Characteristics And Related Factors Of Cardiovascular Calcification In Maintainace Hemodialysis Patients

Cardiovascular disease (CVD) for chronic kidney disease (CKD) in patients with end-stage renal failure cause of 40%-50% death. Cardiovascular calcification is one of the main causes of CVD in patients with CKD. The traditional risk factors can not fully explain the cardiovascular calcification with CKD patients especially in maintenance hemodialysis patients. Chronic kidney disease mineral abnormal bone metabolism (CKD-MBD) is associated with cardiovascular calcification in CKD patients. The study still lacks in Chinese dialysis population about cardiovascular calcification incidence, distribution, development and influence factors. The purpose of this study is to get the prevalence,distribution and related factors of cardiovascular calcification in maintenance hemodialysis patients. And to evaluate the relationship between CKD-MBD index and cardiovascular calcification, the progression of cardiovascular calcification and to verify cardiovascular calcification risk factors.Study I Characteristics and Related Factors of Cardiovascular Calcification in Maintainace Hemodialysis PatientsObjective:To explore the distribution of cardiovascular calcification in maintenance hemodialysis patients and its related factors. Methodology:In total,144 adult patients(>18 years old) were enrolled, who had received maintenance hemodialysis for over 3 months at the blood purification center of our hospital between June and September 2013. This was a cross-sectional observational study,without intervention of the treatment strategy. Detect coronary artery calcification score(CACS, Agaston score) by spiral CT detection, abdominal aortic calcification score(AACS, Kauppila score) by abdominal lateral radiographs,and detect heart valve calcification by cardiac ultrasound, calculate the cardiovascular calcification index (CCI). Results:The calcification occurrence in any part was 70.83%. The proportion of CACS^ 100 was 50.67%. The proportion of AACS≥ 5 was 48.48%.In patients with valvular calcification mitral valve calcification dominated (34.25%).The calcification of the three parts developed with age and the dialysis vintage. AACS was positive correlation with CACS (Pearson r=0.5970), the occurrence of valve calcification in patients with higher CACS and AACS (p<0.001).Comparation of the two groups of patients with or without calcification of three parts showed differences between the age, dialysis vintage, body mass index, waist, ankle brachial index, serum creatinine, serum albumin, total cholesterol, low density lipoprotein, super sensitivity C reactive protein and whether diabetes patients. The advanced age, long dialysis vintage,hypercalcemia, anemia,dyslipidemia were independent risk factors for severe cardiovascular calcification. Comparing patients’CCI and CACS, the area under the receiver operating characteristic (ROC) curve (AUC) was 0.8371 (p<0.001).Conclusion: The total calcification occurrence was 70.83%. The advanced age, long dialysis vintage, anemia, hypercalcemia, dyslipidemia are independent risk factors for cardiovascular calcification. CCI have the potential to be a recommendable standard for evaluate cardiovascular calcification of maintainace hemodialysis patients.Study Ⅱ Maintain serum calcium,phosphorus and iPTH within standards and its relationship with the distribution of cardiovascular calcificationObjective:To observe the major indicators of CKD-MBD in maintainace hemodialysis patients:serum calcium, phosphorus, intact parathyroid hormone (iPTH) and the relationship between them and the distribution of cardiovascular calcification.Methodology:The subjects and data collection were as same as Study Ⅰ. Reference to Kidney Disease:Improving Global Outcomes (KDIGO) guidelines, this group of patients’ compliance rate of serum calcium was 63.3%, phosphorus 50%, intact parathyroid hormone (iPTH) 41.7%. High serum calcium (>2.5mmol/L) ratio was 37.5%. High phosphorus (> 1.78mmol/L) ratio was 31.9%. High iPTH (≥ 600pg/ml) ratio was 34.7%.Results:When serum phosphorus, calcium and phosphorus was accorded with the standards, patients without coronary calcification accounted for the largest proportion (60.0% and 60.0%), whereas the calcium and all the three index attached standard patients account for 25.0% and 30.8%.Which is similar that, when phosphorus,calcium and phosphorus attach to standards, patients without abdominal aortic calcification accounted for the largest percentage of patients (50.0% and 77.8%).Also in the comparison of valvular calcification, when phosphorus,calcium and phosphorus attached the standards, patients without valve calcification accounted for the largest percentage (50% and 77.8%). When comparing the number of cardiovascular calcification site, when phosphorus, phosphorus and iPTH, calcium and phosphorus attached the standards, patients were at the lowest percentage of calcification in all of the 3 parts (19%,15% and 11%). The similar effects on the cardiovascular calcification when serum calcium and all the three index attached the standard was not so significant.Conclusion:Patients with serum phosphorus lever on standards have a less incidence of cardiovascular calcification.Study Ⅲ The relationship between serum FGF23 lever with cardiovascular calcification and left ventricular mass indexObjective:To further clarify the relations between serum FGF23 lever and vascular calcification and left ventricular mass index (LVMI).Methods:We performed a cross-sectional observation on 182 cases of maintainace hemodialysis patients in our hospital.We detected serum intact FGF23, serum calcium and phosphorus, intact parathyroid hormone (iPTH),25 hydroxy vitamin D, and routine laboratory examination index, recorded the agents for regulating the metabolism of calcium and phosphorus.Patients undergone spiral CT to get coronary calcification score (CACS), abdominal lateral plain film examine to get abdominal aortic calcification score (AACS), cardiac ultrasound examine to get cardiac indexs. Results:The blood FGF23 (pg/ml) levels in this group of MHD patients significantly increased.According to the level of FGF23 the patients were divided into four groups:group 1 (77.7-1260.8), group 2 (1290.9-5934.6), group 3 (6969.8-27219.7), group 4 (27487.3,-234869.2) (pg/ml).With the increasing of FGF23 between groups, the patients were older, ankle brachial index was higher, hemoglobin was lower, serum phosphorus was higher (p<0.05).The serum 25 (OH) D levels showed a decreased trend,and lgiPTH, prescription of vitamin D, Left ventricular mass index (LVMI), the prevalence of left ventricular hypertrophy (LVH) showed an upward trend, but the difference was not statistically significant. In addition to the AACS ^5 patients the prevalence of abdominal aortic calcification increased with FGF23 elevation (p=0.048), the prevalence and severity of vascular calcification of the other groups had a rising trend, but the difference was not statistically significant. Conclusion: The serum FGF23 level increased significantly in maintainace hemodialysis patients,which was closely related with the increase of serum phosphorus level. No correlation between FGF23 and coronary artery calcification, LVMI and prevalence of LVH was found.Study Ⅳ The progression of coronary artery calcification and left ventricular mass indexObjective:To explore the progression of coronary artery calcification and left ventricular mass index in maintenance hemodialysis patients. Methodology:Altogether 95 maintenance hemodialysis patients in Blood Purification Center of Nanjing General Hospital finished 1 year follow-up. Quantify coronary artery calcification (CACS, Agaston score) by spiral CT detection at baseline and after 1 year. Record the baseline clinical and laboratory data, while detect the heart function indexes by echocardiography.ResuIts:The prevalence rate of CACS>0 increased from 48.42% to 53.68%, mean value increased from 272.12 to 390.94, but the difference was not statistically significant. The growth rate of CACS was 116.61±162.90 (%).The patients in CACS pogressed group were older, have larger abdominal circumference, higher fasting blood sugar, higher sensitive C reactive protein,and a higher proportion of patients with diabetes mellitus. Serum calcium, serum phosphorus, parathyroid hormone,25 hydroxy vitamin D, calcium and phosphorus levels of drug use showed no difference. Logistic regression analysis showed that the independent risk factors related in CACS increase include age,serum calcium, sensitive C reactive protein, serum calcium,fibroblast growth factor 23, diastolic blood pressure and plasma homocysteine, the independent protective factors include 25 hydroxyvitamin D and ferritin. The growth of CACS of group b (baseline, CACS≥400) are significantly higher than that of group a (baseline 0<CACS< 400). The left ventricular mass index of both groups were significantly increased (p=0.039 and 0.026, respectively) after 1 years of follow-up, but group b progressed faster than group a.The incidence of left ventricular ejection fraction and the ratio of E/A and left ventricular hypertrophy were not statistical significant in the difference between the baseline and follow-up after 1 years. Conclusion:CACS of this group of patients mildly elevated without statistical significance comparing baseline and 1 year later.The degree of calcification calcification in patients with high baseline CACS (≥400)progress faster and their left ventricular mass index increased more obviously. Age, waist circumference, blood glucose, diabetes, inflammation, serum calcium,fibroblast growth factor 23 is related to the development of coronary artery calcification in maintainace hemodialysis patients independently.Summary The total incidence of cardiovascular calcification in this group of MHD patients is 70.83%, which is relatively low compared with data from literature.In addition to traditional risk factors, serum calcium is related.Patients with blood phosphorus within standards have fewer parts and a lesser degree cardiovascular calcification. Circulating FGF23 level increased significantly, associated with serum phosphorus level. No correlation between FGF23 and LVMI,LVH and coronary artery calcification was found, but the elevated FGF23 leads to increased LVMI trend. The average CACS mildly elevated 1 year after. The patients with higher baseline CACS made a greatly degree of progress, left ventricular mass index increased obviously. Age, waist circumference, blood glucose, diabetes, inflammation, serum calcium, FGF23 are risk factors of the progress of coronary artery calcification. CCI may be a recommendable evaluation index of vascular calcification. In conclusion, control CKD-MBD index within standard, inhibition of FGF23 generation, is expected to reduce the occurrence and development of cardiovascular calcification and myocardial remodeling.