Calcium-based phosphate binders and bone mineral density in patients undergoing hemodialysis: a retrospective cohort study.

BACKGROUND: Calcium supplements are commonly prescribed to prevent fractures in patients with osteoporosis. Nonetheless, they are generally eschewed in hemodialysis patients because they increase vascular calcification and induce cardiovascular disease. This retrospective cohort study aimed to investigate the effect of calcium-based phosphate binders (CBPB) on bone mineral density (BMD) in hemodialysis patients. METHODS: Outpatients on dialysis who underwent BMD measurement from January to December 2017, whose data on BMD trends and CBPB administration were recorded over the next 4 years, were enrolled. Patients receiving anti-osteoporotic medications were excluded. The association between the presence and duration of CBPB administration and changes in BMD was evaluated. RESULTS: The femoral neck's BMD decreased from 0.836 g/cm2 (0.702-0.952) to 0.764 g/cm2 (0.636-0.896) (P < 0.001) in the non-CBPB group (patients who never received CBPB over 4 years, n = 32). The CBPB group (n = 56) exhibited only a minute decrease from 0.833 g/cm2 (0.736-0.965) to 0.824 g/cm2 (0.706-0.939) (P = 0.004). Multivariate linear regression analysis revealed better BMD maintenance in the CBPB group [ß-coefficient (95% CI): 0.033 (0.001-0.065); P = 0.046] than in the non-CBPB group. Additionally, the prolonged-CBPB administration group showed superior BMD preservation [ß-coefficient (95% CI): 0.038 (0.001-0.076); P = 0.042]. CONCLUSION: CBPB administration may be associated with BMD maintenance.

A multi-institutional, observational study of outcomes after catheter placement for peritoneal dialysis in Japan.

BACKGROUND: This multi-institutional, observational study examined whether the outcomes after peritoneal dialysis (PD) catheter placement in Japan meet the audit criteria of the International Society for Peritoneal Dialysis (ISPD) guideline and identified factors affecting technique survival and perioperative complications. METHODS: Adult patients who underwent first PD catheter placement for end-stage kidney disease between April 2019 and March 2021 were followed until PD withdrawal, kidney transplantation, transfer to other facilities, death, 1 year after PD start or March 2022, whichever came first. Primary outcomes were time to catheter patency failure and technique failure, and perioperative infectious complications within 30 days of catheter placement. Secondary outcomes were perioperative complications. Appropriate statistical analyses were performed to identify factors associated with the outcomes of interest. RESULTS: Of the total 409 patients, 8 who underwent the embedded catheter technique did not have externalised catheters. Of the 401 remaining patients, catheter patency failure occurred in 25 (6.2%). Technical failure at 12 months after PD catheter placement calculated from cumulative incidence function was 15.3%. On Cox proportional hazards model analysis, serum albumin (hazard ratio (HR) 0.44; 95% confidence interval (CI) 0.27-0.70) and straight type catheter (HR 2.14; 95% CI 1.24-3.69) were the independent risk factors for technique failure. On logistic regression analysis, diabetes mellitus was the only independent risk factor for perioperative infectious complications (odds ratio 2.70, 95% CI 1.30-5.58). The occurrence rate of perioperative complications generally met the audit criteria of the ISPD guidelines. CONCLUSION: PD catheter placement in Japan was proven to be safe and appropriate.

Venous Hypertension Improved by a Viabahn Stent Graft Blocking Regurgitation to the Periphery of the Basilic Vein in an Elderly Patient Undergoing Hemodialysis: A Case Report.

Although necessary for hemodialysis (HD), arteriovenous grafts (AVG) frequently cause complications. Stenosis resulting in venous hypertension is a concern for physicians. Herein, we describe how venous hypertension was improved by using a Viabahn stent graft in an elderly HD patient. An 86-year-old woman started maintenance HD with a left-arm AVG. Two years later, she was referred to our hospital for treatment of juxta-graft-venous junction (GVJ) stenosis. Because of recurrence of stenosis at the juxta-GVJ, she underwent four percutaneous transluminal angioplasty (PTA) procedures during a period of 9 months. One month after the most recent PTA, the patient had redness, swelling, and pain in her left forearm. Venous hypertension was diagnosed on the basis of angiography findings showing regurgitation to the periphery of the basilic vein and juxta-GVJ stenosis. The stenosed juxta-GVJ was adequately expanded with a 7-mm balloon, and a 7-mm stent graft was inserted into the stenosis site. After successful treatment, there was no regurgitation to the periphery of the basilic vein and no symptoms. This complication should be considered when an AVG is created, because cutting off peripheral veins might prevent venous hypertension. Clinicians should perform regular postoperative monitoring.

Parathyroid hormone levels and pulse wave velocity in hemodialysis patients.

INTRODUCTION: We conducted an observational study to test the hypothesis that intact parathyroid hormone (PTH) levels are independently associated with pulse wave velocity (PWV), indicating arteriosclerosis progression. METHODS: In this cross-sectional study, patients on hemodialysis in whom brachial-ankle PWV (baPWV) was measured from November 2020 to November 2021, were included. RESULTS: One hundred seventy-four patients, with a mean age of 69.9 years (standard deviation [SD], 11.9), were included in this study. In multivariate linear regression analysis, serum intact PTH levels were correlated with baPWV (ß coefficient: 95% confidence interval [CI], 2.1 [0.22, 3.99]; p = 0.029). The subgroup analysis, which was divided according to the presence of diabetes, showed that diabetes has a significant interaction between PTH and PWV. CONCLUSION: These results suggest that intact PTH is independently associated with PWV. Moreover, physiological mechanisms characteristic of diabetes may be involved in the association between PTH and arteriosclerosis.

Factors affecting the relationship between ionized and corrected calcium levels in peritoneal dialysis patients: a retrospective cross-sectional study.

BACKGROUND: Chronic kidney disease-mineral and bone disorder (CKD-MBD) management in patients with end-stage renal disease is important owing to the risk of cardiovascular diseases. In clinical practice, we manage patients not by monitoring the levels of biologically active ionized calcium (iCa) but by monitoring total serum calcium or corrected calcium (cCa). We previously reported that iCa/cCa ratio was different between patients with hemodialysis and those with peritoneal dialysis (PD). In PD patients, several factors are expected to affect iCa/cCa ratio. Therefore, modifying the strategy to achieve better CKD-MBD management might be necessary; however, no reports have studied this to date. Therefore, we investigated the factors influencing iCa/cCa ratio in PD patients. METHODS: This retrospective cross-sectional study examined background and laboratory data, including iCa, collected at routine outpatient visits. The patients were divided into the first, second, and third tertile of iCa/cCa ratio groups to compare patient background and laboratory data. Multiple regression analysis was used to investigate the factors influencing iCa/cCa ratio. We used multiple imputation to deal with missing covariate data. RESULTS: In total, 169 PD patients were enrolled. In PD patients with lower iCa/cCa ratio, PD duration was longer and pH was higher. Urine volume and weekly renal Kt/V were lower in the patients with lower iCa/cCa ratio than in those with higher iCa/cCa ratio. iCa/cCa ratio and weekly renal Kt/V were directly correlated (r = 0.41, p < 0.01), and weekly renal Kt/V and pH were independent factors affecting iCa/cCa ratio (t = 2.86, p < 0.01 and t = - 5.42, p < 0.01, respectively). CONCLUSIONS: iCa levels were lower in PD patients with lower residual renal function (RRF) even though their cCa levels were equal to those with maintained RRF, warranting caution in the assessment and management of CKD-MBD in PD patients.

Risk factors for encapsulating peritoneal sclerosis: Analysis of a 36-year experience in a University Hospital.

AIM: Encapsulating peritoneal sclerosis (EPS) is a rare but serious complication that occurs in peritoneal dialysis (PD) therapy. The present study aimed to identify the risk factors, especially peritonitis and biocompatible PD fluid. METHODS: The study included 703 patients who received PD between January 1980 and March 2015 at two centres. The patients were divided into two groups: those who had developed EPS (EPS group: n = 44) and those who had no documentary evidence of EPS (non-EPS group: n = 659). The independent risks of EPS were determined by univariate and multivariate logistic models. RESULTS: Encapsulating peritoneal sclerosis occurred in 44/703 (6.3%) patients between January 1980 and March 2015. In multivariate logistic models of risk factors correlated with EPS, dialysate to plasma creatinine ratio (D/P Cr) by peritoneal equilibration test (PET) and history of peritonitis were risk factors for EPS development (P < 0.01, respectively) in addition to PD duration. Especially, total duration of peritonitis, defined by period between onset and resolution of peritonitis, was an important risk factor for EPS development in patients with a history of peritonitis. Receiver operating characteristic (ROC) curve analysis revealed that cut-off point for EPS development was 36 days. Moreover, biocompatible PD fluid contributed to decreased EPS development. CONCLUSION: Both the longer duration of peritonitis and higher D/P Cr, as well as the longer PD duration, were risk factors for EPS development. Furthermore, use of biocompatible PD fluid contributed to the decrease in EPS development.

The differences in acid-base status and the calcium parathyroid axis between peritoneal dialysis and hemodialysis.

BACKGROUND: Several guidelines have set the target levels of serum Ca, phosphorus, and parathyroid hormone (PTH) for better management of chronic kidney disease-mineral and bone disorders (CKDMBD) in dialysis patients. Although serum ionized Ca (iCa) is a biologically active component, corrected Ca (cCa) is used in clinical settings. However, the association between iCa and cCa is affected by acid-base status. We investigated the difference in acid-base and the calcium-parathyroid status between hemodialysis (HD) and peritoneal dialysis (PD). METHODS: The markers associated with CKD-MBD were measured in 142 patients receiving chronic dialysis (69 on PD and 73 on HD). RESULTS: Serum bicarbonate levels were significantly higher in the PD group than in the HD group (26.6 ± 2.8 vs. 22.9 ± 2.0 mEq/L, p < 0.01). The serum iCa levels and the iCa/cCa ratio were significantly lower in the PD group than in the HD group (iCa 1.07 ± 0.08 vs. 1.14 ± 0.08 mmol/L, p < 0.01; iCa/cCa ratio 45.5 ± 3.1% vs. 49.7 ± 3.2%, p < 0.01). The cCa levels were significantly higher in the PD group than in the HD group (9.4 ± 0.4 vs. 9.1 ± 0.4 mg/dL, p < 0.01). Intact PTH levels were significantly higher in the PD group than in the HD group (220 (40 - 581) vs. 133 (30 - 666) pg/mL, p < 0.01). CONCLUSIONS: We found that PD patients had lower iCa and higher PTH levels despite higher cCa levels as compared to HD patients. These results suggested that the assessment of both Ca and PTH should be different between PD and HD.