Relationship between epicardial adipose tissue thickness and coronary calcification in patients with stable coronary artery disease on chronic statin therapy

Introduction While increased epicardial adipose tissue thickness (EATT) is a known predictor of coronary calcification severity, data on its relationship with specific plaque characteristics like volume and density are scarce. Furthermore, the modifying effect of statin therapy on these associations remains unclear. Objective To assess the relationship between coronary calcium volume and density, derived from cardiac computed tomography, and epicardial adipose tissue thickness, depending on long-term use of HMG-CoA reductase inhibitors. Methods The study included 75 individuals with stable coronary artery disease (CAD) and a coronary artery calcium score (CACS) of ≥ 0. The median age was 62 (57.0; 68.0) years, with 44 (59%) being male. Forty participants (53.3%) who had been taking statins regularly for at least one year prior to inclusion were assigned to Group 1. Group 2 (n=35, 46.7%) consisted of individuals who had never taken statins. Quantitative assessment of coronary calcium (CC) volume and density, as well as the calculation of the Agatston score, was performed using cardiac computed tomography on a 640-slice CANON scanner with multimodality workstation software. EATT was measured using multiplanar reconstruction along the left ventricle's short axis, at the mid-ventricular level, at the midpoint of the right ventricle's free wall. Results In the overall group, the median Agatston score was 170 [57; 275]. The median calcium volume was 152 [41; 211] mm³, the median density was 49 [21; 103] HU, and the median EATT was 17 [12; 25] mm. The groups were comparable in terms of main clinical and anthropometric parameters and EATT values. However, they differed significantly in Agatston score (Group 1: 202 [84; 338] vs. Group 2: 157 [43; 231], p= 0.01), CC volume (Group 1: 146 [35; 195] mm³ vs. Group 2: 161 [50; 223] mm³, p=0.007), and CC density (Group 1: 61 [29; 120] HU vs. Group 2: 38 [12; 93] HU, p= 0.005). Correlation analysis revealed that EATT was positively correlated with the Agatston score, with a stronger association in Group 2 (r= 0.39, p= 0.03 in Group 1 vs. r= 0.47, p= 0.01 in Group 2). Furthermore, in Group 2, EATT showed a positive correlation with CC volume (r= 0.62, p= 0.001) and a negative correlation with CC density (r= -0.36, p= 0.009). No significant correlations between these parameters were found in Group 1. Conclusions In patients with stable CAD, EATT is positively correlated with the Agatston score, with a stronger association observed in statin-naïve patients. Furthermore, in the absence of statin therapy, EATT is positively associated with CC volume and negatively associated with its density. This may suggest a modifying role of HMG-CoA reductase inhibitors in the relationship between epicardial adiposity and the characteristics of coronary calcium.