Effect of the angiotensin-converting-enzyme inhibitor benazepril on the progression of chronic renal insufficiency. The Angiotensin-Converting-Enzyme Inhibition in Progressive Renal Insufficiency Study Group

The removal of race from kidney function estimation: Key points for primary providers

Recent recognitions of longstanding societal effects of structural and overt acts of racism have led to calls for the elimination of race, a social construct, from medical algorithms. This accelerated a growing concern with the use of race in kidney function estimating equations. A task force sponsored by the two leading nephrology societies in the United States has reassessed the inclusion of race in glomerular filtration rate (GFR) estimation and recently put forth recommendations. New race-free equations have been developed and guides for widespread implementation have been provided. We herein review the journey of kidney function estimating equations, race in GFR estimating equations, new race-free equations and the path forward in caring for chronic kidney disease. We urge upon all primary care providers to employ concerted focus on early detection and identification of kidney dysfunction as well as risk factors including social determinants of health to prevent progression.

Tight Blood Pressure Control in Chronic Kidney Disease

Hypertension affects over a billion people worldwide and is the leading cause of cardiovascular disease and premature death worldwide, as well as one of the key determinants of chronic kidney disease worldwide. People with chronic kidney disease and hypertension are at very high risk of renal outcomes, including progression to end-stage renal disease, and, even more importantly, cardiovascular outcomes. Hence, blood pressure control is crucial in reducing the human and socio-economic burden of renal and cardiovascular outcomes in those patients. However, current guidelines from hypertension and renal societies have issued different and sometimes conflicting recommendations, which risk confusing clinicians and potentially contributing to a less effective prevention of renal and cardiovascular outcomes. In this review, we critically appraise existing evidence and key international guidelines, and we finally formulate our own opinion that clinicians should aim for a blood pressure target lower than 130/80 in all patients with chronic kidney disease and hypertension, unless they are frail or with multiple comorbidities. We also advocate for an even more ambitious systolic blood pressure target lower than 120 mmHg in younger patients with a lower burden of comorbidities, to minimise their risk of renal and cardiovascular events during their lifetime.

Comparison of the Surgical Resection and Infarct 5/6 Nephrectomy Rat Models of Chronic Kidney Disease

The 5/6 nephrectomy rat remnant kidney model is commonly employed to study chronic kidney disease (CKD). This model requires removal of one whole kidney and two-thirds of the other. The two most common ways of producing the remnant kidney are surgical resection of poles, known as the polectomy (Pol) model, or ligation of upper and lower renal arterial branches, resulting in pole infarction (Inf). These models have much in common, but also major phenotypic differences, and thus respectively model unique aspects of human CKD. The purpose of this review is to summarize phenotypic similarities and differences between these two models and their relation to human CKD, while emphasizing their vascular phenotype. In this article we review studies that have evaluated arterial blood pressure, the renin-angiotensin-aldosterone-system (RAAS), autoregulation, nitric oxide, single nephron physiology, angiogenic and anti-angiogenic factors, and capillary rarefaction in these two models. Phenotypic similarities: both models spontaneously develop hallmarks of human CKD including uremia, fibrosis, capillary rarefaction, and progressive renal function decline. They both undergo whole-organ hypertrophy, hyperfiltration of functional nephrons, reduced renal expression of angiogenic factor VEGF, increased renal expression of the anti-angiogenic thrombospondin-1, impaired renal autoregulation, and abnormal vascular nitric oxide physiology. Key phenotypic differences: the Inf model develops rapid-onset, moderate-to-severe systemic hypertension, and the Pol model early normotension followed by mild-to-moderate hypertension. The Inf rat has a markedly more active renin-angiotensin-aldosterone-system. Comparison of these two models facilitates understanding of how they can be utilized for studying CKD pathophysiology (e.g., RAAS dependent or independent pathology).

Cardiometabolic and Kidney Protection in Kidney Transplant Recipients With Diabetes: Mechanisms, Clinical Applications, and Summary of Clinical Trials

Kidney transplantation is the therapy of choice for patients with end-stage renal disease. Preexisting diabetes is highly prevalent in kidney transplant recipients (KTR), and the development of posttransplant diabetes is common because of a number of transplant-specific risk factors such as the use of diabetogenic immunosuppressive medications and posttransplant weight gain. The presence of pretransplant and posttransplant diabetes in KTR significantly and variably affect the risk of graft failure, cardiovascular disease (CVD), and death. Among the many available therapies for diabetes, there are little data to determine the glucose-lowering agent(s) of choice in KTR. Furthermore, despite the high burden of graft loss and CVD among KTR with diabetes, evidence for strategies offering cardiovascular and kidney protection is lacking. Recent accumulating evidence convincingly shows glucose-independent cardiorenal protective effects in non-KTR with glucose-lowering agents, such as sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists. Therefore, our aim was to review cardiorenal protective strategies, including the evidence, mechanisms, and rationale for the use of these glucose-lowering agents in KTR with diabetes.

Genotype-Phenotype correlations of SCARB2 associated clinical presentation: a case report and in-depth literature review

BACKGROUND

Biallelic pathogenic variants in the SCARB2 gene have been associated with action myoclonus-renal failure (AMRF) syndrome. Even though SCARB2 associated phenotype has been reported to include typical neurological characteristics, depending on the localization and the feature of the pathogenic variants, clinical course and the presentations have been shown to differ.

CASE PRESENTATION

Whole exome sequencing (WES) analysis revealed a homozygous truncating variant (p.N45MfsX88) in SCARB2 gene in the index case, and subsequent sanger sequencing analysis validated the variant in all affected family members from a Turkish family with the clinical characteristics associated with AMRF and related disorders. Intrafamilial clinical heterogeneity with common features including dysarthria, tremor and proteinuria, and distinct features such as peripheral neuropathy (PNP), myoclonus and seizures between the affected cases, was observed in the family. In-depth literature review enabled the detailed investigation of the reported variants associated with AMRF and suggested that while the type of the variant did not have a major impact on the course of the clinical characteristics, only the C terminal localization of the pathogenic variant significantly affected the clinical presentation, particularly the age at onset (AO) of the disease.

CONCLUSIONS

In this study we showed that biallelic SCARB2 pathogenic variants might cause a spectrum of common and distinct features associated with AMRF. Of those features while the common features include myoclonus (100%), ataxia (96%), tonic clonic seizures (82%), dysarthria (68%), tremor (65%), and renal impairment (62%), the uncommon features involve PNP (17%), hearing loss (6.8%), and cognitive impairment (13.7%). AO has been found to be significantly higher in the carriers of the p.G462DfsX34 pathogenic variant. SCARB2 pathogenic variants have not been only implicated in AMRF but also in the pathogenesis of Parkinson's disease (PD) and Gaucher disease (GD), suggesting the importance of genetic and functional studies in the clinical and the diagnostic settings. Given the proven role of SCARB2 gene in the pathogenesis of AMRF, PD and GD with a wide spectrum of clinical symptoms, investigation of the possible modifiers, such as progranulin and HSP7, has a great importance.

A Resampling Method to Improve the Prognostic Model of End-Stage Kidney Disease: A Better Strategy for Imbalanced Data

Background

Prognostic models can help to identify patients at risk for end-stage kidney disease (ESKD) at an earlier stage to provide preventive medical interventions. Previous studies mostly applied the Cox proportional hazards model. The aim of this study is to present a resampling method, which can deal with imbalanced data structure for the prognostic model and help to improve predictive performance.

Methods

The electronic health records of patients with chronic kidney disease (CKD) older than 50 years during 2005–2015 collected from primary care in Belgium were used (n = 11,645). Both the Cox proportional hazards model and the logistic regression analysis were applied as reference model. Then, the resampling method, the Synthetic Minority Over-Sampling Technique-Edited Nearest Neighbor (SMOTE-ENN), was applied as a preprocessing procedure followed by the logistic regression analysis. The performance was evaluated by accuracy, the area under the curve (AUC), confusion matrix, and F₃ score.

Results

The C statistics for the Cox proportional hazards model was 0.807, while the AUC for the logistic regression analysis was 0.700, both on a comparable level to previous studies. With the model trained on the resampled set, 86.3% of patients with ESKD were correctly identified, although it was at the cost of the high misclassification rate of negative cases. The F₃ score was 0.245, much higher than 0.043 for the logistic regression analysis and 0.022 for the Cox proportional hazards model.

Conclusion

This study pointed out the imbalanced data structure and its effects on prediction accuracy, which were not thoroughly discussed in previous studies. We were able to identify patients with high risk for ESKD better from a clinical perspective by using the resampling method. But, it has the limitation of the high misclassification of negative cases. The technique can be widely used in other clinical topics when imbalanced data structure should be considered.

RAAS Inhibitor Prescription and Hyperkalemia Event in Patients With Chronic Kidney Disease: A Single-Center Retrospective Study

Hyperkalemia is common in patients treated with renin-angiotensin-aldosterone system inhibitors (RAASis), and it represents the main cause of the large gap reported between guideline recommendations and real-world practice in chronic kidney disease (CKD). We conducted a CKD-population-based restrospective study to determine the prevalence of patients with CKD treated with RAASis, incidence of hyperkalemia in patients with CKD treated with RAASis, and proportion of patients with RAASi medication change after experiencing incident hyperkalemia. Among 809 patients with CKD analyzed, 556 (68.7%) were treated with RAASis, and RAASi prescription was greater in stages 2-4 of CKD. Hyperkalemia occurred in 9.2% of RAASi-treated patients, and the adjusted rate of hyperkalemia among patients with stage 4-5 CKD was 3-fold higher compared with patients with eGFR > 60 ml/min/1.73 m2. RAASi treatment was discontinued in 55.3% of the patients after hyperkalemia event (74.2% discontinued therapy, 3.2% received a reduced dose, and 22.6% reduced the number of RAASi drugs). This study shows that the incidence of hyperkalemia is frequently observed in patients with CKD patients with RAASis, and that rates increase with deteriorating levels of kidney function from stages 1 to 3. RAASi medication change following an episode of hyperkalemia occurred in almost half of the patients after experiencing hyperkalemia.

Acute Treatment Effects on GFR in Randomized Clinical Trials of Kidney Disease Progression

BACKGROUND

Acute changes in GFR can occur after initiation of interventions targeting progression of CKD. These acute changes complicate the interpretation of long-term treatment effects.

METHODS

To assess the magnitude and consistency of acute effects in randomized clinical trials and explore factors that might affect them, we performed a meta-analysis of 53 randomized clinical trials for CKD progression, enrolling 56,413 participants with at least one estimated GFR measurement by 6 months after randomization. We defined acute treatment effects as the mean difference in GFR slope from baseline to 3 months between randomized groups. We performed univariable and multivariable metaregression to assess the effect of intervention type, disease state, baseline GFR, and albuminuria on the magnitude of acute effects.

RESULTS

The mean acute effect across all studies was -0.21 ml/min per 1.73 m2 (95% confidence interval, -0.63 to 0.22) over 3 months, with substantial heterogeneity across interventions (95% coverage interval across studies, -2.50 to +2.08 ml/min per 1.73 m2). We observed negative average acute effects in renin angiotensin system blockade, BP lowering, and sodium-glucose cotransporter 2 inhibitor trials, and positive acute effects in trials of immunosuppressive agents. Larger negative acute effects were observed in trials with a higher mean baseline GFR.

CONCLUSION

The magnitude and consistency of acute GFR effects vary across different interventions, and are larger at higher baseline GFR. Understanding the nature and magnitude of acute effects can help inform the optimal design of randomized clinical trials evaluating disease progression in CKD.

Current options for slowing the progression of chronic kidney disease

From a certain stage, chronic kidney disease progresses to terminal kidney failure that requires renal replacement therapy with dialysis or transplantation. The progression can be significantly slowed by blocking the renin angiotensin aldosterone system (RAAS) with angiotensin converting enzyme (ACE) inhibitors or angiotensin II type 1 receptor blockers (ARB). Another new option to enhance the effect of blocking the RAAS system is the use of sodium glucose cotransporter 2 (SGLT2) inhibitors, or gliflozins. Dapagliflozin is currently available and reimbursed for patients with both diabetic and non-diabetic kidney disease. In the near future, treatment with the mineralocorticoid receptor inhibitor finerenone should be made available that significantly potentiates the effect of ACE or ARB inhibitors. Recent data show that it is possible to influence the progression of renal insufficiency with exercise.

Chronic Kidney Disease and SGLT2 Inhibitors: A Review of the Evolving Treatment Landscape

There is currently an unmet need for effective treatment of chronic kidney disease (CKD) that slows disease progression, prevents development of end-stage kidney disease and cardiovascular disease, and prolongs survival of patients with CKD. In the last 20 years, the only agents to show a reduction in the risk of CKD progression in patients with and without type 2 diabetes (T2D) were angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, but neither drug class has provided a decreased risk of all-cause mortality in patients with CKD and evidence for their use in patients with CKD without T2D is relatively limited. This review discusses the mechanisms underlying the progression of CKD, its associated risk factors, and summarizes the potential therapeutic approaches for managing CKD. There is increasing evidence to support the role of sodium-glucose cotransporter 2 (SGLT2) inhibitor therapy in patients with CKD, including data from the designated kidney outcome trials in patients with T2D (CREDENCE) and in patients with or without T2D (DAPA-CKD). These studies showed a significant reduction in the risk of CKD progression with canagliflozin (in patients with T2D) or dapagliflozin (in patients with or without T2D), respectively, with DAPA-CKD being the first trial to show a reduced risk of all-cause mortality. On the basis of these data, individualized treatment with SGLT2 inhibitors represents a promising therapeutic option for patients with diabetic and nondiabetic CKD to slow disease progression.

Multiple comorbid conditions and healthcare resource utilization among adult patients with hyperkalemia: A retrospective observational cohort study using association rule mining

Objectives

To estimate the prevalence of specific comorbid conditions (CCs) and multiple comorbid conditions (MCCs) among adult patients with hyperkalemia and examine the associations between MCCs and healthcare resource utilization (HRU) and costs.

Methods

This retrospective observational cohort study was conducted using a large administrative claims database. We identified patients with hyperkalemia (ICD-10-CM: E87.5; or serum potassium >5.0 mEq/L; or NDC codes for either patiromer or sodium polystyrene sulfonate) during the study period (1/1/2016–6/30/2019). The earliest service/claim date with evidence of hyperkalemia was identified as index date. Qualified patients had ≥12 months of enrolment before and after index date, ≥18 years of age. Comorbid conditions were assessed using all data within 12 months prior to the index date. Healthcare resource utilization and costs were estimated using all data within 12 months after the index date. Association rule mining was applied to identify MCCs. Generalized linear models were used to examine the associations between MCCs and HRU and costs.

Results

Of 22,154 patients with hyperkalemia, 94% had ≥3 CCs. The most common individual CCs were chronic kidney disease (CKD, 85%), hypertension (HTN, 83%), hyperlipidemia (HLD, 81%), and diabetes mellitus (DM, 47%). The most common dyad combination of CCs was CKD+HTN (71%). The most common triad combination was CKD+HTN+HLD (62%). The most common quartet combination was CKD+HTN+HLD+DM (36%). The increased number of CCs were significantly associated with increased ED visits, length of hospital stays, and total healthcare costs (all p-value < 0.0001).

Conclusions

MCCs are very prevalent among patients with hyperkalemia and are strongly associated with HRU and costs.

Treatments for Chronic Kidney Disease: A Systematic Literature Review of Randomized Controlled Trials

Delaying disease progression and reducing the risk of mortality are key goals in the treatment of chronic kidney disease (CKD). New drug classes to augment renin-angiotensin-aldosterone system (RAAS) inhibitors as the standard of care have scarcely met their primary endpoints until recently. This systematic literature review explored treatments evaluated in patients with CKD since 1990 to understand what contemporary data add to the treatment landscape. Eighty-nine clinical trials were identified that had enrolled patients with estimated glomerular filtration rate 13.9-102.8 mL/min/1.73 m2 and urinary albumin-to-creatinine ratio (UACR) 29.9-2911.0 mg/g, with (75.5%) and without (20.6%) type 2 diabetes (T2D). Clinically objective outcomes of kidney failure and all-cause mortality (ACM) were reported in 32 and 64 trials, respectively. Significant reductions (P < 0.05) in the risk of kidney failure were observed in seven trials: five small trials published before 2008 had evaluated the RAAS inhibitors losartan, benazepril, or ramipril in patients with (n = 751) or without (n = 84-436) T2D; two larger trials (n = 2152-2202) published onwards of 2019 had evaluated the sodium-glucose co-transporter 2 (SGLT2) inhibitors canagliflozin (in patients with T2D and UACR > 300-5000 mg/g) and dapagliflozin (in patients with or without T2D and UACR 200-5000 mg/g) added to a background of RAAS inhibition. Significant reductions in ACM were observed with dapagliflozin in the DAPA-CKD trial. Contemporary data therefore suggest that augmenting RAAS inhibitors with new drug classes has the potential to improve clinical outcomes in a broad range of patients with CKD.

Hypertension Management in Patients with Chronic Kidney Disease in the Post-SPRINT Era

The management of high blood pressure (BP) is crucial for improving outcomes in patients with chronic kidney disease (CKD). The updated Kidney Disease: Improving Global Outcomes 2021 BP guideline proposes treating adults with CKD to a target systolic BP (SBP) of <120 mmHg based on the standardized office BP measurement. This suggestion is largely based on the finding of SPRINT (Systolic Blood Pressure Intervention Trial) that targeting an SBP of <120 mmHg versus <140 mmHg is beneficial for cardiovascular and mortality outcomes, regardless of the patient's kidney disease status. However, extended follow-up studies of CKD trials showed that intensive versus usual BP control was associated with a lower risk of kidney failure in patients with, but not in those without, proteinuria. Similarly, a recent population-based study in Korea demonstrated that the optimal on-treatment BP for composite cardiorenal and mortality outcomes was left-shifted in adults with CKD, particularly in those with albuminuria, relative to that in patients without CKD. Moreover, in meta-analyses of randomized trials, more intensive versus standard BP control was associated with a lower risk of all-cause mortality in patients with CKD and albuminuria but not in those without CKD. Meanwhile, a 2020 Cochrane review reported that lower BP targets (≤135/85 mmHg), compared with standard targets (≤140/90 mmHg), resulted in a small reduction in cardiovascular events, an increase in other serious adverse events, and no reduction in total serious adverse events. Lowering SBP to <120 mmHg can potentially increase the risk of treatment-related adverse events beyond the cardioprotective benefits, and standardized BP measurement increases the burden on patients and resources. Thus, targeting a BP of <130/80 mmHg with appropriate office BP measurement can be an option in patients with CKD. The presence of albuminuria would need to be additionally considered to determine individualized BP targets.

The therapeutic potential of apelin in kidney disease

Chronic kidney disease (CKD) is a leading cause of global morbidity and mortality and is independently associated with cardiovascular disease. The mainstay of treatment for CKD is blockade of the renin-angiotensin-aldosterone system (RAAS), which reduces blood pressure and proteinuria and slows kidney function decline. Despite this treatment, many patients progress to kidney failure, which requires dialysis or kidney transplantation, and/or die as a result of cardiovascular disease. The apelin system is an endogenous physiological regulator that is emerging as a potential therapeutic target for many diseases. This system comprises the apelin receptor and its two families of endogenous ligands, apelin and elabela/toddler. Preclinical and clinical studies show that apelin receptor ligands are endothelium-dependent vasodilators and potent inotropes, and the apelin system has a reciprocal relationship with the RAAS. In preclinical studies, apelin regulates glomerular haemodynamics and acts on the tubule to promote aquaresis. In addition, apelin is protective in several kidney injury models. Although the apelin system has not yet been studied in patients with CKD, the available data suggest that apelin is a promising potential therapeutic target for kidney disease.

Effectiveness and Tolerance of Renin-Angiotensin System Inhibitors With Aging in Chronic Kidney Disease

OBJECTIVES

Renin-angiotensin system inhibitors (RASi) are recommended for slowing chronic kidney disease (CKD) progression to kidney failure. Their effectiveness and tolerance as patients age remain uncertain because older patients have often been excluded from clinical trials.

DESIGN

CKD-REIN cohort study.

SETTING AND PARTICIPANTS

We studied 2762 patients with CKD stages 3 and 4 and a clinical indication for RASi enrolled between 2013 and 2016 in 40 nephrology clinics nationally representative in France.

METHODS

The primary outcome was the occurrence of kidney failure or death. The secondary outcomes were the occurrence of cardiovascular events and hospitalizations with acute kidney injury (AKI) or hyperkalemia. A propensity score analysis was performed. We used Cox models to estimate hazard ratios (HRs) for each outcome associated with RASi prescription and tested interactions with age.

RESULTS

Patients' mean age was 67 years, including 841 (30%) aged 75 years and older; 2178 (79%) were prescribed RASi's. During a median follow-up of 4.6 years, 33% of patients reached kidney failure or died. RASi prescription was associated with a lower risk of kidney failure or death (HR 0.79, 95% CI 0.66, 0.95), an association not modified by age (P for interaction = .72). It was not significantly associated with cardiovascular events. During the first 3 years of follow-up, 14% of patients were hospitalized with AKI or hyperkalemia, but risk was not higher among those prescribed RASi's (HR 0.75, 95% CI 0.55-1.02) and age did not modify its effect (P for interaction = .28).

CONCLUSIONS AND IMPLICATIONS

This study shows that aging does not appear to modify either RASi's beneficial effects on major CKD outcomes or their potential adverse effects.

Renin Angiotensin Aldosterone System Inhibitors in Chronic Kidney Disease: A Difficult Equation

Chronic kidney disease (CKD) is a global health problem and is strongly associated with hypertension (HTN) and impaired quality of life. Managing HTN with agents that block the renin angiotensin aldosterone system (RAAS) remains the gold standard, however there is a misleading impression that patients with impaired renal function or those receiving hemodialysis should not be treated with RAAS inhibitors. To date, only a few data in this field are available, given that this population subset is systematically excluded from many major clinical trials. The purpose of this review was to solve the difficult equation regarding the optimal use of RAAS blockade in patients with CKD.

Association between early post-transplant hypertension or related antihypertensive use and prognosis of kidney transplant recipients: a nationwide observational study

BACKGROUND

Additional research is warranted for the clinical significance of post-transplant hypertension and related antihypertensive medication use in kidney transplant (KT) recipients.

METHODS

This observational study included nationwide KT recipients who maintained a functioning graft for at least 1 year after KT in South Korea, observed between 2008 and 2017. The use of antihypertensive medications lasting between 6 months and 1 year was the main exposure, and those who had inconsistent/transient use of antihypertensive drugs were excluded. The prognostic outcome included death-censored graft failure (DCGF), death-with functioning graft (DWFG), and major adverse cerebrocardiovascular events (MACCEs).

RESULTS

We included 8,014 patients without post-transplant hypertension and 6,114 recipients who received treatment for hypertension in the post-transplant period. Those with post-transplant hypertension had a significantly higher risk of DCGF than those without [adjusted hazard ratio (HR) 1.27 (1.09-1.48)]. Post-transplant hypertension patients who required multiple drugs showed a significantly higher risk of DWFG [HR 1.57 (1.17-2.10)] and MACCE [HR 1.35 (1.01-1.81)] than the controls. Among the single-agent users, those who received beta-blockers showed a significantly higher risk of DCGF, although the risks of DWFG or MACCE were similar between the types of antihypertensive agents. Among the multiple agent users, the prognosis was similar, regardless of the prescribed types of antihypertensive agents.

CONCLUSION

Post-transplant hypertension was associated with poor post-transplant prognosis, particularly when multiple types of medications were required for treatment. During initial prescription of antihypertensive medication, clinicians may consider that beta-blockers were associated with a higher risk of DCGF in the single-agent users.

Management of Blood Pressure in Patients With Chronic Kidney Disease Not Receiving Dialysis: Synopsis of the 2021 KDIGO Clinical Practice Guideline

DESCRIPTION

The Kidney Disease: Improving Global Outcomes (KDIGO) 2021 clinical practice guideline for the management of blood pressure (BP) in patients with chronic kidney disease (CKD) not receiving dialysis is an update of the KDIGO 2012 guideline on the same topic and reflects new evidence on the risks and benefits of BP-lowering therapy among patients with CKD. It is intended to support shared decision making by health care professionals working with patients with CKD worldwide. This article is a synopsis of the full guideline.

METHODS

The KDIGO leadership commissioned 2 co-chairs to convene an international Work Group of researchers and clinicians. After a Controversies Conference in September 2017, the Work Group defined the scope of the evidence review, which was undertaken by an evidence review team between October 2017 and April 2020. Evidence reviews were done according to the Cochrane Handbook. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach was used to guide the development of the recommendations and rate the strength and quality of the evidence. Practice points were included to provide guidance when evidence was insufficient to make a graded recommendation. The guideline was revised after public consultation between January and March 2020.

RECOMMENDATIONS

The updated guideline comprises 11 recommendations and 20 practice points. This synopsis summarizes key recommendations pertinent to the diagnosis and management of high BP in adults with CKD, excluding those receiving kidney replacement therapy. In particular, the synopsis focuses on recommendations for standardized BP measurement and a target systolic BP of less than 120 mm Hg, because these recommendations differ from some other guidelines.

Effects of Dapagliflozin in Stage 4 Chronic Kidney Disease

BACKGROUND

In the Dapagliflozin and Prevention of Adverse Outcomes in Chronic Kidney Disease (DAPA-CKD) randomized, placebo-controlled trial, the sodium-glucose cotransporter 2 inhibitor dapagliflozin significantly reduced risk of kidney failure and prolonged survival in patients with CKD with or without type 2 diabetes.

METHODS

Adults with eGFR of 25-75 ml/min per 1.73 m² and urinary albumin-to-creatinine ratio of 200-5000 mg/g had been randomized to receive dapagliflozin 10 mg/d or placebo. Here, we conducted a prespecified analysis of dapagliflozin's effects in patients with stage 4 CKD (eGFR,30 ml/min per 1.73 m²) at baseline. The primary end point was a composite of time to ≥50% sustained decline in eGFR, ESKD, or kidney or cardiovascular death. Secondary end points were a kidney composite (same as the primary end point but without cardiovascular death), a composite of cardiovascular death or heart failure hospitalization, and all-cause death.

RESULTS

A total of 293 participants with stage 4 CKD received dapagliflozin and 331 received placebo. Patients with stage 4 CKD randomized to dapagliflozin experienced a 27% (95% confidence interval [95% CI]: -2 to 47%) reduction in the primary composite endpoint, and 29% (-2 to 51%), 17% (-53 to 55%), and 32% (-21 to 61%) reductions in the kidney, cardiovascular and mortality endpoints, respectively, relative to placebo. Interaction P-values were 0.22, 0.13, 0.63, and 0.95, respectively, comparing CKD stages 4 versus 2/3. The eGFR slope declined by 2.15 and 3.38 ml/min per 1.73 m² per year in the dapagliflozin and placebo groups, respectively (P=0.005). Patients treated with dapagliflozin or placebo had similar rates of serious adverse events and adverse events of interest.

CONCLUSIONS

Among patients with stage 4 CKD and albuminuria, the effects of dapagliflozin were consistent with those observed in the DAPA-CKD trial overall, with no evidence of increased risks.

Inhibition of sodium-glucose cotransporter 2 to slow the progression of chronic kidney disease

Chronic kidney disease (CKD) is a major public health problem, increasing the risk of cardiovascular events and death and potentially leading to kidney failure. Novel drugs that slow the progression of this non-communicable disease are therefore urgently needed. Initially developed as glucose-lowering drugs, inhibitors of the sodium-glucose cotransporter 2 (SGLT2) drastically reduce the overall mortality and cardiovascular events and slow the progression of CKD. Kidney protection conferred by SGLT2 inhibitors is independent from the presence of diabetes, observed on top of renin-angiotensin system inhibition and consistent across a wide range of categories of glomerular filtration rate and albuminuria. The mechanisms through which SGLT2 inhibitors improve kidney outcomes are likely multifactorial. Inhibition of SGLT2 in the kidney proximal tubule results in natriuresis and glucosuria, with beneficial effects on metabolic control, blood pressure and body weight. In addition, SGLT2 inhibitors also improve intraglomerular hemodynamics, podocyte integrity, cell metabolism, and erythropoiesis and reduce hypoxia, oxidative stress, sympathetic nervous activity, inflammation and fibrosis. The major impact of SGLT2 inhibitors on kidney outcomes, along with the excellent safety profile of this new class of drugs, open novel avenues for the treatment of CKD in patients with and without diabetes.

Hyperkalemia in Chronic Kidney Disease in the New Era of Kidney Protection Therapies

Despite recent therapeutic advances, chronic kidney disease (CKD) is one of the fastest growing global causes of death. This illustrates limitations of current therapeutic approaches and, potentially, unidentified knowledge gaps. For decades, renin-angiotensin-aldosterone system (RAAS) blockers have been the mainstay of therapy for CKD. However, they favor the development of hyperkalemia, which is already common in CKD patients due to the CKD-associated decrease in urinary potassium (K⁺) excretion and metabolic acidosis. Hyperkalemia may itself be life-threatening as it may trigger potentially lethal arrhythmia, and additionally may limit the prescription of RAAS blockers and lead to low-K⁺ diets associated to low dietary fiber intake. Indeed, hyperkalemia is associated with adverse kidney, cardiovascular, and survival outcomes. Recently, novel kidney protective therapies, ranging from sodium/glucose cotransporter 2 (SGLT2) inhibitors to new mineralocorticoid receptor antagonists have shown efficacy in clinical trials. Herein, we review K⁺ pathophysiology and the clinical impact and management of hyperkalemia considering these developments and the availability of the novel K⁺ binders patiromer and sodium zirconium cyclosilicate, recent results from clinical trials targeting metabolic acidosis (sodium bicarbonate, veverimer), and an increasing understanding of the role of the gut microbiota in health and disease.

Primary prevention of cardiovascular disease events with renin-angiotensin system blockade in autosomal dominant polycystic kidney disease dialysis patients: A nationwide cohort study

Although renin-angiotensin system (RAS) blockade has been shown to reduce cardiovascular disease (CVD) in the general population and high-risk subjects, their protective effect in autosomal dominant polycystic kidney disease (ADPKD) patients under dialysis was still unknown. By using the database from 1995 to 2008 Taiwan National Health Insurance Research Database (Registry for Catastrophic Illnesses), we included 387 ADPKD patients who received dialysis therapy, aged ≥ 18 year-old, and with no evidence of CVD events in 1997 and 1998. We utilized Cox proportional hazards regression analysis and propensity score matching to evaluate adjusted hazard ratios for all-cause mortality and CVD events in users (n=231) and nonusers (n = 156) of an angiotensin-converting enzymes inhibitor (ACEI) / angiotensin II receptor blocker (ARB) during the 12 years of follow-up. All study subjects were followed up for more than 3 months. There was no significant difference between the ACEI/ARB treatment group and the control group in incident CVD events except ischemic stroke and transient ischemic accident (TIA). The results remain similar between groups before and after propensity score matching. Moreover, there was no significant difference in outcomes between ACEI/ARB treatment over 50% of follow-up period and without ACEI/ARB treatment after propensity score matching. This nationwide cohort study failed to prove the protective effects of long-term ACEI or ARB on incident CVD events among APKD dialysis patients. Further larger scale, multicenter and randomized control trials are warranted to show the causal association.

When should we start and stop ACEi/ARB in paediatric chronic kidney disease?

Renin-angiotensin-aldosterone inhibitors (RAASi) are the mainstay therapy in both adult and paediatric chronic kidney disease (CKD). RAASi slow down the progression of kidney failure by optimization of blood pressure and reduction of proteinuria. Despite recommendations from published guidelines in adults, the evidence related to the use of RAASi is surprisingly scarce in children. Moreover, their role in advanced CKD remains controversial. Without much guidance from the literature, paediatric nephrologists may discontinue RAASi in patients with advanced CKD due to apparent worsening of kidney function, hyperkalaemia and hypotension. Current data suggest that this strategy may in fact lead to a more rapid decline in kidney function. The optimal approach in this clinical scenario is still not well defined and there are varying practices worldwide. We will in this review describe the existing evidence on the use of RAASi in CKD with particular focus on paediatric data. We will also address the use of RAASi in advanced CKD and discuss the potential benefits and harms. At the end, we will suggest a practical approach for the use of RAASi in children with CKD based on current state of knowledge.

Medicaid Expansion and Incidence of Kidney Failure among Nonelderly Adults

BACKGROUND

Low-income individuals without health insurance have limited access to health care. Medicaid expansions may reduce kidney failure incidence by improving access to chronic disease care.

METHODS

Using a difference-in-differences analysis, we examined the association between Medicaid expansion status under the Affordable Care Act (ACA) and the kidney failure incidence rate among all nonelderly adults, aged 19-64 years, in the United States, from 2012 through 2018. We compared changes in kidney failure incidence in states that implemented Medicaid expansions with concurrent changes in nonexpansion states during pre-expansion, early postexpansion (years 2 and 3 postexpansion), and later postexpansion (years 4 and 5 postexpansion).

RESULTS

The unadjusted kidney failure incidence rate increased in the early years of the study period in both expansion and nonexpansion states before stabilizing. After adjustment for population sociodemographic characteristics, Medicaid expansion status was associated with 2.20 fewer incident cases of kidney failure per million adults per quarter in the early postexpansion period (95% CI, -3.89 to -0.51) compared with nonexpansion status, a 3.07% relative reduction (95% CI, -5.43% to -0.72%). In the later postexpansion period, Medicaid expansion status was not associated with a statistically significant change in kidney failure incidence (-0.56 cases per million per quarter; 95% CI, -2.71 to 1.58) compared with nonexpansion status and the pre-expansion time period.

CONCLUSIONS

The ACA Medicaid expansion was associated with an initial reduction in kidney failure incidence among the entire, nonelderly, adult population in the United States; but the changes did not persist in the later postexpansion period. Further study is needed to determine the long-term association between Medicaid expansion and changes in kidney failure incidence.

Antihypertensive Potential of Plant Foods: Research Progress and Prospect of Plant-Derived Angiotensin-Converting Enzyme Inhibition Compounds

Global health concerns are clearly evidenced by cardiovascular disease, kidney damage, and heart attacks. Antihypertensive synthetic drugs, including angiotensin-converting enzyme (ACE) inhibitors, effectively control hypertension but with unpleasant side effects. In recent decades, studies on the role of food-derived compounds have provided a positive contribution to ACE regulation. Here, the research progress of plant food-derived phenolic compounds as ACE inhibitors is reviewed. A survey of bioactive compounds of plant food is presented to broaden the source scope of natural ACE inhibitors. A consecutive understanding of plant-derived ACE inhibitors classification, inhibition mechanism, structure-activity relationship, and bioavailability are scientifically organized. The emerging evidence highlights areas that need further research, including those related to molecular structure, bioaccessibility, and interactions with gut microflora. Future research on such topics may encourage basic research and clinic application to exploit these plant food constituents as novel ACE inhibitors.

Mineralcorticoid receptor blockers in chronic kidney disease

There are many experimental data supporting the involvement of aldosterone and mineralcorticoid receptor (MR) activation in the genesis and progression of chronic kidney disease (CKD) and cardiovascular damage. Many studies have shown that in diabetic and non-diabetic CKD, blocking the renin-angiotensin-aldosterone (RAAS) system with conversion enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARBs) decreases proteinuria, progression of CKD and mortality, but there is still a significant residual risk of developing these events. In subjects treated with ACEi or ARBs there may be an aldosterone breakthrough whose prevalence in subjects with CKD can reach 50%. Several studies have shown that in CKD, the aldosterone antagonists (spironolactone, eplerenone) added to ACEi or ARBs, reduce proteinuria, but increase the risk of hyperkalemia. Other studies in subjects treated with dialysis suggest a possible beneficial effect of antialdosteronic drugs on CV events and mortality. Newer potassium binders drugs can prevent/decrease hyperkalemia induced by RAAS blockade, and may reduce the high discontinuation rates or dose reduction of RAAS-blockers. The nonsteroidal MR blockers, with more potency and selectivity than the classic ones, reduce proteinuria and have a lower risk of hyperkalemia. Several clinical trials, currently underway, will determine the effect of classic MR blockers on CV events and mortality in subjects with stage 3b CKD and in dialysis patients, and whether in patients with type 2 diabetes mellitus and CKD, optimally treated and with high risk of CV and kidney events, the addition of finerenone to their treatment produces cardiorenal benefits. Large randomized trials have shown that sodium glucose type 2 cotransporter inhibitors (SGLT2i) reduce mortality and the development and progression of diabetic and nondiabetic CKD. There are pathophysiological arguments, which raise the possibility that the triple combination ACEi or ARBs, SGLT2i and aldosterone antagonist provide additional renal and cardiovascular protection.

The inflammatory state is a risk factor for cardiovascular disease and graft fibrosis in kidney transplantation

Several factors, such as donor brain death, ischemia-reperfusion injury, rejection, infection, and chronic allograft dysfunction, may induce an inflammatory state in kidney transplantation. Furthermore, inflammatory cells, cytokines, growth factors, complement and coagulation cascade create an unbalanced interaction with innate and adaptive immunity, which are both heavily involved in atherogenesis. The crosstalk between inflammation and thrombosis may lead to a prothrombotic state and impaired fibrinolysis in kidney transplant recipients increasing the risk of cardiovascular disease. Inflammation is also associated with elevated levels of fibroblast growth factor 23 and low levels of Klotho, which contribute to major adverse cardiovascular events. Hyperuricemia, glucose intolerance, arterial hypertension, dyslipidemia, and physical inactivity may create a condition called metaflammation that concurs in atherogenesis. Another major consequence of the inflammatory state is the development of chronic hypoxia that through the mediation of interleukins 1 and 6, angiotensin II, and transforming growth factor beta can result in excessive accumulation of extracellular matrix, which can disrupt and replace functional parenchyma, leading to interstitial fibrosis and chronic allograft dysfunction. Lifestyle and regular physical activity may reduce inflammation. Several drugs have been proposed to control the graft inflammatory state, including low-dose aspirin, statins, renin-angiotensin inhibitors, xanthine-oxidase inhibitors, vitamin D supplements, and interleukin-6 blockade. However, no prospective controlled trial with these measures has been conducted in kidney transplantation.

Angiotensin-(1-7)-A Potential Remedy for AKI: Insights Derived from the COVID-19 Pandemic

Membrane-bound angiotensin converting enzyme (ACE) 2 serves as a receptor for the Sars-CoV-2 spike protein, permitting viral attachment to target host cells. The COVID-19 pandemic brought into light ACE2, its principal product angiotensin (Ang) 1-7, and the G protein-coupled receptor for the heptapeptide (MasR), which together form a still under-recognized arm of the renin–angiotensin system (RAS). This axis counteracts vasoconstriction, inflammation and fibrosis, generated by the more familiar deleterious arm of RAS, including ACE, Ang II and the ang II type 1 receptor (AT1R). The COVID-19 disease is characterized by the depletion of ACE2 and Ang-(1-7), conceivably playing a central role in the devastating cytokine storm that characterizes this disorder. ACE2 repletion and the administration of Ang-(1-7) constitute the therapeutic options currently tested in the management of severe COVID-19 disease cases. Based on their beneficial effects, both ACE2 and Ang-(1-7) have also been suggested to slow the progression of experimental diabetic and hypertensive chronic kidney disease (CKD). Herein, we report a further step undertaken recently, utilizing this type of intervention in the management of evolving acute kidney injury (AKI), with the expectation of renal vasodilation and the attenuation of oxidative stress, inflammation, renal parenchymal damage and subsequent fibrosis. Most outcomes indicate that triggering the ACE2/Ang-(1-7)/MasR axis may be renoprotective in the setup of AKI. Yet, there is contradicting evidence that under certain conditions it may accelerate renal damage in CKD and AKI. The nature of these conflicting outcomes requires further elucidation.

The Angiotensin II Receptor Blocker Losartan Sensitizes Human Liver Cancer Cells to Lenvatinib-Mediated Cytostatic and Angiostatic Effects

Molecular targeted therapy with lenvatinib is commonly offered to advanced hepatocellular carcinoma (HCC) patients, although it is often interrupted by adverse effects which require a reduction in the initial dose. Thus, an alternative lenvatinib-based therapy to compensate for dose reduction is anticipated. This study aimed to assess the effect of combination of low-dose of lenvatinib and the angiotensin-II (AT-II) receptor blocker losartan on human HCC cell growth. In vitro studies found that losartan suppressed the proliferation by inducing G1 arrest and caused apoptosis as indicated by the cleavage of caspase-3 in AT-II-stimulated HCC cell lines (Huh-7, HLE, and JHH-6). Losartan attenuated the AT-II-stimulated production of vascular endothelial growth factor-A (VEGF-A) and interleukin-8 and suppressed lenvatinib-mediated autocrine VEGF-A production in HCC cells. Moreover, it directly inhibited VEGF-mediated endothelial cell growth. Notably, the combination of lenvatinib and losartan augmented the cytostatic and angiostatic effects of the former at a low-dose, reaching those achieved with a conventional dose. Correspondingly, a HCC tumor xenograft assay showed that the oral administration of losartan combined with lenvatinib reduced the subcutaneous tumor burden and intratumor vascularization in BALB/c nude mice. These findings support that this regimen could be a viable option for patients intolerant to standard lenvatinib dosage.

Executive summary of the KDIGO 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease

The Kidney Disease: Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease for patients not receiving dialysis represents an update to the KDIGO 2012 guideline on this topic. Development of this guideline update followed a rigorous process of evidence review and appraisal. Guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence. The strength of recommendations is based on the "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) approach. The scope includes topics covered in the original guideline, such as optimal blood pressure targets, lifestyle interventions, antihypertensive medications, and specific management in kidney transplant recipients and children. Some aspects of general and cardiovascular health, such as lipid and smoking management, are excluded. This guideline also introduces a chapter dedicated to proper blood pressure measurement since all large randomized trials targeting blood pressure with pivotal outcomes used standardized preparation and measurement protocols adhered to by patients and clinicians. Based on previous and new evidence, in particular the Systolic Blood Pressure Intervention Trial (SPRINT) results, we propose a systolic blood pressure target of less than 120 mm Hg using standardized office reading for most people with chronic kidney disease (CKD) not receiving dialysis, the exception being children and kidney transplant recipients. The goal of this guideline is to provide clinicians and patients a useful resource with actionable recommendations supplemented with practice points. The burden of the recommendations on patients and resources, public policy implications, and limitations of the evidence are taken into consideration. Lastly, knowledge gaps and recommendations for future research are provided.

Association between antihypertensive treatment and adverse events: systematic review and meta-analysis

OBJECTIVE

To examine the association between antihypertensive treatment and specific adverse events.

DESIGN

Systematic review and meta-analysis.

ELIGIBILITY CRITERIA

Randomised controlled trials of adults receiving antihypertensives compared with placebo or no treatment, more antihypertensive drugs compared with fewer antihypertensive drugs, or higher blood pressure targets compared with lower targets. To avoid small early phase trials, studies were required to have at least 650 patient years of follow-up.

INFORMATION SOURCES

Searches were conducted in Embase, Medline, CENTRAL, and the Science Citation Index databases from inception until 14 April 2020.

MAIN OUTCOME MEASURES

The primary outcome was falls during trial follow-up. Secondary outcomes were acute kidney injury, fractures, gout, hyperkalaemia, hypokalaemia, hypotension, and syncope. Additional outcomes related to death and major cardiovascular events were extracted. Risk of bias was assessed using the Cochrane risk of bias tool, and random effects meta-analysis was used to pool rate ratios, odds ratios, and hazard ratios across studies, allowing for between study heterogeneity (τ2).

RESULTS

Of 15 023 articles screened for inclusion, 58 randomised controlled trials were identified, including 280 638 participants followed up for a median of 3 (interquartile range 2-4) years. Most of the trials (n=40, 69%) had a low risk of bias. Among seven trials reporting data for falls, no evidence was found of an association with antihypertensive treatment (summary risk ratio 1.05, 95% confidence interval 0.89 to 1.24, τ2=0.009). Antihypertensives were associated with an increased risk of acute kidney injury (1.18, 95% confidence interval 1.01 to 1.39, τ2=0.037, n=15), hyperkalaemia (1.89, 1.56 to 2.30, τ2=0.122, n=26), hypotension (1.97, 1.67 to 2.32, τ2=0.132, n=35), and syncope (1.28, 1.03 to 1.59, τ2=0.050, n=16). The heterogeneity between studies assessing acute kidney injury and hyperkalaemia events was reduced when focusing on drugs that affect the renin angiotensin-aldosterone system. Results were robust to sensitivity analyses focusing on adverse events leading to withdrawal from each trial. Antihypertensive treatment was associated with a reduced risk of all cause mortality, cardiovascular death, and stroke, but not of myocardial infarction.

CONCLUSIONS

This meta-analysis found no evidence to suggest that antihypertensive treatment is associated with falls but found evidence of an association with mild (hyperkalaemia, hypotension) and severe adverse events (acute kidney injury, syncope). These data could be used to inform shared decision making between doctors and patients about initiation and continuation of antihypertensive treatment, especially in patients at high risk of harm because of previous adverse events or poor renal function.

REGISTRATION

PROSPERO CRD42018116860.

Stopping Renin-Angiotensin System Inhibitors in Patients with Advanced CKD and Risk of Adverse Outcomes: A Nationwide Study

BACKGROUND

It is unknown whether stopping renin-angiotensin system (RAS) inhibitor therapy in patients with advanced CKD affects outcomes.

METHODS

We studied patients referred to nephrologist care, listed on the Swedish Renal Registry during 2007-2017, who developed advanced CKD (eGFR<30 ml/min per 1.73 m²) while on RAS inhibitor therapy. Using target trial emulation techniques on the basis of cloning, censoring, and weighting, we compared the risks of stopping within 6 months and remaining off treatment versus continuing RAS inhibitor therapy. These included risks of subsequent 5-year all-cause mortality, major adverse cardiovascular events, and initiation of kidney replacement therapy (KRT).

RESULTS

Of 10,254 prevalent RAS inhibitor users (median age 72 years, 36% female) with new-onset eGFR <30 ml/min per 1.73 m², 1553 (15%) stopped RAS inhibitor therapy within 6 months. Median eGFR was 23 ml/min per 1.73 m². Compared with continuing RAS inhibition, stopping this therapy was associated with a higher absolute 5-year risk of death (40.9% versus 54.5%) and major adverse cardiovascular events (47.6% versus 59.5%), but with a lower risk of KRT (36.1% versus 27.9%); these corresponded to absolute risk differences of 13.6 events per 100 patients, 11.9 events per 100 patients, and -8.3 events per 100 patients, respectively. Results were consistent whether patients stopped RAS inhibition at higher or lower eGFR, across prespecified subgroups, after adjustment and stratification for albuminuria and potassium, and when modeling RAS inhibition as a time-dependent exposure using a marginal structural model.

CONCLUSIONS

In this nationwide observational study of people with advanced CKD, stopping RAS inhibition was associated with higher absolute risks of mortality and major adverse cardiovascular events, but also with a lower absolute risk of initiating KRT.

Nitric oxide signalling in kidney regulation and cardiometabolic health

The prevalence of cardiovascular and metabolic disease coupled with kidney dysfunction is increasing worldwide. This triad of disorders is associated with considerable morbidity and mortality as well as a substantial economic burden. Further understanding of the underlying pathophysiological mechanisms is important to develop novel preventive or therapeutic approaches. Among the proposed mechanisms, compromised nitric oxide (NO) bioactivity associated with oxidative stress is considered to be important. NO is a short-lived diatomic signalling molecule that exerts numerous effects on the kidneys, heart and vasculature as well as on peripheral metabolically active organs. The enzymatic L-arginine-dependent NO synthase (NOS) pathway is classically viewed as the main source of endogenous NO formation. However, the function of the NOS system is often compromised in various pathologies including kidney, cardiovascular and metabolic diseases. An alternative pathway, the nitrate-nitrite-NO pathway, enables endogenous or dietary-derived inorganic nitrate and nitrite to be recycled via serial reduction to form bioactive nitrogen species, including NO, independent of the NOS system. Signalling via these nitrogen species is linked with cGMP-dependent and independent mechanisms. Novel approaches to restoring NO homeostasis during NOS deficiency and oxidative stress have potential therapeutic applications in kidney, cardiovascular and metabolic disorders.

Effects of dapagliflozin on major adverse kidney and cardiovascular events in patients with diabetic and non-diabetic chronic kidney disease: a prespecified analysis from the DAPA-CKD trial

BACKGROUND

Dapagliflozin reduces the risk of kidney failure and heart failure in patients with chronic kidney disease. We aimed to investigate the effects of dapagliflozin on kidney, cardiovascular, and mortality outcomes according to presence or absence of type 2 diabetes and according to underlying cause of chronic kidney disease, reported as diabetic nephropathy, chronic glomerulonephritides, ischaemic or hypertensive chronic kidney disease, or chronic kidney disease of other or unknown cause.

METHODS

DAPA-CKD was a multicentre, double-blind, placebo-controlled, randomised trial done at 386 study sites in 21 countries, in which participants with a urinary albumin-to-creatinine ratio of 200-5000 mg/g and an estimated glomerular filtration rate (eGFR) of 25-75 mL/min per 1·73m² were randomly assigned (1:1) to dapagliflozin 10 mg once daily or matching placebo, as an adjunct to standard care. The primary outcome was a composite of sustained decline in eGFR of at least 50%, end-stage kidney disease, or kidney-related or cardiovascular death. Secondary efficacy outcomes were a kidney-specific composite (the same as the primary outcome but excluding cardiovascular death), a composite of cardiovascular death or hospital admission for heart failure, and all-cause mortality. In this study, we conducted a prespecified subgroup analysis of the DAPA-CKD primary and secondary endpoints by presence or absence of type 2 diabetes and by aetiology of chronic kidney disease. DAPA-CKD is registered with ClinicalTrials.gov, NCT03036150.

FINDINGS

The study took place between Feb 2, 2017, and June 12, 2020. 4304 participants were randomly assigned (2152 to dapagliflozin and 2152 to placebo) and were followed up for a median of 2·4 years (IQR 2·0-2·7). Overall, 2906 (68%) participants had a diagnosis of type 2 diabetes, of whom 396 (14%) had chronic kidney disease ascribed to causes other than diabetic nephropathy. The relative risk reduction for the primary composite outcome with dapagliflozin was consistent in participants with type 2 diabetes (hazard ratio [HR] 0·64, 95% CI 0·52-0·79) and those without diabetes (0·50, 0·35-0·72; p_interaction=0·24). Similar findings were seen for the secondary outcomes: kidney-specific composite outcome (0·57 [0·45-0·73] vs 0·51 [0·34-0·75]; P_interaction=0·57), cardiovascular death or hospital admission for heart failure (0·70 [0·53-0·92] vs 0·79 [0·40-1·55]; P_interaction=0·78), and all-cause mortality (0·74 [0·56-0·98] vs 0·52 [0·29-0·93]; P_interaction=0·25). The effect of dapagliflozin on the primary outcome was also consistent among patients with diabetic nephropathy (n=2510; HR 0·63, 95% CI 0·51-0·78), glomerulonephritides (n=695; 0·43, 0·26-0·71), ischaemic or hypertensive chronic kidney disease (n=687; 0·75, 0·44-1·26), and chronic kidney disease of other or unknown cause (n=412; 0·58, 0·29-1·19; P_interaction=0·53), with similar consistency seen across the secondary outcomes. The proportions of participants in the dapagliflozin and placebo groups who had serious adverse events or discontinued study drug due to adverse events did not vary between those with and those without type 2 diabetes.

INTERPRETATION

Dapagliflozin reduces the risks of major adverse kidney and cardiovascular events and all-cause mortality in patients with diabetic and non-diabetic chronic kidney disease.

FUNDING

AstraZeneca.

The dapagliflozin and prevention of adverse outcomes in chronic kidney disease (DAPA-CKD) trial: baseline characteristics

Background

The Dapagliflozin and Prevention of Adverse outcomes in Chronic Kidney Disease (DAPA-CKD; NCT03036150) trial was designed to assess the effect of the sodium–glucose co-transporter 2 (SGLT2) inhibitor dapagliflozin on kidney and cardiovascular events in participants with CKD with and without type 2 diabetes (T2D). This analysis reports the baseline characteristics of those recruited, comparing them with those enrolled in other trials.

Methods

In DAPA-CKD, 4304 participants with a urinary albumin:creatinine ratio (UACR) ≥200 mg/g and estimated glomerular filtration rate (eGFR) between 25 and 75 mL/min/1.73 m² were randomized to dapagliflozin 10 mg once daily or placebo. Mean eGFR was 43.1 mL/min/1.73 m² and median UACR was 949 mg/g (108 mg/mmol).

Results

Overall, 2906 participants (68%) had a diagnosis of T2D and of these, 396 had CKD ascribed to a cause other than diabetes. The most common causes of CKD after diabetes (n = 2510) were ischaemic/hypertensive nephropathy (n = 687) and chronic glomerulonephritis (n = 695), of which immunoglobulin A nephropathy (n = 270) was the most common. A total of 4174 participants (97%) were receiving an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, 1882 (43.7%) diuretics, 229 (5.3%) mineralocorticoid receptor antagonists and 122 (2.8%) glucagon-like peptide 1 receptor agonists. In contrast to the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE), the DAPA-CKD trial enrolled participants with CKD due to diabetes and to causes other than diabetes. The mean eGFR of participants in the DAPA-CKD trial was 13.1 mL/min/1.73 m² lower than in CREDENCE, similar to that in the Finerenone in Reducing Kidney Failure and Disease Progression in DKD (FIDELIO-DKD) trial and the Study Of diabetic Nephropathy with AtRasentan (SONAR).

Conclusions

Participants with a wide range of underlying kidney diseases receiving renin–angiotensin system blocking therapy have been enrolled in the DAPA-CKD trial. The trial will examine the efficacy and safety of dapagliflozin in participants with CKD Stages 2–4 and increased albuminuria, with and without T2D.

[Mineralcorticoid receptor blockers in chronic kidney disease]

There are many experimental data supporting the involvement of aldosterone and mineralcorticoid receptor (MR) activation in the genesis and progression of chronic kidney disease (CKD) and cardiovascular damage. Many studies have shown that in diabetic and non-diabetic CKD, blocking the renin- angiotensin-aldosterone (RAAS) system with conversion enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARBs) decreases proteinuria, progression of CKD and mortality, but there is still a significant residual risk of developing these events. In subjects treated with ACEi or ARBs there may be an aldosterone breakthrough whose prevalence in subjects with CKD can reach 50%. Several studies have shown that in CKD, the aldosterone antagonists (spironolactone, eplerenone) added to ACEi or ARBs, reduce proteinuria, but increase the risk of hyperkalemia. Other studies in subjects treated with dialysis suggest a possible beneficial effect of antialdosteronic drugs on CV events and mortality. Newer potassium binders drugs can prevent / decrease hyperkalemia induced by RAAS blockade, and may reduce the high discontinuation rates or dose reduction of RAAS-blockers. The nonsteroidal MR blockers, with more potency and selectivity than the classic ones, reduce proteinuria and have a lower risk of hyperkalemia. Several clinical trials, currently underway, will determine the effect of classic MR blockers on CV events and mortality in subjects with stage 3b CKD and in dialysis patients, and whether in patients with type 2 diabetes mellitus and CKD, optimally treated and with high risk of CV and kidney events, the addition of finerenone to their treatment produces cardiorenal benefits. Large randomized trials have shown that sodium glucose type 2 cotransporter inhibitors (SGLT2i) reduce mortality and the development and progression of diabetic and nondiabetic CKD. There are pathophysiological arguments, which raise the possibility that the triple combination ACEi or ARBs, SGLT2i and aldosterone antagonist provide additional renal and cardiovascular protection.

It Comes As a Shock: Kidney Repair Using Shockwave Therapy

Chronic kidney disease is a global health care burden, yet clinically-proven treatments are limited. Low-intensity shockwave, which utilizes ≈10% of the energy levels used in clinically indicated shockwave lithotripsy, is a promising technique to ameliorate ischemia and regenerate tissues. It has been demonstrated to improve healing in tissues such as bone, muscle, myocardium, and kidney via several mechanisms, particularly through promoting neovascularization. Low-intensity shockwave stimulates mechanoreceptors located primarily in endothelial and proximal tubular cells and subsequently upregulates vascular endothelial growth factors. This, in turn, promotes angiogenesis and ameliorates renal hypoxia, inflammation, and fibrosis, and ultimately preserves renal function. Furthermore, low-intensity shockwave can stimulate release of homing factors to attract endothelial progenitor or stem cells into injured kidneys for tissue repair. These effects may be beneficial in several kidney disease models, including renal artery stenosis, diabetic kidney disease, and various chronic kidney diseases, although most studies reported to date have been performed in animal models. Because of its low energy intensity, the procedure is relatively tolerable and safe, yet, more clinical studies are needed to establish its efficacy beyond currently existing strategies. Therefore, low-intensity shockwave therapy emerges as an alternative therapeutic approach that may offer a promising noninvasive intervention for treating renal diseases. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02515461; NCT03602807; and NCT03445247.

The uraemic hypertensive patient: a therapeutic challenge—right you are (if you think so)

High blood pressure (BP) is a leading cause of chronic kidney disease (CKD) and at the same time represents its most frequent complication. High BP is an independent risk factor for advanced CKD; on the other hand, at least 40% of patients with normal glomerular filtration rate (GFR) and virtually all patients with GFR <30 mL/min are hypertensive. CKD and microalbuminuria are powerful risk factors for cardiovascular morbidity and mortality. Consequently, in uraemic hypertension, it is of utmost importance to carefully manage both high BP and microalbuminuria, in order to slow down the progression of kidney damage and to reduce the incidence of cardiovascular events. The first purpose of the medical treatment in hypertensive patients is to normalize BP, regardless of the drug used. Nevertheless, some drugs have an ‘additional’ nephroprotective effect at the same BP target achieved. In this regard, first-line drugs are definitely renin–angiotensin–aldosterone inhibitors, mainly for their proved efficacy in reducing hypertension-related kidney damage and proteinuria. Anyway, a combined approach (two or more drugs) is usually needed to achieve the optimal BP target and reduce the worsening of CKD.

Dietary intake, anthropometric measurements, biochemistry profile and their associations with chronic kidney disease and diabetes mellitus

The chronic kidney disease (CKD) and diabetes mellitus (DM) are considered a serious public health problem. The objective was investigating the association of DM with the anthropometric measures, biochemical profile and dietary intake in patients with CKD. Is a cross-sectional study done in 2017, with 51 patients previously diagnosed with CKD. We collect socio-demographic, lifestyle variables, anthropometric measurements, biochemical profile and dietary intake. We using the Kolmogorov–Smirnov test, followed by Pearson's χ² test and Student's t test. Data were analysed using several multivariable logistic regression models, including the socio-demographic, anthropometric, dietary intake and biochemical variable. Variables with P ≤ 0⋅20 in the univariate analyses were selected and kept in the block in the simple and multiple logistic regression analysis, to determine the differences between the categories and the factors associated with the presence of DM or not, remaining in the model final, only the significant variables (P ≤ 0⋅05). Each variable was adjusted for all other variables included in the univariate analysis. The strength of the association was assessed by the odds ratio and 95% confidence intervals (CI). The multivariate logistic regression analysis evidenced that the increase of 1 cm in waist circumference and 1 mg/dl in VLDL-c values increases the chance of DM, respectively, by 8⋅4% (OR 1⋅076; P 0⋅05) and 8⋅8% (OR 1⋅102; P 0⋅01). In contrast, an increase of 1 mg/dl in total cholesterol decreases the chance of developing DM by 3⋅1% (OR 0⋅965; P 0⋅01), that is, it becomes a protective factor. The present study identified the associations between overweight, dietary intake and biochemical tests.

Continued In-Hospital Angiotensin-Converting Enzyme Inhibitor and Angiotensin II Receptor Blocker Use in Hypertensive COVID-19 Patients Is Associated With Positive Clinical Outcome

Background

This study investigated continued and discontinued use of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARB) during hospitalization of 614 hypertensive laboratory-confirmed COVID-19 patients.

Methods

Demographics, comorbidities, vital signs, laboratory data, and ACEi/ARB usage were analyzed. To account for confounders, patients were substratified by whether they developed hypotension and acute kidney injury (AKI) during the index hospitalization.

Results

Mortality (22% vs 17%, P > .05) and intensive care unit (ICU) admission (26% vs 12%, P > .05) rates were not significantly different between non-ACEi/ARB and ACEi/ARB groups. However, patients who continued ACEi/ARBs in the hospital had a markedly lower ICU admission rate (12% vs 26%; P = .001; odds ratio [OR] = 0.347; 95% confidence interval [CI], .187–.643) and mortality rate (6% vs 28%; P = .001; OR = 0.215; 95% CI, .101–.455) compared to patients who discontinued ACEi/ARB. The odds ratio for mortality remained significantly lower after accounting for development of hypotension or AKI.

Conclusions

These findings suggest that continued ACEi/ARB use in hypertensive COVID-19 patients yields better clinical outcomes.

Management of proteinuria: blockade of the renin-angiotensin-aldosterone system

Proteinuria, in particular albuminuria, is a potentially significant modifiable risk factor for cardiovascular disease and the progression of kidney disease. Current treatment guidelines for albuminuria recommend a single renin–angiotensin–aldosterone inhibitor. This can be an ACE inhibitor or an angiotensin receptor antagonist. The routine use of combined renin–angiotensin–aldosterone inhibition for albuminuria is not supported by current evidence. Combination therapy is associated with higher rates of adverse events such as hyperkalaemia and progressive renal impairment.

Nephroprotection by SGLT2 Inhibition: Back to the Future?

The introduction of sodium/glucose cotransporter 2 inhibitors (SGLT2i) has opened new perspectives for the management of diabetic population at risk of or with chronic kidney disease (CKD). More important, recent, large real-world studies have repositioned the nephroprotective efficacy of SGLT2i emerged from randomized trials within the frame of effectiveness. Furthermore, the salutary effects of these agents may extend to the nondiabetic population according to the positive results of current studies. Nevertheless, the clear benefits of these agents on the prevention of organ damage contrast with their unexpected, limited use in clinical practice. One potential barrier is the acute decline in glomerular filtration rate (GFR) commonly observed at the beginning of treatment. This phenomenon is reminiscent of the early response to the traditional nephroprotective interventions, namely blood pressure lowering, dietary protein and salt restriction and the inhibition of the renin–angiotensin system. Under this perspective, the “check-mark” sign observed in the GFR trajectory over the first weeks of SGT2i therapy should renew interest on the very basic goal of CKD treatment, i.e., alleviate hyperfiltration in viable nephrons in order to prolong their function.

Not all proteinuria is created equal

Albuminuria acts as a marker of progressive chronic kidney disease and as an indicator for initiation of hypertension treatment via modulation of the renin-angiotensin-aldosterone system with angiotensin receptor blockers or angiotensin-converting enzyme inhibitors. However, the true significance of albuminuria has yet to be fully defined. Is it merely a marker of underlying pathophysiology, or does it play a causal role in the progression of kidney disease? The answer remains under debate. In this issue of the JCI, Bedin et al. used next-generation sequencing data to identify patients with chronic proteinuria who had biallelic variants in the cubilin gene (CUBN). Through investigation of these pathogenic mutations in CUBN, the authors have further illuminated the clinical implications of albuminuria.

Treatment strategies for hypertension in patients with type 1 diabetes

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is a chronic, autoimmune disease that is characterized by total absence of insulin production. Hypertension is a common comorbidity in T1DM with complex pathophysiology, while it is also a well-recognized risk factor for the development of cardiovascular disease (CVD), as well as other microvascular diabetic complications.

AREAS COVERED

The purpose of this review is to present the current definitions, epidemiological data and prevalence rates of hypertension in T1DM, as well as to describe current therapeutic options.

EXPERT OPINION

Hypertension affects around a third of the type 1 diabetic population, with higher prevalence rates in older individuals with longer disease duration. Although hypertension affects a substantial proportion of T1DM individuals, blood pressure control rates are disappointingly low. Alongside lifestyle modification, antihypertensive treatment should be initiated in those with blood pressure above 140/90 mmHg, with a systolic blood pressure target of 130 mmHg and lower, if tolerated. In those with established CVD or diabetic nephropathy, systolic blood pressure targets below 130 mmHg should be pursued. Initial pharmacotherapy should consist of a renin-angiotensin-aldosterone system inhibitor. There is an urgent need for good quality data regarding proper antihypertensive treatment initiation, optimal BP targets and optimal antihypertensive treatment for better clinical outcomes.

Effects of renin-angiotensin system blockers on renal and cardiovascular outcomes in patients with diabetic nephropathy: a meta-analysis of randomized controlled trials

PURPOSE

This study aimed to evaluate the effect f angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) on renal or cardiovascular outcomes in patients with diabetic nephropathy (DN).

METHODS

PubMed, Embase, and Cochrane Library were searched for randomized controlled trials (RCTs) evaluating the treatment effects of ACEI and ARB on renal or cardiovascular outcomes in patients with DN until August 2017. The outcomes included end-stage renal disease (ESRD), doubling of serum creatinine levels, all-cause mortality, major cardiovascular events (MACEs), myocardial infarction (MI), stroke, and cardiac death. Relative risks (RR) with 95% confidence intervals (CIs) were used for calculating the summary results using a random-effects model.

RESULTS

Twenty-four RCTs including 57,818 patients with DN and 891 events of ESRD, 1050 doubling of serum creatinine concentration, 4352 all-cause mortality, 6342 MACEs, 1073 MI, 2900 stroke, and 1674 cardiac deaths were reported. Overall, the summary results suggested that in patients with DN, receiving ACEI did not have a significant effect on ESRD, doubling of serum creatinine levels, all-cause mortality, MI, stroke, and cardiac death, while ACEI significantly reduced the risk of total MACEs. Furthermore, ARB therapy was associated with a low risk of ESRD and doubling of serum creatinine levels, while it did not differ significantly on all-cause mortality, MACEs, MI, stroke, and cardiac death in patients with DN.

CONCLUSIONS

Patients with DN receiving ACEI had significantly reduced the risk of total MACEs, and ARB could reduce the incidence of ESRD and the doubling of serum creatinine levels.

Effects of mineralocorticoid receptor antagonists in proteinuric kidney disease: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Reductions in albuminuria of more than 30% are considered a strong marker of delay of chronic kidney disease (CKD) progression. Single renin-angiotensin system (RAS) blockade represents the cornerstone of CKD treatment. However, as CKD progression still occurs, other nephroprotective options were explored; mineralocorticoid receptor antagonists (MRA) were tested with generally positive results.

METHODS

We conducted a systematic review and meta-analysis on the effects of MRAs on albuminuria/proteinuria, and adverse events, such as change in renal function and hyperkalemia incidence. A detailed search in electronic databases, clinical trial registries and grey literature was performed to retrieve randomized controlled trials (RCTs) in which administration of an MRA alone or on-top of ACEi/ARB was compared with placebo or active treatment.

RESULTS

Of the 45 initially identified reports, 31, with 2767 participants, were included in analysis of the primary outcome. The use of MRAs (alone or on top of RAS blockade) compared with placebo decreased urine albumin-to-creatinine ratio (UACR) by -24.55% (95% CI -29.57 to -19.53%), urine protein-to-creatinine ratio (UPCR) by -53.93% (95% CI -79% to -28.86%) and 24 h albumin excretion by -32.47% (95% CI -41.1 to -23.85%). MRAs also reduced UACR by -22.48% (95% CI -24.51 to -20.44%) compared with calcium-channel-blockers (CCBs), whereas no differences were found compared with a second ACEi/ARB or nonpotassium-sparing diuretics. Addition of an MRA was associated with change in estimated glomerular filtration rate (eGFR) of -2.38 ml/min per 1.73 m (95% CI -3.51 to -1.25), rise in potassium by 0.22 mEq/l (95% CI 0.16-0.28 mEq/l) and a 2.6-fold increase in hyperkalemia risk (RR 2.63, 95% CI 1.69-4.08) compared with placebo/active control.

CONCLUSION

Use of MRAs alone or on top of RAS blockade confers important antiproteinuric effects in patients with CKD, with a slight increase in mean potassium levels.