Noninvasive Methods For Assessment Of Calcification And The Related Risk Factors In Maintenance Hemodialysis Patients

Object: Use different methods to assess the vascular and valvecalcification in maintenance hemodialysis patients. Analyze their respectiverisk factors and find the best alternative methods to predict coronary CTcoronary calcification, in order to help clinicians to make therapeuticdecisions.Methods: A total of117maintenance hemodialysis patients wereenrolled at the Sichuan Provincial People’s Hospital. MSCT was taken todetect and quantify coronary artery; two radiologists to evaluate the presenceof VC evaluated radiographs of the abdomen, pelvis and hands;echocardiography was used to detect the valve calcification and PWV wasused to evaluate the arterial stiffness. Pulse pressures were measured.Pre-dialysis measurements including white blood cell count, hemoglobin,platelet count, BUN, creatinine, albumin,C-reactive protein,total cholesterol,triglyceride, calcium, phosphorus, intact parathormone, ferritin and25-(OH)vitamin D, Tryptophan, kynurenine were measured. Differences in the meanand median values between groups were evaluated using the independentt-test and the Mann–Whitney U test, respectively. ROC curve was used toanalyze the ability of different method to predict coronary calcification.Results:1. The mean CACs of the total117patient was366.03(range:0-4251.4). Forty-six patients CACs=0（39.3%）,thirty-one patients0＜CACs≤100(26.5%), fifteen patients100＜CACs≤400(12.8%), and fifteenpatients400＜CACs(21.4%). Left anterior descending artery (48.7%) and right coronary artery (41.0%) were easier to get calcified.2. X-ray examination detected eighty-nine patients(76.1%) had vascularcalcification （VC>0）, thirty-nine patients(33.4%) had mild vascularcalcification(0<VC≤3), fifty patients(56.2%) had moderate to severe vascularcalcification(VC>3). Abdominal aortic calcification rate is67.52%, iliac andfemoral artery calcification rate is55.56percent, hands and fingers radialartery calcification rate is15.38%.3.3. Cardiac valve calcification was found in41patients (35.04%),21patients (17.9%) among them were found aortic valve calcification(MVC) and28patents (23.9%) had mitral valve calcification; both aortic and mitral valvewere detected calcified in8patients (6.8%).4. Logistic regression analysis demonstrate that the presence of coronaryartery calcification was correlated with age, dialysis vintage, pulse pressure,serum phosphate, LDL-C, Alb, IL-6; the risk factors of local vascularcalcification detected by X-rays included with age, dialysis duration, pulsepressure, serum phosphate, Hb, LDL-C,TC, IL-6;and valve calcification isrelated to age, dialysis duration and pulse pressure. Interestingly the IL-6isassociated with all the arteries except for the radial and the digital artery.5.25-(OH)D and inflammation marker Tryptophan, Kynurenine showedno correlation with vascular calcification and arterial stiffness.6. Prediction of coronary artery calcification were compared withROC.The AUC of total X-rays,valve calcification, abdominal aortic, pelvisX-ray, pelvis and hands together for CACs>0was0.771,0.765,0.711,0.710respectively, others are smaller than0.6.When predict for CACs>100, AUC ofvalve calcification, pelvis arteris, pelvis together with hands X-ray, totalX-rays and Iliac artery are0.747,0.735,0.722,0.722,0.714, respectively. Otehers are less than0.7; Predict for CACs>400, AUC of lilac artery togetherwith femoral artery, the entire X-rays and lilac artery are0.719,0.708,0.701,respectively. Others’ AUC are less than0.7.7. The AUC of PWV and PP when predicting CACs>0are PWVL0.691, PWVR0.657, PP0.679, ABIL0.418, ABIR0.446, respectively. In theprediction of CACs>100and CACs>400, PP has the largest area with0.679,0.696while others are no more than0.65.Conclusion:1. Vascular calcification is common in MHD patients. Leftanterior descending coronary artery(LAD) is most likely to be involved in theCoronary calcification. The incidence of calcification in the abdominal aortais higher than other peripheral vascular whereas the radial and the digitalartery have a lower chance to calcify.2. Age, Dialysis vintage, PP are the indepengdent risk factors of vascularcalcification. Hyperphosphatemia, abnormal lipid metabolism, malnutritionand inflammation are associated with vascular calcification.3. We reconmmend to use pelvis X rays to predict the prognosis of MHDpatients; And The pulse pressure(PP) is a potential method to predict coronaryartery calcification in hemodialysis patients which could be used as a aimplepreliminary assessment tool.