Extraction of high quality and high yield RNA from frozen EDTA blood.

Peripheral blood RNA profiling, which can reveal systemic changes in gene expression and immune responses to disease onset and progression, is a powerful tool for diagnosis and biomarker discovery. This technique usually requires high quality RNA, which is only obtainable from fresh blood, or frozen blood that has been collected in special RNA-stabilisation systems. The current study aimed to develop a novel protocol to extract high quality RNA from frozen blood that had been collected in the conventional EDTA tubes. We determined that thawing EDTA blood in the presence of cell lysis/RNA stabilisation buffers (Paxgene or Nucleospin) significantly improved RNA quality (RIN) from below 5 to above 7, which to date has not been shown possible. The EDTA-Nucleospin protocol resulted in 5 times higher yield than the EDTA-Paxgene-PreAnalytix method. The average RIN and mRNA expression levels of five different genes including 18 s, ACTB, MCP1, TNFa and TXNIP using this protocol were also indifferent to those from Paxgene blood, suggesting similar RNA quality and blood transcriptome. Moreover, the protocol allows DNA to be extracted simultaneously. In conclusion, we have developed a practical and efficient protocol to extract high quality, high yield RNA from frozen EDTA blood.

A new era in the science and care of kidney diseases.

Notable progress in basic, translational and clinical nephrology research has been made over the past five decades. Nonetheless, many challenges remain, including obstacles to the early detection of kidney disease, disparities in access to care and variability in responses to existing and emerging therapies. Innovations in drug development, research technologies, tissue engineering and regenerative medicine have the potential to improve patient outcomes. Exciting prospects include the availability of new drugs to slow or halt the progression of chronic kidney disease, the development of bioartificial kidneys that mimic healthy kidney functions, and tissue engineering techniques that could enable transplantable kidneys to be created from the cells of the recipient, removing the risk of rejection. Cell and gene therapies have the potential to be applied for kidney tissue regeneration and repair. In addition, about 30% of kidney disease cases are monogenic and could potentially be treated using these genetic medicine approaches. Systemic diseases that involve the kidney, such as diabetes mellitus and hypertension, might also be amenable to these treatments. Continued investment, communication, collaboration and translation of innovations are crucial to realize their full potential. In addition, increasing sophistication in exploring large datasets, implementation science, and qualitative methodologies will improve the ability to deliver transformational kidney health strategies.

Intra-operative duplex ultrasound scanning in renal transplantation: protocol and service requirements.

Intra-operative duplex ultrasound in renal transplantation was first described in 1998 and whilst reported in problematic cases, there are few reports of its routine use and no current published protocols. Since 2013, we have used intra-operative ultrasound in all renal transplants. The formal protocol used since August 2020 is presented as a reference document for other transplant centres. A Canon Aplio 800 ultrasound system with an i22LH8 hockey-stick transducer is used to image the renal cortex and major vessels, and an i8CX1 matrix transducer to image the graft during and after fascial closure. These transducers are fully sterilised with Sterrad and no sheathing of transducers is required. The transplant surgeon scans within the sterile field with the sonographer guiding imaging and adjusting machine settings. Ultrasound findings are discussed between team members including any requirement for interventions. Ultrasound is performed at three stages of the operation: Stage 1: after clamp release identifying issues of graft vascularity including otherwise unrecognised major vessel and anastomotic abnormalities. Stage 2: following ureteric implantation identifying compromised perfusion due to graft rotation or vessel kinking. Stage 3: after fascial closure identifying compromised perfusion due to external compression. Post-operative scanning, including assessment of the collecting system and bladder, is performed routinely on days 1, 3, 7 and 30. The intervention is effective with no early graft losses or peri-operative vascular thromboses. The requirements for service provision are significant including the availability of additional transducers, and sonographers with expertise in intra-operative scanning able to attend after-hours for extended periods.

Results from a cross-specialty consensus on optimal management of patients with chronic kidney disease (CKD): from screening to complications.

BACKGROUND: Chronic kidney disease (CKD) affects around 10% of the global population and has been estimated to affect around 50% of individuals with type 2 diabetes and 50% of those with heart failure. The guideline-recommended approach is to manage with disease-modifying therapies, but real-world data suggest that prescribing rates do not reflect this in practice. OBJECTIVE: To develop a cross-specialty consensus on optimal management of the patient with CKD using a modified Delphi method. DESIGN: An international steering group of experts specialising in internal medicine, endocrinology/diabetology, nephrology and primary care medicine developed 42 statements on aspects of CKD management including identification and screening, risk factors, holistic management, guidelines, cross-specialty alignment and education. Consensus was determined by agreement using an online survey. PARTICIPANTS: The survey was distributed to cardiologists, nephrologists, endocrinologists and primary care physicians across 11 countries. MAIN OUTCOMES AND MEASURES: The threshold for consensus agreement was established a priori by the steering group at 75%. Stopping criteria were defined as a target of 25 responses from each country (N=275), and a 4-week survey period. RESULTS: 274 responses were received in December 2022, 25 responses from Argentina, Australia, Brazil, Guatemala, Mexico, Singapore, South Korea, Taiwan, Thailand, Turkey and 24 responses from Egypt. 53 responses were received from cardiologists, 52 from nephrologists, 55 from endocrinologists and 114 from primary care physicians. 37 statements attained very high agreement (≥90%) and 5 attained high agreement (≥75% and <90%). Strong alignment between roles was seen across the statements, and different levels of experience (2-5 years or 5+ years), some variation was observed between countries. CONCLUSIONS: There is a high degree of consensus regarding aspects of CKD management among healthcare professionals from 11 countries. Based on these strong levels of agreement, the steering group derived 12 key recommendations focused on diagnosis and management of CKD.

Autoantibodies to Erythropoietin Receptor and Clinical Outcomes in Patients With Type 2 Diabetes and CKD: A Post Hoc Analysis of CREDENCE Trial.

Introduction: Autoantibodies to erythropoietin receptor (anti-EPOR antibodies) have been identified in patients with various kidney diseases. However, data in patients with type 2 diabetes (T2D) and chronic kidney disease (CKD) is limited. We assessed the prevalence of anti-EPOR antibodies and their association with clinical outcomes in this population. Methods: The CREDENCE randomized patients with T2D and CKD to canagliflozin or placebo. Serum anti-EPOR antibodies, the exposure of interest, were measured using enzyme-linked immunosorbent assay. The primary outcome was doubling of serum creatinine, end-stage kidney disease, or death from kidney or cardiovascular (CV) causes. Secondary outcomes included CV and all-cause mortality. Multivariable Cox-regression models estimated associations between anti-EPOR antibodies and outcomes. The effects of canagliflozin on hemoglobin and hematocrit, stratified by the presence of anti-EPOR antibodies were assessed with a repeated measures mixed effects model. Results: Of 2600 participants with available biosamples, 191 (7.3%) were positive for anti-EPOR antibodies. Higher baseline anti-EPOR antibodies were associated with increased risk of primary outcome (hazard ratio [HR] per 1-SD increase = 1.12, 95% confidence interval [CI] = 1.01-1.24, P = 0.04), with CV death (HR = 1.27, 95% CI = 1.08-1.48, P < 0.01) and all-cause mortality (HR = 1.26, 95% CI = 1.11-1.43, P < 0.01). During follow-up, canagliflozin, compared to placebo, increased hemoglobin and hematocrit by 7.0 g/l (95% CI = 6.2-7.9) and 2.4% (2.2-2.7), respectively. These effects were consistent across patients with and without anti-EPOR antibodies (P-interaction = 0.24 and 0.36, respectively). Conclusion: In patients with T2D and CKD, anti-EPOR antibodies were associated with the composite kidney and CV outcome, as well as CV and all-cause mortality. Canagliflozin increased hemoglobin and hematocrit regardless of anti-EPOR antibodies.

Vascular endothelial growth factors and risk of cardio-renal events: Results from the CREDENCE trial.

BACKGROUND: Circulating concentrations of vascular endothelial growth factor (VEGF) family members may be abnormally elevated in type 2 diabetes (T2D). The roles of placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFLT-1), and VEGF-A in cardio-renal complications of T2D are not established. METHOD: The 2602 individuals with diabetic kidney disease (DKD) from the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation trial were randomized to receive canagliflozin or placebo and followed for incident cardio-renal outcomes. PlGF, sFLT-1, and VEGF-A were measured at baseline, year 1, and year 3. Primary outcome was a composite of end-stage kidney disease, doubling of the serum creatinine, or renal/cardiovascular death. Cox proportional hazard regression was used to investigate the association between biomarkers with adverse clinical events. RESULTS: At baseline, individuals with higher PlGF levels had more prevalent cardiovascular disease compared to those with lower values. Treatment with canagliflozin did not meaningfully change PlGF, sFLT-1, and VEGF-A concentrations at years 1 and 3. In a multivariable model, 1 unit increases in baseline log PlGF (hazard ratio [HR]: 1.76, 95% confidence interval [CI]: 1.23, 2.54, P-value = .002), sFLT-1 (HR: 3.34, [95% CI: 1.71, 6.52], P-value < .001), and PlGF/sFLT-1 ratio (HR: 4.83, [95% CI: 0.86, 27.01], P-value = .07) were associated with primary composite outcome, while 1 unit increase in log VEGF-A did not increase the risk of primary outcome (HR: 0.96 [95% CI: 0.81, 1.07]). Change by 1 year of each biomarker was also assessed: HR (95% CI) of primary composite outcome was 2.45 (1.70, 3.54) for 1 unit increase in 1-year concentration of log PlGF, 4.19 (2.18, 8.03) for 1 unit increase in 1-year concentration of log sFLT-1, and 21.08 (3.79, 117.4) for 1 unit increase in 1-year concentration of log PlGF/sFLT-1. Increase in 1-year concentrations of log VEGF-A was not associated with primary composite outcome (HR: 1.08, [95% CI: 0.93, 1.24], P-value = .30). CONCLUSIONS: People with T2D and DKD with elevated levels of PlGF, sFLT-1, and PlGF/sFLT-1 ratio were at a higher risk for cardiorenal events. Canagliflozin did not meaningfully decrease concentrations of PlGF, sFLT-1, and VEGF-A. CLINICAL TRIAL: CREDENCE, https://clinicaltrials.gov/ct2/show/NCT02065791.

Glucose-lowering treatment pathways of individuals with chronic kidney disease and type 2 diabetes according to the Kidney Disease: Improving Global Outcomes 2012 risk classification.

AIMS: To describe treatment pathways for key glucose-lowering therapies in individuals with chronic kidney disease (CKD) and type 2 diabetes (T2D) using retrospective data from DISCOVER CKD (NCT04034992). METHODS: Data were extracted from the UK Clinical Practice Research Datalink (CPRD) linked to Hospital Episode Statistics data (2008-2020) and the US integrated Limited Claims and Electronic Health Records Database (LCED; 2012-2019). Eligible individuals were aged ≥18 years with CKD, identified by two consecutive estimated glomerular filtration rate (eGFR) measures (15-<75 mL/min/1.73 m2 ; 90-730 days apart; index date was the second measurement) and T2D. Chronological treatment pathways for glucose-lowering therapies prescribed on or after CKD index to end of follow-up were computed. Median time and proportion of overall follow-up time on treatment were described for each therapy by database and by eGFR and urinary albumin-to-creatinine ratio (UACR) categories. RESULTS: Of 36,951 and 4339 eligible individuals in the CPRD and LCED, respectively, median baseline eGFR was 67.8 and 64.9 mL/min/1.73 m2 ; 64.2 and 63.9% received metformin prior to index; and median (interquartile range) time on metformin during follow-up was 917 (390-1671) and 454 (192-850) days (accounting for ~75% of follow-up time in both databases). The frequency of combination treatment increased over time. There were trends towards decreased metformin prescriptions with decreasing eGFR and increasing UACR within each eGFR category. CONCLUSIONS: Individuals with CKD and T2D had many combinations of therapies and substantial follow-up time on therapy. These results highlight opportunities for improved CKD management.

Associations of Angiopoietin 2 and Vascular Endothelial Growth Factor-A Concentrations with Clinical End Points.

BACKGROUND: Angiopoietin 2 regulates endothelial function partially mediated by vascular endothelial growth factor-A (VEGF-A) and may play a role in diabetic kidney disease (DKD). We assessed the association of angiopoietin 2 and VEGF-A with cardiorenal outcomes and investigated the effect of canagliflozin on angiopoietin 2 and VEGF-A concentrations. METHODS: Two thousand five hundred sixty-five study participants with DKD and available plasma samples treated with canagliflozin or placebo in the Canagliflozin and Kidney Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial were included. Angiopoietin 2 and VEGF-A concentrations were measured at baseline, year 1, and year 3. The primary composite end point of the trial was a composite of kidney failure, doubling of the serum creatinine level, and kidney or cardiovascular death. RESULTS: Patients with the highest baseline quartile of angiopoietin 2, but not VEGF-A, concentration had the highest risk clinical profile. Treatment with canagliflozin significantly lowered concentrations of angiopoietin 2 (adjusted geometric mean ratio: 0.94; 95% confidence interval, 0.92 to 0.95; P < 0.001), but not VEGF-A. In multivariable-adjusted modeling, each 50% increment in log baseline angiopoietin 2 concentrations was associated with a higher risk of primary composite outcome (hazard ratio, 1.27; 95% confidence interval, 1.13 to 1.43). Angiopoietin 2 change at year 1 compared with baseline explained 10% of the effect of canagliflozin on the primary composite outcome. VEGF-A concentrations were not associated with outcomes, alone or in combination with angiopoietin 2. CONCLUSIONS: Higher angiopoietin 2 levels were associated with cardiorenal risk among individuals with DKD independent of VEGF-A. Canagliflozin lowered angiopoietin 2 concentrations. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Evaluation of the Effects of Canagliflozin on Renal and Cardiovascular Outcomes in Participants With Diabetic Nephropathy, NCT02065791 .

Effects of dapagliflozin and dapagliflozin-saxagliptin on erythropoiesis, iron and inflammation markers in patients with type 2 diabetes and chronic kidney disease: data from the DELIGHT trial.

BACKGROUND: This post-hoc analysis of the DELIGHT trial assessed effects of the SGLT2 inhibitor dapagliflozin on iron metabolism and markers of inflammation. METHODS: Patients with type 2 diabetes and albuminuria were randomized to dapagliflozin, dapagliflozin and saxagliptin, or placebo. We measured hemoglobin, iron markers (serum iron, transferrin saturation, and ferritin), plasma erythropoietin, and inflammatory markers (urinary MCP-1 and urinary/serum IL-6) at baseline and week 24. RESULTS: 360/461 (78.1%) participants had available biosamples. Dapagliflozin and dapagliflozin-saxagliptin, compared to placebo, increased hemoglobin by 5.7 g/L (95%CI 4.0, 7.3; p < 0.001) and 4.4 g/L (2.7, 6.0; p < 0.001) and reduced ferritin by 18.6% (8.7, 27.5; p < 0.001) and 18.4% (8.7, 27.1; p < 0.001), respectively. Dapagliflozin reduced urinary MCP-1/Cr by 29.0% (14.6, 41.0; p < 0.001) and urinary IL-6/Cr by 26.6% (9.1, 40.7; p = 0.005) with no changes in other markers. CONCLUSIONS: Dapagliflozin increased hemoglobin and reduced ferritin and urinary markers of inflammation, suggesting potentially important effects on iron metabolism and inflammation. TRIAL REGISTRATION: ClinicalTrials.gov NCT02547935.

Nutrition and Developmental Origins of Kidney Disease.

The developmental programming hypothesis proposes that adverse environmental insults during critical developmental periods increase the risk of diseases later in life. The kidneys are deemed susceptible to such a process, although the exact mechanisms remain elusive. Many factors have been reported to contribute to the developmental origin of chronic kidney diseases (CKD), among which peri-gestational nutrition has a central role, affecting kidney development and metabolism. Physiologically, the link between malnutrition, reduced glomerular numbers, and increased blood pressure is key in the developmental programming of CKD. However, recent studies regarding oxidative stress, mitochondrial dysfunction, epigenetic modifications, and metabolic changes have revealed potential novel pathways for therapeutic intervention. This review will discuss the role of imbalanced nutrition in the development of CKD.

Cardiorenal Biomarkers, Canagliflozin, and Outcomes in Diabetic Kidney Disease: The CREDENCE Trial.

BACKGROUND: People with type 2 diabetes and albuminuria are at an elevated risk for cardiac and renal events. The optimal biomarkers to aid disease prediction and to understand the benefits of sodium-glucose cotransporter-2 inhibition remain unclear. METHODS: Among 2627 study participants in the CREDENCE trial (Canagliflozin and Renal Events in Diabetes With Established Nephropathy Clinical Evaluation), concentrations of NT-proBNP (N-terminal pro-B-type natriuretic peptide), high-sensitivity cardiac troponin T, growth differentiation factor-15, and IGFBP7 (insulin-like growth factor binding protein 7) were measured. The effect of canagliflozin on biomarker concentrations was evaluated. The prognostic potential of each biomarker on the primary outcome (a composite of end-stage kidney disease [dialysis, transplantation, or a sustained estimated glomerular filtration rate of <15 mL·min-1·1.73 m-2], doubling of the serum creatinine level, or renal death or cardiovascular death) was assessed. RESULTS: The median (quartiles 1 and 3) concentration of each biomarker was generally elevated: NT-proBNP, 180 ng/L (82, 442 ng/L); high-sensitivity cardiac troponin T, 19 ng/L (12, 29 ng/L); growth differentiation factor-15, 2595 ng/L (1852, 3775 ng/L); and IGFBP7, 121.8 ng/mL (105.4, 141.5 ng/mL). At 1 year, the biomarkers all rose by 6% to 29% in the placebo arm but only by 3% to 10% in the canagliflozin arm (all P<0.01 in multivariable linear mixed-effect models). Baseline concentrations of each biomarker were strongly predictive of cardiac and renal outcomes. When the biomarkers were analyzed together in a multimarker panel, individuals with high risk scores (hazard ratio [HR], 4.01 [95% CI, 2.52-6.35]) and moderate risk scores (HR, 2.39 [95% CI, 1.48-3.87]) showed a higher risk for the primary outcome compared with those with low risk scores. By 1 year, a 50% increase in NT-proBNP (HR, 1.11 [95% CI, 1.08-1.15]), high-sensitivity cardiac troponin T (HR, 1.86 [95% CI, 1.64-2.10]), growth differentiation factor-15 (HR, 1.45 [95% CI, 1.24-1.70]), and IGFBP7 (HR, 3.76 [95% CI, 2.54-5.56]) was associated with risk of the primary outcome. CONCLUSIONS: Multiple cardiorenal stress biomarkers are strongly prognostic in people with type 2 diabetes and albuminuria. Canagliflozin modestly reduced the longitudinal trajectory of rise in each biomarker. Change in the biomarker level in addition to the baseline level augments the primary outcome prediction. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02065791.

Effect of E-Vaping on Kidney Health in Mice Consuming a High-Fat Diet.

High-fat diet (HFD) consumption and tobacco smoking are risk factors for chronic kidney disease. E-cigarettes have gained significant popularity among younger populations worldwide, especially among overweight individuals. It is unclear whether vaping interacts with HFD consumption to impact renal health. In this study, Balb/c mice (male, 7 weeks old) were fed a pellet HFD (43% fat, 20 kJ/g) for 16 weeks when exposed to nicotine or nicotine-free e-vapour from weeks 11 to 16. While HFD alone increased collagen Ia and IV depositions, it did not cause significant oxidative stress and inflammatory responses in the kidney itself. On the other hand, e-vapour exposure alone increased oxidative stress and damaged DNA and mitochondrial oxidative phosphorylation complexes without significant impact on fibrotic markers. However, the combination of nicotine e-vapour and HFD increased inflammatory responses, oxidative stress-induced DNA injury, and pro-fibrotic markers, suggesting accelerated development of renal pathology. Nicotine-free e-vapour exposure and HFD consumption suppressed the production of mitochondrial OXPHOS complexes and extracellular matrix protein deposition, which may cause structural instability that can interrupt normal kidney function in the future. In conclusion, our study demonstrated that a HFD combined with e-cigarette vapour exposure, especially when containing nicotine, can increase susceptibility to kidney disease.

Insulin growth factor axis and cardio-renal risk in diabetic kidney disease: an analysis from the CREDENCE trial.

BACKGROUND: The insulin-like growth factors (IGF) play a crucial role in regulating cellular proliferation, apoptosis, and key metabolic pathways. The ratio of IGF-1 to IGF binding protein-3 (IGFBP-3) is an important factor in determining IGF-1 bioactivity. We sought to investigate the association of IGF-1 and IGFBP-3 with cardio-renal outcomes among persons with type 2 diabetes. METHODS: Samples were available from 2627 individuals with type 2 diabetes and chronic kidney disease that were randomized to receive canagliflozin or placebo and were followed up for incident cardio-renal events. Primary outcome was defined as a composite of end-stage kidney disease, doubling of the serum creatinine level, or renal/cardiovascular death. IGF-1 and IGFBP-3 were measured at baseline, Year-1 and Year-3. Elevated IGF-1 level was defined according to age-specific cutoffs. Cox proportional hazard regression was used to investigate the association between IGF-1 level, IGFBP-3, and the ratio of IGF-1/IGFBP-3 with clinical outcomes. RESULTS: Elevated IGF-1 was associated with lower glomerular filtration rate at baseline. Treatment with canagliflozin did not significantly change IGF-1 and IGFBP-3 concentrations by 3 years (p-value > 0.05). In multivariable models, elevated IGF-1 (above vs below age-specific cutoffs) was associated with the primary composite outcome (incidence rate:17.8% vs. 12.7% with a hazard ratio [HR]: 1.52; 95% confidence interval CI 1.09-2.13;P: 0.01), renal composite outcome (HR: 1.65; 95% CI 1.14-2.41; P: 0.01), and all-cause mortality (HR: 1.52; 95% CI 1.00-2.32; P; 0.05). Elevations in log IGFBP-3 did not associate with any clinical outcomes. Increase in log IGF-1/IGFBP-3 ratio was also associated with a higher risk of the primary composite outcome (HR per unit increase: 1.57; 95% CI 1.09-2.26; P; 0.01). CONCLUSIONS: These results further suggest potential importance of IGF biology in the risk for cardio-renal outcomes in type 2 diabetes. SGLT2 inhibition has no impact on the biology of IGF despite its significant influence on outcomes. TRIAL REGISTRATION: CREDENCE; ClinicalTrials.gov Identifier: NCT02065791.

Canagliflozin, Blood Pressure Variability, and Risk of Cardiovascular, Kidney, and Mortality Outcomes: Pooled Individual Participant Data From the CANVAS and CREDENCE Trials.

Background Sodium glucose cotransporter-2 inhibitors reduce systolic blood pressure (SBP), but whether they affect SBP variability is unknown. There also remains uncertainty regarding the prognostic value of SBP variability for different clinical outcomes. Methods and Results Using individual participant data from the CANVAS (Canagliflozin Cardiovascular Assessment Study) Program and CREDENCE (Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation) trial, we assessed the effect of canagliflozin on SBP variability in people with type 2 diabetes across 4 study visits over 1.5 years as measured by standard deviation, coefficient of variation, and variability independent of the mean. We used multivariable Cox regression models to estimate associations of SBP variability with cardiovascular, kidney, and mortality outcomes. In 11 551 trial participants, canagliflozin modestly lowered the standard deviation of SBP variability (-0.25 mm Hg [95% CI, -0.44 to -0.06]), but there was no effect on coefficient of variation (0.02% [95% CI, -0.12 to 0.16]) or variability independent of the mean (0.08 U [95% CI, -0.11 to 0.26]) when adjusting for correlation with mean SBP. Each 1 standard deviation increase in standard deviation of SBP variability was independently associated with higher risk of hospitalization for heart failure (hazard ratio [HR], 1.19 [95% CI, 1.02-1.38]) and all-cause mortality (HR, 1.12 [95% CI, 1.01-1.25]), with consistent results observed for coefficient of variation and variability independent of the mean. Increases in SBP variability were not associated with kidney outcomes. Conclusions In people with type 2 diabetes at high cardiovascular risk or with chronic kidney disease, higher visit-to-visit SBP variability is independently associated with risks of hospitalization for heart failure and all-cause mortality. Canagliflozin has little to no effect on SBP variability, independent of its established SBP-lowering effect. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01032629, NCT01989754, NCT02065791.

Cardiorenal protective effects of canagliflozin in CREDENCE according to glucose lowering.

INTRODUCTION: Relationships between glycemic-lowering effects of sodium glucose co-transporter 2 inhibitors and impact on kidney and cardiovascular outcomes are uncertain. RESEARCH DESIGN AND METHODS: We analyzed 4395 individuals with prebaseline and postbaseline hemoglobin A1c (HbA1c) randomized to canagliflozin (n=2193) or placebo (n=2202) in The Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation trial. Effects on HbA1c were assessed using mixed models. Mediation of treatment effects by achieved glycemic control was analyzed using proportional hazards regression with and without adjustment for achieved HbA1c. End points included combined kidney or cardiovascular death, end-stage kidney disease or doubling of serum creatinine (primary trial outcome), and individual end point components. RESULTS: HbA1c lowering was modified by baseline estimated glomerular filtration rate (eGFR). For baseline eGFR 60-90, 45-59, and 30-44 mL/min/1.73 m2, overall HbA1c (canagliflozin vs placebo) decreased by -0.24%, -0.14%, and -0.08% respectively and likelihood of >0.5% decrease in HbA1c decreased with ORs of 1.47 (95% CI 1.27 to 1.67), 1.12 (0.94 to 1.33) and 0.99 (0.83 to 1.18), respectively. Adjustment for postbaseline HbA1c marginally attenuated canagliflozin effects on primary and kidney composite outcomes: unadjusted HR 0.67 (95% CI 0.57 to 0.80) and 0.66 (95% CI 0.53 to 0.81); adjusted for week 13 HbA1c, HR 0.71 (95% CI 0.060 to 0.84) and 0.68 (95% CI 0.55 to 0.83). Results adjusted for time-varying HbA1c or HbA1c as a cubic spline were similar and consistent with preserved clinical benefits across a range of excellent and poor glycemic control. CONCLUSIONS: The glycemic effects of canagliflozin are attenuated at lower eGFR but effects on kidney and cardiac end points are preserved. Non-glycemic effects may be primarily responsible for the kidney and cardioprotective benefits of canagliflozin.22.

The sodium-glucose cotransporter-2 inhibitor canagliflozin does not increase risk of non-genital skin and soft tissue infections in people with type 2 diabetes mellitus: A pooled post hoc analysis from the CANVAS Program and CREDENCE randomized double-blind trials.

AIMS: To assess whether the sodium-glucose cotransporter-2 (SGLT2) inhibitor canagliflozin affects risk of non-genital skin and soft tissue infections (SSTIs). MATERIALS AND METHODS: We performed a post hoc pooled individual participant analysis of the CANVAS Program and CREDENCE trials that randomized people with type 2 diabetes at high cardiovascular risk and/or with chronic kidney disease to either canagliflozin or placebo. Investigator-reported adverse events were assessed by two blinded authors following predetermined criteria for non-genital SSTIs. Risks of non-genital SSTIs, overall and within prespecified subgroups, and risk of non-genital fungal SSTIs, were analysed using Cox regression models. Factors associated with non-genital SSTIs were assessed using multivariable Cox regression models. RESULTS: Overall, 903 of 14 531 participants (6%) experienced non-genital SSTIs over a median follow-up of 26 months. No difference was observed in non-genital SSTI rates between canagliflozin and placebo (24.0 events/1000 person-years vs. 23.9 events/1000 person-years, respectively; hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.85-1.11; P = 0.70), with consistent results across subgroups (all P interaction > 0.05). The risk of recurrent events and non-genital fungal infection also did not differ significantly between canagliflozin and placebo (HR 1.06, 95% CI 0.94-1.19 [P = 0.32] and HR 1.18, 95% CI 0.88-1.60 [P = 0.27], respectively). Baseline factors independently associated with non-genital SSTIs were younger age, male sex, higher body mass index, higher glycated haemoglobin, lower estimated glomerular filtration rate (eGFR), established peripheral vascular disease, and history of neuropathy. CONCLUSIONS: Canagliflozin did not affect risk of non-genital SSTIs or non-genital fungal SSTIs compared with placebo. These findings suggest that any SGLT2 inhibitor-mediated change in skin microenvironment is unlikely to have meaningful clinical consequences.

Diagnostic and prognostic biomarkers for tubulointerstitial fibrosis.

Renal fibrosis is the final common pathophysiological pathway in chronic kidney disease (CKD) regardless of the underlying cause of kidney injury. Tubulointerstitial fibrosis (TIF) is considered to be the key pathological predictor of CKD progression. Currently, the gold-standard tool to identify TIF is kidney biopsy, an invasive method that carries risks. Non-invasive diagnostics rely on an estimation of glomerular filtration rate and albuminuria to assess kidney function, but these fail to diagnose early CKD accurately or to predict progressive decline in kidney function. In this review, we summarize the current and emerging molecular biomarkers that have been studied in various clinical settings and in animal models of kidney disease and that are correlated with the degree of TIF. We examine the potential of these biomarkers to diagnose TIF non-invasively and to predict disease progression. We also examine the potential of new technologies and non-invasive diagnostic approaches in assessing TIF. Limitations of current and potential biomarkers are discussed and knowledge gaps identified.

The Role of Expert Opinion in Projecting Long-Term Survival Outcomes Beyond the Horizon of a Clinical Trial.

INTRODUCTION: Clinical trials often have short follow-ups, and long-term outcomes such as survival must be extrapolated. Current extrapolation methods often produce a wide range of survival values. To minimize uncertainty in projections, we developed a novel method that incorporates formally elicited expert opinion in a Bayesian analysis and used it to extrapolate survival in the placebo arm of DAPA-CKD, a phase 3 trial of dapagliflozin in patients with chronic kidney disease (NCT03036150). METHODS: A summary of mortality data from 13 studies that included DAPA-CKD-like populations and training on elicitation were provided to six experts. An elicitation survey was used to gather the experts' 10- and 20-year survival estimates for patients in the placebo arm of DAPA-CKD. These estimates were combined with DAPA-CKD mortality and general population mortality (GPM) data in a Bayesian analysis to extrapolate long-term survival using seven parametric distributions. Results were compared with those from standard frequentist approaches (with and without GPM data) that do not incorporate expert opinion. RESULTS: The group expert-elicited estimate for 20-year survival was 31% (lower estimate, 10%; upper estimate, 40%). In the Bayesian analysis, the 20-year extrapolated survival across the seven distributions was 14.9-39.1%, a range that was 2.4- and 1.6-fold smaller than those produced by the frequentist methods (0.0-56.9% without and 0.0-39.2% with GPM data). CONCLUSIONS: Using expert opinion in a Bayesian analysis provided a robust method for extrapolating long-term survival in the placebo arm of DAPA-CKD. The method could be applied to other populations with limited survival data.

Health Care Resource Utilization and Related Costs of Patients With CKD From the United States: A Report From the DISCOVER CKD Retrospective Cohort.

Introduction: It is well established that chronic kidney disease (CKD) results in a significant burden on patients' health and health care providers. However, detailed estimates of the health care resource utilization (HCRU) of CKD are limited, particularly those which consider severity, comorbidities, and payer type. This study aimed to bridge this evidence gap by reporting contemporary HCRU and costs in patients with CKD across the US health care providers. Methods: Cost and HCRU estimates of CKD and reduced kidney function without CKD (estimated glomerular filtration rate [eGFR]: 60-75 and urine albumin-to-creatinine ratio [UACR]: <30) were derived for US patients included in the DISCOVER CKD cohort study, using linked inpatient and outpatient data from the limited claims-EMR data set (LCED) and TriNetX database. Patients with a history of transplant or undergoing dialysis were not included. HCRU and costs were stratified by CKD severity using UACR and eGFR. Results: Overall health care costs ranged from $26,889 (A1) to $42,139 (A3), and from $28,627 (G2) to $42,902 (G5) per patient per year (PPPY), demonstrating a considerable early disease burden which continued to increase with declining kidney function. The PPPY costs of later stage CKD were particularly notable for patients with concomitant heart failure ($50,191 [A3]) and those covered by commercial payers ($55,735 [A3]). Conclusions: Health care costs and resource use associated with CKD and reduced kidney function pose a substantial burden across health care systems and payers, increasing in line with CKD progression. Early CKD screening, particularly of UACR, paired with proactive disease management may provide both an improvement to patient outcomes and a significant HCRU and cost saving to health care providers.