Abstract 496: Elevated Volumes of Pericardial Fat, Inflammation, Hypoadiponectinemia and a Noncalcified Coronary Plaque Phenotype Are Characteristics of Lean Patients With Coronary Artery Disease and May Explain the Obesity Paradox
Recent data indicates that obese patients with coronary artery disease have a favourable prognosis compared to lean patients. So far the pathophysiologic background for this so called ,, obesity paradox“ is not well understood. Pericardial fat is a strong risk factor for coronary artery disease by contributing to hypodiponectinemia and inflammation. We hypothesize that lean patients with coronary artery disease reveal elevated pericardial fat volumes, low adiponectin and high inflammatory marker levels and a different coronary plaque phenotype. For that purpose we investigated 280 (174 male, age 59+-8 years) patients with suspected coronary artery disease by Dual Source CT-coronary angiography which allows to assess coronary plaque burden, plaque composition and pericardial fat volume simultaneously. Patients were categorized in 4 groups: Group1: BMI 25 and detectable coronary atherosclerosis, Group III: BMI 25 and no coronary atherosclerosis. Serum levels of Adipoenctin, hs CRP, IL 6, TNF-alpha, volumes of pericardial fat, coronary plaque score and coronary plaque composition were compared among the different groups. Overall n = 42 patients qualified for group I (mean BMI = 23.8), n = 80 for group II (mean BMI = 28.9), n = 88 for group III (mean BMI = 23.6) and n = 70 for Group IV (mean BMI = 27,8). The volume of pericardial fat was significantly higher in group I (213cc ± 44) compared to Group III (112 cc ± 32) and Group IV (178 cc ± 54, p < 0.05) but not different to group II (231cc ±43, p = 0.08). In group I the lowest adiponectin levels and the highest hs-CRP levels were obeserved compared to all other groups (p <0.05). The number of coronary plaques was similar in Group I and II (8.6 vs. 9.1, p = 0.09) with a significantly higher number of noncalcified and mixed plaques in Group I (1.7 and 5.3 vs 0.7 and 4.1 respectively, p < 0.05). The results of our study demonstrate that lean patients with coronary artery disease reveal lower levels of adiponectin, higher hsCRP levels and more noncalcified and mixed plaques and similar volumes of pericardial visceral fat compared to obese patients with coronary artery disease. The current observations may be an explanation for the poorer prognosis of lean CAD-patients demonstrated in recent trials and may influence patient management in future.