (OR: 2.57, 95% CI: 1.20-5.51) had significantly higher odds of incident CAC after 5 years than those in the lowest RC quartile. These associations persisted after sequential adjustment for behaviors, adiposity, and measures of insulin sensitivity and did not vary by gender. RC quartiles were not associated with CAC progression or CAC change. CONCLUSION: Higher RC levels were associated with increased odds of incident CAC independent of risk factors for ASCVD.