Association of Pulmonary Hypertension with Mortality in Incident Peritoneal Dialysis Patients

♦ Background:

The prognostic value of pulmonary hypertension at the start of peritoneal dialysis (PD) in patient survival is unclear.

♦ Methods:

We conducted a retrospective study of incident patients who initiated PD therapy from January 2007 to December 2011, and followed up through June 2013. Pulmonary hypertension was defined as an estimated systolic pulmonary artery pressure (PAP) of ≥ 35 mm Hg using echocardiography. Clinical parameters and laboratory findings were compared between patients with and without pulmonary hypertension and a logistic regression model was elaborated. Patient outcomes (all-cause and cardiovascular mortality) were recorded during follow-up. Survival curves were constructed by the Kaplan-Meier method, and the influences of pulmonary hypertension on outcomes were analyzed by Cox regression models.

♦ Results:

Pulmonary hypertension was prevalent in 99 (16.0%) of the 618 patients studied. The independent risk factors for pulmonary hypertension were female (odds ratio [OR] = 2.12; 95% confidence interval [CI]: 1.29 – 3.46), left atrial diameter (OR = 1.15; 95% CI: 1.10 – 1.20), left ventricular ejection fraction (OR = 0.97; 95% CI: 0.95 – 0.99), and serum sodium (OR = 0.94; 95% CI: 0.89 – 0.99). Over a median follow-up of 29.4 months, 93 patients (15.0%) died, 59.1% of them due to cardiovascular disease. Kaplan-Meier survival analysis showed that patients with pulmonary hypertension had worse overall rates of survival and cardiovascular death-free survival than those without pulmonary hypertension. After multivariate adjustment, pulmonary hypertension was independently associated with increased risk for both all-cause and cardiovascular mortality, with hazard ratios (HRs) of 2.10 (95% CI: 1.35 – 3.27) and 2.60 (95% CI: 1.48 – 4.56), respectively.

♦ Conclusions:

The prevalence of pulmonary hypertension at the start of PD was common and associated with increased risk of both all-cause and cardiovascular mortality in incident PD patients.     

The Association Between Body Mass Index and Mortality on Peritoneal Dialysis: A Prospective Cohort Study

♦ Background: Previous studies have demonstrated that increased body mass index (BMI) is associated with decreased mortality in hemodialysis (HD) patients. However, the association between BMI and survival has not been well established in patients undergoing peritoneal dialysis (PD). The aim of the study was to determine the association between BMI and mortality in the PD population using the Clinical Research Center (CRC) registry for end-stage renal disease (ESRD) cohort in Korea.♦ Methods: Prevalent patients with PD were selected from the CRC registry for ESRD, a prospective cohort study on dialysis patients in Korea. Patients were categorized into four groups by quartiles of BMI. Cox regression analysis was used to calculate the adjusted hazard ratio (HR) of mortality with a BMI of quartile 2 (21.4 - 23.5 kg/m²) as the reference.♦ Results: A total of 900 prevalent patients undergoing PD were included. The median follow-up period was 24 months. The multivariate Cox proportional hazard model showed that the lowest quartile of BMI was associated with higher mortality (HR 3.00, 95% confidence interval (CI), 1.26 - 7.15). However, the higher quartiles of BMI were not associated with mortality compared with the reference category of BMI quartile 2 (Quartile 3: HR 1.11, 95% CI, 0.43 - 2.85, Quartile 4: HR 1.64, 95% CI, 0.66 - 4.06) after adjustment for clinical variables.♦ Conclusions: Lower BMI was a significant risk factor for death, but increased BMI was not associated with mortality in Korean PD patients.     

持续性腹膜透析和血液透析对慢性肾功能衰竭多发性神经病转归的影响

目的通过电生理测试结果评估持续腹膜透析（PD）或血液透析（HD）的慢性肾功能衰竭患者周围神经病的发生率,并根据残余肾功能判断透析方式对周围神经功能的影响。方法将131例慢性肾功能衰竭患者按透析方式分为HD组（n=73）和PD组（n=58）。根据透析治疗期间肌电图的结果分别将HD组、PD组各分为MN亚组和非MN亚组。采用德国Medelec Shaphire 2MED仪对每例患者的正中神经、尺神经、腓总神经和胫神经的神经传导速度（NCV）进行电生理测定,感觉神经检测包括波幅、潜伏期和传导速度;运动神经检测则包括复合肌肉动作电位的波幅、潜伏期和传导速度。电生理检测发现至少2条神经异常结果可诊断为多发性神经病。在透析开始后的第1、6、12、18、24月检测每位患者的残余肾功能。结果 131例患者中在观察末期有78例存在感觉障碍。78例患者经肌电图检查诊断为MN者77例,其中HD组中MN患者44例（60.3%）,PD组中MN患者33例（56.9%）,2组比较差异无统计学意义（P〉0.05）。透析治疗初期HD组中的MN亚组、非MN亚组,PD组中的MN亚组、非MN亚组对残余肾功能（RRF）变化进行多重比较,差异均无统计学意义（均P〉0.05）。随着透析的进行,第12、24个月2种透析组的MN亚组RRF显著下降（P〈0.05）,非MN亚组RRF比较差异无统计学意义（P〉0.05）。结论 MN在慢性肾衰患者中是常见的并发症,发生率与治疗方法无明显关系;PD或HD治疗不能阻止慢性肾功能衰竭患者周围神经病变的发生。残留肾功能在保护慢性肾功能衰竭患者周围神经功能方面起了重要的作用。     

慢性肾功能衰竭腹膜透析患者CA125检测的临床意义

【目的】探讨慢性肾功能衰竭腹膜透析患者透出液CA125检测的临床意义。【方法】本院行持续非卧床腹膜透析治疗的慢性肾功能衰竭患者42例,在透析开始前和透析开始后每个月,采用ELISA法检测CA125。采用4h腹膜平衡试验（4hD／PCr）评估腹膜转运功能。【结果】随着透析时间的延长,CA125浓度逐渐下降（F=8．564,P=0．000）;并且CA125与透析时间呈负相关,其相关系数为-0．513（t=4．211,P=0．032）。感染性腹膜炎组CA125水平明显高于同期非感染性腹膜炎组（t=5．704,P=0．000）。但不同的腹膜转运功能,CA125水平没有明显差异（F=1．522,P=0．241）,4hD／PCr和CA125也没有的相关性,相关系数为=0．342（t=0．871,P=0．524）。【结论】CA125在慢性肾功能衰竭腹膜透析患者透出液中的变化,可作为评价腹膜功能、判断腹膜腔感染的重要指标之一。     

Prospective Randomized Study Comparing a Single-Cuff Self-Locating Catheter with a Single-Cuff Straight Tenckhoff Catheter in Peritoneal Dialysis

♦ Objectives:

Peritoneal dialysis (PD) catheters are critical to the success of the technique. However, few studies provide evidence about which design helps to reduce complications. Self-locating catheters (SLCs) are used to avoid displacement of the catheter tip. The incidence of mechanical and infectious complications and catheter survival rate were assessed in Tenckhoff PD catheters.

♦ Design:

The prospective randomized study compared drainage problems in 40 incident PD patients using a single-cuff SLCs and 38 patients using a single-cuff, straight Tenckhoff catheter (TC).

♦ Results:

No significant differences were observed in the number of complications in the Pre period (from the insertion of the catheter to the start of the technique); however, the number of complications was lower in the SLC group during Post (p = 0.021) and Total period (p = 0.048). The number of problems related to catheter malfunction for each period: Pre, Post, and Total, was significantly lower with SLCs vs TCs (p = 0.018, p = 0.001 and p = 0.003, respectively). Problems were solved more easily with SLCs, using laxatives, with less need for fluoroscopic placement and no need for surgical replacement, as opposed to the TC group: Pre (not significant), Post (p = 0.007), and Total (p = 0.011).Median survival was 39.6 months (30.9 – 48.3) for SLCs and 30.1 months (22.6 – 37.5) for TCs, which is not a significant difference. However, SLCs have a higher malposition-free survival rate. Multivariate logistic regression models only included the variable “type of catheter” as a predictor of malfunction during the Pre period (odds ratio [OR] = 4.154). The Post period included the variables, “type of catheter” (OR = 7.701) and “age” (OR = 1.047), and the Total period only included the variable “type of catheter” (OR = 4.487), which indicates an increased probability of malfunction with the use of TCs vs SLCs. The variables (gender, previous intra-abdominal surgery, body mass index (BMI) and diabetes mellitus) did not add predictive value to the models (p > 0.05).

♦ Conclusion:

The study confirms the hypothesis that TCs have more malfunctions and a lower malposition-free survival rate than SLCs, and TCs are considered as the highest risk factor for malfunction during all study periods.     

Peritoneal Ultrafiltration in Refractory Heart Failure: A Cohort Study

♦ Introduction: Acutely decompensated heart failure (HF) in patients with diuretic resistance is often treated with extracorporeal ultrafiltration. Peritoneal ultrafiltration (PUF) has been proposed for the long-term management of severe HF after resolution of the acute episode. The aim of the present study was to evaluate the use of PUF in the treatment of chronic refractory HF in patients without end-stage renal disease.♦ Methods: This multicenter (10 nephrology departments throughout Italy) retrospective observational study included patients with severe HF refractory to maximized drug treatment. The patients were proposed for PUF because they had experienced at least 3 hospital admissions in the preceding year for acutely decompensated HF requiring extracorporeal ultrafiltration.♦ Results: Of the 48 study patients (39 men, 9 women; mean age 74 ± 9 years), 30 received 1 nocturnal icodextrin exchange, 5 required 2 daily exchanges, and 13 received 2 - 4 sessions per week of automated peritoneal dialysis. During the first year, renal function remained stable (initial: 20.8 ± 10.0 mL/min/1.73 m²; end: 22.0 ± 13.6 mL/min/1.73 m²), while pulmonary artery systolic pressure declined to 40 ± 6.09 mmHg from 45.5 ± 9.18 mmHg (p = 0.03), with a significant concomitant improvement in New York Heart Association functional status. Hospitalizations decreased to 11 ± 17 days/patient-year from 43 ± 33 days/patient-year before the start of PUF (p < 0.001). The incidence of peritonitis was 1 episode in 45 patient-months. Patient survival was 85% at 1 year and 56% at 2 years.♦ Conclusions: This study confirms the satisfactory results of using PUF for chronic HF in elderly patients.     

Effect of Biocompatible Peritoneal Dialysis Solution on Residual Renal Function: A Systematic Review of Randomized Controlled Trials

♦ Introduction: Residual renal function (RRF) plays an important role in outcome of peritoneal dialysis (PD) including mortality. It is, therefore, important to provide a strategy for the preservation of RRF. The objective of this study was to evaluate relative protective effects of new glucose-based multicompartmental PD solution (PDS), which is well known to be more biocompatible than glucose-based conventional PDS, on RRF compared to conventional PDS by performing a systematic review (SR) of randomized controlled trials.♦ Methods: We searched studies presented up to January 2014 in MEDLINE, EMBASE, the COCHRANE library, and local databases. Three independent reviewers reviewed and extracted prespecified data from each study. The random effects model, a more conservative analysis model, was used to combine trials and to perform stratified analyses based on the duration of follow-up. Study quality was assessed using the Cochrane Handbook for risk of bias. Eleven articles with 1,034 patients were identified for the SR.♦ Results: The heterogeneity of the studies under 12 months was very high, and the heterogeneity decreased substantially when we stratified studies by the duration of follow-up. The mean difference of the studies after 12 months was 0.46 mL/min/1.73 m² (95% confidence interval = 0.25 to + 0.67).♦ Conclusion: New PDS showed the effect to preserve and improve RRF for long-term use compared to conventional PDS, even though it did not show a significant difference to preserve RRF for short-term use.     

Fatigue in Peritoneal Dialysis Patients and an Exploration of Contributing Factors: A Cross-Sectional Study

ContextFatigue is a common and detrimental symptom in dialysis patients; however, our understanding of it and investigation of its contributing factors is still very limited, especially in peritoneal dialysis (PD) patients.ObjectivesTo assess fatigue in PD patients and identify contributing factors.MethodsOne hundred eight PD patients in a comprehensive hospital in China were recruited. The fatigue severity of the participants was assessed using the Chalder Fatigue Scale 11. Demographic factors and results of physiological tests were collected. Quality of sleep, mental health, and social support were assessed with the Pittsburgh Sleep Quality Index, Symptom Checklist 90, and Social Support Rating Scale, respectively. Multiple linear regression models were conducted with candidate variables with a P-value of less than 0.1 on univariate analysis and variables that were clinically relevant to identify contributing factors for fatigue.ResultsThe fatigue level in PD patients was significantly higher than the community population, and 78.7% of them were suffering from fatigue. The factors that were significantly associated with fatigue were quality of sleep, normalized protein nitrogen appearance, transferrin, alkaline phosphatase, and total cholesterol (adjusted R squared 0.86). Among them, quality of sleep, transferrin, alkaline phosphatase, and total cholesterol were significant contributors for physical fatigue, whereas the quality of sleep and normalized protein nitrogen appearance were contributing factors for mental fatigue.ConclusionFatigue is a common symptom in PD patients, suggesting that increased awareness of this symptom is required. The identification of correlates by extensive exploration of multidimensional factors in this study may help practitioners to identify patients at higher risk and to develop a multidimensional and targeted intervention plan.     

Associations Between Serum-Intact Parathyroid Hormone,Serum 25-Hydroxyvitamin D,Oral Vitamin D Analogs and Metabolic Syndrome in Peritoneal Dialysis Patients: A Multi-Center Cross-Sectional Study

♦ Introduction: Although previous studies have suggested associations between serum intact parathyroid hormone (iPTH), 25-hydroxyvitamin D (25(OH)D) and metabolic syndrome (MS) in the general population, these associations are still uncharacterized in peritoneal dialysis (PD) patients.♦ Methods: In total, 837 prevalent PD patients from 5 centers in China were enrolled between April 1, 2011 and November 1, 2011. The demographic data, biochemical parameters and medical records were collected, except for serum 25(OH)D which was measured in 347 of 837 patients. The definition of MS was modified from National Cholesterol Education Program Third Adult Treatment Panel (NCEP-ATPIII).♦ Results: 55.4% of 837 patients were found to have MS. The median concentration of iPTH, 25(OH)D and doses of oral vitamin D analogs for participants with MS was significantly lower than those without MS. The iPTH, 25(OH)D values and doses of vitamin D analogs were all associated with one or more components of MS. After multivariate adjustment, low serum iPTH values and oral vitamin D analogs, rather than serum 25(OH)D, were significantly associated with the presence of MS, abnormal fasting blood glucose (FBG) and high-density lipoprotein cholesterol (HDL-C). Compared to iPTH < 130pg/mL, iPTH 130-585 pg/mL and > 585pg/mL were associated with a lower risk of MS with adjusted odds ratio (OR) of 0.59 and 0.33, respectively. Taking vitamin D analogs was also associated with a lower risk of MS with adjusted OR of 0.55.♦ Conclusions: Serum iPTH and the use of active vitamin D supplements rather than serum 25(OH)D were independently associated with the presence of MS in patients on PD.     

规律门诊随访对腹膜透析患者高血压控制率及相关疾病转归影响的回顾性分析

目的 探究规律门诊随访对腹膜透析患者高血压控制率、高血压相关疾病转归、高血压相关可控因素的影响。方法 纳入2009年1月—2019年12月在本中心置管并随访的腹膜透析患者,查阅病历收集患者基线资料、血压资料和相关疾病的记录;调查研究截止时仍未退出腹膜透析的患者高血压相关可控因素。据随访频率分为规律随访组（≥1次/3月）和非规律随访组（<1次/3月）,比较2组的高血压控制情况。结果 本研究共纳入526例腹膜透析患者,规律门诊随访率为52.3%。规律随访是腹膜透析患者高血压控制的独立影响因素（OR=1.705,95%CI：1.090~2.666,P=0.019）。规律随访与高血压相关疾病转归（退出腹膜透析、心血管疾病、心力衰竭）的发生无影响。规律随访改善了高血压相关可控因素。结论 规律门诊随访是改善腹膜透析患者的高血压控制情况的有效手段,应不断提高随访的质量,鼓励患者定期进行门诊随访。     

The Risk Factors and the Impact of Hernia Development on Technique Survival in Peritoneal Dialysis Patients: A Population-Based Cohort Study

♦ Objectives:

There is a lack of consensus on the risk factors for hernia formation, and the impact on peritoneal dialysis (PD) survival has seldom been studied.

♦ Methods:

This was a population-based study and all collected data were retrieved from the National Health Insurance Research Database of Taiwan. Patients who commenced PD between January 1998 and December 2006 were screened for inclusion. Multiple logistic regression and Cox proportional hazards models were applied to estimate the predictors for hernia formation and determine the predictors of PD withdrawal.

♦ Results:

A total of 6,928 PD patients were enrolled and followed until December 2009, with 631 hernia events and 391 hernioplasties being registered in 530 patients (7.7%). The incidence rate was 0.04 hernias/patient/year. Longer PD duration (per 1 month increase, hazard ratio (HR) 1.019) and history of mitral valve prolapse (MVP) (HR 1.584) were independent risk factors for hernia formation during PD, and female gender (HR 0.617) was a protective factor. On the other hand, there were 4,468 PD withdrawals, with cumulative incidence rates of 41% at 1 year, 66% at 3 years, and 82% at 5 years. Independent determinants for cumulative PD withdrawal included hernia formation during PD (HR 1.154), age (per 1 year increase, HR 1.014), larger dialysate volume (per 1 liter increase, HR 0.496), female gender (HR 0.763), heart failure (HR 1.092), hypertension (HR 1.207), myocardial infarction (HR 1.292), chronic obstructive pulmonary disease (COPD) (HR 1.227), cerebrovascular accident (CVA) (HR 1.364), and history of MVP (HR 0.712)

♦ Conclusions:

Prolonged PD duration was a risk factor for hernia formation, and female gender was protective. Hernia formation during PD therapy may increase the risk of PD withdrawal.     

Serum Concentrations of p-Cresyl Sulfate and Indoxyl Sulfate,but Not Inflammatory Markers,Increase in Incident Peritoneal Dialysis Patients in Parallel with Loss of Residual Renal Function

♦ Background: High serum concentrations of the protein-bound uremic retention solutes p-cresyl sulfate (PCS) and indoxyl sulfate (IndS) and inflammation are associated with increased cardiovascular morbidity and mortality in chronic kidney disease. Renal clearance contributes to up to 80% of the total clearance of PCS and IndS in peritoneal dialysis (PD) patients. Cross-sectional studies evaluating the impact of residual renal function (RRF) on serum concentrations of PCS, IndS, and circulating inflammatory markers have yielded conflicting results.♦ Methods: To clarify this issue, we carried out a prospective observational cohort study in incident PD patients (n = 35; 19 men; mean age: 55 ± 17 years). Midday blood samples were collected and analyzed for total serum PCS, IndS, C-reactive protein, and high-sensitivity interleukin 6. Peritoneal and renal clearances were calculated from urine and dialysate collections, and RRF was calculated as the mean of renal urea nitrogen and creatinine clearances. Patients were assessed 1, 6, 12, and 24 months after PD start. Differences between time points were analyzed using linear mixed models (LMMs).♦ Results: Residual renal function declined significantly over time (LMM p < 0.0001). Peritoneal clearances of both toxins tended to increase, but did not compensate for the declining renal clearances. Serum concentrations of PCS and IndS increased significantly over time (LMM p = 0.01; p = 0.0009). In contrast, total mass removal of both toxins remained stable. Circulating inflammatory markers did not change over time.♦ Conclusions: Our data indicate that serum concentrations of PCS and IndS, but not inflammatory markers, increase in incident PD patients in parallel with loss of RRF.     

Predictors of Mortality and Hospitalization for Cardiac Causes in Patients with Heart Failure and Nonischemic Heart Disease: A Subanalysis of the ALPHA Study

Background: Several studies have searched for predictors of clinical outcome in patients with heart failure (HF). However, since they were collected in clinical trials, most data were subject to selection biases and do not specifically apply to patients with nonischemic heart disease. This study examined the impact of several variables on combined all-cause mortality and hospitalization for cardiac causes, in consecutive ambulatory patients with HF included in the ALPHA registry.
Methods and Results: This analysis included 446 patients with HF and nonischemic heart disease, in New York Heart Association functional class II or III, and a left ventricular (LV) ejection fraction below 40%. In 126 patients (73%) the disease was idiopathic dilated cardiomyopathy, in 72 (16%) hypertensive, in nine (2%) valvular, and in 39 (9%) of other etiologies. The median age was 61 years (range 51–69 years) and 349 (78%) patients were men. Over a median follow-up of 31 months (range 23–40), 82 patients (18%) died or were hospitalized for cardiac causes. In a proportional hazard (Cox) regression model, maximal oxygen consumption (HR 0.9, P = 0.001), LV end-diastolic diameter (HR 1.07, P < 0.001), resting systolic blood pressure (HR 0.97, P < 0.005), and hemoglobin (HR 0.86, P < 0.05) were independent predictors of the combined study endpoint.
Conclusions: In an unselected population of patients with HF and nonischemic heart disease, a reduced exercise capacity, large LV end-diastolic diameter, low systolic blood pressure, and hemoglobin were correlated with long-term all-cause mortality or hospitalization for cardiac causes. These observations may help stratifying and tailoring the treatment of patients with HF and nonischemic heart disease.     

The PRIMAVERA study protocol design: Evaluating the effect of continuous erythropoiesis receptor activator (C.E.R.A.) on renal function in non-anemic patients with chronic kidney disease

Erythropoiesis stimulating agents (ESA) are widely used for hemoglobin correction in patients suffering from renal anemia. However, their beneficial non-hematopoietic effects on renal deterioration have not been adequately assessed. The Primavera study is the first prospective, controlled trial to assess whether ESA treatment could ameliorate progression of chronic kidney disease (CKD) in non-anemic patients. Primavera is a single-blind, 24-month trial in which patients are randomized to placebo or to C.E.R.A., a continuous erythropoietin receptor activator. Patients with type 2 diabetes or who have undergone kidney transplantation are eligible to enter the study if they have CKD stage III (estimated GFR [eGFR] 30–59 mL/min/1.73 m²), urinary albumin to creatinine ratio (UACR) ≥ 50 g/g and ≤ 1500 g/g, or total urine protein ≥ 50 mg/24 h and ≤ 1500 mg/24 h, and hemoglobin 11–14 g/dL. The primary efficacy endpoint is the change in eGFR from baseline to month 24. Secondary efficacy endpoints are the changes in UACR, serum cystatin C and serum creatinine from baseline. Safety endpoints include adverse events and discontinuation due to pre-specified adverse events. An interim analysis will be performed after all patients have completed the first year. The planned sample size is 400 patients (200 type 2 diabetics, 200 transplant recipients) conferring 90% power to detect a prespecified significant difference of 1.5 mL/min/1.73 m² in the annual reduction in eGFR between treatment groups. The results of Primavera are expected in 2013.