Comparison of coronary atherosclerotic plaque progression in East Asians and Caucasians by serial coronary computed tomographic angiography: A PARADIGM substudy.

OBJECTIVES To investigate potential differences in plaque progression (PP) between in East Asians and Caucasians as well as to determine clinical predictors of PP in East Asians. BACKGROUND Studies have demonstrated differences in cardiovascular risk factors as well as plaque burden and progression across different ethnic groups. METHODS The study comprised 955 East Asians (age 60.4 ​± ​9.3 years, 50.9% males) and 279 Caucasians (age 60.4 ​± ​8.6 years, 74.5% males) who underwent two serial coronary computed tomography angiography (CCTA) studies over a period of at least 24 months. Patients were enrolled and analyzed from the PARADIGM (Progression of AtheRosclerotic PlAque DetermIned by Computed TomoGraphic Angiography IMaging) registry. After propensity-score matching, plaque composition and progression were compared between East Asian and Caucasian patients. Within East Asians, the plaque progression group (defined as plaque volume at follow-up CCTA minus plaque volume at baseline CCTA> 0) was compared to the no PP group to determine clinical predictors for PP in East Asians. RESULTS In the matched cohort, baseline volumes of total plaque as well as all plaque subtypes were comparable. There was a trend towards increased annualized plaque progression among East Asians compared to Caucasians (18.3 ​± ​24.7 ​mm3/year vs 16.6 ​mm3/year, p ​= ​0.054). Among East Asians, 736 (77%) had PP. East Asians with PP had more clinical risk factors and higher plaque burden at baseline (normalized total plaque volume of144.9 ​± ​233.3 ​mm3 vs 36.6 ​± ​84.2 ​mm3 for PP and no PP, respectively, p ​< ​0.001). Multivariate logistic regression analysis showed that baseline normalized plaque volume (OR: 1.10, CI: 1.10-1.30, p ​< ​0.001), age (OR: 1.02, CI: 1.00-1.04, p ​= ​0.023) and body mass index (OR: 2.24, CI: 1.01-1.13, p ​= ​0.024) were all predictors of PP in East Asians. Clinical events, driven mainly by percutaneous coronary intervention, were higher among the PP group with a total of 124 (16.8%) events compared to 22 (10.0%) in the no PP group (p ​= ​0.014). CONCLUSION East Asians and Caucasians had comparable plaque composition and progression. Among East Asians, the PP group had a higher baseline plaque burden which was associated with greater PP and increased clinical events.