The Risk Factors Of Abdominal Aorta Calcification In Patients With CKD Stage 3 To 5 Not Undergoing Dialysis

Objective:To investigate the distribution and obtain risk factors of abdominal aorta calcification in patients with chronic kidney disease stages 3 to 5.Methodology:This was a cross-sectional observational study.In this research,Patients were selected from the department of Nephrology,Zhongda Hospital from 2014 to 2016 with chronic kidney disease stages 3 to 5.The aortic calcification area index(ACAI)was used to evaluate the abdominal aorta calcification through computed tomography(CT).During imaging,10 slices of the abdominal aorta were obtained at 1 cm intervals from the common iliac bifurcation.The area of each aortic cross-section and its corresponding calcification were measured separately using NIH Image software(NIH:National Institutes of Health,United State of America).A ratio of two area was then calculated and expressed in percentage for 10 different slices.Based on these ratios,the ACAI was taken as the mean value from 10 slices.Data analyses were processed using SPSS software(version 23.0).Logistic regression was conducted to assess the relation between abdominal aorta calcification(dependent variable)and independent variables(clinical and biological characteristics).Risk factors were expressed in(OR(95%CI);P)and values with P<0.05 were considered as statistically significant.Results:1.158 patients,including 56.3%male,were observed in this research with an average age of 58.18±12.16.The proportions of patients with CKD were 30.4%,29.1%%and 40.5%from stage 3 to 5 respectively.It is found that chronic glomerular disease and diabetic nephropathy were the main reason of CKD.Among all CKD patients,there are 82.9%having high blood pressure,46.8%having diabetes and 15.2%with coronary heart disease at the same time.In addition,patients taking phosphorus binders and activated Vitamin D accounted for 31%and 43.7%individually.2.The overall prevalence of abdominal aorta calcification(ACAI>0)for all patients was 57%(n=90).Interestingly,there is no significant difference observed from the prevalence of abdominal aorta calcification at stages 3 to 5.Besides,80%of the research group present a minor degree of calcification(ACAI<10).Patients with coronary heart disease or diabetes had higher ACAI than those without coronary heart disease or diabetes(P<0.05).3.After comparing the two groups of patients(with or without calcification),significant differences can be found in different aspects.These included patient's age,the percentage of having diabetes or coronary heart disease,serum albumin,triacylglyceride and ESR(P<0.05).According to the logistic regression analysis,it was generally shown that age(1.138(1.082,1.197);P<0.001),triacylglyceride(1.923(1.200,3.081);Pt=0.007)and ESR(1.015(1.001,1.030);P=0.015)were independent risk factors for abdominal aorta calcification,while serum Ca,phosphorus and iPTH were irrelvant.Furthermore considering the complexity of CKD inducement,its complications and individual difference of patients,the overall research group was divided into subgroups based on age,gender,causes of CKD and CKD stages.It was observed that independent risk factors obtained from subgroups were different from previous results.Conclusion:1.The prevalence of abdominal aorta calcification(ACAI>0)was 57%(n=90).The age of patients(1.138(1.082,1.197);P<0.001),triacylglyceride(1.923(1.200,3.081);P=0.007)and ESR(1.015(1.001,1.030);P=0.015)were independent risk factors for abdominal aorta calcification.2.The development of establishing specific criteria for CKD patients to predict and evaluate vascular calcification is still a challenge since various factors(e.g.gender,age and cause of CKD etc.)have been found to generate significant influence on CKD patients.Therefore it is reasonable to taken all these factors into consideration when evaluating vascular calcification without isolation.