Pharmacokinetics and Safety of Ferric Pyrophosphate Citrate in Chinese Subjects with and without Hemodialysis-Dependent Stage 5 Chronic Kidney Disease

BACKGROUND AND OBJECTIVE

Anemia caused by iron depletion is common in patients with hemodialysis-dependent stage 5 chronic kidney disease (CKD-5HD) patients. To maintain the iron levels, external administration of iron is essential. Ferric pyrophosphate citrate (FPC) is a novel, water-soluble complex iron salt. The present study was conducted to evaluate the pharmacokinetic (PK) parameters and safety of FPC in adult healthy Chinese subjects and patients with CKD-5HD.

METHODS

Two open-label, single-center studies were conducted in healthy subjects and patients with CKD-5HD. Healthy subjects received a single intravenous dose of 6.5 mg FPC solution, while CKD-5HD patients were randomized to two different sequences of FPC administration at two sequential hemodialysis (HD) treatments (dose 1 and dose 2). Patients received 27.2 mg of FPC at a dialysate concentration of 95 μg/L for 4 h or a single 6.5 mg dose of FPC administered intravenously via the pre-dialyzer blood circuit. The primary objective was to determine the PK parameters of total serum iron (Fetot), while the secondary objective was the safety of the FPC solution. PK parameters were calculated using Phoenix WinNonlin 8.1 and other parameters were analyzed using SAS 9.4 software. Comparison between HD dose 2 and HD dose 1 was performed using the Wilcoxon rank-sum test and analysis of variance (ANOVA).

RESULTS

A total of 14 healthy subjects with a mean age of 30.8 ± 5.92 years and 12 HD patients with a mean age of 54.3 ± 16.47 years were included. In healthy subjects, the peak serum concentration was reached at the end of infusion of FPC, with an adjusted mean maximum concentration (Cmax,) of 33.46 ± 4.83 μmol/L at a mean time to reach Cmax (Tmax) of 4.09 ± 0.19 h. In patients with CKD-5HD, the adjusted mean Cmax of HD dose 2 was 25.37 ± 4.30 μmol/L at a Tmax, of 3.09 ± 0.32 h, whereas the Cmax, of HD dose 1 was 24.59 ± 4.77 μmol/L at a Tmax, of 3.96 ± 0.26 h. The Fetot concentration-time curves were observed to be similar for both administration methods (HD doses 1 and 2), while the PK parameters differed significantly for Tmax (p = 0.001; baseline correction) and area under the concentration-time curve from time zero to time t (AUCt) [p = 0.031 for cycle variance; without baseline correction] between HD doses 1 and 2. The geometric mean ratios (HD dose 1/HD dose 2) for Cmax and AUCt were within the 85-125% range (Cmax 96.56%; AUCt 96.07%). A total of three and two incidences of adverse events were reported in healthy subjects and patients with CKD-5HD, respectively.

CONCLUSION

FPC showed a good PK and safety profile and hence can be used as maintenance therapy for patients with CKD-5HD by choosing a better method of administration based on clinical feasibility and requirement.

CLINICAL TRIAL REGISTRATION

CTR20181113 and CTR20181119.

Roxadustat promotes osteoblast differentiation and prevents estrogen deficiency-induced bone loss by stabilizing HIF-1α and activating the Wnt/β-catenin signaling pathway

Background

Osteoporosis is a very common skeletal disorder that increases the risk of fractures. However, the treatment of osteoporosis is challenging. Hypoxia-inducible factor-1α (HIF-1α) plays an important role in bone metabolism. Roxadustat is a novel HIF stabilizer, and its effects on bone metabolism remain unknown. This study aimed to investigate the effects of roxadustat on osteoblast differentiation and bone remodeling in an ovariectomized (OVX) rat model.

Methods

In vitro, primary mouse calvarial osteoblasts were treated with roxadustat. Alkaline phosphatase (ALP) activity and extracellular matrix mineralization were assessed. The mRNA and protein expression levels of osteogenic markers were detected. The effects of roxadustat on the HIF-1α and Wnt/β-catenin pathways were evaluated. Furthermore, osteoblast differentiation was assessed again after HIF-1α expression knockdown or inhibition of the Wnt/β-catenin pathway. In vivo, roxadustat was administered orally to OVX rats for 12 weeks. Then, bone histomorphometric analysis was performed. The protein expression levels of the osteogenic markers HIF-1α and β-catenin in bone tissue were detected.

Results

In vitro, roxadustat significantly increased ALP staining intensity, enhanced matrix mineralization and upregulated the expression of osteogenic markers at the mRNA and protein levels in osteoblasts compared with the control group. Roxadustat activated the HIF-1α and Wnt/β-catenin pathways. HIF-1α knockdown or Wnt/β-catenin pathway inhibition significantly attenuated roxadustat-promoted osteoblast differentiation. In vivo, roxadustat administration improved bone microarchitecture deterioration and alleviated bone loss in OVX rats by promoting bone formation and inhibiting bone resorption. Roxadustat upregulated the protein expression levels of the osteogenic markers, HIF-1α and β-catenin in the bone tissue of OVX rats.

Conclusion

Roxadustat promoted osteoblast differentiation and prevented bone loss in OVX rats. The use of roxadustat may be a new promising strategy to treat osteoporosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03162-w.

Thrombocytopenia predicts mortality in Chinese hemodialysis patients- an analysis of the China DOPPS

BACKGROUND

Hemodialysis (HD) patients have a higher mortality rate compared with general population. Our previous study revealed that platelet counts might be a potential risk factor. The role of platelets in HD patients has rarely been studied. The aim of this study is to examine if there is an association of thrombocytopenia (TP) with elevated risk of all-cause mortality and cardiovascular (CV) death in Chinese HD patients.

METHODS

Data from a prospective cohort study, China Dialysis Outcomes and Practice Patterns Study (DOPPS) 5, were analyzed. Demographic data, comorbidities, platelet counts and other lab data, and death records which extracted from the medical record were analyzed. TP was defined as the platelet count below the lower normal limit (< 100*109/L). Associations between platelet counts and all-cause and CV mortality were evaluated using Cox regression models. Stepwise multivariate logistic regression was used to identify the independent associated factors, and subgroup analyses were also carried out.

RESULTS

Of 1369 patients, 11.2% (154) had TP at enrollment. The all-cause mortality rates were 26.0% vs. 13.3% (p < 0.001) in patients with and without TP. TP was associated with higher all-cause mortality after adjusted for covariates (HR:1.73,95%CI:1.11,2.71), but was not associated with CV death after fully adjusted (HR:1.71,95%CI:0.88,3.33). Multivariate logistic regression showed that urine output < 200 ml/day, cerebrovascular disease, hepatitis (B or C), and white blood cells were independent impact factors (P < 0.05). Subgroup analysis found that the effect of TP on all-cause mortality was more prominent in patients with diabetes or hypertension, who on dialysis thrice a week, with lower ALB (< 4 g/dl) or higher hemoglobin, and patients without congestive heart failure, cerebrovascular disease, or hepatitis (P < 0.05).

CONCLUSION

In Chinese HD patients, TP is associated with higher risk of all-cause mortality, but not cardiovascular mortality. Platelet counts may be a useful prognostic marker for clinical outcomes among HD patients, though additional study is needed.

Renal outcomes of idiopathic and atypical membranous nephropathy in adult Chinese patients: a single center retrospective cohort study

BACKGROUND

Membranous nephropathy (MN) is mainly classified into idiopathic MN (iMN) and secondary MN in etiology. In recent years, a new kind of membranous nephropathy, atypical membranous nephropathy (aMN) which shows "full house" in immunofluorescence but without definite etiology was paid more attention. In a single center cohort, the renal outcomes of iMN and aMN were compared.

METHODS

iMN and aMN patients were selected from renal pathology databank from January 2006 to December 2015. Patients' demographics, laboratory values, induction regimens and patients' responses were recorded. Specially, creatinine, eGFR, albumin and 24 h urinary protein excretion were recorded at 6th month after the induction of immunosuppressive (IS) treatment and at the end of follow up. Complete proteinuria remission was defined as urinary protein < 0.3 g/d, partial proteinuria remission was defined as urinary protein between 0.3 g/d ~ 3.5 g/d and decreased > 50 % from the baseline. The primary outcome was worsening renal function, defined as a 30 % or more decrease in eGFR or end-stage renal disease (eGFR < 15ml/min/1.73m²). COX proportional hazard models were used to test if aMN was a risk factor of worsening renal function compared with iMN.

RESULTS

There were 298 patients diagnosed with MN and followed in our center for 1 year or more, including 145 iMN patients with an average follow-up time of 4.5 ± 2.6 years, and 153 aMN patients with 4.1 ± 2.0 years (p = 0.109). The average age of iMN patients was older than aMN patients (56.1 ± 12.2 versus 47.2 ± 16.2 years old, p < 0.001). There were 99 iMN patients and 105 aMN patients with nephrotic range proteinuria and without previous immunosuppressive treatment. 93 (93.9 %) and 95 (90.5 %) patients underwent immunosuppressive treatment in iMN and aMN group, and there was no significant difference of the overall proteinuria remission rates at 6th month (59.1 % vs. 52.0 %, p = 0.334) and endpoint (73.7 % vs. 69.5 %, p = 0.505) between the two groups. 25 (25.3 %) patients in iMN group and 21 (20.0 %) patients in aMN group reached primary endpoint (X² = 0.056, p = 0.812). Multivariate COX regression showed that after demographics, baseline laboratory values and remission status at 6th month were adjusted, aMN group had similar renal outcome compared with iMN group, the HR of primary outcome was 0.735 (95 % CI 0.360 ~ 1.503, p = 0.399).

CONCLUSIONS

The proteinuria remission rates and renal outcomes were similar in iMN and aMN patients after covariables were adjusted.

The Influence of Altitude on Erythropoietin Resistance Index in Maintenance Hemodialysis Patients: Data from Tibetan Plateau

BACKGROUND

It is known that hypoxia influences many of the biologic processes involved in erythropoiesis; therefore, the high-altitude hypoxia may affect erythropoietin (EPO) responsiveness in maintenance hemodialysis (MHD) patients. This study aimed to evaluate the impact of altitude on EPO responsiveness in MHD patients.

METHODS

In this retrospective study, MHD patients from Tibet Autonomous Region People's Hospital (3,650 m above sea level) and Peking University People's Hospital (43.5 m above sea level) were recruited between May 2016 and December 2018. Patients were divided into 2 groups according to altitude. Variables including age, sex, dialysis vintage, dialysis modality, duration of EPO use, EPO doses, and laboratory tests were collected and analyzed. EPO responsiveness was measured in terms of the EPO resistance index (ERI). ERI was defined as the weekly weight-adjusted dose of EPO (IU/kg/week) divided by hemoglobin concentration (g/dL). The association between ERI and altitude was estimated using a multivariable linear regression model.

RESULTS

Sixty-two patients from Tibet Autonomous Region People's Hospital (high-altitude [HA] group) and 102 patients from Peking University People's Hospital (low-altitude [LA] group) were recruited. The ERI for HA group and LA group was 6.9 ± 5.1 IU w-1 kg-1 (g/dL)-1 and 11.5 ± 6.4 IU w-1 kg-1 (g/dL)-1, respectively. After adjusting for covariates by multivariable regression, altitude was independently associated with ERI (R2 = 0.245, p < 0.001).

CONCLUSION

Altitude had an independent negative correlation with ERI. This result supported the hypothesis that altitude-associated hypoxia improved EPO responsiveness in MHD patients.

The effect of BCM guided dry weight assessment on short-term survival in Chinese hemodialysis patients : Primary results of a randomized trial - BOdy COmposition MOnitor (BOCOMO) study

BACKGROUND

Lack of accurate and effective assessment tools of fluid status is one of the major challenges to reach proper dry weight (DW) in chronic hemodialysis (HD) population. The aim of this randomized study was to evaluate the effect of bioimpedance guided DW assessment on long-term outcomes in Chinese HD patients. Eligible patients were randomly assigned (1:1) to two groups in each center, the control group and body composition monitor (BCM) group. In the BCM group, DW has been evaluated by bioimpedance technic every 2 months during follow-up. The primary composite endpoint consisted of death, acute myocardial infarction, cerebral infarction, cerebral hemorrhage, and peripheral vascular disease.

METHODS

A total of 445 patients were recruited from 11 hemodialysis centers from Beijing, Tianjin and Shijiazhuang cities from Jan 1, 2013 to Dec 31, 2014. They were randomized into either BCM group or control group. All patients have been followed up for 1 year or until Dec 31, 2014 or censoring.

RESULTS

At baseline, there were no significant differences between two groups in terms of demographic parameters, dialysis vintage, percentage of vascular access, and comorbid conditions. At the end of the study, 18 (4.04%) patients had died (11 in control group and 7 in BCM group). Kaplan-Meier survival analysis showed no significant difference in survival rates between two groups (log-rank test P = 0.07). However, there was an increasing trend of survival rates in BCM group compared to the control group. In the multivariable Cox analysis, there was a nonsignificant trend toward less primary composite end points in the BCM group in the adjusted analysis, the hazard ratio was impressive (0.487, 95% CI 0.217-1.091, P = 0.08).

CONCLUSION

Bioimpedance technic has been applied to assess fluid status for decades and has been proved to be a promising tool for clinical practice. Although short-term outcomes were not improved in the randomized, controlled trial, the ascending trend in survival has been observed. Further studies are needed to investigate the survival benefit of bioimpedance method in DW assessment in a larger sample with longer follow-up period.

TRIAL REGISTRATION

ClinicalTrials.org, NCT01509937. Registered 13 January 2012.

Protocol for a prospective, cluster randomized trial to evaluate routine and deferred dialysis initiation (RADDI) in Chinese population

BACKGROUND

The timing of when to initiate dialysis for progressive chronic kidney disease (CKD) patients has not been well established. There has been a strong trend for early dialysis initiation for these patients over the past decades. However, the perceived survival advantage of early dialysis has been questioned by a series of recent observational studies. The only randomized controlled trial (RCT) research on this issue found the all-cause mortality, comorbidities, and quality of life showed no difference between early and late dialysis starters. To better understand optimal timing for dialysis initiation, our research will evaluate the efficacy and safety of deferred dialysis initiation in a large Chinese population.

METHODS

The trial adopts a multicenter, cluster randomized, single-blind (outcomes assessor), and endpoint-driven design. Eligible participants are 18-80 years old, in stable CKD stages 4-5 (eGFR > 7 ml/min /1.73 m2), and with good heart function (NYHA grade I or II). Participants will be randomized into a routine or deferred dialysis group. The reference eGFR at initiating dialysis for asymptomatic patients is 7 ml/min /1.73 m2 (routine dialysis group) and 5 ml/min/1.73 m2 or less (deferred dialysis group) in each group. The primary endpoint will be the difference of all-cause mortality and acute nonfatal cerebro-cardiovascular events between the two groups. The secondary outcomes include hospitalization rate and other safety indices. The primary and secondary outcomes will be analyzed by appropriate statistical methods.

DISCUSSION

This study protocol represents a large, cluster randomized study evaluating deferred and routine dialysis intervention for an advanced CKD population. The reference eGFR to initiate dialysis for both treatment groups is targeted at less than 7 ml/min/1.73m2. With this design, we aim to eliminate lead-time and survivor bias and avoid selection bias and confounding factors. We acknowledge that the study has limitations. Even so, given the low-targeted eGFR values of both arms, this study still has potential economic, health, and scientific implications. This research is unique in that such a low targeted eGFR value has never been studied in a clinical trial.

TRIAL REGISTRATION

The trial has been approved by ClinicalTrials.gov (Trial registration ID NCT02423655). The date of registration was April 22, 2015.

Quality of life in caregivers compared with dialysis recipients: The Co-ACTIVE sub-study of the ACTIVE dialysis trial

AIM

To compare quality of life (QOL) of caregivers of dialysis patients with the cared for patients and population norms.

METHODS

The ACTIVE Dialysis study randomized participants to extended (median 24 h/week) or standard (median 12 h/week) haemodialysis hours for 12 months. A subgroup of participants and their nominated caregivers completed QOL questionnaires including the EuroQOL-5 Dimension-3 Level (EQ5D-3 L), short form-36 (SF-36, also allowing estimation of the SF-6D), as well as a bespoke questionnaire and the personal wellbeing index (PWI). Caregiver QOL was compared with dialysis patient QOL and predictors of caregiver QOL were determined using multivariable regression.

RESULTS

There were 54 patients and caregiver pairs, predominantly from China. Caregivers mean (SD) age was 53.4 (11.3) years, 60% were female, 71% cared for their spouse/partner, and 36% were educated to university level. Caregivers had better physical but similar mental QOL compared with dialysis patients (mean SF-36 physical component summary: 46.9 ± 8.7 vs 40.4 ± 10.2, P < 0.001; mental component summary: 47.8 ± 9.7 vs 49.6 ± 12.0, P = 0.84). Health utility measured with EQ5D-3 L was not significantly different between caregivers and dialysis patients (mean 0.869 ± 0.185 vs 0.798 ± 0.227, P = 0.083). Caregiver PWI was 43.7 ± 15.5, significantly lower than the Chinese population norm (68.2 ± 14.2, P < 0.001). Higher physical and mental QOL among caregivers was predicted by university education but not age, gender or daily hours caring.

CONCLUSION

Caregivers have higher physical and equivalent mental QOL to dialysis patients but poorer personal well-being than the Chinese population. University education predicts better QOL and may be a surrogate for socioeconomic or other factors. (NCT00649298).

Preventative effects of metformin on glucocorticoid-induced osteoporosis in rats

This study evaluated the preventative effects of metformin (Met) on glucocorticoid (GC)-induced osteoporosis in a rat model, compared with alendronate (Aln). Twenty-eight 3-month-old female Sprague-Dawley rats were randomly assigned into four groups: normal control (Ctr), methylprednisolone (MP, 13 mg/kg/day, sc, 5 days per week), MP plus Aln orally (1 mg/kg/day), and MP plus Met orally (200 mg/kg/day). After 9 weeks, serum bone metabolic biochemistry, bone densitometry and histomorphometry were performed. The GC-induced osteoporosis model was characterized by decreased osteocalcin, increased tartrate-resistant acid phosphatase-5b (TRAP-5b), and decreased bone mineral density (BMD) in the femur and fifth lumbar vertebra (L5). Histomorphometrically, MP significantly decreased trabecular bone volume, decreased bone formation and increased bone resorption in proximal metaphysis, compared with the controls. Aln and Met increased the BMDs of femur (0.305 ± 0.011 vs. 0.280 ± 0.012, P < 0.05; 0.304 ± 0.019 vs. 0.280 ± 0.012, P < 0.05) and L5 (0.399 ± 0.029 vs. 0.358 ± 0.022, P < 0.05; 0.397 ± 0.022 vs. 0.358 ± 0.022, P < 0.05), compared with the model group. Met increased osteocalcin and decreased TRAP-5b, but Aln only decreased TRAP-5b, compared with model group. In histomorphometry of tibial proximal metaphysis, Aln and Met increased trabecular bone volume (39.21 ± 2.46 vs. 30.98 ± 5.83, P < 0.05; 38.97 ± 5.56 vs. 30.98 ± 5.83, P < 0.05), while Met increased the bone formation dynamic parameters and decreased bone resorption dynamic parameters, but Aln just decreased bone resorption dynamic parameters, compared with model group significantly. These findings suggest that metformin prevents GC-induced bone loss by suppressing bone resorption and stimulating bone formation in trabecular bone. The action mode of metformin was different from alendronate, which only suppressed bone resorption.

Rituximab treatment for immune-complex-mediated membranoproliferative glomerulonephritis

Immune-complex-mediated membranoproliferative glomerulonephritis (MPGN) is a new concept that refers to MPGN with immunoglobulin and C3 deposition in the kidney based on immunofluorescence examination. It is associated with pathological autoantibodies production. Rituximab, as an immunosuppressive agent, can eliminate B cells selectively. We reported a case that a patient with immune-complex-mediated MPGN and HCV infection, but no cryoglobulinemia, responded well to the treatment of low-dosage of rituximab and steroids. His proteinuria decreased remarkably with the serum creatinine and liver function remaining stable within 1 year. His favorable outcome suggests that low-dosage of rituximab in conjunction with steroids is an effective and safe treatment choice for immune-complex-mediated MPGN.

Effect of extended hours dialysis on markers of chronic kidney disease-mineral and bone disorder in the ACTIVE Dialysis study

Background

Chronic Kidney Disease - Mineral and Bone Disorder (CKD-MBD) is a significant cause of morbidity among haemodialysis patients and is associated with pathological changes in phosphate, calcium and parathyroid hormone (PTH). In the ACTIVE Dialysis study, extended hours dialysis reduced serum phosphate but did not cause important changes in PTH or serum calcium. This secondary analysis aimed to determine if changes in associated therapies may have influenced these findings and to identify differences between patient subgroups.

Methods

The ACTIVE Dialysis study randomised 200 participants to extended hours haemodialysis (≥24 h/week) or conventional haemodialysis (≤18 h/week) for 12 months. Mean differences between treatment arms in serum phosphate, calcium and PTH; and among key subgroups (high vs. low baseline phosphate/PTH, region, time on dialysis, dialysis setting and frequency) were examined using mixed linear regression.

Results

Phosphate binder use was reduced with extended hours (− 0.83 tablets per day [95% CI -1.61, − 0.04; p = 0.04]), but no differences in type of phosphate binder, use of vitamin D, dose of cinacalcet or dialysate calcium were observed. In adjusted analysis, extended hours were associated with lower phosphate (− 0.219 mmol/L [− 0.314, − 0.124; P < 0.001]), higher calcium (0.046 mmol/L [0.007, 0.086; P = 0.021]) and no change in PTH (0.025 pmol/L [− 0.107, 0.157; P = 0.713]). The reduction in phosphate with extended hours was greater in those with higher baseline PTH and dialysing at home.

Conclusion

Extended hours haemodialysis independently reduced serum phosphate levels with minimal change in serum calcium and PTH levels. With a few exceptions, these results were consistent across patient subgroups.

Trial registration

Clinicaltrials.gov NCT00649298. Registered 1 April 2008.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1438-3) contains supplementary material, which is available to authorized users.

Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

BACKGROUND

Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes.

METHODS

We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18-85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR) 25-75 mL/min per 1·73 m² of body surface area, and a urine albumin-to-creatinine ratio (UACR) of 300-5000 mg/g who had received maximum labelled or tolerated renin-angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders) were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days) or end-stage kidney disease (eGFR <15 mL/min per 1·73 m² sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure) in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532.

FINDINGS

Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325) or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4-2·9). 79 (6·0%) of 1325 patients in the atrasentan group and 105 (7·9%) of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR] 0·65 [95% CI 0·49-0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%) of 1325 patients in the atrasentan group and 34 (2·6%) of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85-2·07]; p=0·208). 58 (4·4%) patients in the atrasentan group and 52 (3·9%) in the placebo group died (HR 1·09 [95% CI 0·75-1·59]; p=0·65).

INTERPRETATION

Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease.

FUNDING

AbbVie.

Study on the Prevalence of Vascular Calcification in Different Types of Arteries and Influencing Factors in Maintenance Peritoneal Dialysis Patients

OBJECTIVE

To investigate the occurrence of vascular calcification (VC) in different types of arteries in patients with maintenance peritoneal dialysis (PD) patients and its influencing factors.

METHODS

This study enrolled PD patients with stable status who has received PD treatment for more than 6 months in Peking University People's Hospital. We used plain X-ray films of abdomen, pelvis, and hands to quantitatively evaluate VC of large artery (abdominal aorta, iliac artery), medium artery (femoral artery, radial artery), and small artery (finger arteries). Two radiologists read and scored radiographs blindly. Demographic data, clinical characteristics, Charlson comorbidity index (CCI), baseline and time-average laboratory indices including parameters of calcium phosphorus metabolism, serum albumin, PD adequacy were collected. A logistic regression model was used to estimate the influencing factors of different sites of VC.

RESULTS

(1) 154 PD patients were enrolled in this study: seventy-eight males, mean age was 60.4 ± 13.9 years, and median PD duration was 24 (16.39) months. The major primary disease was diabetic nephropathy (39%). (2) Among the 154 PD patients, the proportion of calcification of large artery was the highest (found in 100 patients, accounting for 64.9%); then the medium artery (66, 42.9%); and 15 of small artery, accounting for 9.7%. (3) Logistic regression showed that older age, longer dialysis duration, lower baseline serum intact parathyroid hormone (iPTH), and higher CCI scores were independent risk factors of large artery calcification (p < 0.05), and higher CCI scores, higher baseline serum triglycerides (TG), lower baseline serum iPTH, and time-average iPTH were independent risk factors of medium and small arteries.

CONCLUSIONS

In PD patients, the occurrence of large artery calcification was higher than others. Among different sites of VC, the abdominal aortic calcification was most likely to occur, and the proportion of small artery calcification was low. Calcification of medium and small arteries can exist alone without calcification of large artery. Large artery calcification was more likely to occur in patients with older age, longer dialysis duration, lower baseline serum iPTH levels and higher CCI scores. Patients with higher CCI scores, higher baseline TG and lower baseline iPTH, and time-average iPTH were more likely to develop small and medium artery calcification.

Implementing core outcomes in kidney disease: report of the Standardized Outcomes in Nephrology (SONG) implementation workshop

There are an estimated 14,000 randomized trials published in chronic kidney disease. The most frequently reported outcomes are biochemical endpoints, rather than clinical and patient-reported outcomes including cardiovascular disease, mortality, and quality of life. While many trials have focused on optimizing kidney health, the heterogeneity and uncertain relevance of outcomes reported across trials may limit their policy and practice impact. The international Standardized Outcomes in Nephrology (SONG) Initiative was formed to identify core outcomes that are critically important to patients and health professionals, to be reported consistently across trials. We convened a SONG Implementation Workshop to discuss the implementation of core outcomes. Eighty-two patients/caregivers and health professionals participated in plenary and breakout discussions. In this report, we summarize the findings of the workshop in two main themes: socializing the concept of core outcomes, and demonstrating feasibility and usability. We outline implementation strategies and pathways to be established through partnership with stakeholders, which may bolster acceptance and reporting of core outcomes in trials, and encourage their use by end-users such as guideline producers and policymakers to help improve patient-important outcomes.

Abdominal aortic calcification can predict all-cause mortality and CV events in dialysis patients: A systematic review and meta-analysis

BACKGROUND

Abdominal aortic calcification (AAC) has a pretty high incidence in dialysis patients and may be associated with their prognosis. AAC can be assessed by abdominal CT or X-ray. We determined to investigate whether the occurrence of AAC is associated with all-cause mortality and cardiovascular (CV) events in dialysis patients through this meta-analysis and systematic review.

METHODS

A comprehensive literature search was conducted using the PubMed, Cochrane library, Embase, Medline databases to collect cohort studies investigating whether AAC is associated with all-cause mortality and CV events of patients, and we also searched gray articles and conferences abstracts. Meta-analysis was performed by STATA software. Pooled results were expressed as hazard ratio (HR) with corresponding 95% confidence intervals (CI). Fixed-effect models were used to pool the HR of each trial.

RESULTS

10 studies (2,724 dialysis patients) were identified. The presence of AAC was associated with increased risk for all-cause mortality among dialysis patients (HR, 2.84; 95% CI, 2.03-3.98; I2 = 9.8%; P = 0.354). Meanwhile, there was an association between AAC and increased risk for all CV events (fatal and non-fatal) in patients (HR, 2.04; 95% CI, 1.51-2.76, I2 = 44.6%; P = 0.125). 3 studies presented their endpoint as CV mortality, and the pooled HR was 2.46 (95%CI 1.38-4.40; I2 = 0.0%; P = 0.952). There were also 2 studies that reported their primary endpoint as all-cause mortality and CV events, and the pooled HR was 5.72 (95% CI 3.24-10.10; I2 = 0.0%; P = 0.453).

CONCLUSIONS

Among patients treated with dialysis, AAC is associated with adverse outcomes, including all-cause mortality and CV events (fatal and non-fatal). The abdominal X-ray or CT scan can be used as a useful added method to evaluate the patient's calcification. This may provide reasonable data for estimating the risk of adverse events in dialysis patients, which is helpful in guiding clinical treatment and improving the prognosis of dialysis patients.

[Peritoneal dialysis-related eosinophilic peritonitis: a case report and literature review]

Peritoneal dialysis (PD)-related peritonitis is recognized as a common complication of peritoneal dialysis. Eosinophilic peritonitis is a rare type of non-infection PD-related peritonitis. Eosinophilic peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients was first reported in 1967. The cause of eosinophilic peritonitis is obscure, however it may be related to some etiologies: (1) hypersensitivity to PD materials, including catheter or dialysate; (2) bacteria, fungal or mycobacterium tuberculosis infection. Clinical investigations include asymptomatic cloudy PD effluent, fever, abdominal pain and eosinophil count elevate in PD effluent. Eosinophilic peritonitis is usually mild and self-limited. With the development of PD, more eosinophilic peritonitis cases and researches were reported. Here, we report a patient on CAPD with eosinophilic peritonitis. A 71-year-old female patient developed end-stage renal disease for 4 years and underwent CAPD (2 000 mL of 1.5% dialysis solution with four exchanges daily) for 5 months. With a history of unclean food, she was hospitalized for complaints of diarrhea, fever and cloudy peritoneal effluent for 10 days. Dialysis effluent showed an elevated white blood cell (WBC) count of 1 980 cell/mm³, with 60% polymorphonuclear cells. She was diagnosed as PD-related peritonitis, and therapy was initiated with intraperitoneal ceftazidime 1 g once a day and vancomycin 500 mg every other day. She was admitted to the hospital as the symptoms were not relieved. Her peripheral blood cell count showed a total WBC count of 6 940 cells/mm³, 36.8% eosinophil. Her PD effluent analysis showed turbidity, total WBC count of 1 480 cells/mm³, and 83% polymorphonuclear cells. Her dialysate bacteria culture, fungus culture, polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR), acid-fast stain were all negative. On admission day 4, the treatments were changed to levofloxacin 200 mg once a day and vancomycin 500 mg every other day. After two weeks of antibiotics treatment, patient's symptoms were not completely improved and her dialysis effluent remained cloudy. Her blood eosinophil count elevated to 36.8%，eosinophil proportion in PD effluent>90% and PD effluent pathological findings showed eosinophil>90%. Eosinophilic peritonitis was diagnosed and a decision was made to give loratadine daily dose of 10 mg orally. The possible reasons might be the patient's allergy to some components of PD solution or connection systems in the beginning of PD, and this bacterial peritonitis episode, as well as the application of vancomycin, might lead to the fact that eosinophilic peritonitis acutely developed. For there was no improvement in clinical symptoms, loratadine was stopped, and the patient was discharged 18 days later, and received follow-up closely. Two months later, eosinophil count in blood and PD fluid decreased to normal range with no symptom. This case reminds us that in any PD-related peritonitis patient with prolonged symptoms after appropriate antibiotic therapy, and typical clinical symptoms, the diagnosis of eosinophilic peritonitis should be considered. For the count and percentage of eosinophils are not routinely reported in most laboratories, doctors need to contact the department of laboratory and the department of pathology, to confirm the cell count and proportion of eosinophils in dialysis effluent, so as to make the definite diagnosis, which can not only avoid antibiotics overuse, but also avoid antibiotics-induced eosinophilic peritonitis (such as vancomycin).

Clinicopathological features of atypical membranous nephropathy with unknown etiology in adult Chinese patients

Membranous nephropathy is typically classified as idiopathic and secondary, but nowadays the number of atypical membranous nephropathy (aMN) is increasing, many of which cannot determine its etiology in China. In this study, we compared the clinical and pathological characteristics of idiopathic membranous nephropathy (iMN) with aMN with unknown etiology from a single center in China.We retrospectively reviewed the clinical data of 577 patients with iMN and aMN at Peking University People's Hospital from January 2006 to December 2015 over a 10-year period, and analyzed their clinical and pathological characteristics. The level of serum phospholipase A2 receptors (PLA2R) antibody was detected in 106 iMN and 162 aMN patients.There were 278 iMN patients and 299 aMN patients who were included into this study in 3210 cases of renal biopsy during a 10-year period in our hospital. The average age of patients with iMN was significantly older than those with aMN (54.77 ± 13.01 vs 47.13 ± 16.16, P < .001). Around 75 patients (27%) were smokers in iMN patients, and 111 patients (37.1%) in aMN patients (P = .009). The mainly clinical manifestation of these 2 groups was nephrotic syndrome (61.5% in iMN group vs 58.4% in aMN group), but there were more patients accompanied with nephritis syndrome in aMN group than iMN group (17.1% vs 6.1%, P < .001). The immunofluorescence of renal biopsy showed "full house" in aMN group; and IgG subclass of the glomeruli demonstrated IgG4 (90.4%) was commonest in iMN group, but IgG1 (94.6%) in aMN group. 51 (48.1%) patients with iMN were detected positive PLA2R antibody in their serum, and 93 (57.4%) in aMN patients (P = .168). The patients with positive PLA2R antibody had higher positive rate of microscopic hematuria and urinary protein, lower albumin.The aMN patients are younger, higher smoking rate, its main clinical manifestation is nephrotic syndrome, but more of them accompanied with nephritis syndrome than those in iMN patients. Serum PLA2R antibody could not distinguish aMN from iMN. aMN could be a special glomerular disease in China, and need a further research on a larger scale.

Accuracy of iohexol plasma clearance for GFR-determination: a comparison between single and dual sampling

Background

Current guidelines regarding plasma-sampling techniques for glomerular filtration rate (GFR) determination are inconsistent. Single-sample methods are commonly believed not to be precise enough to meet clinical demands. The present study compared the agreement between single- and dual- plasma sampling methods with a three-point plasma clearance of iohexol.

Methods

A total of 46 healthy volunteers and 124 chronic kidney disease (CKD) patients with varying degrees of renal dysfunction received 5 ml iohexol (300 mgI/ml) i.v. and plasma samples were drawn at 2-, 3- and 4-h post-injection. Plasma-iodine concentrations were detected by high-performance liquid chromatography (HPLC).

Results

Bias was similar among single-plasma sampling methods (SPSM) and dual-plasma sampling methods (DPSM). The best correlation was obtained from the 2- and 4-h DPSM (concordance correlation coefficient [CCC]: 0.9988) with none of the estimates differed by more than 30% from the reference GFR and only one (0.06%) estimate differed by more than 10% (P₃₀, 100%; P₁₀, 99.4%). SPSM using samples around 3- or 4-h demonstrated acceptable accuracy at a GFR level of ≥60 ml/min/1.73m² (P₃₀ = 100% and P₁₀ > 75% for both measurements).

Conclusion

4-h SPSM is advantageous in clinical practice in subjects with GFR ≥ 60 ml/min/1.73m². For patients with an expected GFR < 60 ml/min/1.73m², a prolonged sampling time is more reliable.

Twice-Weekly Hemodialysis and Clinical Outcomes in the China Dialysis Outcomes and Practice Patterns Study

INTRODUCTION

In China, a quarter of patients are undergoing 2-times weekly hemodialysis. Using data from the China Dialysis Outcomes and Practice Patterns Study (DOPPS), we tested the hypothesis that whereas survival and hospitalizations would be similar in the presence of residual kidney function (RKF), patients without RKF would fare worse on 2-times weekly hemodialysis.

METHODS

In our cohort derived from 15 units randomly selected from each of 3 major cities (total N = 45), we generated a propensity score for the probability of dialysis frequency assignment, estimated a survival function by propensity score quintiles, and averaged stratum-specific survival functions to generate mean survival time. We used the proportional rates model to assess hospitalizations. We stratified all analyses by RKF, as reported by patients (urine output <1 vs. ≥1 cup/day).

RESULTS

Among 1265 patients, 123 and 133 were undergoing 2-times weekly hemodialysis with and without evidence of RKF. Over 2.5 years, adjusted mean survival times were similar for 2- versus 3-times weekly dialysis groups: 2.20 versus 2.23 and 2.20 versus 2.15 for patients with and without RKF (P = 0.65). Hazard ratios for hospitalization rates were similar for 2- versus 3-times weekly groups, with (1.15, 95% confidence interval = 0.66-2.00) and without (1.10, 95% confidence interval 0.68-1.79]) RKF. The normalized protein catabolic rate was lower and intradialytic weight gain was not substantially higher in the 2- versus 3-times weekly dialysis group, suggesting greater restriction of dietary sodium and protein.

CONCLUSION

In our study of patients in China's major cities, we could not detect differences in survival and hospitalization for those undergoing 2- versus 3-times weekly dialysis, regardless of RKF. Our findings indicate the need for pragmatic studies regarding less frequent dialysis with associated nutritional management.

Report of the Standardized Outcomes in Nephrology-Hemodialysis (SONG-HD) Consensus Workshop on Establishing a Core Outcome Measure for Hemodialysis Vascular Access

Vascular access outcomes in hemodialysis are critically important for patients and clinicians, but frequently are neither patient relevant nor measured consistently in randomized trials. A Standardized Outcomes in Nephrology-Hemodialysis (SONG-HD) consensus workshop was convened to discuss the development of a core outcome measure for vascular access. 13 patients/caregivers and 46 professionals (clinicians, policy makers, industry representatives, and researchers) attended. Participants advocated for vascular access function to be a core outcome based on the broad applicability of function regardless of access type, involvement of a multidisciplinary team in achieving a functioning access, and the impact of access function on quality of life, survival, and other access-related outcomes. A core outcome measure for vascular access required demonstrable feasibility for implementation across different clinical and trial settings. Participants advocated for a practical and flexible outcome measure with a simple actionable definition. Integrating patients' values and preferences was warranted to enhance the relevance of the measure. Proposed outcome measures for function included "uninterrupted use of the access without the need for interventions" and "ability to receive prescribed dialysis," but not "access blood flow," which was deemed too expensive and unreliable. These recommendations will inform the definition and implementation of a core outcome measure for vascular access function in hemodialysis trials.

Early mortality risk in incident Chinese hemodialysis patients: a retrospective cohort study

Background: Early mortality risk of maintenance hemodialysis (MHD) patients varies by country and ethnicity. Here, early mortality in incident Chinese HD patients were studied.

Methods: Data from 1 January 2007 to 31 December 2013 were pulled from Beijing dialysis registry system. All included patients were followed to the end of 2013. This time period of dialysis was divided into six intervals (≤120, 121–365 days; 1–2, 2–3, 3–4, ≥5 years). Patients’ demographics, primary cause of end-stage renal disease (ESRD), date of first HD, date of death, cause for death, date and cause of censoring were extracted from the registry database. All-cause mortality (per 100 patient-years) was calculated for each period stratified by sex, age and cause of ESRD. Monthly mortality rates were also calculated.

Results: A total of 11,955 patients were included, 6738 were males and 5217 were females. The mean age at dialysis initiation was 57.7 ± 16.1 years. The median follow-up time was 19.8 months. There were total 2555 deaths. The overall mortality rate was 8.2 per 100 patient-years. Mortality rates were 18.7, 7.5, 6.9, 6.9, 6.5 and 6.2 in each period. The first 2 months mortality rates were 41.9 and 16.6 per 100 patient-years. Higher mortality was observed in patients who were older, female, diabetic and hypertensive.

Conclusions: The most critical period was the first 2 months of dialysis initiation. Patients who were older, female, diabetic and hypertensive had higher risk of early mortality. Our analysis highlighted that the transitional period from sever CKD stages to dialysis initiation, when optimal supportive care should be adopted, was crucial for patients’ survival.

A case report of POEMS syndrome with renal involvement as immunotactoid glomerulopathy

RATIONALE

POEMS syndrome is a rare multi-system disorder, which sometimes involves the kidney. Immunotactoid glomerulopathy (ITG) is an uncommon glomerular disease resulted from deposits of immunoglobulins and its derivatives. ITG caused by POEMS syndrome is rarely reported.

PATIENT CONCERNS

A 63-year-old man was presented with acute kidney injury. In addition, it's found that he had abnormal serum free κ /λ ratio, polyneuropathy, Castleman's disease, organomegaly, endocrinopathy and skin changes.

DIAGNOSES

POEMS syndrome was diagnosed, Renal biopsy revealed an ITG.

INTERVENTIONS

Dexamethasone and thalidomide were given, as well as hemodialysis and other supportive treatments.

OUTCOMES

The patient's extrarenal manifestations improved gradually and his renal function also showed slight improvement.

LESSONS

ITG caused by POEMS syndrome is rare, however, it makes sense that the monoclonal proteins produced by the plasma cells could cause ITG. Chemotherapy similar to that employed in multiple myeloma may be beneficial for these patients.

Effect of extended hours dialysis on sleep quality in a randomized trial

AIM

Poor sleep quality is common in haemodialysis patients and associated with worse outcomes. In this pre-specified analysis, we examined the impact of extended hours haemodialysis on sleep quality.

METHODS

The ACTIVE Dialysis trial randomized 200 participants to extended (≥24 h/week) or standard (target 12-15 h) hours haemodialysis over 12 months. Sleep quality was measured in the Kidney Disease Quality of Life Short Form 1.3 (KDQOL-SF) by overall sleep quality score (0-10, 10 = 'very good') and the sleep subscale (0-100, 100 = 'best possible sleep') every 3 months via blinded telephone interview. The average intervention effect was calculated by mixed linear regression adjusted by time point and baseline score. Factors predicting sleep quality were assessed by multivariate regression analysis.

RESULTS

Overall sleep quality score and sleep subscale at baseline were similar in both groups (5.9 [95%CI 5.4-6.4] vs. 6.3 [5.9-6.8]; 65.0 [60.9-69.1] vs. 63.2 [59.1-67.3]; extended and standard hours, respectively). Extended hours haemodialysis led to a non-significant improvement in overall sleep quality score (average intervention effect 0.44 (-0.01 to 0.89), P = 0.053) and sleep subscale (average intervention effect 3.58 (-0.02 to 7.18), P = 0.051). Poor sleep quality was associated with being female and with current smoking. Sleep quality was positively associated with EuroQol-5D (EQ5D) and the SF-36 Physical Component and Mental Component Summary Scores but not with hospitalizations.

CONCLUSION

Sleep quality was not significantly improved by extended hours dialysis in this study. Sleep quality is positively correlated with quality of life in haemodialysis patients and is poorer in women and current smokers.

Glomerular Filtration Rates in Asians

The National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines recommended the Modification of Diet in Renal Disease study equation for estimating glomerular filtration rate (GFR) for the classification of CKD, but its accuracy was limited to North American patients with estimated GFR <60 mL/min per 1.73 m² body surface area of European (White) or African (Black) descent. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) developed another equation for estimating GFR, derived from a population that included both participants without kidney disease and with CKD. But many ethnicities were inadequately represented. The International Society of Nephrology, Kidney Disease Improving Global Outcomes committee promulgated clinical practice guidelines, which recommended the CKD-EPI equation. Investigators in Asia subsequently assessed the performance of these GFR estimating equations-the Modification of Diet in Renal Disease study equation, the CKD-EPI equation (creatinine only), and the CKD-EPI equations (creatinine and cystatin C). In this review, we summarize the studies performed in Asia on validating or establishing new Asian ethnicity GFR estimating equations. We included both prospective and retrospective studies which used serum markers traceable to reference materials and focused the review of the performance of GFR estimation by comparisons with the GFR estimations obtained from the CKD-EPI equations.

Serum Magnesium Abnormality and Influencing Factors of Serum Magnesium Level in Peritoneal Dialysis Patients: A Single-Center Study in Northern China

Background/Aims: Both hypomagnesemia and hypermagnesemia have been associated with cardiovascular diseases, bone diseases, and mortality in dialysis patients. We aimed to investigate the prevalence of and influencing factors for abnormal serum Mg levels in patients on peritoneal dialysis (PD). Methods: A cross-sectional study in Peking University People’s Hospital recorded the demographic information, clinical characteristics, and laboratory data. Data were assessed and compared with the results from 2 other studies in China. Results: Of 180 enrolled PD patients, the primary diseases were glomerulonephritis (38.3%) and diabetic nephropathy (38.3%). Mean serum Mg concentration was 1.02 ± 0.16 mmol/L; 67% had normal serum Mg concentrations, and 33% had hypermagnesemia. Conclusions: Hypermagnesemia is likely to occur in patients with higher serum phosphate, lower intact parathyroid hormone, and lower high-sensitivity C-reactive protein levels. Serum Mg level distributions in PD patients vary throughout China, may have different potential causes (such as geographical location and dietary habits) and should be further studied.

Vascular Access Outcomes Reported in Maintenance Hemodialysis Trials: A Systematic Review

BACKGROUND

Many randomized controlled trials have been performed with the goal of improving outcomes related to hemodialysis vascular access. If the reported outcomes are relevant and measured consistently to allow comparison of interventions across trials, such trials can inform decision making. This study aimed to assess the scope and consistency of vascular access outcomes reported in contemporary hemodialysis trials.

STUDY DESIGN

Systematic review.

SETTING & POPULATION

Adults requiring maintenance hemodialysis.

SELECTION CRITERIA

All randomized controlled trials and trial protocols reporting vascular access outcomes identified from ClinicalTrials.gov, Embase, MEDLINE, and the Cochrane Kidney and Transplant Specialized Register from January 2011 to June 2016.

INTERVENTIONS

Any hemodialysis-related intervention.

OUTCOMES

The frequency and characteristics of vascular access outcome measures were analyzed and classified.

RESULTS

From 168 relevant trials, 1,426 access-related outcome measures were extracted and classified into 23 different outcomes. The 3 most common outcomes were function (136 [81%] trials), infection (63 [38%]), and maturation (31 [18%]). Function was measured in 489 different ways, but most frequently reported as "mean access blood flow (mL/min)" (37 [27%] trials) and "number of thromboses" (30 [22%]). Infection was assessed in 136 different ways, with "number of access-related infections" being the most common measure. Maturation was assessed in 44 different ways at 15 different time points and most commonly characterized by vein diameter and blood flow. Patient-reported outcomes, including pain (19 [11%]) and quality of life (5 [3%]), were reported infrequently. Only a minority of trials used previously standardized outcome definitions.

LIMITATIONS

Restricted sampling frame for feasibility and focus on contemporary trials.

CONCLUSIONS

The reporting of access outcomes in hemodialysis trials is very heterogeneous, with limited patient-reported outcomes and infrequent use of standardized outcome measures. Efforts to standardize outcome reporting for vascular access are critical to optimizing the comparability, reliability, and value of trial evidence to improve outcomes for patients requiring hemodialysis.

Phase 2 studies of oral hypoxia-inducible factor prolyl hydroxylase inhibitor FG-4592 for treatment of anemia in China

BACKGROUND

FG-4592 (roxadustat) is an oral hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor (HIF-PHI) promoting coordinated erythropoiesis through the transcription factor HIF. Two Phase 2 studies were conducted in China to explore the safety and efficacy of FG-4592 (USAN name: roxadustat, CDAN name: ), a HIF-PHI, in patients with anemia of chronic kidney disease (CKD), both patients who were dialysis-dependent (DD) and patients who were not dialysis-dependent (NDD).

METHODS

In the NDD study, 91 participants were randomized to low (1.1-1.75 mg/kg) or high (1.50-2.25 mg/kg) FG-4592 starting doses or to placebo. In the DD study, 87 were enrolled to low (1.1-1.8 mg/kg), medium (1.5-2.3 mg/kg) and high (1.7-2.3 mg/kg) starting FG-4592 doses or to continuation of epoetin alfa. In both studies, only oral iron supplementation was allowed.

RESULTS

In the NDD study, hemoglobin (Hb) increase ≥1 g/dL from baseline was achieved in 80.0% of subjects in the low-dose cohort and 87.1% in the high-dose cohort, versus 23.3% in the placebo arm (P < 0.0001, both). In the DD study, 59.1%, 88.9% (P = 0.008) and 100% (P = 0.0003) of the low-, medium- and high-dose subjects maintained their Hb levels after 5- and 6-weeks versus 50% of the epoetin alfa-treated subjects. In both studies, significant reductions in cholesterol were noted in FG-4592-treated subjects, with stability or increases in serum iron, total iron-binding capacity (TIBC) and transferrin (without intravenous iron administration). In the NDD study, hepcidin levels were significantly reduced across all FG-4592-treated arms as compared with no change in the placebo arm. In the DD study, hepcidin levels were also reduced in a statistically significant dose-dependent manner in the highest dose group as compared with the epoetin alfa-treated group. Adverse events were similar for FG-4592-treated and control subjects.

CONCLUSIONS

FG-4592 may prove an effective alternative for managing anemia of CKD. It is currently being investigated in a pivotal global Phase 3 program.

A Trial of Extending Hemodialysis Hours and Quality of Life

The relationship between increased hemodialysis hours and patient outcomes remains unclear. We randomized (1:1) 200 adult recipients of standard maintenance hemodialysis from in-center and home-based hemodialysis programs to extended weekly (≥24 hours) or standard (target 12-15 hours, maximum 18 hours) hemodialysis hours for 12 months. The primary outcome was change in quality of life from baseline assessed by the EuroQol 5 dimension instrument (3 level) (EQ-5D). Secondary outcomes included medication usage, clinical laboratory values, vascular access events, and change in left ventricular mass index. At 12 months, median weekly hemodialysis hours were 24.0 (interquartile range, 23.6-24.0) and 12.0 (interquartile range, 12.0-16.0) in the extended and standard groups, respectively. Change in EQ-5D score at study end did not differ between groups (mean difference, 0.04 [95% confidence interval, -0.03 to 0.11]; P=0.29). Extended hours were associated with lower phosphate and potassium levels and higher hemoglobin levels. Blood pressure (BP) did not differ between groups at study end. Extended hours were associated with fewer BP-lowering agents and phosphate-binding medications, but were not associated with erythropoietin dosing. In a substudy with 95 patients, we detected no difference between groups in left ventricular mass index (mean difference, -6.0 [95% confidence interval, -14.8 to 2.7] g/m²; P=0.18). Five deaths occurred in the extended group and two in the standard group (P=0.44); two participants in each group withdrew consent. Similar numbers of patients experienced vascular access events in the two groups. Thus, extending weekly hemodialysis hours did not alter overall EQ-5D quality of life score, but was associated with improvement in some laboratory parameters and reductions in medication burden. (Clinicaltrials.gov identifier: NCT00649298).

Twice-Weekly Hemodialysis in China: Can It Be A Better Option for Initiation or Maintenance Dialysis Therapy?

Cumulative evidence indicates it may be worthwhile revisiting the twice-weekly hemodialysis (HD) regimen as a valid option for individualized or incremental treatments for selected patients with end-stage renal disease. In this article, we will review the current evidences on the potential pros and cons of twice-weekly HD compared to thrice-weekly HD including China's experience in the practice of twice-weekly HD. A prudent patient selection and close dialysis adequacy monitoring might be necessary for this medical treatment choice. More randomized prospective controlled studies for the critical evaluation of twice-weekly dialysis are encouraged.

Current burden of end-stage kidney disease and its future trend in China

INTRODUCTION

Understanding the status and trends of patients with ESKD is important to evaluate and predict its impact on the health care system in China.

METHODS

Available publications and/or presentations from national and regional dialysis and transplantation registries were collected.

RESULTS AND DISCUSSION

A national report in 1999 revealed that the prevalence and incidence of dialysis in China were 33.2 per million population (pmp) and 15.3 pmp, respectively. The numbers were updated to 237.3 pmp and 15.4 pmp in 2012. In big cities like Beijing and Shanghai, the numbers are much higher, with prevalence and incidence of 524.6 pmp and 107.3 pmp in Beijing in 2011, and 544.7 pmp and 82.9 pmp in Shanghai in 2011, respectively. The majority of patients received hemodialysis, accounting for 89.5% in 1999 and 89.1% in 2012. The increased prevalence of dialysis is partly due to increased affordability of dialysis; while affordability and accessibility still limit renal replacement therapy in China. Regarding causes of end-stage kidney disease in China, about half of the patients are diagnosed glomerulonephritis. The surge of hypertension and diabetes during the 1990s will probably have profound effects on prevalence and etiology of kidney disease in China.

Association of CKD-MBD Markers with All-Cause Mortality in Prevalent Hemodialysis Patients: A Cohort Study in Beijing

The relationships between all-cause mortality and serum intact parathyroid hormone (iPTH), calcium, and phosphate are fairly diverse in patients on maintenance hemodialysis according to prior studies. This study evaluated the association of chronic kidney disease-mineral and bone disorder (CKD-MBD) markers with all-cause mortality in prevalent hemodialysis patients from 2007 to 2012 in Beijing, China. A cohort, involving 8530 prevalent hemodialysis patients who had undergone a 6-70 months follow-up program (with median as 40 months) was formed. Related data was recorded from the database in 120 hemodialysis centers of Beijing Health Bureau (2007 to 2012). Information regarding baseline demographics, blood CKD-MBD markers and all-cause mortality was retrospectively reviewed. By using multivariate Cox regression model analysis, patients with a low iPTH level at baseline were found to have greater risk of mortality (<75pg/ml, HR = 1.36, 95% confidence interval (CI) 1.16-1.60) than those with a baseline iPTH level within 150-300 pg/ml. Similarly, death risk showed an increase when the baseline serum calcium presented a low level (<2.1mmol/L, HR = 1.54; 95% CI 1.37-1.74). Levels of baseline serum phosphorus were not associated with the risk of death. Similar results appeared through the baseline competing risks regression analysis. Patients with a lower level of serum iPTH or calcium are at a higher risk of all-cause mortality compared with those within the range recommended by Kidney Disease Outcome Quality Initiative (KDOQI) guidelines.

A systemic lupus erythematosus patient presenting as type B insulin resistance complicated with cryoglobulinemia

Systemic lupus erythematosus (SLE) patients may present with various symptoms and multisystem damage. We reported a 63-year-old male patient with SLE presenting as type B insulin resistance (TBIR) complicated with cryoglobulinemia. TBIR is an extremely rare disease, which is a manifestation of anti-insulin receptor antibodies (AIRA). Clinical feature is a sudden onset of hyperglycemia with major weight loss; however, the ensuing refractory hypoglycemia is more fatal. The average dosage of exogenous insulin is 5100 U/d. SLE patients with AIRA had poor prognosis, most of whom died of SLE activity. Cryoglobulins are immunoglobulins that reversibly precipitate in the cold, which will induce clinical symptoms. Non-infectious mixed cryoglobulinemia is frequently secondary to autoimmune diseases, such as SLE. Our patient was prescribed methylprednisolone (MP) and cyclophosphamide (CTX). Finally he had remission during the short-term follow-up. To our knowledge, this is the first case report of an SLE patient presenting as TBIR complicated with cryoglobulinemia.

Unfractionated Heparin Promotes Osteoclast Formation in Vitro by Inhibiting Osteoprotegerin Activity

Heparin has been proven to enhance bone resorption and induce bone loss. Since osteoclasts play a pivotal role in bone resorption, the effect of heparin on osteoclastogenesis needs to be clarified. Since osteocytes are the key modulator during osteoclastogenesis, we evaluated heparin’s effect on osteoclastogenesis in vitro by co-culturing an osteocyte cell line (MLO-Y4) and pre-osteoclasts (RAW264.7). In this co-culture system, heparin enhanced osteoclastogenesis and osteoclastic bone resorption while having no influence on the production of RANKL (receptor activator of NFκB ligand), M-CSF (macrophage colony-stimulating factor), and OPG (osteoprotegerin), which are three main regulatory factors derived from osteocytes. According to previous studies, heparin could bind specifically to OPG and inhibit its activity, so we hypothesized that this might be a possible mechanism of heparin activity. To test this hypothesis, osteoclastogenesis was induced using recombinant RANKL or MLO-Y4 supernatant. We found that heparin has no effect on RANKL-induced osteoclastogenesis (contains no OPG). However, after incubation with OPG, the capacity of MLO-Y4 supernatant for supporting osteoclast formation was increased. This effect disappeared after OPG was neutralized and reappeared after OPG was replenished. These results strongly suggest that heparin promotes osteocyte-modulated osteoclastogenesis in vitro, at least partially, through inhibiting OPG activity.

Efficacy and safety of Cinacalcet on secondary hyperparathyroidism in Chinese chronic kidney disease patients receiving hemodialysis

Introduction Secondary hyperparathyroidism (SHPT) develops in patients with chronic renal failure. Cinacalcet hydrochloride has been used successfully in U.S., Europe, and Japan in the treatment of SHPT, while maintaining serum levels of calcium and phosphorus. The efficacy and safety profile of Cinacalcet treatment vs. conventional treatments has been of great interest in clinical practice. In this recent phase III study conducted in China, efficacy and safety of a calcimimetic agent, Cinacalcet (Kyowa Hakko Kirin Co., Ltd.), were assessed for SHPT treatment in stable chronic renal disease patients on hemodialysis. Methods In this double-blind, multicenter, placebo-controlled, randomized phase III study, 238 subjects were enrolled in 12 centers and randomly divided into a Cinacalcet group and a placebo group. The percentage of patients achieving a serum parathyroid hormone (PTH) level ≤250 pg/mL was the primary efficacy end point. Serum calcium and phosphorus levels were measured. Adverse events and serious adverse events were recorded, and causal analysis performed. Findings In primary analysis, 25.4% of the Cinacalcet group and 3.5% of the placebo group achieved the primary end point (PTH ≤250 pg/mL). Calcium and phosphorus levels and calcium-phosphorus product were lower in the Cinacalcet group compared with the placebo group. Eleven serious adverse events were reported and considered to be not related to study drugs. Mild to moderate hypocalcemia and reduced calcium levels were reported and considered to be Cinacalcet related. Discussion This phase III study demonstrated that Cinacalcet is effective and well tolerated in treating SHPT in Chinese chronic kidney disease patients on hemodialysis, and in a patient population with much higher baseline PTH levels.

Anemia Management in the China Dialysis Outcomes and Practice Patterns Study

BACKGROUND

As the utilization of hemodialysis increases in China, it is critical to examine anemia management.

METHODS

Using data from the China Dialysis Outcomes and Practice Patterns Study (DOPPS), we describe hemoglobin (Hgb) distribution and anemia-related therapies.

RESULTS

Twenty one percent of China's DOPPS patients had Hgb <9 g/dl, compared with ≤10% in Japan and North America. A majority of medical directors targeted Hgb ≥11. Patients who were female, younger, or recently hospitalized had higher odds of Hgb <9; those with insurance coverage or on twice weekly dialysis had lower odds of Hgb <9. Iron use and erythropoietin-stimulating agents (ESAs) dose were modestly higher for patients with Hgb <9 compared with Hgb in the range 10-12.

CONCLUSION

A large proportion of hemodialysis patients in China's DOPPS do not meet the expressed Hgb targets. Less frequent hemodialysis, patient financial contribution, and lack of a substantial increase in ESA dose at lower Hgb concentrations may partially explain this gap. Video Journal Club 'Cappuccino with Claudio Ronco' at http://www.karger.com/?doi=442741.

Design and participant baseline characteristics of 'A Clinical Trial of IntensiVE Dialysis': the ACTIVE Dialysis Study

AIMS

Observational reports suggest extended dialysis hours are associated with improved outcomes. These findings are confounded by better prognostic characteristics among people practising extended hours. The aim of this article is to provide an overview of the methods and baseline characteristics for ACTIVE Dialysis Study participants.

METHODS

This multicentre, randomized, open-label, blinded endpoint-assessment trial randomized participants receiving maintenance haemodialysis therapy to either extended (≥24 h) or standard (12-18 h) weekly haemodialysis for 12 months. A web-based randomization system used minimization to ensure balanced allocation across regions, dialysis setting and dialysis vintage. The primary outcome is the change in quality of life over 12 months of study treatment assessed by EQ-5D. Secondary outcomes include change in left ventricular mass index assessed by magnetic resonance imaging and safety outcomes including dialysis access events.

RESULTS

A total of 200 participants were recruited between 2009 and 2013 from Australia (29.0%), China (62.0%), Canada (5.5%) and New Zealand (3.5%). Participants had a mean age of 52 (± 12) years and 11.5% were dialysing at home, with a mean duration of 13.9 h per week over a median of three sessions. At baseline, 32.5% had a history of cardiovascular disease and 36.5% had diabetes.

CONCLUSION

The ACTIVE Dialysis Study has met its planned recruitment target. The participant population are drawn from a range of health service settings in a global context. The study will contribute important evidence on the benefits and harms of extending weekly dialysis hours. The trial is registered at clinicaltrials.gov (NCT00649298).

Two-times weekly hemodialysis in China: frequency, associated patient and treatment characteristics and Quality of Life in the China Dialysis Outcomes and Practice Patterns study

BACKGROUND

Renal replacement therapy is rapidly expanding in China, and two-times weekly dialysis is common, but detailed data on practice patterns are currently limited. Using cross-sectional data from the China Dialysis Outcomes and Practice Patterns Study (DOPPS), we describe the hemodialysis practice in China compared with other DOPPS countries, examining demographic, social and clinical characteristics of patients on two-times weekly dialysis.

METHODS

The DOPPS protocol was implemented in 2011 among a cross-section of 1379 patients in 45 facilities in Beijing, Guangzhou and Shanghai. Data from China were compared with a cross section of 11 054 patients from the core DOPPS countries (collected 2009-11). Among China DOPPS patients, logistic and linear regression were used to describe the association of dialysis frequency with patient and treatment characteristics and quality of life.

RESULTS

A total of 26% of the patients in China were dialyzing two times weekly, compared with < 5% in other DOPPS regions. Standardized Kt/V was lowest in China (2.01) compared with other regions (2.12-2.27). Female sex, shorter dialysis vintage, lower socioeconomic status, less health insurance coverage, and lack of diabetes and hypertension were associated with dialyzing two times weekly (versus three times weekly). Patients dialyzing two times per week had longer treatment times and lower standardized Kt/V, but similar quality of life scores.

CONCLUSIONS

Two-times weekly dialysis is common in China, particularly among patients, who started dialysis more recently, have a lower comorbidity burden and have financial constraints. Quality of life scores do not differ between the two-times and three-times weekly groups. The effect on clinical outcomes merits further study.

Comparison of bioimpedance and clinical methods for dry weight prediction in maintenance hemodialysis patients

BACKGROUND

Bioelectrical impedance analysis (BIA) is a promising technique to evaluate dry weight. We compared the dry weight calculated by the three BIA equations Carlo Basile (CB) , Yanna Dou (YD) and the body composition spectroscopy (BCS) with clinical evaluation in maintenance hemodialysis (MHD) patients.

METHODS

The dry weight of enrolled MHD patients (DWClin) was evaluated under strict clinical surveillance. The whole-body resistances at 50 kHz, intra- and extracellular resistances were measured to calculate the dry weight (DWCB, DWYD and DWBCS) using each of the three equations.

RESULTS

Neither DWCB nor DWBCS were statistically different compared to DWClin (DWCB 63.2 ± 17.2 vs. 63.1 ± 16.1 kg; DWBCS 62.8 ± 16.8 vs. 63.1 ± 16.1 kg, p > 0.05). DWYD was significantly lower than DWClin (DWYD 62.0 ± 16.1 vs. 63.1 ± 16.1 kg, p < 0.05). The bias between DWCB and DWClin was the smallest among these three methods (ΔDWCB -0.1 ± 1.4 kg; ΔDWYD 1.1 ± 2.9 kg; ΔDWBCS 0.3 ± 1.8 kg).

CONCLUSION

The CB equations have better consistency with clinical dry weight in MHD patients.

Relative risks of chronic kidney disease for mortality and end-stage renal disease across races are similar

Some suggest race-specific cutpoints for kidney measures to define and stage chronic kidney disease (CKD), but evidence for race-specific clinical impact is limited. To address this issue, we compared hazard ratios of estimated glomerular filtration rates (eGFR) and albuminuria across races using meta-regression in 1.1 million adults (75% Asians, 21% whites, and 4% blacks) from 45 cohorts. Results came mainly from 25 general population cohorts comprising 0.9 million individuals. The associations of lower eGFR and higher albuminuria with mortality and end-stage renal disease (ESRD) were largely similar across races. For example, in Asians, whites, and blacks, the adjusted hazard ratios (95% confidence interval) for eGFR 45-59 vs. 90-104 ml/min/1.73m² were 1.3 (1.2-1.3), 1.1 (1.0-1.2) and 1.3 (1.1-1.7) for all-cause mortality, 1.6 (1.5-1.7), 1.4 (1.2-1.7), and 1.4 (0.7-2.9) for cardiovascular mortality, and 27.6 (11.1-68.7), 11.2 (6.0-20.9), and 4.1 (2.2-7.5) for ESRD, respectively. The corresponding HRs for ACR 30-299 mg/g or dipstick 1+ compared with ACR <10 or dipstick negative were 1.61 (1.41-1.84), 1.7 (1.5-1.9) and 1.8 (1.7-2.1) for all-cause mortality, 1.7 (1.4-2.0), 1.8 (1.5-2.1), and 2.8 (2.2-3.6) for cardiovascular mortality, and 7.4 (2.0-27.6), 4.0 (2.8-5.9), and 5.6 (3.4-9.2) for ESRD, respectively. Thus, the relative mortality or ESRD risks of lower eGFR and higher albuminuria were largely similar among three major races, supporting similar clinical approach to CKD definition and staging, across races.

Efficacy and initial dose determination of paricalcitol for treatment of secondary hyperparathyroidism in Chinese subjects

AIM

Prevalence of secondary hyperparathyroidism (SHPT), a renal disease complication, is increasing in China. Available therapies may not optimally control SHPT, particularly in patients with hypercalcemia, hyperphosphatemia, and parathyroid hyperplasia. This study examined efficacy and safety of two dosing regimens of selective vitamin D receptor activator paricalcitol.

MATERIALS AND METHODS

Subjects with SHPT (n = 216) undergoing hemodialysis were treated with paricalcitol i.v. for 12 weeks. One group was treated according to the EU paricalcitol package insert (PI) (initial μg dose based on iPTH/80), and the other was treated according to the US PI (initial dose of 0.04 μg/kg). Dose titration was based on iPTH and serum calcium (Ca) and phosphorus (P) levels.

RESULTS

The primary endpoint of two consecutive ≥ 30% iPTH decreases was achieved by 88.6% and 55.9% of subjects in the EU and US PI groups, respectively. Noninferiority of the EU PI group vs. the US PI group was demonstrated (lower bound of the 1-sided 97.5% CI = 21.3%). Superiority of the EU PI group was shown (lower limit > 0%) and confirmed by Fisher's exact test (p < 0.001); both groups showed similar achievement of recommended KDIGO iPTH levels. Ca and P levels were relatively constant.

CONCLUSION

Both EU and US PI paricalcitol dosing strategies effectively reduced iPTH levels in Chinese subjects with SHPT, with minimal impact on Ca and P levels.

Effects of unfractionated heparin on renal osteodystrophy and vascular calcification in chronic kidney disease rats

Unfractionated heparin (UFH) is the most widely used anticoagulant in hemodialysis for chronic kidney disease (CKD) patients. Many studies have verified that UFH can induce bone loss in subjects with normal bone, but few have focused on its effect on renal osteodystrophy. We therefore investigated this issue in adenine-induced CKD rats. As CKD also impairs mineral metabolism systemically, we also studied the impacts of UFH on serum markers of CKD-mineral and bone disorder (CKD-MBD) and vascular calcification. We administered low and high doses of UFH (1U/g and 2U/g body weight, respectively) to CKD rats and compared them with CKD controls. At sacrifice, the serum markers of CKD-MBD did not significantly differ among the two UFH CKD groups and the CKD control group. The mean bone mineral densities (BMDs) of the total femur and a region of interest (ROI) constituted of trabecular and cortical bone were lower in the high-dose UFH (H-UFH) CKD group than in the CKD control group (P<0.05 and P<0.01, respectively). The BMD of the femoral ROI constituted of cortical bone did not differ between the H-UFH CKD group and the CKD control group. Histomorphometrical changes in the CKD rats indicated secondary hyperparathyroidism, and the femoral trabecular bone volume, but not cortical bone volume, significantly decreased with increasing UFH dose. The same decreasing trend was found in osteoblast parameters, and an increasing trend was found in osteoclast parameters; however, most differences were not significant. Moreover, no distinct statistical differences were found in the comparison of vascular calcium or phosphorus content among the CKD control group and the two UFH CKD groups. Therefore, we concluded that UFH could induce bone loss in CKD rats with secondary hyperparathyroidism, mainly by reducing the trabecular volume and had little effect on cortical bone volume. The underlying mechanism might involve inhibition of osteoblast activity and promotion of osteoclast activity by UFH. We did not find any effect of UFH on vascular calcification in CKD rats with secondary hyperparathyroidism.

Cross-over study of influence of oral vitamin C supplementation on inflammatory status in maintenance hemodialysis patients

BACKGROUND

Both vitamin C deficiency and inflammation are prevalent in maintenance hemodialysis (MHD) patients. In this study, we aimed to elucidate the effect of oral vitamin C supplementation on inflammatory status in MHD patients with low vitamin C level and high hypersensitive C-reactive protein (hs-CRP) level.

METHODS

A total of 128 patients were recruited in our present study. Patients were divided into two groups. In group 1 (n = 67), patients were orally administered with 200 mg/day vitamin C in the first 3 months, and then the vitamin C supplementation was withdrawn in the next 3 months. In group 2 (n = 61), patients were not given vitamin C in the first 3 months, and then they were orally administered with 200 mg/day in the next 3 months. Levels of hs-CRP, prealbumin, albumin and hemoglobin as well as the EPO resistance index (ERI) were determined at the baseline and every 3 months throughout the study. Plasma vitamin C level was determined by high-performance liquid chromatography with UV detection.

RESULTS

Among the 128 patients, 28 of them dropped out of the study before completion. Consequently, a total of 100 patients (group 1: n = 48; group 2: n = 52) were included in the final analysis. At the baseline, the plasma vitamin C level of all patients was less than 4 μg/mL. However, this proportion was decreased to 20% after the vitamin C supplementation for 3 months. Compared with patients without the vitamin C supplementation, a decreased level of hs-CRP and an increased level of prealbumin were induced by the vitamin C supplementation for 3 months in both groups. However, levels of these biomarkers returned to their original state after the supplementation was withdrawn. Same beneficial effects on plasma albumin, hemoglobin and ERI response to vitamin C supplementation were observed in the two groups without statistical significance.

CONCLUSIONS

The inflammatory status in MHD patients with plasma vitamin C deficiency and high levels of inflammatory markers could be partially improved by long-term oral administration of small doses of vitamin C.

TRIAL REGISTRATION

The clinical trial number: NCT01356433.

Sevelamer carbonate lowers serum phosphorus effectively in haemodialysis patients: a randomized, double-blind, placebo-controlled, dose-titration study

BACKGROUND

Hyperphosphataemia in patients with advanced chronic kidney disease (CKD) is associated with adverse outcomes, including vascular calcification and higher mortality rates. While phosphate lowering is an integral aspect of CKD management, the efficacy and safety of phosphate binders in a contemporary cohort of Chinese haemodialysis patients (who have different genetics and dietary patterns than other populations) has not been previously described. Moreover, sparse data are available on strategies for optimal dose titration when transitioning from a calcium-based to a polymer-based phosphate binder.

METHODS

This randomized, double-blind, dose-titration study compared sevelamer carbonate (starting dose 800 mg three times daily) with placebo over 8 weeks' duration in Chinese CKD patients on haemodialysis. Patients were required to be using calcium-based binders prior to study start.

RESULTS

In all, 205 patients were randomized (sevelamer, n = 135; placebo, n = 70); mean age was 48.6 years, 61% were male and the mean time on dialysis was 4.4 years. The mean serum phosphorus decreased significantly in patients treated with sevelamer carbonate [change -0.69 ± 0.64 mmol/L (-2.14 ± 1.98 mg/dL)] but remained persistently elevated with placebo [change -0.06 ± 0.57 mmol/L (-0.19 ± 1.76 mg/dL)] (P < 0.0001). When compared with placebo, sevelamer carbonate treatment resulted in statistically significant greater mean reductions from baseline in serum total (-17.1 versus -3.3%) and low-density lipoprotein cholesterol (-33.5 versus-7.6%) (P < 0.0001 for both). Sevelamer carbonate was well tolerated with 96% adherence compared with 97% adherence in the placebo arm. Overall, adverse events experienced by patients in the sevelamer carbonate and placebo treatment groups were similar and consistent with their underlying renal disease.

CONCLUSIONS

This study demonstrated that hyperphosphataemia developed quickly following the cessation of phosphate binders and remained persistently elevated in end-stage CKD in the placebo-treated group. Gradually titrating up sevelamer carbonate from an initial dose of 2.4 g/day to an average daily dose of 7.1 ± 2.5 g/day was well tolerated, safe and efficacious in contemporary Chinese haemodialysis patients.

Dialysis initiation: what's the rush?

The recent trend to early initiation of dialysis (at eGFR >10 ml/min/1.73 m(2) ) appears to have been based on conventional wisdoms that are not supported by evidence. Observational studies using administrative databases report worse comorbidity-adjusted dialysis survival with early dialysis initiation. Although some have concluded that the IDEAL randomized controlled trial of dialysis start provided evidence that patients become symptomatic with late dialysis start, there is no definitive support for this view. The potential harms of early start of dialysis, including the loss of residual renal function (RRF), have been well documented. The rate of RRF loss (renal function trajectory) is an important consideration for the timing of the dialysis initiation decision. Patients with low glomerular filtration rate (GFR) may have sufficient RRF to be maintained off dialysis for years. Delay of dialysis start until a working arterio-venous access is in place seems prudent in light of the lack of harm and possible benefit of late dialysis initiation. Prescribing frequent hemodialysis is not recommended when dialysis is initiated early. The benefits of early initiation of chronic dialysis after episodes of congestive heart failure or acute kidney injury require further study. There are no data to show that early start benefits diabetics or other patient groups. Preemptive start of dialysis in noncompliant patients may be necessary to avoid complications. The decision to initiate dialysis requires informed patient consent and a joint decision by the patient and dialysis provider. Possible talking points for obtaining informed consent are provided.

Chronic kidney disease: global dimension and perspectives

Chronic kidney disease is defined as a reduced glomerular filtration rate, increased urinary albumin excretion, or both, and is an increasing public health issue. Prevalence is estimated to be 8-16% worldwide. Complications include increased all-cause and cardiovascular mortality, kidney-disease progression, acute kidney injury, cognitive decline, anaemia, mineral and bone disorders, and fractures. Worldwide, diabetes mellitus is the most common cause of chronic kidney disease, but in some regions other causes, such as herbal and environmental toxins, are more common. The poorest populations are at the highest risk. Screening and intervention can prevent chronic kidney disease, and where management strategies have been implemented the incidence of end-stage kidney disease has been reduced. Awareness of the disorder, however, remains low in many communities and among many physicians. Strategies to reduce burden and costs related to chronic kidney disease need to be included in national programmes for non-communicable diseases.