Effect of low-volume combined aerobic and resistance high-intensity interval training on vascular health in people with type 2 diabetes: a randomised controlled trial.

PURPOSE: We compared the effects of low-volume combined aerobic and resistance high-intensity interval training (C-HIIT), combined moderate-intensity continuous training (C-MICT) and waitlist control (CON) on vascular health after 8-weeks of supervised training, and an additional 10-months of self-directed training, in adults with type 2 diabetes (T2D). METHODS: Sixty-nine low active adults with T2D were randomised to 8-weeks of supervised C-HIIT (3 times/week, 78-min/week), C-MICT (current exercise guidelines, 4 times/week, 210-min/week) or CON. CON underwent usual care for 8-weeks before being re-randomised to C-HIIT or C-MICT. This was followed by 10-months of self-directed training for participants in C-HIIT and C-MICT. Vascular outcomes were evaluated at baseline, 8-weeks, and 12-months. RESULTS: After 8-weeks, supervised C-HIIT significantly improved relative flow-mediated dilation (FMD) compared with CON (mean difference [MD] 0.8% [0.1, 1.4], p = 0.025). Although not significantly different from CON, the magnitude of change in relative FMD following 8-weeks of supervised C-MICT was similar (MD 0.8% [-0.1, 1.7], p = 0.080). There were no differences in haemodynamic indices, carotid-femoral pulse wave velocity (cfPWV), or aortic reservoir pressure between groups at 8-weeks. After 12-months, there was a significant reduction in haemodynamic indices (time effect, p < 0.05) for both C-HIIT and C-MICT, with no between-group difference. The reduction in cfPWV over 12-months was significantly greater in C-MICT than C-HIIT (group × time effect, p = 0.018). There was no difference in FMD over time or between groups at 12-months. CONCLUSIONS: Short-term supervised C-HIIT and C-MICT both increased brachial artery FMD compared with CON. Long-term C-HIIT and C-MICT were beneficial for improving haemodynamic indices, but not brachial artery FMD. C-MICT was superior to C-HIIT for improving cfPWV at 12-months. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Identifier ACTRN12615000475549.

Chronic kidney disease in public renal practices in Queensland, Australia, 2011-2018.

AIM: To describe adults with (non-dialysis) chronic kidney disease (CKD) in nine public renal practice sites in the Australian state of Queensland. METHODS: 7,060 persons were recruited to a CKD Registry in May 2011 and until start of kidney replacement therapy (KRT), death without KRT or June 2018, for a median period of 3.4 years. RESULTS: The cohort comprised 7,060 persons, 52% males, with a median age of 68 yr; 85% had CKD stages 3A to 5, 45.4% were diabetic, 24.6% had diabetic nephropathy, and 51.7% were obese. Younger persons mostly had glomerulonephritis or genetic renal disease, while older persons mostly had diabetic nephropathy, renovascular disease and multiple diagnoses. Proportions of specific renal diagnoses varied >2-fold across sites. Over the first year, eGFR fell in 24% but was stable or improved in 76%. Over follow up, 10% started KRT, at a median age of 62 yr, most with CKD stages 4 and 5 at consent, while 18.8% died without KRT, at a median age of 80 yr. Indigenous people were younger at consent and more often had diabetes and diabetic kidney disease and had higher incidence rates of KRT. CONCLUSION: The spectrum of characteristics in CKD patients in renal practices is much broader than represented by the minority who ultimately start KRT. Variation in CKD by causes, age, site and Indigenous status, the prevalence of obesity, relative stability of kidney function in many persons over the short term, and differences between those who KRT and die without KRT are all important to explore.

Genome wide association study of response to interval and continuous exercise training: the Predict-HIIT study.

BACKGROUND: Low cardiorespiratory fitness (V̇O2peak) is highly associated with chronic disease and mortality from all causes. Whilst exercise training is recommended in health guidelines to improve V̇O2peak, there is considerable inter-individual variability in the V̇O2peak response to the same dose of exercise. Understanding how genetic factors contribute to V̇O2peak training response may improve personalisation of exercise programs. The aim of this study was to identify genetic variants that are associated with the magnitude of V̇O2peak response following exercise training. METHODS: Participant change in objectively measured V̇O2peak from 18 different interventions was obtained from a multi-centre study (Predict-HIIT). A genome-wide association study was completed (n = 507), and a polygenic predictor score (PPS) was developed using alleles from single nucleotide polymorphisms (SNPs) significantly associated (P < 1 × 10-5) with the magnitude of V̇O2peak response. Findings were tested in an independent validation study (n = 39) and compared to previous research. RESULTS: No variants at the genome-wide significance level were found after adjusting for key covariates (baseline V̇O2peak, individual study, principal components which were significantly associated with the trait). A Quantile-Quantile plot indicates there was minor inflation in the study. Twelve novel loci showed a trend of association with V̇O2peak response that reached suggestive significance (P < 1 × 10-5). The strongest association was found near the membrane associated guanylate kinase, WW and PDZ domain containing 2 (MAGI2) gene (rs6959961, P = 2.61 × 10-7). A PPS created from the 12 lead SNPs was unable to predict V̇O2peak response in a tenfold cross validation, or in an independent (n = 39) validation study (P > 0.1). Significant correlations were found for beta coefficients of variants in the Predict-HIIT (P < 1 × 10-4) and the validation study (P < × 10-6), indicating that general effects of the loci exist, and that with a higher statistical power, more significant genetic associations may become apparent. CONCLUSIONS: Ongoing research and validation of current and previous findings is needed to determine if genetics does play a large role in V̇O2peak response variance, and whether genomic predictors for V̇O2peak response trainability can inform evidence-based clinical practice. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR), Trial Id: ACTRN12618000501246, Date Registered: 06/04/2018, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374601&isReview=true .

The association between metabolic syndrome severity and oxidative stress induced by maximal exercise testing - a cross-sectional study.

Purpose: Oxidative stress (OS) has been implicated in the pathogenesis of metabolic syndrome (MetS). The acute change in OS biomarkers due to exercise, known as exercise-induced OS (EIOS), is postulated to be a more appropriate marker of OS compared to spot OS measures. These studies objectives were to investigate EIOS in participants with MetS and compare the associations between EIOS, spot OS measures and MetS severity. Methods: Sixty-three participants with MetS had MetS severity assessed using the MetS Z-score. Participants undertook a cardiorespiratory fitness test ( V O2peak) to volitional exhaustion (∼8-12 minutes). Plasma OS (total F2-isoprostanes (IsoP), protein carbonyls (PCs)) and antioxidant (glutathione peroxidase (GPx), total antioxidant status (TAS)) biomarkers were measured from samples obtained before and five minutes post- V O2peak test. Wilcoxon's signed-rank tests were used to determine changes in OS markers. Results: There were no significant (p > 0.05) changes in OS or antioxidant biomarkers from pre- to post-exercise (median (interquartile range): IsoP -15.5 (-71.8 to 47.8) pg/mL; PC -0.01 (-0.16 to 0.13) nmol/mg protein; GPx 0.76 (-4.94 to 9.82) U/L, TAS 0.03 (0.00-0.05) mmol/L). Conclusions: A V O2peak test to exhaustion failed to induce OS in participants with MetS. There were no associations between MetS severity and spot OS or EIOS biomarkers.

Pharmacokinetics of Enteric-Coated Mycophenolate Sodium in Lupus Nephritis (POEMSLUN).

BACKGROUND: Mycophenolate mofetil or enteric-coated mycophenolate sodium (EC-MPS) and steroids are used for induction and maintenance therapy in severe lupus nephritis. Blood concentrations of mycophenolic acid (MPA), the active metabolite of these drugs, vary among patients with lupus nephritis. The objective of this study was to examine whether concentration-controlled (CC) dosing (through therapeutic drug monitoring) of EC-MPS results in a higher proportion of participants achieving target exposure of MPA compared with fixed-dosing (FD). An additional aim of the study was to evaluate the influence of CC dosing on clinical outcomes. METHODS: Nineteen participants were randomly assigned either to the FD or CC group. All the participants were eligible to have free and total measurements of MPA over a period of 8-12 hours on 3 different occasions. Area under the concentration-time curve between 0 and 12 hours (AUC0-12) was calculated using noncompartmental methods. Dose of EC-MPS was titrated according to AUC0-12 in the CC group. RESULTS: Thirty-two AUC0-12 measurements were obtained from 9 FD and 9 CC participants. Large inter-patient variability was observed in both groups but was more pronounced in the FD group. There were no significant differences between FD and CC participants in any pharmacokinetic parameters across the study visits, except for total C0 (FD 2.0 ± 0.3 mg/L versus CC 1.1 ± 0.3; P = 0.01) and dose-normalized C0 (FD 2.9 ± 0.2 mg/L/g versus CC 2.1 ± 0.7 mg/L/g; P = 0.04) at the second visit and total AUC0-12 (FD 66.6 ± 6.0 mg·h/L versus CC 35.2 ± 11.4 mg·h/L; P = 0.03) at the third visit. At the first study visit, 33.3% of the FD and 11.1% of the CC participants achieved the target area under the concentration-time curve (P = 0.58). From the second visit, none of the FD participants, compared with all the CC participants, achieved target AUC0-12 (P = 0.01). More CC participants achieved remission compared with FD participants (absolute difference of -22.2, 95% confidence interval (Equation is included in full-text article.)0.19 to 0.55; P = 0.62). The mean free MPA AUC0-12 was significantly lower in those who had complete remission. CONCLUSIONS: CC participants reached target AUC0-12 quicker. Larger studies are required to test clinical efficacy.

High-intensity interval training in chronic kidney disease: A randomized pilot study.

INTRODUCTION: High-intensity interval training (HIIT) increases mitochondrial biogenesis and cardiorespiratory fitness in chronic disease populations, however has not been studied in people with chronic kidney disease (CKD). The aim of this study was to compare the feasibility, safety, and efficacy of HIIT with moderate-intensity continuous training (MICT) in people with CKD. METHODS: Fourteen individuals with stage 3-4 CKD were randomized to 3 supervised sessions/wk for 12 weeks, of HIIT (n = 9, 4 × 4 minute intervals, 80%-95% peak heart rate [PHR]) or MICT (n = 5, 40 minutes, 65% PHR). Feasibility was assessed via session attendance and adherence to the exercise intensity. Safety was examined by adverse event reporting. Efficacy was determined from changes in cardiorespiratory fitness (VO2 peak), exercise capacity (METs), and markers of mitochondrial biogenesis (PGC1α protein levels), muscle protein catabolism (MuRF1), and muscle protein synthesis (p-P70S6k Thr389 ). RESULTS: Participants completed a similar number of sessions in each group (HIIT = 33.0[7.0] vs MICT = 33.5[3.3] sessions), and participants adhered to the target heart rates. There were no adverse events attributable to exercise training. There was a significant time effect for exercise capacity (HIIT = +0.8 ± 1.2; MICT = +1.3 ± 1.6 METs; P = 0.01) and muscle protein synthesis (HIIT = +0.6 ± 1.1; MICT = +1.4 ± 1.7 au; P = 0.04). However, there were no significant (P > 0.05) group × time effects for any outcomes. CONCLUSION: This pilot study demonstrated that HIIT is a feasible and safe option for people with CKD, and there were similar benefits of HIIT and MICT on exercise capacity and skeletal muscle protein synthesis. These data support a larger trial to further evaluate the effectiveness of HIIT.

Chronic kidney disease, Queensland: Profile of patients with chronic kidney disease from regional Queensland, Australia: A registry report.

BACKGROUND: Chronic kidney disease, Queensland (CKD.QLD) is a multidisciplinary, collaborative research platform for CKD in Queensland. Most public renal services contribute towards the CKD Registry, including Toowoomba Hospital, which is a referral hospital for Darling Downs Health serving a largely regional population in Queensland. We aim to present the profile of the CKD cohort recruited to the CKD.QLD Registry from Toowoomba Hospital, the first comprehensive report on a pre-dialysis population from regional Australia. METHODS: Study subjects were patients in the Darling Downs Health Service who consented to be included in the CKD.QLD registry from June 2011 to December 2016. Those who were on renal replacement therapy (RRT) were excluded. Patients were followed until date of RRT, death, discharge or loss to follow up or a censor date of 30th June 2017. RESULTS: Overall 1051 subjects, representing 13% of all CKD.QLD Registry patients gave consent of whom, 42.7% were ≥70 years of age. The mean age was 63.8 ± 15.1 years (median age 67 years) with male predominance (55.4%). The majority were born in Australia (86.4%). Aboriginal and Torre Strait Islanders (A&TSI) constituted 9.6% of the cohort. The predominant CKD stages were 3b (28.9%) and 4 (27.7%). Hypertension and diabetes were noted in 91% and 44% of subjects, respectively. Diabetic nephropathy was the leading cause of CKD (26.7%) followed by renovascular disease (17.3%) and glomerulonephritis (14.8%). In 12%, the diagnosis was uncertain. Major co-morbidities included coronary artery disease (24.7%) chronic lung disease (14.8%), cerebrovascular disease (11.6%) and peripheral vascular disease (8.9%). Non-vascular co-morbidities included arthritis (24.6%), gout (23.6%) and gastro-oesophageal reflux disease (19%). The multi-morbidity profile was differed by gender, diabetic status and age. Over a follow-up period upto 72 months, 93 (8.8%) started RRT and 175 (16.6%) died. Of those 82% died without RRT and 18% died after RRT. CONCLUSION: This CKD Registry cohort from regional Queensland consisted mainly of older Caucasians with male predominance. A&TSI patients were overrepresented compared to the overall population. A significant proportion had cardio-vascular disease and multiple co-morbidities which differed by gender, diabetic status and age. This report provides valuable data for health services planning and delivery in regional Queensland.

CKD.QLD: establishment of a chronic kidney disease [CKD] registry in Queensland, Australia.

BACKGROUND: Chronic kidney disease [CKD] is recognised as a global public health problem. Until recently, the majority of information informing on CKD has been generated from renal registries reporting on patients with end-stage kidney disease [ESKD] and on renal replacement therapy [RRT]. There has been a paucity of information on pre-dialysis CKD cohorts, and many issues related to these poorly described populations are unresolved. To this end, international organizations have called for CKD surveillance systems across all countries. DESCRIPTION: In Australia, we have responded by developing the Chronic Kidney Disease in Queensland [CKD.QLD] with three main platforms consisting of CKD Registry, clinical trials and development of biobank. This registry which is the core component of CKD surveillance was conceptualized specifically for the pre-dialysis population in the public health system in Queensland, Australia. Recruitment started in May 2011, and to date the Registry has evolved as one of the largest CKD cohorts in the world with recruitment close to 7000 patients. The Registry has had many outcomes, including being the nidus for Australia's first National Health and Medical Research Council [NHMRC] CKD Centre of Research Excellence [CKD.CRE]. CONCLUSIONS: The Registry, with its linkage to Queensland Health datasets, is reporting, and is expected to continue generating, significant information on multiple aspects of CKD, its trajectory, management and patient outcomes. Intent of the CKD.CRE is to facilitate an expanded Registry network that has representation from health services, both public and private, across Australia.

The effect of different volumes of high-intensity interval training on proinsulin in participants with the metabolic syndrome: a randomised trial.

AIMS/HYPOTHESIS: The continuous demand for insulin in the face of insulin resistance, coupled with the glucolipotoxic environment associated with the metabolic syndrome (MetS), adversely affects the quality of insulin produced and secreted by the pancreatic beta cells. This is depicted by increased circulating intact proinsulin concentration, which is associated with increased MetS severity and risk of cardiovascular (CV) mortality. High-intensity interval training (HIIT) has been shown to reduce insulin resistance and other CV disease risk factors to a greater degree than moderate-intensity continuous training (MICT). We therefore aimed to investigate the impact of MICT and different volumes of HIIT on circulating intact proinsulin concentration. METHODS: This was a substudy of the 'Exercise in prevention of Metabolic Syndrome' (EX-MET) multicentre trial. Sixty-six individuals with MetS were randomised to 16 weeks of: (1) MICT (n = 21, 30 min at 60-70% peak heart rate [HRpeak], five times/week); (2) 4HIIT (n = 22, 4 × 4 min bouts at 85-95% HRpeak, interspersed with 3 min of active recovery at 50-70% HRpeak, three times/week); or (3) 1HIIT (n = 23, 1 × 4 min bout at 85-95% HRpeak, three times/week). A subanalysis investigated the differential impact of these training programmes on intact proinsulin concentration in MetS individuals with type 2 diabetes (MICT, n = 6; 4HIIT, n = 9; 1HIIT, n = 12) and without type 2 diabetes (MICT, n = 15; 4HIIT, n = 13; 1HIIT, n = 11). Intact proinsulin, insulin and C-peptide concentrations were measured in duplicate via ELISA, following a 12 h fast, before and after the exercise programme. Fasting intact proinsulin concentration was also expressed relative to insulin and C-peptide concentrations. RESULTS: Following the exercise training, there were no significant (p > 0.05) changes in fasting intact proinsulin concentration indices in all participants (pre- vs post-programme proinsulin, proinsulin:insulin, proinsulin:C-peptide: MICT 19% decrease, 6% increase, 4% increase; 4HIIT 19% decrease, 8% decrease, 11% decrease; 1HIIT 34% increase, 49% increase, 36% increase). In participants who did not have type 2 diabetes, only 4HIIT significantly (p < 0.05) reduced fasting intact proinsulin concentration indices from pre to post intervention (pre- vs post-programme proinsulin, proinsulin:insulin, proinsulin:C-peptide: 4HIIT 32% decrease, 26% decrease, 32% decrease, p < 0.05; 1HIIT, 14% increase, 32% increase, 16% increase, p > 0.05; MICT 27% decrease, 17% decrease, 11% decrease), with a group × time interaction effect, indicating a greater reduction in intact proinsulin indices following 4HIIT compared with MICT and 1HIIT. There were no significant (p > 0.05) changes in intact proinsulin concentration indices in participants with type 2 diabetes. CONCLUSIONS/INTERPRETATION: Higher-volume HIIT (4HIIT) improved insulin quality in MetS participants without type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT01676870 FUNDING: The study was funded by the Norwegian University of Science and Technology and from an unrestricted research grant from the Coca-Cola company. Funding for the collection of physical activity data was derived from a 'UQ New Staff Start Up' grant awarded to B. Clark.

Identifying and integrating consumer perspectives in clinical practice guidelines on autosomal-dominant polycystic kidney disease.

AIM: This study aimed to identify consumer perspectives on topics and outcomes to integrate in the Kidney Health Australia Caring for Australasians with Renal Impairment (KHA-CARI) clinical practice guidelines on autosomal-dominant polycystic kidney disease (ADPKD). METHODS: A workshop involving three concurrent focus groups with 18 consumers (patients with ADPKD (n = 15), caregivers (n = 3)) was convened. Guideline topics, interventions and outcomes were identified, and integrated into guideline development. Thematic analysis was used to analyse the reasons for their choices. RESULTS: Twenty-two priority topics were identified, with most focussed on non-pharmacological management (diet, fluid intake, physical activity, complementary medicine), pain management and psychosocial care (mental health, counselling, cognitive and behavioural training, education, support groups). They also identified 26 outcomes including quality of life (QoL), progression of kidney disease, kidney function, cyst growth and nephrotoxity. Almost all topics and outcomes suggested were identified by health professionals with the exception of five topics/outcomes. Six themes reflected reasons for their choices: clarifying ambiguities, resolving debilitating pain, concern for family, preparedness for the future, taking control and significance of impact. CONCLUSION: Although there was considerable concordance between the priority topics and outcomes of health professionals and consumers for guidelines of ADPKD, there was also important discordance with consumers focused on fewer issues, but particularly on lifestyle, psychosocial support, pain, and QoL and renal outcomes. Active consumer engagement in guidelines development can help to ensure the inclusion of patient-centred recommendations, which may lead to better management of disease progression, symptoms, complications, and psychosocial impact.

Effects of atorvastatin on oxidative stress in chronic kidney disease.

AIM: Statins have pleiotropic effects that include attenuation of oxidative stress that may be relevant for chronic kidney disease (CKD) patients. We investigated the effect of long-term atorvastatin therapy on oxidative stress biomarkers in CKD patients. METHODS: This was a pre-specified secondary analysis of data from a randomized, double-blind, placebo-controlled trial (Lipid lowering and Onset of Renal Disease, LORD) in CKD patients. Participants received 10 mg/day atorvastatin (n = 47) or placebo (n = 39) for 3 years. Plasma measures (total F2-isoprostanes, malondialdehyde. protein carbonyls, uric acid, glutathione peroxidase (GPx) activity and total antioxidant capacity (TAC) ) were performed at baseline and at 3 years. Age and sex matched participants (n = 34) with normal kidney function were controls. RESULTS: CKD patients had significantly (P < 0.05) increased F2-isoprostanes and uric acid and decreased GPx activity compared with controls. When comparing the treatment (atorvastatin (A) vs placebo (P) ) change from baseline to 3 years, there were no significant differences (P > 0.05) in the group difference of the change values: (mean (95% CI), F2-isoprostanes = 5.3 (-29.2 to 39.8) pg/mL, protein carbonyls = 0.03 (-0.13 to 0.19) nmol/mg, GPx activity = -0.10 (-4.73 to 4.52) (U/L), uric acid = 8.8 (-33.9 to 51.6) µmol/L or TAC = -0.03 (-0.10 to 0.04) mmol/L. A significant difference (P = 0.04) in the change in malondialdehyde between groups, 1.52(0.09 to 2.96) µmol/L, was due to a large decrease in the placebo group. CONCLUSION: CKD patients had elevated oxidative stress that was not attenuated by atorvastatin 10 mg/day for 3 years.

Optimal criteria and sampling interval to detect a V̇O2 plateau at V̇O2max in patients with metabolic syndrome.

This study sought to determine the optimal criteria and sampling interval to detect a V̇O2 plateau at V̇O2max in patients with metabolic syndrome. Twenty-three participants with criteria-defined metabolic syndrome underwent a maximal graded exercise test. Four different sampling intervals and three different V̇O2 plateau criteria were analysed to determine the effect of each parameter on the incidence of V̇O2 plateau at V̇O2max. Seventeen tests were classified as maximal based on attainment of at least two out of three criteria. There was a significant (p < 0.05) effect of 15-breath (b) sampling interval on the incidence of V̇O2 plateau at V̇O2max across the ≤ 50 and ≤ 80 mL ∙ min(-1) conditions. Strength of association was established by the Cramer's V statistic (φc); (≤ 50 mL ∙ min(-1) [φc = 0.592, p < 0.05], ≤ 80 mL ∙ min(-1) [φc = 0.383, p < 0.05], ≤ 150 mL ∙ min(-1) [φc = 0.246, p > 0.05]). When conducting maximal stress tests on patients with metabolic syndrome, a 15-b sampling interval and ≤ 50 mL ∙ min(-1) criteria should be implemented to increase the likelihood of detecting V̇O2 plateau at V̇O2max.

Circulating bilirubin and defense against kidney disease and cardiovascular mortality: mechanisms contributing to protection in clinical investigations.

Unconjugated bilirubin is an endogenous circulating antioxidant, bound to albumin, and therefore is retained in the vascular compartment. Bilirubin has well-documented neurotoxic effects in infants; however, current evidence indicates mildly elevated bilirubin is associated with protection from cardiovascular disease and all-cause mortality in adults. Recent clinical studies show mildly elevated bilirubin is associated with protection from kidney damage and dysfunction, in addition to cardiovascular events and all-cause mortality in patients undergoing hemodialysis. This is the first review to examine the clinical evidence and summarize the potential mechanisms of action that link bilirubin to protection from kidney damage, subsequent kidney failure, and dialysis-related mortality. With this understanding, it is hoped that new therapies will be developed to prevent renal dysfunction and mortality from cardiovascular disease in at-risk individuals.

Taming the chronic kidney disease epidemic: a global view of surveillance efforts.

Chronic kidney disease is now recognized to be a worldwide problem associated with significant morbidity and mortality and there is a steep increase in the number of patients reaching end-stage renal disease. In many parts of the world, the disease affects younger people without diabetes or hypertension. The costs to family and society can be enormous. Early recognition of CKD may help prevent disease progression and the subsequent decline in health and longevity. Surveillance programs for early CKD detection are beginning to be implemented in a few countries. In this article, we will focus on the challenges and successes of these programs with the hope that their eventual and widespread use will reduce the complications, deaths, disabilities, and economic burdens associated with CKD worldwide.

Effects of uric acid-lowering therapy on renal outcomes: a systematic review and meta-analysis.

BACKGROUND: Non-randomized studies suggest an association between serum uric acid levels and progression of chronic kidney disease (CKD). The aim of this systematic review is to summarize evidence from randomized controlled trials (RCTs) concerning the benefits and risks of uric acid-lowering therapy on renal outcomes. METHODS: Medline, Excerpta Medical Database and Cochrane Central Register of Controlled Trials were searched with English language restriction for RCTs comparing the effect of uric acid-lowering therapy with placebo/no treatment on renal outcomes. Treatment effects were summarized using random-effects meta-analysis. RESULTS: Eight trials (476 participants) evaluating allopurinol treatment were eligible for inclusion. There was substantial heterogeneity in baseline kidney function, cause of CKD and duration of follow-up across these studies. In five trials, there was no significant difference in change in glomerular filtration rate from baseline between the allopurinol and control arms [mean difference (MD) 3.1 mL/min/1.73 m2, 95% confidence intervals (CI) -0.9, 7.1; heterogeneity χ2=1.9, I2=0%, P=0.75]. In three trials, allopurinol treatment abrogated increases in serum creatinine from baseline (MD -0.4 mg/dL, 95% CI -0.8, -0.0 mg/dL; heterogeneity χ2=3, I2=34%, P=0.22). Allopurinol had no effect on proteinuria and blood pressure. Data for effects of allopurinol therapy on progression to end-stage kidney disease and death were scant. Allopurinol had uncertain effects on the risks of adverse events. CONCLUSIONS: Uric acid-lowering therapy with allopurinol may retard the progression of CKD. However, adequately powered randomized trials are required to evaluate the benefits and risks of uric acid-lowering therapy in CKD.

Variability of oxidative stress biomarkers in hemodialysis patients.

Oxidative stress biomarkers may have a role in the future to assist clinical decisions regarding the use of antioxidant therapies and their efficacy. The aims of this study were to evaluate the within and between-individual variability of plasma oxidative stress biomarkers and investigate factors affecting their variability. Plasma F2-isoprostanes and protein carbonyls were measured in 14 hemodialysis patients every 2 weeks for 10 weeks. Within-individual coefficients of variation (CVs) were isoprostanes = 30.4% (range = 6.1-66.7%) and protein carbonyls = 16.3% (8.4-29.5%). Between-individual CVs were isoprostanes = 34.4% (28.9-40.2%) and protein carbonyls = 19.5% (15.6-24.5%). There were no significant (p > 0.05) relationships between the oxidative stress biomarkers and dietary antioxidant intake, medications, clinical and demographic parameters.

Effects of atorvastatin on biomarkers of inflammation in chronic kidney disease.

BACKGROUND: Chronic kidney disease (CKD) is associated with inflammation. The effects of atorvastatin on biomarkers of inflammation were assessed in CKD patients in the LORD trial. METHODS: 117 patients with serum creatinine >120 µmol/L were randomized to receive atorvastatin 10 mg/day (56) or placebo (61) and followed for a mean of 2.5 years. 33 individuals with normal kidney function were controls. Outcomes included comparison of changes in pentraxin-3 (PTX3), TNF-α, CRP, IL-6, IL-8, and IL-10 between atorvastatin and placebo-treated patients. RESULTS: At baseline, compared with controls, CKD patients had increased PTX3 (mean, 1.08 vs. 0.58 ng/mL; p < 0.001), CRP (4.9 vs. 1.5 mg/L; p < 0.001), IL-8 (6.00 vs. 4.58 pg/mL; p = 0.001), IL-10 (59.0 vs. 17.6 pg/mL; p = 0.007), and TNF-α (18.0 vs. 5.6 ng/mL; p < 0.001). In patients with raised baseline plasma IL-6/8/10 and/or PTX3 the eGFR decline during the trial was significantly less in those treated with atorvastatin compared to placebo (mean change, -3.36; vs. + 1.25 mL/min/1.73 m2/year; difference, 4.61 95% CI 0.98 - 8.25; p = 0.002), whilst those without raised inflammatory biomarkers showed no difference. Placebo treated patients with raised TNF-α levels had no eGFR decline (p > 0.90), whereas in atorvastatin-treated patients eGFR declined (p = 0.05). CONCLUSIONS: CKD patients with inflammation treated with atorvastatin had significantly less eGFR decline. Larger studies using statin therapy, specifically enrolling CKD patients with inflammation, may be worthwhile exploring.

Targets, trends, excesses, and deficiencies: refocusing clinical investigation to improve patient outcomes.

Clinical trials in nephrology have focused on achieving targets, supplementing deficiencies, and correcting excesses in order to improve patient outcomes. The majority of interventions have failed to demonstrate benefit and some have caused harm. It may be that therapies aiming to 'normalize' parameters may actually disturb evolutionary adaptation, thus causing harm. By refocusing on the physiology of disease, and complexity of adaptation, we may design better trials. We review successful and unsuccessful trials in nephrology and other disciplines and suggest a set of principles by which to design future clinical trials:(1) acknowledge heterogeneity of chronic kidney disease populations and appropriately characterize populations for studies; (2) develop better validated biomarkers (through proteomics, genomics, and metabolomics) to identify responders and nonresponders to interventions; (3) design interventions that mimic physiological processes without collateral detrimental effects; (4) reconsider the status of the randomized-controlled trial as the only 'gold standard' and perform large-scale pragmatic trials comparing current care with the intervention(s) of interest, and (5) broaden nephrology research culture so that the majority of patients are enrolled into observational cohorts and intervention studies, which foster greater knowledge acquisition and dissemination. Improved understanding of pathophysiological mechanisms, in conjunction with more innovative but stringent clinical trial design, will ultimately lead to improved patient outcomes.

Variability in oxidative stress biomarkers following a maximal exercise test.

The oxidative stress response to maximal exercise may provide useful clinical biomarkers for assessing redox homeostasis. The aim was to determine the between-individual variability in the exercise-induced change in oxidative stress measures and investigate predictors of these responses. Plasma F2-isoprostanes (Isop), protein carbonyls (PCs), glutathione peroxidase (GPX) activity and total antioxidant capacity (TAC) were measured before and after a maximal treadmill exercise test. Exercise produced significant increases in Isop (27.0%), PC (6.2%) and GPX (7.8%). There were large between-individual coefficients of variation: Isop (152%), PC, (240%), GPX (130%) and TAC (243%).

Research issues in Elderly patients: gaps in knowledge and suggested directions.

Concentration of research is recommended in the following areas: Prospective studies of the appropriateness, relevance, timing and sustainability of dialysis in elderly patients Health related quality of life (HRQoL) in older patients choosing not to dialyse and in those choosing to dialyse with comparison to a matched population without renal disease Methods of communication of prognosis and factors affecting decision making Models of care - comparative studies to delineate how best to deliver renal supportive care Treatment preferences amongst indigenous patients Symptom control, focussing on those areas specific to the needs of renal patients.