Patients Undergoing Maintenance Peritoneal Dialysis Research Articles

Correlation of hematocrit and cardiovascular events in peritoneal dialysis patients

Objective: To investigate the correlation between hematocrit (HCT) and cardiovascular events in peritoneal dialysis (PD) patients. Methods: Patients undergoing maintenance PD in the PD center of Guizhou Provincial People's Hospital from March 19, 2012 to July 9, 2020 were included. Demographic, baseline clinical and laboratory data of the patients were collected and patients were followed up until April 8, 2022. The primary endpoint was the first occurrence of a cardiovascular event. According to the tertiles of baseline HCT, the patients were divided into group Q1 (HCT≤26.6%), group Q2 (HCT>26.6%-32.4%), and group Q3 (HCT>32.4%). Laboratory indexes and cardiovascular events were compared among the three groups. Kaplan-Meier survival curve, Cox regression analysis and sensitivity analysis were used to analyze the effect of HCT on cardiovascular outcomes. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of HCT for cardiovascular events in PD patients. Results: A total of 860 PD patients were included, including 494 males (57.4%) and 366 females (42.6%), with a mean age of (41.5±15.0) years. There were 287 cases in group Q1, 289 cases in group Q2, and 284 cases in group Q3, respectively. A total of 265 (30.8%) patients experienced first cardiovascular events during the follow-up period. The incidence of cardiovascular events in groups Q1, Q2 and Q3 was 36.2% (104/287), 34.3% (99/289), and 21.8% (62/284), respectively, with a statistically significant difference (P<0.001). The incidence of cardiovascular events decreased with the increase of HCT. Multivariate Cox proportional hazards regression model analysis showed that decreased HCT was a risk factor for cardiovascular events. Compared with group Q3, the risk of cardiovascular events in group Q1 increased by 50.7% (group Q2: HR=1.444, 95%CI: 1.029-2.028, P=0.034; group Q1: HR=1.570, 95%CI: 1.096-2.250, P=0.014). In the sensitivity analysis, using kidney transplantation as the competition event, the risk of cardiovascular events was lower in group Q3 than that in group Q1 (subdistributional HR=1.413, 95%CI: 1.006-1.990, P=0.046). Kaplan-Meier survival curve showed that compared with the other two groups, the cardiovascular events-free survival rate of patients in group Q1 was significantly lower (log-rank χ2=9.722, P=0.008). ROC analysis showed that the area under the curve (AUC) of HCT for predicting cardiovascular events in PD patients was 0.583 (95%CI: 0.542-0.623, P<0.001), with the sensitivity of 40.6% and the specificity of 75.1%. Conclusion: Low-level HCT is associated with an increased risk of the first cardiovascular event in PD patients.

Comparison of clinical outcomes between culture-negative and positive peritonitis in patients undergoing maintenance peritoneal dialysis: a prospective cohort study

BackgroundCulture-negative peritonitis is a serious complication in patients undergoing maintenance peritoneal dialysis (PD) and occurs in up to 40% of all peritonitis episodes. Despite its high incidence, data regarding treatment response and prognosis remain poorly defined. This study compared the clinical outcomes of patients with culture-negative and positive peritonitis.MethodThis prospective cohort study was conducted between 2021 and 2022. Patients treated with maintenance PD who developed PD-associated peritonitis were included and received standard treatment. The primary endpoint was the primary response (resolution of peritonitis 10 days after the initiation of treatment).ResultsOf the 81 patients who developed PD-associated peritonitis during the study, 35 and 46 had culture-negative and culture-positive peritonitis, respectively. Overall, 52 (64.2%) patients achieved the primary response: 24 (68.6%) in the culture-negative group and 28 (60.9%) in the culture-positive group (p = 0.630). There were no significant differences between the two groups in the incidence of complete cure (complete resolution of peritonitis without the need for Tenckhoff catheter removal or salvage antibiotic therapy or peritonitis within 120 days after treatment) (culture-negative vs. culture-positive group, 57.1% vs. 45.7%), refractory peritonitis (28.6% vs. 41.3%), relapse peritonitis (8.6% vs. 2.2%), repeat peritonitis (11.4% vs. 10.9%), salvage antibiotics (40.0% vs. 50.0%), permanent hemodialysis transfer (11.4% vs. 10.9%), Tenckhoff catheter removal (25.7% vs. 41.3%), or mortality (2.9% vs. 2.2%) (all p > 0.05).ConclusionThis study offers valuable insights into the clinical outcomes of culture-negative peritonitis versus culture-positive peritonitis. However, caution must be exercised in interpreting these findings due to the limitations of the small sample size.Clinical trial registrationThe study was retrospectively registered in the Thai Clinical Trials Registry (TCTR20221130006).

Aberrant serum parathyroid hormone, calcium, and phosphorus as risk factors for peritonitis in peritoneal dialysis patients

Identifying modifiable risk factors of peritoneal dialysis (PD)-related peritonitis is of clinical importance in patient care. Mineral bone disease (MBD) has been associated with mortality and morbidity in end-stage kidney disease (ESKD) patients. However, its influence on PD related peritonitis due to altered host immunity remains elusive. This study investigated whether abnormal biomarkers of MBD are associated with the development of peritonitis in patients undergoing maintenance PD. We conducted a retrospective observational cohort study, analysing data derived from a nationwide dialysis registry database in Taiwan, from 2005 to 2012. A total of 5750 ESKD patients commencing PD therapy during this period were enrolled and followed up to 60 months or by the end of the study period. The patients were stratified based on their baseline serum parathyroid hormone (PTH) levels, calcium (Ca) levels or phosphorus (P) levels, respectively or in combinations. The primary outcome was the occurrence of first episode of peritonitis, and patient outcomes such as deaths, transfer to haemodialysis or receiving renal transplantation were censored. Peritonitis-free survival and the influence of PTH, Ca, P (individual or in combination) on the peritonitis occurrence were analysed. A total of 5750 PD patients was enrolled. Of them, 1611 patients experienced their first episode of peritonitis during the study period. Patients with low PTH, high Ca or low P levels, respectively or in combination, had the lowest peritonitis-free survival. After adjusting for age, sex and serum albumin levels, we found that the combinations of low PTH levels with either high Ca levels or low/normal P levels were significant risk factors of developing peritonitis. Abnormal mineral bone metabolism in maintenance PD patients with low serum PTH levels, in combination with either high Ca levels or low/normal P levels, could be novel risk factors of PD-related peritonitis.

Relationship Between Thyroid Hormones and Left Ventricular Mass in Peritoneal Dialysis Patients.

Introduction. Non-thyroidal illness is prevalent in patients with advanced stages of chronic kidney disease and could be considered as a risk factor for cardiovascular mortality; this relation is partially explained by malnutrition and the concomitant condition of high inflammation. This study is designed to investigate the relationship between left ventricular mass and thyroid hormone abnormalities and evaluate this relationship after adjustment of inflammatory factors and nutritional status in peritoneal dialysis patients. Methods. A total of 71 patients undergoing maintenance peritoneal dialysis were included. Serum concentration of total and free triiodothyronine (fT3), total and free thyroxine (fT4), and TSH were measured. LV mass index and the structural properties of heart including LVEDD, LVESD, PWD, and EF were assessed by transthoracic echocardiography. The Surrogates of Inflammation, including IL-6, albumin, and hs-CRP were measured. The nutritional status of patients was assessed by one point SGA scoring and biochemical data. The relation between thyroid hormones and echocardiographic variables, inflammatory and nutritional markers was determined. Results. LVMI was significantly higher in the group with lower fT3 levels. Linear regression analyses showed statistically significant univariate association between fT3, tT3, and tT4; and LVMI. In multiple linear regression analysis adjusted for albumin, hs-CRP, IL- 6, and ferritin; only fT3 level had a meaningful negative correlation (P < .05) with LVMI, free T3 level was positively correlated with rGFR (P < .05, c = 0.39) and KT/V (P < .05, c = 0.27). Conclusion. Low fT3 level was negatively and significantly associated with LVML even after adjustments for known risk factors in peritoneal dialysis patients.

SAT-294 The relationship between peritoneal dialysis mortality and the Chinese medical insurance

There are two major medical insurance models in China: the Urban Basic Medical Insurance (UBMI) and the New Cooperative Medical Scheme (NCMS). We have observed that Chinese medical insurance type may affect the outcomes of patients treated with hemodialysis. The aim of the present study was to evaluate the association of the medical insurance type of patients undergoing peritoneal dialysis (PD) with their survival. We retrospectively analyzed the end-stage renal disease (ESRD) adult patients initiating PD between January 2008 and December 2016 in Zhejiang province, followed up through December 31, 2017. Patients had received continuous ambulatory PD for over 3 months, whom were divided into two groups according to their medical insurance type. Demographic, education level, clinical data, biochemical parameters and primary clinical outcomes including all-cause mortality, switch to hemodialysis and kidney transplant were analyzed. The survival rates were calculated by using the Kaplan-Meier method. A total of 8065 patients were enrolled, which is the largest cohort in China so far. There were 3523 patients (2090 males(59.3%)) with UBMI and 4542 (2317 males (51.0%)) with NCMS enrolled from 92 peritoneal dialysis units. Compared with UBMI, patients with NCMS were older (50 (IQR: 41-62) years old vs. 53 (IQR: 44-64)years old, P<0.001), had lower education level, smaller proportion of diabetic nephropathy and malignancy, more severe anemia, and more frequent hypoalbuminemia and hypocalcemia. The 1-, 3- and 5-year overall survival rates were 97.5%, 88.9%, and 81.5% in UBMI group, 95.9%, 85.9%, and 76.7% in NCMS group, respectively. Patients with NCMS showed higher all-cause mortality compared with UBMI (P<0.001). In multivariate Cox proportional hazards model, NCMS was independently associated with higher mortality (AHR=1.288; 95% CI 1.110,1.494). The medical insurance model was independently associated with PD patient survival, NCMS was associated with increased mortality among patients undergoing maintenance peritoneal dialysis in China.

Studies on the relationship of vitamin D receptor gene distribution and bone mineral density in patients with maintenance peritoneal dialysis

Objective To explore frequency distribution of vitamin D receptor (VDR) genotype and the correlations between polymorphism of VDR gene BsmⅠsites and bone mineral density in the patients undergoing maintenance peritoneal dialysis. Methods A case-control study was conducted based on 82 patients with maintenance peritoneal dialysis and 80 healthy people. The frequency distribution of VDR genotype in two groups was detected and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Serum biochemistry and bone mineral density of the patients undergoing maintenance peritoneal dialysis were detected by dual energy X-ray absorption (DEXA) and automatic biochemical analyzer, respectively. All data was analyzed with SPSS 19.0 software. Results The frequency distribution of VDR genotype between case group and control group had no significant difference (P>0.05). The serum biochemical index such as Ca, P, alkaline phosphatase (ALP) and parathyroid hormone (PTH)] of patients with maintenance peritoneal dialysis had no significant difference among three VDR genotypes(P>0.05). Compared to VDR bb genotype, the serum Ca was significantly higher in VDR BB genotype (P<0.05). The bone mineral density (BMD) and T-Score of patients with VDR BB genotype were the lowest, the BB genotype was the highest, and the difference was statistically significant among three genotypes (P<0.05). Conclusions The frequency distribution of VDR genotype between case group and control group had no significant difference. However, there is a correlation between VDR gene BsmⅠsites and bone mineral density of maintenance peritoneal dialysis patients. Key words: Peritoneal dialysis; Receptors, calcitriol/GE; Bone density

Associations of metabolic syndrome and its components with cardiovascular outcomes among non-diabetic patients undergoing maintenance peritoneal dialysis

Metabolic syndrome (MS) is thought to be a risk marker for cardiovascular diseases in the general population and in patients with chronic kidney disease. This study investigated whether the presence of MS also modifies cardiovascular (CV) outcomes among non-diabetic patients undergoing long-term peritoneal dialysis (PD). We enrolled 280 patients from a medical centre in North Taiwan who began PD between January 1999 and December 2005 and followed them until December 2009. MS was defined by the modified National Cholesterol Educational Programme (Adult Treatment Panel III) criteria. All parameters and biochemical data were collected by chart review. Patient outcomes (overall and CV death, fatal or non-fatal CV events) were recorded during the follow-up period. Survival was analysed by the Kaplan-Meier method, and the influence of MS and its components on outcomes were analysed by Cox regression models. The average follow-up period was 49.2 months. Non-diabetic patients with MS had worse outcomes than those without MS or at risk for MS, but better than their diabetic counterparts. By multivariate analysis, MS was independently associated with increased risk for CV death (hazard ratio, HR = 13.27) and fatal or non-fatal CV events (HR = 10.50). Among five MS components, hypertriglyceridaemia, low high-density lipoprotein levels and hyperglycaemia were significant risk factors for adverse CV outcomes. MS is a potent risk marker for adverse CV outcomes in non-diabetic patients on PD. Timely interventions targeting specific component of this syndrome may be required in this subset of patients.

Peritoneal Adipocytes and Their Role in Inflammation during Peritoneal Dialysis

Adipose tissue is a major site of chronic inflammation associated with peritoneal dialysis (PD) frequently complicating peritonitis. Adiposity-associated inflammation plays a significant contributory role in the development of chronic inflammation in patients undergoing maintenance PD. However, the molecular and cellular mechanisms of this link remain uncertain. Adipose tissue synthesizes different adipokines and cytokines that orchestrate and regulate inflammation, insulin action, and glucose metabolism locally and systemically. In return, inflammation retards adipocyte differentiation and further exacerbates adipose dysfunction and inflammation. An understanding of the inflammatory roles played by adipose tissue during PD and the healing mechanism of injured mesothelium will help to devise new therapeutic approach to slow the progression of peritoneal damage during peritoneal dialysis. This article reviews the roles of peritoneal adipose tissue in chronic peritoneal inflammation under PD and in serosal repair during PD.

Procalcitonin Fails to Differentiate Inflammatory Status or Predict Long-Term Outcomes in Peritoneal Dialysis-Associated Peritonitis

Peritonitis is the major complication in patients undergoing maintenance peritoneal dialysis (PD) and is associated with a significant risk of mortality. Previously, we have shown that patients treated for peritonitis and having prolonged elevation of C-reactive protein (CRP) are associated with higher mortality. The underlying cause for the chronic systemic inflammation remains unknown. We studied serum procalcitonin (PCT), which has been reported as an accurate marker for infection and inflammation, with respect to being a diagnostic and prognostic indicator of persistent chronic inflammation after peritonitis in patients with PD-related peritonitis. We conducted a prospective study on PD patients that developed PD-related peritonitis. Blood samples obtained at routine check-up before the onset of peritonitis were taken as baseline (D0). When patients developed PD-related peritonitis, serial blood samples were obtained on day 1 (D1), day 7 (D7), and day 42 (D42) for PCT, CRP, and other inflammatory markers. Patients were followed up for at least 2 years, during which outcomes of peritonitis and causes of death were recorded. Serum levels of CRP and PCT at day 42 were analyzed to assess for long-term prognosis. 35 patients [female 42.9%; mean age 63.8 +/- 13.1 years; 12 (34.3%) diabetics] were recruited. The onset of peritonitis was 3.61 +/- 3.56 years after PD initiation and median residual renal function at that time was 1.06 (range 0 - 6.1) mL/min. Median total white cell counts in PD effluent at days 1, 3, 7, and 42 were 3505/mm(3) (range 377 - 20 500/mm(3)), 297 (8 - 5880)/mm(3), 34 (0 - 5290)/mm(3), and 10 (0 - 115)/mm(3), respectively. Twelve (34.3%) and 14 (40%) PD effluents grew gram-positive and gram-negative micro-organisms respectively; others were culture negative. Median PCT was increased significantly at day 1 [2.00 (0.12 - 58.7) ng/mL, p < 0.001], day 7 [0.76 (0.13 - 15.25) ng/mL, p < 0.001], and day 42 [0.30 (0.13 - 0.79) ng/mL, p = 0.005] compared to baseline [0.20 (0.09 - 0.69) ng/mL]. Seven of 35 patients had false-negative results on day 1 (range 0.12 - 0.46) when PCT <0.5 ng/mL was used as the cutoff value for diagnosing peritonitis. For the long-term prognostic outcome, CRP at day 42 was significantly better than PCT in assessing overall prognosis (CRP: AUC 0.712, 95% CI 0.534 - 0.890 vs PCT: AUC 0.652, 95% CI 0.448 - 0.855). In Kaplan-Meier survival analysis, patients with elevated CRP (>3.0 mg/L) were associated with poorer long-term survival (p = 0.04) but elevated PCT at the 25th, 50th, or 75th percentiles failed to provide prognostic value. PD patients after peritonitis may be associated with prolonged systemic inflammation. CRP was a better serum marker for monitoring inflammatory status and predicting long-term prognosis in our study. Although serum PCT is elevated in some patients at the time of peritonitis, its value in making a diagnosis and predicting long-term prognosis remains doubtful.

Effects of salmon calcitonin in treatment of osteoporosis in patients undergoing dialysis

To investigate the prevalence of osteoporosis in patients undergoing maintenance dialysis and explore the safety and efficacy of salmon calcitonin in maintenance dialysis patients underwent with osteoporosis. Double-energy X-ray bone density meter was used on 256 patients undergoing maintenance dialysis, 126 males and 130 females, aged 60 +/- 14 (22 -79), to measure the bone mineral density (BMD) at the lumbar spine and femoral neck. 108 of them with the T values < -2.5 s were diagnosed as with osteoporosis, and then were randomly divided into 2 equal groups matched in baseline age, sex, mode of dialysis, and levels of iPTH, ALP, and BMD: control group receiving oral administration of calcium carbonate 1500 mg tid and rocaltrol 0.25 microg qn for 18 months, and experimental group, received subcutaneous injection of salmon calcitonin (50 U) three times a week in addition. The BMD levels of lumbar spine and femoral neck, and serum intact parathyroid hormone (iPTH), calcium, phosphorus, and alkaline phosphatase (ALP) were assessed before treatment and 3, 6, 12, and 18 months after treatment. (1) The osteoporosis rate of the 256 maintenance dialysis patients was 42.19%. (2) The osteoporosis rate of the 201 patients undergoing maintenance hemodialysis (MHD) was 47.76%, significantly higher than that of the 55 patients undergoing maintenance peritoneal dialysis (21.82%, P < 0.01). (3) At the end of the trial, there was a significant increase of BMD of lumbar spine and femoral neck in the experiment group compared with the control group. (4) Compared with the control group, the serum ALP, iPTH, and BGP levels 3, 6, 12, and 18 months after treatment were all significantly lower than the baseline level and those of the corresponding control groups (all P < 0.01). The serum calcium of the control group at the end of experiment increased significantly in comparison with baseline level (P < 0.05). (5) No adverse events were found after the treatment of salmon calcitonin. Salmon calcitonin effectively increases the BMD of the maintenance dialysis patients and is well tolerated.

Peritoneal Fluid Eosinophilia in Patients Undergoing Maintenance Peritoneal Dialysis

In ten patients undergoing maintenance peritoneal dialysis, large numbers of eosinophils were found in the peritoneal fluid. A few of the affected patients complained of episodic abdominal pains, but there was no correlation between abdominal symptoms and the number of peritoneal fluid eosinophils. Microorganisms failed to grow on cultures of the peritoneal fluids, and results of tests for endotoxin were negative. The cause of eosinophilia could not be determined. Peritoneal fluid eosinophil counts were noted to be elevated soon after catheter insertion and initiation of peritoneal dialysis. In some patients, peritoneal fluid eosinophil counts spontaneously returned to normal despite continued peritoneal dialysis.