Coronary Plaque Burden in South Asian Adults: Insights From the DILWALE Registry.

BACKGROUND: South Asian (SA) adults have disproportionately high rates of premature coronary artery disease, yet conventional risk calculators may not fully capture coronary plaque burden. OBJECTIVES: We analyzed the DILWALE (DIL Wellness and Arterial Health Longitudinal Evaluation) registry to quantify coronary plaque burden using computed tomography angiography (CTA) and compare it across risk categories using the 10-year atherosclerotic cardiovascular disease (ASCVD) risk calculator and American Heart Association PREVENT-ASCVD Calculator. METHODS: The DILWALE study is a medical record-based multicenter registry of SA adults (≥18 years) within Baylor Scott & White Health system. Patients who underwent clinically indicated coronary CTA were included and were risk stratified based on the PREVENT-ASCVD and Pooled Cohort Equations (PCE) risk scores. Quantitative plaque analysis was done using HeartFlow's plaque analysis tool to evaluate the association among PCE, PREVENT, and plaque burden. RESULTS: A total of 341 SAs were included. Among individuals stratified by the PREVENT score, median total plaque volume rose from 0 mm3 in the low-risk group (<5% 10-year predicted ASCVD risk) to 34 mm3, 161 mm3, and 161 mm3 in the borderline- (5%-7.4%), intermediate- (7.5%-19.9%), and high-risk (≥20%) groups, respectively (P < 0.0001). In the PCE cohort, median total plaque volume increased from 1 mm3 in the low-risk group to 91 mm3, 122 mm3, and 215 mm3 in the borderline-, intermediate-, and high-risk groups, respectively (P < 0.0001). CONCLUSIONS: In this SA cohort, higher PREVENT and ASCVD/PCE risk categories were associated with higher plaque burden. CTA reveals substantial noncalcified plaque missed by calcium scoring, underscoring its value for anatomic risk in SA adults.