UCSF

Objectives

The 2018 and 2019 U.S. guidelines for the management of cholesterol and primary prevention of atherosclerotic cardiovascular disease (ASCVD) recommend consideration of cardiovascular risk-enhancing factors (REFs), including South Asian ancestry, to refine ASCVD risk estimation. However, the associations of REFs with atherosclerosis are unclear in South Asian American adults, who have a disproportionately elevated premature coronary heart disease risk. In the Mediators of Atherosclerosis in South Asians Living in America (MASALA) cohort, we investigated associations of individual REFs, or the number of REFs, with coronary artery calcium (CAC).

Methods

Using baseline and follow-up data from MASALA, we evaluated the association of REFs (family history of ASCVD, low-density lipoprotein cholesterol ≥160 mg/dL, triglycerides ≥175 mg/dL, lipoprotein(a) >50 mg/dL, high-sensitivity C-reactive protein [hsCRP] ≥2.0 mg/dL, ankle-brachial index <0.9, chronic kidney disease, metabolic syndrome), individually and combined, with baseline prevalent CAC, any CAC progression (including incident CAC and CAC progression), and annual CAC progression rates using multivariable logistic regression and generalized linear models.

Results

Among 866 adults, mean age was 55 [SD 9] years and 47% were female. There were no significant associations of REFs with baseline prevalent CAC or any CAC progression (incident CAC and CAC progression at Exam 2) after adjustment. Among the 56% of participants who had any CAC progression, having 3+ REFs was associated with a significantly higher annual CAC progression rate (adjusted rate ratio [aRR] 1.94, 95% CI 1.39-2.72) vs. having 0 REFs. The annual CAC progression rate was 20% higher per additional REF (aRR 1.20, 95% CI 1.09-1.32). Findings were similar after excluding statin users, and among those with low 10-year ASCVD risk (<5%).

Conclusions

Among South Asian American adults, we found no association of REFs with prevalent CAC at baseline or having any CAC progression. Among those with any CAC progression, a higher number of REFs was associated with higher annual CAC progression rates.