A Polynesian-specific copy number variant encompassing the MICA gene associates with gout.

Gout is of particularly high prevalence in the Maori and Pacific (Polynesian) populations of Aotearoa New Zealand (NZ). Here, we investigated the contribution of common population-specific copy number variation (CNV) to gout in the Aotearoa NZ Polynesian population. Microarray-generated genome-wide genotype data from Aotearoa NZ Polynesian individuals with (n = 1196) and without (n = 1249) gout were analyzed. Comparator population groups were 552 individuals of European ancestry and 1962 of Han Chinese ancestry. Levels of circulating major histocompatibility complex (MHC) class I polypeptide-related sequence A (MICA) were measured by enzyme-linked immunosorbent assay. Fifty-four CNV regions (CNVRs) appearing in at least 10 individuals were detected, of which seven common (>2%) CNVRs were specific to or amplified in Polynesian people. A burden test of these seven revealed associations of insertion/deletion with gout (odds ratio (OR) 95% confidence interval [CI] = 1.80 [1.01; 3.22], P = 0.046). Individually testing of the seven CNVRs for association with gout revealed nominal association of CNVR1 with gout in Western Polynesian (Chr6: 31.36-31.45 Mb, OR = 1.72 [1.03; 2.92], P = 0.04), CNVR6 in the meta-analyzed Polynesian sample sets (Chr1: 196.75-196.92 Mb, OR = 1.86 [1.16; 3.00], P = 0.01) and CNVR9 in Western Polynesian (Chr1: 189.35-189.54 Mb, OR = 2.75 [1.15; 7.13], P = 0.03). Analysis of European gout genetic association data demonstrated a signal of association at the CNVR1 locus that was an expression quantitative trait locus for MICA. The most common CNVR (CNVR1) includes deletion of the MICA gene, encoding an immunomodulatory protein. Expression of MICA was reduced in the serum of individuals with the deletion. In summary, we provide evidence for the association of CNVR1 containing MICA with gout in Polynesian people, implicating class I MHC-mediated antigen presentation in gout.

Effects of Allopurinol on the Progression of Chronic Kidney Disease.

BACKGROUND: Elevated serum urate levels are associated with progression of chronic kidney disease. Whether urate-lowering treatment with allopurinol can attenuate the decline of the estimated glomerular filtration rate (eGFR) in patients with chronic kidney disease who are at risk for progression is not known. METHODS: In this randomized, controlled trial, we randomly assigned adults with stage 3 or 4 chronic kidney disease and no history of gout who had a urinary albumin:creatinine ratio of 265 or higher (with albumin measured in milligrams and creatinine in grams) or an eGFR decrease of at least 3.0 ml per minute per 1.73 m2 of body-surface area in the preceding year to receive allopurinol (100 to 300 mg daily) or placebo. The primary outcome was the change in eGFR from randomization to week 104, calculated with the Chronic Kidney Disease Epidemiology Collaboration creatinine equation. RESULTS: Enrollment was stopped because of slow recruitment after 369 of 620 intended patients were randomly assigned to receive allopurinol (185 patients) or placebo (184 patients). Three patients per group withdrew immediately after randomization. The remaining 363 patients (mean eGFR, 31.7 ml per minute per 1.73 m2; median urine albumin:creatinine ratio, 716.9; mean serum urate level, 8.2 mg per deciliter) were included in the assessment of the primary outcome. The change in eGFR did not differ significantly between the allopurinol group and the placebo group (-3.33 ml per minute per 1.73 m2 per year [95% confidence interval {CI}, -4.11 to -2.55] and -3.23 ml per minute per 1.73 m2 per year [95% CI, -3.98 to -2.47], respectively; mean difference, -0.10 ml per minute per 1.73 m2 per year [95% CI, -1.18 to 0.97]; P = 0.85). Serious adverse events were reported in 84 of 182 patients (46%) in the allopurinol group and in 79 of 181 patients (44%) in the placebo group. CONCLUSIONS: In patients with chronic kidney disease and a high risk of progression, urate-lowering treatment with allopurinol did not slow the decline in eGFR as compared with placebo. (Funded by the National Health and Medical Research Council of Australia and the Health Research Council of New Zealand; CKD-FIX Australian New Zealand Clinical Trials Registry number, ACTRN12611000791932.).

Plasma Exchange and Glucocorticoids in Severe ANCA-Associated Vasculitis.

BACKGROUND: More effective and safer treatments are needed for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. METHODS: We conducted a randomized trial with a 2-by-2 factorial design to evaluate the use of plasma exchange and two regimens of oral glucocorticoids in patients with severe ANCA-associated vasculitis (defined by an estimated glomerular filtration rate of <50 ml per minute per 1.73 m2 of body-surface area or diffuse pulmonary hemorrhage). Patients were randomly assigned to undergo plasma exchange (seven plasma exchanges within 14 days after randomization) or no plasma exchange (control group). Patients were also randomly assigned to follow either a standard-dose regimen or a reduced-dose regimen of oral glucocorticoids. Patients were followed for up to 7 years for the primary composite outcome of death from any cause or end-stage kidney disease (ESKD). RESULTS: Death from any cause or ESKD occurred in 100 of 352 patients (28.4%) in the plasma-exchange group and in 109 of 352 patients (31.0%) in the control group (hazard ratio, 0.86; 95% confidence interval [CI], 0.65 to 1.13; P = 0.27). The results were similar in subgroup analyses and in analyses of secondary outcomes. We also assessed the noninferiority of a reduced-dose regimen of glucocorticoids to a standard-dose regimen, using a noninferiority margin of 11 percentage points. Death from any cause or ESKD occurred in 92 of 330 patients (27.9%) in the reduced-dose group and in 83 of 325 patients (25.5%) in the standard-dose group (absolute risk difference, 2.3 percentage points; 90% CI, -3.4 to 8.0), which met the criterion for noninferiority. Serious infections at 1 year were less common in the reduced-dose group than in the standard-dose group (incidence rate ratio, 0.69; 95% CI, 0.52 to 0.93), but other secondary outcomes were similar in the two groups. CONCLUSIONS: Among patients with severe ANCA-associated vasculitis, the use of plasma exchange did not reduce the incidence of death or ESKD. A reduced-dose regimen of glucocorticoids was noninferior to a standard-dose regimen with respect to death or ESKD. (Funded by the U.K. National Institute for Health Research and others; PEXIVAS Current Controlled Trials number, ISRCTN07757494; ClinicalTrials.gov number, NCT00987389.).

Mid-pass whole genome sequencing enables biomedical genetic studies of diverse populations.

BACKGROUND: Historically, geneticists have relied on genotyping arrays and imputation to study human genetic variation. However, an underrepresentation of diverse populations has resulted in arrays that poorly capture global genetic variation, and a lack of reference panels. This has contributed to deepening global health disparities. Whole genome sequencing (WGS) better captures genetic variation but remains prohibitively expensive. Thus, we explored WGS at "mid-pass" 1-7x coverage. RESULTS: Here, we developed and benchmarked methods for mid-pass sequencing. When applied to a population without an existing genomic reference panel, 4x mid-pass performed consistently well across ethnicities, with high recall (98%) and precision (97.5%). CONCLUSION: Compared to array data imputed into 1000 Genomes, mid-pass performed better across all metrics and identified novel population-specific variants with potential disease relevance. We hope our work will reduce financial barriers for geneticists from underrepresented populations to characterize their genomes prior to biomedical genetic applications.

Intracellular activation of 4-hydroxycyclophosphamide into a DNA-alkylating agent in human leucocytes.

1.The conversion of the cyclophosphamide intermediate metabolite 4-hydroxycyclophosphamide (4-OHCP) to the final cytotoxic metabolite phosphoramide mustard (PAM) is classically assumed to occur via chemical hydrolysis of the phospho-ester bond. Whilst it has been suggested previously that this reaction could be enzyme-catalysed, there was only indirect evidence for this (i.e. formation of the by-product acrolein).2. Using an assay to detect formation of DNA-alkylating adducts which block PCR amplification (QPCR-block assay), we have demonstrated that 4-OHCP can be activated by peripheral blood mononuclear cells (PBMC). The DNA-alkylating potency of 4-OHCP in PBMC increased >18-fold compared to the intrinsic reactivity of 4-OHCP for purified gDNA.3. We also found that immortalised T-cells (Jurkat) had a similar ability to activate 4-OHCP into a DNA alkylating agent, whereas there was no appreciable activation in epithelial derived (Caco-2) cells. This suggests the possibility of tissue-specific enzyme expression.4. Of the candidate enzymes tested only recombinant human cAMP-phosphodiesterase-PDE4B and snake-venom phosphodiesterase (PDE-I) could catalyse this activation into a DNA-alkylating agent.5. This enzymatic catalysis of the phospho-ester bond (P-O-C) is a hitherto unrecognised feature of this important immunomodulatory drug and should be investigated further.

Effect of Low-Sodium versus Conventional Sodium Dialysate on Left Ventricular Mass in Home and Self-Care Satellite Facility Hemodialysis Patients: A Randomized Clinical Trial.

BACKGROUND: Fluid overload in patients undergoing hemodialysis contributes to cardiovascular morbidity and mortality. There is a global trend to lower dialysate sodium with the goal of reducing fluid overload. METHODS: To investigate whether lower dialysate sodium during hemodialysis reduces left ventricular mass, we conducted a randomized trial in which patients received either low-sodium dialysate (135 mM) or conventional dialysate (140 mM) for 12 months. We included participants who were aged >18 years old, had a predialysis serum sodium ≥135 mM, and were receiving hemodialysis at home or a self-care satellite facility. Exclusion criteria included hemodialysis frequency >3.5 times per week and use of sodium profiling or hemodiafiltration. The main outcome was left ventricular mass index by cardiac magnetic resonance imaging. RESULTS: The 99 participants had a median age of 51 years old; 67 were men, 31 had diabetes mellitus, and 59 had left ventricular hypertrophy. Over 12 months of follow-up, relative to control, a dialysate sodium concentration of 135 mmol/L did not change the left ventricular mass index, despite significant reductions at 6 and 12 months in interdialytic weight gain, in extracellular fluid volume, and in plasma B-type natriuretic peptide concentration (ratio of intervention to control). The intervention increased intradialytic hypotension (odds ratio [OR], 7.5; 95% confidence interval [95% CI], 1.1 to 49.8 at 6 months and OR, 3.6; 95% CI, 0.5 to 28.8 at 12 months). Five participants in the intervention arm could not complete the trial because of hypotension. We found no effect on health-related quality of life measures, perceived thirst or xerostomia, or dietary sodium intake. CONCLUSIONS: Dialysate sodium of 135 mmol/L did not reduce left ventricular mass relative to control, despite improving fluid status. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: The Australian New Zealand Clinical Trials Registry, ACTRN12611000975998.

The Maori and Pacific specific CREBRF variant and adult height.

BACKGROUND: The CREBRF missense variant (p.Arg457Gln) is paradoxically associated with lower risk of type 2 diabetes, yet higher body mass index (BMI). Here we sought to determine whether this CREBRF variant might be associated with adult height. METHODS: Linear regression was used to analyse the association of the CREBRF minor (A) allele with height in 2286 Maori and Pacific adults living in Aotearoa/New Zealand. A potential type 2 diabetes index event was corrected to account for a bias that may be the cause of paradoxical association between the CREBRF diabetes-protective allele and higher BMI and height. RESULTS: The CREBRF protective allele was associated with increased adult height (ß = 1.25 cm, P = 3.9 × 10-6), with the effect being more pronounced in males. The lower odds of diabetes remained similar when analyses were adjusted for height (OR = 0.67-0.65). We found no evidence of a diabetes index event bias to explain the paradoxical effect of CREBRF with either BMI or height and diabetes. The orthologous CREBRF p.Arg457Gln variant was created in knock-in mice to independently assess the effect of the variant, and length was found to be greater in male mice at 8 weeks of age. CONCLUSION: These data taken together indicate that CREBRF p.Arg457Gln is associated with taller stature in Maori and Pacific adults.

Predictors of Change in Left-Ventricular Structure and Function in a Trial of Extended Hours Hemodialysis.

BACKGROUND: Myocardial pathology is common in patients undergoing hemodialysis. To explore the effects of differing aspects of dialysis treatment on its evolution, we examined the impact of change in markers of volume status, hemodynamics and solute clearance on left ventricular (LV) parameters in a randomized trial of extended hours dialysis. METHODS AND RESULTS: A Clinical Trial of IntensiVE (ACTIVE) Dialysis randomized 200 patients undergoing hemodialysis to extended dialysis hours (≥ 24 hours/week) or standard hours (12-18 hours/week) for 12 months. In a prespecified substudy, 95 participants underwent cardiac magnetic resonance imaging (CMR) at baseline and at the study's end. Generalized linear regression was used to model the relationship between changes in LV parameters and markers of volume status (normalized ultrafiltration rate and total weekly interdialytic weight gain), hemodynamic changes (systolic and diastolic blood pressure) and solute control (urea clearance, dialysis hours and phosphate). Randomization to extended hours dialysis was not associated with change in any CMR parameter. Reduction in ultrafiltration rate was associated with reduction in LV mass index (P = 0.049) and improved ejection fraction (P = 0.024); reduction in systolic blood pressure was also associated with improvement in ejection fraction (P = 0.045); reduction in interdialytic weight gain was associated with reduced stroke volume (P = 0.038). There were no associations between change in urea clearance, phosphate or total hours per week and CMR parameters. CONCLUSIONS: Reduction in ultrafiltration rate and blood pressure are associated with improved myocardial parameters in hemodialysis recipients independently of solute clearance or dialysis time. These findings underscore the importance of fluid status and related parameters as potential treatment targets in this population.

No evidence of a legacy effect on survival following randomization to extended hours dialysis in the ACTIVE Dialysis trial.

AIM: Extended hours haemodialysis is associated with superior survival to standard hours. However, residual confounding limits the interpretation of this observation. We aimed to determine the effect of a period of extended hours dialysis on long-term survival among participants in the ACTIVE Dialysis trial. METHODS: Two-hundred maintenance haemodialysis recipients were randomized to extended hours dialysis (median 24 h/wk) or standard hours dialysis (median 12 h/wk) for 12 months. Further pre-specified observational follow up occurred at 24, 36 and 60 months. Vital status and modality of renal replacement therapy were ascertained. RESULTS: Over the 5 years, 38 participants died, 30 received a renal transplant, and 6 were lost to follow up. Total weekly dialysis hours did not differ between standard and extended groups during the follow-up period (14.1 hours [95%CI 13.4-14.8] vs 14.8 hours [95%CI 14.1-15.6]; P = .16). There was no difference in all-cause mortality (hazard ratio for extended hours 0.91 [95%CI 0.48-1.72]; P = .77). Similar results were obtained after censoring participants at transplantation, and after adjusting for potential confounding variables. Subgroup analysis did not reveal differences in treatment effect by region, dialysis setting or vintage (P-interaction .51, .54, .12, respectively). CONCLUSION: Twelve months of extended hours dialysis did not improve long-term survival nor affect dialysis hours after the intervention period. An urgent need remains to further define the optimal dialysis intensity across the broad range of dialysis recipients.

Mycophenolate mofetil versus cyclophosphamide for remission induction in ANCA-associated vasculitis: a randomised, non-inferiority trial.

OBJECTIVES: Cyclophosphamide induction regimens are effective for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), but are associated with infections, malignancies and infertility. Mycophenolate mofetil (MMF) has shown high remission rates in small studies of AAV. METHODS: We conducted a randomised controlled trial to investigate whether MMF was non-inferior to cyclophosphamide for remission induction in AAV. 140 newly diagnosed patients were randomly assigned to MMF or pulsed cyclophosphamide. All patients received the same oral glucocorticoid regimen and were switched to azathioprine following remission. The primary endpoint was remission by 6 months requiring compliance with the tapering glucocorticoid regimen. Patients with an eGFR <15 mL/min were excluded from the study. RESULTS: At baseline, ANCA subtype, disease activity and organ involvement were similar between groups. Non-inferiority was demonstrated for the primary remission endpoint, which occurred in 47 patients (67%) in the MMF group and 43 patients (61%) in the cyclophosphamide group (risk difference 5.7%, 90% CI -7.5% to 19%). Following remission, more relapses occurred in the MMF group (23 patients, 33%) compared with the cyclophosphamide group (13 patients, 19%) (incidence rate ratio 1.97, 95% CI 0.96 to 4.23, p=0.049). In MPO-ANCA patients, relapses occurred in 12% of the cyclophosphamide group and 15% of the MMF group. In PR3-ANCA patients, relapses occurred in 24% of the cyclophosphamide group and 48% of the MMF group. Serious infections were similar between groups (26% MMF group, 17% cyclophosphamide group) (OR 1.67, 95% CI 0.68 to 4.19, p=0.3). CONCLUSION: MMF was non-inferior to cyclophosphamide for remission induction in AAV, but resulted in higher relapse rate. TRIAL REGISTRATION NUMBER: NCT00414128.

Kidney Health Australia - Caring for Australasians with Renal Impairment guideline recommendations for infection control for haemodialysis units.

AIM: There is no national consensus on infection control in haemodialysis units in Australia and New Zealand. The primary aim of this guideline was to provide recommendations on screening for blood-borne viruses and multi-resistant organisms for dialysis units based on the available evidence. METHODS: The Kidney Health Australia Caring for Australasians with Renal Impairment guidelines, overall approach to guideline development follows the GRADE framework. A facilitated workshop was conducted to ensure that patient and caregiver concerns were considered. The evidence from relevant medical databases on the impact of screening on detection and transmission rates, hospitalization, mortality and psychosocial care, was reviewed and critically appraised. The guideline group made recommendations from the evidence available. RESULTS: The main guideline recommendations are: Dialysis units adopt a comprehensive approach that encompasses standard infection control precautions. Conduct routine surveillance for key blood-borne viruses and methicillin-resistant Staphylococcus aureus. Conduct routine surveillance of individual levels of protection against hepatitis B for patients on haemodialysis. Use dedicated dialysis machines for HBV-infected patients. The evidence in totality was not found to support routine surveillance of vancomycin-resistant Enterococci . Enhanced surveillance in light of the local risk of transmittable infectious agents should be considered by dialysis units. Very few studies have reported on the potential adverse effects of screening and associated practices. CONCLUSIONS: Future research should focus on the potential benefits and adverse effects of screening and associated practices on clinical outcomes including infections prevented and health service delivery, and psychosocial domains for patients. Given the results of trials in the critical setting, the effectiveness of methicillin-resistant Staphylococcus aureus decolonization in people receiving dialysis therapy warrants further research.

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).

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.

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.

Discordant association of the CREBRF rs373863828 A allele with increased BMI and protection from type 2 diabetes in Maori and Pacific (Polynesian) people living in Aotearoa/New Zealand.

AIMS/HYPOTHESIS: The A (minor) allele of CREBRF rs373863828 has been associated with increased BMI and reduced risk of type 2 diabetes in the Samoan populations of Samoa and American Samoa. Our aim was to test rs373863828 for associations with BMI and the odds of type 2 diabetes, gout and chronic kidney disease (CKD) in Maori and Pacific (Polynesian) people living in Aotearoa/New Zealand. METHODS: Linear and logistic regression models were used to analyse the association of the A allele of CREBRF rs373863828 with BMI, log-transformed BMI, waist circumference, type 2 diabetes, gout and CKD in 2286 adults. The primary analyses were adjusted for age, sex, the first four genome-wide principal components and (where appropriate) BMI, waist circumference and type 2 diabetes. The primary analysis was conducted in ancestrally defined groups and association effects were combined using meta-analysis. RESULTS: For the A allele of rs373863828, the effect size was 0.038 (95% CI 0.022, 0.055, p = 4.8 × 10-6) for log-transformed BMI, with OR 0.59 (95% CI 0.47, 0.73, p = 1.9 × 10-6) for type 2 diabetes. There was no evidence for an association of genotype with variance in BMI (p = 0.13), and nor was there evidence for associations with serum urate (ß = 0.012 mmol/l, pcorrected = 0.10), gout (OR 1.00, p = 0.98) or CKD (OR 0.91, p = 0.59). CONCLUSIONS/INTERPRETATION: Our results in New Zealand Polynesian adults replicate, with very similar effect sizes, the association of the A allele of rs373863828 with higher BMI but lower odds of type 2 diabetes among Samoan adults living in Samoa and American Samoa.

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).

Low Versus Standard Urine Output Targets in Patients Undergoing Major Abdominal Surgery: A Randomized Noninferiority Trial.

OBJECTIVE: To determine whether a low perioperative minimum urine output target is safe and fluid sparing when compared with the standard target. BACKGROUND: A minimum hourly urine output of 0.5 mL/kg is a key target guiding perioperative fluid therapy. Few data support this standard practice, which may contribute to perioperative fluid overloading. METHODS: We randomized patients without significant risk factors for acute kidney injury undergoing elective colectomy to a minimum urine output target of 0.2 mL/kg/h (low group) or 0.5 mL/kg/h (standard group) from induction of anesthesia until 8 AM 2 days after surgery. Maintenance fluids were standardized and additional fluids administered to achieve the targets. Primary outcome was noninferiority for urine neutrophil gelatinase-associated lipocalin on the day after surgery. RESULTS: Between November 21, 2011 and July 11, 2013, 40 participants completed the study. The low group received 3170 mL (95% confidence interval 2380-3960) intravenous fluids versus 5490 mL (95% confidence interval 4570-6410) in the standard group (P = 0.0004), and was noninferior for neutrophil gelatinase-associated lipocalin [14.7 µg/L (interquartile range 7.60-28.9) vs 18.4 µg/L (interquartile range 8.30-21.2); Pnoninferiority = 0.0011], serum cystatin C (Pnoninferiority < 0.0001), serum creatinine (Pnoninferiority = 0.0004), and measured glomerular filtration (Pnoninferiority = 0.0003). Effective renal plasma flow increased in both groups after surgery, and more in the standard group (Pnoninferiority = 0.125). CONCLUSIONS: A perioperative urine output target of 0.2 mL/kg/h is noninferior to the standard target of 0.5 mL/kg/h and results in a large intravenous fluid sparing. This target should be adopted in surgical patients without significant kidney injury risk factors.

A Novel Hypoxia-Inducible Factor-Prolyl Hydroxylase Inhibitor (GSK1278863) for Anemia in CKD: A 28-Day, Phase 2A Randomized Trial.

BACKGROUND: Anemia associated with chronic kidney disease (CKD) often requires treatment with recombinant human erythropoietin (EPO). Hypoxia-inducible factor-prolyl hydroxylase inhibitors (PHIs) stimulate endogenous EPO synthesis and induce effective erythropoiesis by non-EPO effects. GSK1278863 is an orally administered small-molecule PHI. STUDY DESIGN: Multicenter, single-blind, randomized, placebo-controlled, parallel-group study. SETTING & PARTICIPANTS: Anemic non-dialysis-dependent patients with CKD stages 3-5 (CKD-3/4/5 group; n=70) and anemic hemodialysis patients with CKD stage 5D (CKD-5D group; n=37). INTERVENTIONS: Patients with CKD-3/4/5 received placebo or GSK1278863 (10, 25, 50, or 100mg), and patients with CKD-5D received placebo or GSK1278863 (10 or 25mg) once daily for 28 days. OUTCOMES & MEASUREMENTS: Primary pharmacokinetic and pharmacodynamic (increase and response rates in achieving the target hemoglobin [Hb] concentration, plasma EPO concentrations, reticulocyte count, and others]) and safety and tolerability end points were obtained. RESULTS: Both CKD-3/4/5 and CKD-5D populations showed a dose-dependent increase in EPO concentrations and consequent increases in reticulocytes and Hb levels. Percentages of GSK1278863 participants with an Hb level increase > 1.0g/dL (CKD-3/4/5) and >0.5g/dL (CKD-5D) were 63% to 91% and 71% to 89%, respectively. Per-protocol-defined criteria, high rate of increase in Hb level, or high absolute Hb value was the main cause for withdrawal (CKD-3/4/5, 30%; CKD-5D, 22%). A dose-dependent decrease in hepcidin levels and increase in total and unsaturated iron binding were observed in all GSK1278863-treated patients. LIMITATIONS: Sparse pharmacokinetic sampling may have limited covariate characterization. EPO concentrations at the last pharmacodynamic sample (5-6 hours) postdose may not represent peak concentrations, which occurred 8 to 10 hours postdose in previous studies. Patients were not stratified by diabetes status, potentially confounding vascular endothelial growth factor and glucose analyses. CONCLUSIONS: GSK1278863 induced an effective EPO response and stimulated non-EPO mechanisms for erythropoiesis in anemic non-dialysis-dependent and dialysis-dependent patients with CKD.

Long-term outcomes of end-stage kidney disease for patients with IgA nephropathy: A multi-centre registry study.

BACKGROUND: Clinical outcomes of patients with end-stage kidney disease (ESKD) receiving renal replacement therapy (RRT) secondary to IgA nephropathy (IgAN) have not been well described. AIM: To investigate the characteristics, treatments and outcomes of ESKD because of kidney-limited IgAN and Henoch-Schönlein purpura nephritis (HSPN) in the Australian and New Zealand RRT populations. METHODS: All ESKD patients who commenced RRT in Australia and New Zealand between 1971 and 2012 were included. Dialysis and transplant outcomes were evaluated in both a contemporary cohort (1998-2012) and the entire cohort (1971-2012). RESULTS: Of 63 297 ESKD patients, 3721 had kidney-limited IgAN, and 131 had HSPN. For the contemporary cohort of IgAN patients on dialysis (n = 2194), 10-year patient survival was 65%. Of 1368 contemporary IgAN patients who received their first renal allograft, 10-year patient, overall renal allograft and death-censored renal allograft survival were 93%, 82% and 88%, respectively. Using multivariable Cox regression analysis, patients with IgAN had favourable dialysis patient survival (adjusted hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.57-0.69), overall renal allograft survival (HR 0.67, 95% CI 0.57-0.79) and renal transplant patient survival (HR 0.58, 95% CI 0.45-0.74) compared with ESKD controls. Similar results were found in the entire cohort and when using competing-risks models. Compared with kidney-limited IgAN patients, those with HSPN had worse dialysis patient survival (HR 1.94, 95% CI 1.02-3.69), overall renal allograft survival (HR 3.40, 95% CI 1.00-11.55) and renal transplant patient survival (HR 3.50, 95% CI 1.03-11.92). CONCLUSION: IgAN ESKD was associated with better dialysis and renal transplant outcomes compared with other forms of ESKD. The survival outcomes of ESKD patients with HSPN were worse than kidney-limited IgAN.