Epicardial adipose tissue signatures in Asian coronary artery disease: Insights from cardiac CT

We aim to compare cardiac CT characteristics of epicardial adipose tissue (EAT), coronary plaque, and perivascular adipose tissue (PVAT) among East, South and Southeast Asian coronary artery disease (CAD) patients. This retrospective, cross-sectional study analyzed data from 2702 stable CAD patients, including 2078 East (56.4 ± 11.2 years, 59.5% male), 310 South (53.2 ± 10.4 years, 62.4% male), and 314 Southeast Asian (52.9 ± 11.2 years, 60.6% male) patients. From this clinical cohort, available imaging subsets were analyzed: 1090 patients with analyzable non-contrast computed tomography for EAT assessment and 751 patients with coronary computed tomography angiography for plaque and PVAT characterization. Compared to East Asian patients, South Asian patients exhibited higher EAT attenuation and high-density EAT volume ratio but lower EAT volume (difference: +1.45HU, 95% CI [0.05, 2.84], p = 0.042; +2.79% [0.76, 4.83], p = 0.007; -33.54cm 3 [-41.79, -25.29], p < 0.001). No significant differences were found in plaque volumes or compositions and PVAT mean attenuation across the three groups ( p > 0.05). Despite higher diabetes prevalence and family history of CAD in South Asian patients, these factors were not independently associated with EAT differences. In a multi-ethnic Asian cohort of stable CAD patients, South Asians showed a distinct pro-inflammatory EAT profile, including higher EAT attenuation and high-density volume ratio, independent of traditional risk factors, despite having similar coronary plaque burden, composition, and PVAT characteristics as other Asian groups. This finding suggests that ethnic-specific cardiovascular pathophysiology may operate through mechanisms beyond traditional cardiovascular risk factors.