Correlation Between Pancreatic Fat Quantification By Dual-layer Spectral Detector CT And Coronary Artery High-risk Plaque In Patients With Type 2 Diabetes

Objective:With the increasing prevalence of type 2 diabetes（T2DM）,preventing and delaying the occurrence and development of coronary artery disease（CAD）in patients with type 2 diabetes has become a public health issue of increasing concern.The existence of high-risk plaques helps to predict the occurrence of subsequent cardiovascular events,and ectopic fat deposition has been proved to be a risk factor for cardiovascular disease.At present,there is a lack of research on the effect of pancreatic fat deposition on coronary atherosclerosis.Therefore,this study explored the relationship between pancreatic fat deposition and coronary artery high-risk plaques in patients with type 2 diabetes,in order to explore appropriate imaging markers to predict the occurrence of cardiovascular events in patients with diabetes.Methods:Patients with T2DM who underwent coronary artery CT angiography with double-layer detector spectral CT because of chest pain from October 2021 to October2022 were divided into non-plaque group and non-high-risk plaque group according to the presence of coronary artery plaque.The fat content of pancreas was measured on CT conventional mixed level image,CT_{40ke V}single level image,CT_{70ke V}single level image,effective atomic number map and iodine map(recorded as CT_poly,CT_{40ke V},CT_{70ke V,}Z_effand iodine intake).The slope of energy spectrum curveλ_HUwas calculated by formula.The correlation between pancreatic energy spectrum attenuation index and coronary artery high risk plaque was analyzed by SPSS software.In order to analyze the relationship between pancreatic fat deposition and coronary artery high risk plaque in patients with T2DM,the most sensitive pancreatic energy spectrum attenuation index for identifying high risk plaque was selected by drawing ROC curve and calculating AUC,and the best cut off value of pancreatic energy spectrum index for high risk plaque was obtained.the data lower than the optimal cut off value of pancreatic energy spectrum index was defined as pancreatic fat deposition.Independent risk factors of high-risk plaque in patients with T2DM were screened by Logistic regression,and the relationship between high-risk plaque and pancreatic fat deposition was analyzed.Results:A total of 135 patients were divided into non-plaque group（n=42）,non-high-risk plaque group（n=48）and high-risk plaque group（n=45）.The age of patients in high-risk plaque group and non-high-risk plaque group was older than that in non-plaque group,and the levels of high-density lipoprotein and apolipoprotein An in non-plaque group were significantly higher than those in high-risk plaque group and non-high-risk plaque group.In addition,compared with the non-high-risk plaque group,there were more patients with severe stenosis,SIS and SSS in the high-risk plaque group were lower than those in the non-high-risk plaque group,and the difference was not statistically significant.The energy spectrum indexes of pancreas in high-risk plaque group were lower than those in non-high-risk plaque group and non-plaque group,and after adjusting for risk factors such as age,sex,BMI and biochemical indexes,low Zeff level was still independently correlated with coronary artery high-risk plaque（OR=6.363,95%CI=2.420-14.726,P<0.001）.Conclusion:In patients with T2DM,the attenuation index of pancreatic energy spectrum is correlated with coronary artery plaque,especially with the occurrence of high-risk plaque.Low level of Zeff is an independent risk factor for coronary high-risk plaque,indicating that pancreatic fat deposition may increase the risk of coronary artery high-risk plaque in patients with T2DM.