Soluble urokinase plasminogen activator receptor is associated with cardiovascular calcification in peritoneal dialysis patients.

BACKGROUND: Cardiovascular disease (CVD) is an important cause of morbidity and mortality in peritoneal dialysis (PD) patients. Cardiovascular calcification (CVC) is highly prevalent in PD patients and could predict their cardiovascular mortality. Soluble urokinase plasminogen activator receptor (suPAR) is closely associated with coronary artery calcification in hemodialysis patients and is an important predictor of CVD. However, the role of suPAR in PD patients is poorly understood. We investigated the relationship between serum suPAR and CVC in PD patients. METHODS: Abdominal aortic calcification (AAC) was assessed by lateral lumbar radiography, coronary artery calcification (CAC) by multi-slice computed tomography, and cardiac valvular calcification (ValvC) by echocardiography. CVC was defined as confirmed presence of calcification in one site (AAC, CAC, or ValvC). Patients were divided into CVC group and non-CVC group. Demographic characteristics, biochemical variables, comorbidities, PD regimen, serum suPAR, and medication were compared between the two groups. Logistic regression was conducted to determine association between serum suPAR and presence of CVC. The receiver-operator curve (ROC) was plotted to calculate the area under the curve (AUC) for suPAR to identify CVC and ValvC. RESULTS: Of 226 PD patients, 111 (49.1%) had AAC, 155 (68.6%) had CAC, and 26 (11.5%) had ValvC. There were significant differences in age, BMI, diabetes, white blood cell, phosphorus, hs-CRP, suPAR, time on dialysis, total volume of dialysate, ultrafiltration, volume of urine, and Kt/V between CVC and non-CVC group. Serum suPAR was associated with CVC by multivariate logistic regression analysis in PD patients, especially in elderly patients. The levels of serum suPAR were closely related to the degree of AAC, CAC, and ValvC in PD patients. The incidence of CVC was higher in patients with higher levels of suPAR. The ROC curve showed that serum suPAR had a predictive value for CVC (AUC = 0.651), especially for ValvC (AUC = 0.828). CONCLUSION: Cardiovascular calcification is prevalent in PD patients. High levels of serum suPAR are associated with cardiovascular calcification in PD patients, especially in elderly patients.

Cardiac valve calcification as a predictor of cardiovascular outcomes in peritoneal dialysis patients: an inverse probability of treatment weighting analysis.

BACKGROUND: Cardiovascular events (CVE) are the leading cause of death in peritoneal dialysis (PD) patients. The predictive value of cardiac valve calcification (CVC) for CVE in dialysis patients remains controversial. In particular, such studies are limited in PD patients. We aimed to examine the predictive role of CVC for CVE and cardiovascular mortality in PD patients. METHODS: A retrospective analysis was performed on patients who initiated PD in our hospital. According to the result of echocardiography, patients were divided into CVC group and non-CVC group. The differences in baseline demographic characteristics, biochemical variables, comorbidities, and clinical outcomes between the two groups were compared. Kaplan-Meier method was used to obtain survival curves. The Cox regression model was used to evaluate the influence of CVC for cardiovascular outcomes. The inverse probability of treatment weighting (IPTW) was used to eliminate influence of the confounders in the groups. RESULTS: 458 peritoneal dialysis patients were enrolled in this study. 77 patients were in CVC group and 381 patients in non-CVC group. The average follow-up time was (32 ± 21) months. At baseline, the absolute standardized difference (ASD) of age, BMI, history of CVE, diabetes, LVEF, LVMI, albumin, calcium, phosphorus, triglycerides, hsCRP, urine volume, Kt/V, statins and vitamin D intake rate were greater than 0.1 between the two groups. All of ASD dropped to less than 0.1 after IPTW, which meant that the balance had been reached between the two groups. Multivariable logistic analysis showed that advanced age, diabetes, and hyperphosphatemia were associated with CVC. The Kaplan-Meier survival curve showed the cumulative CVE-free survival rate and cardiovascular survival rate of CVC group were significantly lower than that of non-CVC group before and after IPTW (log-rank P < 0.05). After IPTW was used to eliminate the effect of confounders, multivariate Cox regression analysis still showed CVC was an independent risk factor for CVE (HR = 2.383, 95% CI 1.331~4.264, P = 0.003) and cardiovascular mortality (HR = 2.347, 95% CI 1.211~4.548, P = 0.012) in PD patients. CONCLUSION: The prevalence of CVC is high in peritoneal dialysis patients. CVC is an independent risk factor for CVE and cardiovascular mortality in peritoneal dialysis patients.