Novel Therapies in Diabetic Kidney Disease and Risk of Hyperkalemia: A Review of the Evidence From Clinical Trials

SGLT2 Inhibitors and Risk for Hyperkalemia Among Individuals Receiving RAAS Inhibitors

Importance

Hyperkalemia is a common complication of taking a renin-angiotensin-aldosterone system inhibitor (RAASi). Post hoc analyses of large randomized clinical trials suggested that the addition of sodium-glucose cotransporter 2 inhibitors (SGLT2i) may attenuate this risk. It is unknown if this observation extends to daily clinical practice.

Objective

To evaluate the association between SGLT2i initiation and hyperkalemia in individuals receiving RAASi with a background of diabetes, heart failure, or chronic kidney disease.

Design, Setting, and Participants

This population-based retrospective cohort study was conducted in Ontario, Canada, from July 1, 2015, to June 30, 2021. The cohort comprised adults 66 years and older who were prescribed a RAASi and had a history of diabetes or heart failure, an estimated glomerular filtration rate of less than 45 mL/min/1.73 m2, and/or a urine albumin to creatinine ratio of greater than 30 mg/mmol. The data were analyzed between March 28, 2023, and March 22, 2024.

Exposure

The study exposure was a new prescription of an SGLT2i compared to noninitiation of an SGLT2i. Inverse probability of treatment weighting by a propensity score for the receipt of SGLT2i was used to achieve balance of baseline covariates in both exposure groups.

Main Outcomes and Measures

The primary study outcome was hyperkalemia, defined as a serum potassium of greater than 5.5 mEq/L or an administrative code for an inpatient or outpatient encounter with hyperkalemia within 1 year of the index date.

Results

A total of 20 063 individuals who initiated an SGLT2i (mean [SD] age, 76.9 [6.6] years; 12 020 [59.9%] male) were compared to a pseudopopulation of 19 781 nonusers (mean [SD] age, 76.8 [7.0] years; 11 731 [59.3%] male). In the overall cohort, 95% had diabetes, 17% had heart failure, and 32% had stage 3 to 5 chronic kidney disease. SGLT2i initiation was associated with a lower risk of hyperkalemia (hazard ratio, 0.89 [95% CI, 0.82-0.96]). SGLT2i users had a significantly lower rate of RAASi discontinuation compared to nonusers (36% vs 45%; P < .001).

Conclusions and Relevance

This cohort study demonstrated that, among individuals with diabetes, heart failure, or chronic kidney disease who were receiving a RAASi, SGLT2i initiation was associated with a lower risk of hyperkalemia and RAASi discontinuation.

Targeting RAC1 might be a potential therapeutic strategy for diabetic kidney disease: a Mendelian randomization study

PURPOSE

This study aimed to ascertain the causal association between Ras-related C3 botulinum toxin substrate 1 (RAC1) and the incidence and progression of diabetic kidney disease (DKD) through Mendelian randomization analysis.

METHODS

RAC1 expression, evaluated using expression quantitative trait loci data from the eQTLGen Consortium, was served as the exposure variable. Outcomes encompassed the risk of DKD, end-stage renal disease (ESRD), albuminuria assessed by the urinary albumin-to-creatinine ratio (ACR), and estimated glomerular filtration rate (eGFR) among individuals with diabetes. Causal associations were computed using the inverse variance weighted (IVW), weighted median, and MR-PRESSO models. Additionally, we conducted analyses for heterogeneity, horizontal pleiotropy, and sensitivity.

RESULTS

This study revealed a causal association between the genetic activation of RAC1 and an elevated risk of DKD among individuals with diabetes [IVW, odds ratio (OR) = 1.28, 95% confidence intervals (CI) 1.08-1.51, P = 0.004]. Furthermore, increased expression of RAC1 was linked to a higher risk of ESRD (IVW, OR = 1.20, 95% CI 1.02-1.43, P = 0.032). Excessive RAC1 expression was causally associated with elevated ACR (IVW, β = 0.052, 95% CI 0.003-0.100, P = 0.036). However, the analysis regarding RAC1 and eGFR showed significant heterogeneity and pleiotropy, with no discernible causal relationship.

CONCLUSIONS

These findings suggested a positive correlation between the genetic activation of RAC1 and the incidence of DKD, the risk of ESRD, and exacerbated albuminuria among individuals with diabetes. Targeting RAC1 might potentially serve as a therapeutic strategy for DKD.

Incidence of hyperkalemia RAASi and SGLT-2i treatment in individuals with diabetic kidney disease: a systematic review and network meta-analysis

Background

This study aims to evaluate the incidence of hyperkalemia and serum potassium levels associated with the use of sodium-glucose cotransporter-2 inhibitors (SGLT-2i), renin-angiotensin-aldosterone system inhibitors (RAASi) and concurrent use of these medications in individuals with diabetic kidney disease (DKD).

Methods

A comprehensive systematic search was performed in EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, Scopus, and PubMed database, covering studies up to March 2024. Relevant randomized controlled trials (RCT) included adults with DKD who were treated with SGLT-2i and RAASi or their combination, with a minimum follow-up duration of 12 weeks. The primary outcomes assessed were the incidence of hyperkalemia and serum potassium levels were the primary outcomes assessed. The surface under the cumulative ranking curves (SUCRA) was utilized for ranking purposes.

Results

The study included 36 trials, encompassing 45,120 participants, comparing various interventions. SGLT-2i (SUCRA = 88.5%) was found to significantly reduce the risk of hyperkalemia. In contrast, the combination of ACEI/ARB + MRA (SUCRA = 5.7%) increased the risk of hyperkalemia. However, when SGLT-2i was added to the ACEI/ARB + MRA regimen, the incidence of hyperkalemia was found to decrease. Subgroup analyses on MRA showed that ACEI/ARB + spironolactone posed the highest risk of hyperkalemia. ACEI/ARB + SGLT-2i mitigated serum potassium level.

Conclusion

SGLT-2i was effective in reducing the incidence of hyperkalemia incidence, whereas a combination of ACEI/ARB and MRA might elevate the incidence of hyperkalemia in individuals with DKD.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier CRD42024552810.

Aldosterone Synthase Inhibitors for Cardiorenal Protection: Ready for Prime Time?

BACKGROUND

Aldosterone is the principal mineralocorticoid hormone and the final effector of the renin-angiotensin-aldosterone system. This hormone is primarily synthesized by the CYP11B2 enzyme and produced by the adrenal zona glomerulosa. Through genomic and non-genomic effects, it plays an important role in cardiovascular and renal disease. To counteract aldosterone-mediated damage, steroidal mineralocorticoid receptor antagonists are recommended by international guidelines, but endocrine side effects often limit their use in a substantial proportion of patients. Conversely, nonsteroidal mineralocorticoid receptor antagonists, with an improved selectivity and safety profile, are gaining a prominent position among therapeutic pillars. However, blocking the mineralocorticoid receptors does not completely inhibit aldosterone effects because of escape mechanisms and non-genomic activity. Thus, inhibiting aldosterone synthesis could be a promising strategy to prevent aldosterone-mediated cardiorenal damage. The limited specificity for CYP11B2 and side effects due to off-target activity hampered the development of first-generation aldosterone synthase inhibitors (ASIs).

SUMMARY

The development of highly specific ASIs led to successful clinical trials in patients with resistant and uncontrolled hypertension. Additionally, a recent randomized clinical trial showed a significant benefit of ASIs in patients with chronic kidney disease and albuminuria.

KEY MESSAGES

The strength of the clinical evidence collected so far is still limited, and larger outcome-based clinical trials are needed to confirm the promising role of ASIs in cardiorenal damage.

Cell Division Cycle 42 Improves Renal Functions, Fibrosis, Th1/Th17 Infiltration and Inflammation to Some Degree in Diabetic Nephropathy

Our two previous studies observed that cell division cycle 42 (CDC42) was lower and correlated with improved renal function and inflammation in diabetic nephropathy (DN) patients, and CDC42 inhibited renal tubular epithelial cell fibrosis and inflammation under high glucose condition. Sequentially, this current study aimed to investigate the effect of CDC42 on improving renal function, fibrosis, and inflammation in DN mice, and its interaction with T cell receptor (TCR) related pathways. Mice were treated by streptozotocin to construct early-stage DN model, then transfected with CDC42 overexpression adenovirus, followed by simultaneous treatment of LY294002 (PI3K/AKT inhibitor) and CI-1040 (ERK inhibitor), respectively. CDC42 reduced blood glucose, creatinine, and 24 h urine protein in DN mice, but only showed a tendency to decrease blood urea nitrogen without statistical significance. Hematoxylin&eosin staining revealed that CDC42 descended the glomerular volume, basement membrane thickness, and inflammatory cell infiltration in kidney. Meanwhile, CDC42 lowered fibronectin, TGF-β1, and Collagen I expressions in kidney, but not decreased α-SMA significantly. Besides, CDC42 decreased T-helper (Th) 1 and Th17 cells in kidney, and reduced serum IFN-γ, IL-1β, IL-17A, and TNF-α but not IL-6. Regarding TCR-related pathways, CDC42 activated AKT and ERK pathways but not JNK pathway. However, the treatment of LY294002 and CI-1040 had limited effect on attenuating CDC42's functions on renal function and fibrotic markers. CDC42 improves renal functions, fibrosis, Th1/Th17 infiltration and inflammation to some degree in DN mice, these functions may be independent to AKT and ERK pathways.

Effects of Sodium-Glucose Cotransporter 2 Inhibitors in Diabetic and Non-Diabetic Patients with Advanced Chronic Kidney Disease in Peritoneal Dialysis on Residual Kidney Function: In Real-World Data

Background and Objectives: Peritoneal dialysis (PD) is a renal replacement therapy modality in which the dialysis dose can be individually adapted according to the patients' residual kidney function (RKF). RKF is a crucial factor for technique and patient survival. Pharmacological strategies aimed at slowing the loss of RKF in patients on PD are limited. Therefore, we aimed to assess the potential effects and safety of sodium-glucose cotransporter 2 (SGLT-2) inhibitors on the preservation of RKF in patients with and without type 2 diabetes mellitus (T2DM) on PD during an average follow-up of 6 months. Materials and Methods: In this retrospective observational, single-center study on real-world data, we included patients from the Peritoneal Dialysis Unit of the Hospital General Universitario de Ciudad Real, who started treatment with SGLT-2 inhibitors during the period from December 2022 to December 2023. Data on analytical and clinical parameters, RKF, and peritoneal membrane transport function were retrospectively collected at months 0, 3, and 6. Results: Out of 31 patients in our unit, 16 prevalent patients initiated treatment with SGLT-2 inhibitors (13 empagliflozin and 3 dapagliflozin). A total of 62.5% were male and the mean age was 67.3 years. The baseline peritoneal ultrafiltration was higher in the non-diabetic patient (NDMP) group than in the diabetic patient (DMP) group. However, the residual diuresis volume, 24 h residual renal clearance rate of urea in urine, and 24 h proteinuria were higher in the DMP group than in the NDMP group. At the sixth month, patients in both groups preserved RKF and diuresis, with a trend towards a non-significant reduction in proteinuria and blood pressure. Only two patients of the DMP group presented adverse effects. Conclusions: The use of SGLT-2 inhibitors in our sample of patients with and without T2DM on PD appears to be safe and effective to preserve RKF.

Patient Characteristics and Outcomes of Hospitalized Chronic Kidney Disease Patients with and without Type 2 Diabetes Mellitus: Observations from the German Claims Data-Based Cohort of the CaReMe-CKD Multinational Study

Introduction

Type 2 diabetes mellitus (T2DM) is a leading cause of chronic kidney disease (CKD) globally. Both conditions substantially worsen patients' prognosis. Current data on German in-hospital CKD cohorts are scarce. The multinational CaReMe study was initiated to evaluate the current epidemiology and healthcare burden of cardiovascular, renal and metabolic diseases. In this substudy, we share real-world data on CKD inpatients stratified for coexisting T2DM derived from a large German hospital network.

Methods

This study used administrative data of inpatient cases from 89 Helios hospitals from 01/01/2016 to 28/02/2022. Data were extracted from ICD-10-encoded discharge diagnoses and OPS-encoded procedures. The first case meeting a previously developed CKD definition (defined by ICD-10- and OPS-codes) was considered the index case for a particular patient. Subsequent hospitalizations were analysed for readmission statistics. Patient characteristics and pre-defined endpoints were stratified for T2DM at index case.

Results

In total, 48,011 patients with CKD were included in the present analysis (mean age ± standard deviation, 73.8 ± 13.1 years; female, 44%) of whom 47.9% had co-existing T2DM. Patients with T2DM were older (75 ± 10.6 vs 72.7 ± 14.9 years, p < 0.001), but gender distribution was similar to patients without T2DM. The burden of cardiovascular disease was increased in patients with T2DM, and index and follow-up in-hospital mortality rates were higher. Non-T2DM patients were characterised by more advanced CKD at baseline. Patients with T2DM had consistently higher readmission numbers for all events of interest, except for readmissions due to kidney failure/dialysis, which were more common in non-T2DM patients.

Conclusion

In this study, we present recent data on hospitalized patients with CKD in Germany. In this CKD cohort, nearly half had T2DM, which substantially affected cardiovascular disease burden, rehospitalization frequency and mortality. Interestingly, non-diabetic patients had more advanced underlying renal disease, which affected renal outcomes.

Role of Uremic Toxins, Oxidative Stress, and Renal Fibrosis in Chronic Kidney Disease

Affecting millions of people worldwide, chronic kidney disease is a serious medical problem. It results in a decrease in glomerular filtration rate below 60 mL/min/1.73 m, albuminuria, abnormalities in urine sediment and pathologies detected by imaging studies lasting a minimum of 3 months. Patients with CKD develop uremia, and as a result of the accumulation of uremic toxins in the body, patients can be expected to suffer from a number of medical consequences such as progression of CKD with renal fibrosis, development of atherosclerosis or increased incidence of cardiovascular events. Another key element in the pathogenesis of CKD is oxidative stress, resulting from an imbalance between the production of antioxidants and the production of reactive oxygen species. Oxidative stress contributes to damage to cellular proteins, lipids and DNA and increases inflammation, perpetuating kidney dysfunction. Additionally, renal fibrogenesis involving the accumulation of fibrous tissue in the kidneys occurs. In our review, we also included examples of forms of therapy for CKD. To improve the condition of CKD patients, pharmacotherapy can be used, as described in our review. Among the drugs that improve the prognosis of patients with CKD, we can include: GLP-1 analogues, SGLT2 inhibitors, Finerenone monoclonal antibody-Canakinumab and Sacubitril/Valsartan.

Managing hyperkalemia in patients with heart failure on guideline-directed medical therapy: challenges and opportunities

Heart failure is a chronic and invalidating syndrome that affects tens of millions of people worldwide with significant socio-economic ramifications for the health care systems. Significant progress in the understanding of the pathophysiology of heart failure has allowed the gradual introduction of several drug classes for the management of such patients. Beta-blockers, mineralocorticoid receptor antagonists, angiotensin receptor neprilysin inhibitors, and sodium-glucose-cotransporter 2 inhibitors are all considered pillars of the guideline-directed medical therapy for heart failure. Despite remarkable improvements in the morbidity and mortality of heart failure, however, many patients still develop clinically significant hyperkalemia during combined treatment with those four pharmacological pillars. The consequence is often a down-titration or discontinuation of one or more crucial drugs, which in turns leads to a considerable increase in the risk of cardiovascular events, dialysis, and all-cause mortality. This paper will explore novel approaches for the management of hyperkalemia in heart failure, including closer monitoring of potassium levels, early review of drugs that might increase the risk of hyperkalemia, and pharmacological treatment of hyperkalemia, with a special emphasis on sodium-glucose-cotransporter 2 inhibitors and potassium-binding agents, including patiromer and sodium zirconium cyclosilicate.

SGLT2 inhibitors in peritoneal dialysis: a promising frontier toward improved patient outcomes

Peritoneal dialysis (PD) stands as an important modality among kidney replacement therapies for end-stage kidney disease, offering patients remarkable flexibility and autonomy. Despite its widespread use, challenges such as glucose-related complications, peritoneal membrane fibrosis, declining renal function, and cardiovascular risks persist, necessitating innovative therapeutic approaches. Sodium–glucose cotransporter 2 (SGLT2) inhibitors, originally developed for treating type 2 diabetes mellitus, have recently shown promise as add-on therapy for patients with diabetic and non-diabetic chronic kidney disease (CKD), even in advanced stages. This review describes the potential role of SGLT2 inhibitors as a breakthrough therapeutic option in PD, emphasizing their ability to address unmet clinical needs and improve patient outcomes. The multiple effects of SGLT2 inhibitors in CKD, including metabolic modulation, antihypertensive, diuretic, anemia-reducing, antioxidant, and antiinflammatory properties, are reviewed in the context of PD challenges. Additionally, the potentially protective influence of SGLT2 inhibitors on the integrity of the peritoneal membrane and the transport of solutes and water in the peritoneum are emphasized. Despite these encouraging results, the paper highlights the potential risks associated with SGLT2 inhibitors in PD and emphasizes the need for cautious and thorough investigation of dosing, long-term safety considerations, and patient-specific factors through comprehensive clinical trials. Looking forward, the review argues for well-designed studies to evaluate the expanded safety profile of SGLT2 inhibitors in PD, with particular attention paid to peritoneal membrane integrity and overall patient outcomes.