Objectives: This study sought to determine whether epicardial adipose tissue (EAT) volume predicts the progression of coronary artery calcification (CAC) score in the general population.
Background: EAT predicts coronary events and is suggested to influence the development of atherosclerosis.
Methods: We included 3,367 subjects (mean age 59 8 years; 47% male) from the population-based Heinz Nixdorf Recall study without known coronary artery disease at baseline. CAC was quantified from noncontrast cardiac electron beam computed tomography at baseline and after 5 years. EAT was defined as fat volume inside the pericardial sac and was quantified from axial computed tomography images. Association of EAT volume with CAC progression (log[CAC(follow-up) + 1] - log[CAC(baseline) + 1]) was depicted as percent progression of CAC + 1 per SD of EAT.
Results: Subjects with progression of CAC above the median had higher EAT volume than subjects with less CAC change (101.1 ± 47.1 ml vs. 84.4 43.4 ml; p < 0.0001). In regression analysis, 6.3% (95% confidence interval [CI]:2.3% to 10.4%; p = 0.0019) of progression of CAC + 1 was attributable to 1 SD of EAT, which persisted after adjustment for risk factors (6.1% [95% CI: 1.2% to 11.2%]; p ¼ 0.014). For subjects with a CAC score of >0 to ≤100, progression of CAC þ 1 by 20% (95% CI: 11% to 31%; p < 0.0001) was attributable to 1 SD of EAT. Effect sizes decreased with CAC at baseline, with no relevant link for subjects with a CAC score ≤400 (0.2% [95% CI: -3.5% to 4.2%]; p = 0.9). Likewise, subjects age <55 years at baseline showed the strongest association of EAT with CAC progression (20.6% [95% CI: 9.7% to 32.5%]; p < 0.0001). Interestingly, the effect of EAT on CAC progression was more pronounced in subjects with low body mass index (BMI), and decreased with degree of adiposity (BMI ≤25 kg/m(2):19.8% [95% CI: 9.2% to 31.4%]; p = 0.0001, BMI >40 kg/m(2): 0.8% [95% CI: -26.7% to 38.9%]; p = 0.96).
Conclusions: EAT is associated with the progression of CAC, especially in young subjects and subjects with low CAC score, suggesting that EAT may promote early atherosclerosis development.