The impact of obesity on subclinical coronary atherosclerosis according to the risk of cardiovascular disease

Objective To evaluate whether the association of obesity with coronary atherosclerosis depends on the risk of cardiovascular disease (CVD). Methods A total of 1,406 asymptomatic Korean adults underwent both cardiac and abdominal multislice computed tomography (MSCT) as part of a routine health check-up. Obesity was measured using body mass index (BMI), waist circumference (WC), and MSCT-derived area/ratio of visceral and subcutaneous fat. The burden of CVD risk was assessed by the Framingham risk equation. Results In the low-risk group for CVD, obesity measurements (standardized odds ratio, 95% confidence interval) of BMI (1.406, 1.197-1.652), WC (1.707, 1.434-2.032), visceral fat area (1.700, 1.438-2.009), and visceral-to-subcutaneous fat ratio (1.620, 1.379-1.903) were associated with the presence of coronary calcification after adjusting for traditional CVD risks. But in the moderate-to-high risk group, the associations were attenuated. For additional adjustments of obesity measurements, in the low-risk group, WC (1.717, 1.172-2.514) and visceral-to-subcutaneous fat ratio (1.400, 1.029-1.904) were independent determinants of coronary calcification. Conclusions Obesity is differentially associated with subclinical coronary atherosclerosis, according to the burden of CVD risk. In low-risk adults, the relative distribution of abdominal fat, as well as whole body fat, is important to coronary atherosclerosis.