Cardiovascular and Renal Outcomes Associated With Hyperkalemia in Chronic Kidney Disease: A Hospital-Based Cohort Study

Characteristics, Risk Factors, and Outcomes in Acute Kidney Injury Patients: A Retrospective Cross-Sectional Study, Palestine

Background

Acute kidney injury (AKI) is a major medical problem affecting patients' quality of life and healthcare costs.

Objectives

This study evaluated the severity, risk factors, and outcomes of patients diagnosed with acute kidney injury (AKI), including community-acquired AKI (CA-AKI) and hospital-acquired AKI (HA-AKI), who were admitted to tertiary institutions in Palestine.

Methods

This retrospective cross-sectional study was conducted at multiple tertiary care hospitals in Palestine by reviewing patient charts from January 2020 to March 2023. The study included all patients aged ≥18 years who were admitted to the hospital and diagnosed with AKI at admission (CA-AKI) or who developed AKI 48 hours after admission (HA-AKI). Patients with incomplete medical records and those with no reported creatinine levels during their stay, pregnant women, kidney transplant patients, and end-stage renal disease patients were excluded. Data were analyzed using SPSS v22.0. The incidence of AKI in each group was compared using the chi-squared test.

Results

This study included 259 participants. HA-AKI was present in 27.3% of the patients, while CA-AKI was 72.7%. The most common stage among patients was stage 3 (55.7%, HA-AKI) (42.9%, CA-AKI), and the most common comorbidity contributing to AKI was CKD. NSAIDs, ACE-I/ARBs, and DIURETICs were the most nephrotoxic drugs contributing to AKI. Patients with hyperphosphatemia, hyperkalemia, severe metabolic acidosis, or stage 3 AKI require renal replacement therapy. In addition, our findings revealed a significant association among AKI mortality, age, and heart disease.

Conclusion

CA-AKI was more prevalent than HA-AKI in Palestinian patients admitted for AKI. Risk factors for AKI included diabetes, CKD, and medications (antibiotics, NSAID, diuretics, and ACE-I/ARB). Preventive measures, medication management, and disease state management are necessary to minimize AKI during hospital admission or in the community.

Risk of hyperkalaemia in patients with type 2 diabetes mellitus prescribed with SGLT2 versus DPP-4 inhibitors

AIMS

To investigate the risk of hyperkalaemia in new users of sodium-glucose cotransporter 2 (SGLT2) inhibitors vs. dipeptidyl peptidase-4 (DPP-4) inhibitors among patients with type 2 diabetes mellitus (T2DM).

METHODS AND RESULTS

Patients with T2DM who commenced treatment with an SGLT2 or a DPP-4 inhibitor between 2015 and 2019 were collected. A multivariable Cox proportional hazards analysis was applied to compare the risk of central laboratory-determined severe hyperkalaemia, hyperkalaemia, hypokalaemia (serum potassium ≥6.0, ≥5.5, and <3.5 mmol/L, respectively), and initiation of a potassium binder in patients newly prescribed an SGLT2 or a DPP-4 inhibitor. A total of 28 599 patients (mean age 60 ± 11 years, 60.9% male) were included after 1:2 propensity score matching, of whom 10 586 were new users of SGLT2 inhibitors and 18 013 of DPP-4 inhibitors. During a 2-year follow-up, severe hyperkalaemia developed in 122 SGLT2 inhibitor users and 325 DPP-4 inhibitor users. Use of SGLT2 inhibitors was associated with a 29% reduction in incident severe hyperkalaemia [hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.58-0.88] compared with DPP-4 inhibitors. Risk of hyperkalaemia (HR 0.81, 95% CI 0.71-0.92) and prescription of a potassium binder (HR 0.74, 95% CI 0.67-0.82) were likewise decreased with SGLT2 inhibitors compared with DPP-4 inhibitors. Occurrence of incident hypokalaemia was nonetheless similar between those prescribed an SGLT2 inhibitor and those prescribed a DPP-4 inhibitor (HR 0.90, 95% CI 0.81-1.01).

CONCLUSION

Our study provides real-world evidence that compared with DPP-4 inhibitors, SGLT2 inhibitors were associated with lower risk of hyperkalaemia and did not increase the incidence of hypokalaemia in patients with T2DM.

Novel Approaches in Chronic Renal Failure without Renal Replacement Therapy: A Review

Chronic kidney disease (CKD) is characterized by renal parenchymal damage leading to a reduction in the glomerular filtration rate. The inflammatory response plays a pivotal role in the tissue damage contributing to renal failure. Current therapeutic options encompass dietary control, mineral salt regulation, and management of blood pressure, blood glucose, and fatty acid levels. However, they do not effectively halt the progression of renal damage. This review critically examines novel therapeutic avenues aimed at ameliorating inflammation, mitigating extracellular matrix accumulation, and fostering renal tissue regeneration in the context of CKD. Understanding the mechanisms sustaining a proinflammatory and profibrotic state may offer the potential for targeted pharmacological interventions. This, in turn, could pave the way for combination therapies capable of reversing renal damage in CKD. The non-replacement phase of CKD currently faces a dearth of efficacious therapeutic options. Future directions encompass exploring vaptans as diuretics to inhibit water absorption, investigating antifibrotic agents, antioxidants, and exploring regenerative treatment modalities, such as stem cell therapy and novel probiotics. Moreover, this review identifies pharmaceutical agents capable of mitigating renal parenchymal damage attributed to CKD, targeting molecular-level signaling pathways (TGF-β, Smad, and Nrf2) that predominate in the inflammatory processes of renal fibrogenic cells.

Recent Progresses in Non-Dialysis Chronic Kidney Disease Patients with Hyperkalemia: Outcomes and Therapeutic Strategies

Chronic kidney disease (CKD) affects about 10% of the world's population. Hyperkalemia is a life-threatening complication in patients with CKD, as it is associated with adverse cardiovascular and kidney outcomes. There are still many challenges and questions to address to improve the currently available therapeutic strategies to treat hyperkalemia, such as how to approach the emergency management of hyperkalemia. In recent years, in addition to novel oral potassium binders, great progress has been made in the application of novel kidney protective strategies, such as mineralocorticoid receptor antagonists and sodium-glucose cotransporter 2 inhibitors (SGLT2i) in hyperkalemia therapy. This review will discuss the recent advances from clinical trials in the effective management of hyperkalemia in non-dialysis CKD patients, enhancing the knowledge of physicians and internists concerning these newer agents and providing a helpful reference for clinical practice.

Impact of chronic potassium binder treatment on the clinical outcomes in patients with hyperkalemia: Results of a nationwide hospital-based cohort study

Introduction: Hyperkalemia (HK) is a common disorder in patients with heart failure or chronic kidney disease, and potassium binders (PBs) are recommended to control serum potassium (S-K) levels. Although HK is often a chronic condition, short-term and intermittent PBs treatment has been largely applied to control S-K levels, and little is known about the impact of long-term and chronic PBs treatment on clinical outcomes. Method: This retrospective cohort study was conducted using a Japanese claims database (April 2008-September 2018). HK was defined as at least two S-K ≥5.1 mmol/L within a 12-month(M) interval. The index date was defined as the initial PB prescription date, and the S-K values were examined at 3M, 6M, and 12M after the index. The medication possession ratio (MPR) was used to evaluate the length of the prescribed period of PB, as prescription refill was not allowed in Japan. Clinical outcomes were analyzed by comparing MPR <80% to MPR ≥80% using Cox proportional hazards regression. Results: We found 4,321 patients with HK and were on initial PB treatments, and 993 and 3,328 patients were categorized in the MPR <80% and MPR ≥80% groups, respectively. The mean prescription days ±SD in the MPR <80% and MPR ≥80% groups were 114.7 ± 9.1 and 1151.2 ± 22.5, respectively. S-K value with adjustment by covariates in MPR <80% and MPR ≥80% groups were 5.62 (95% CI: 5.57-5.68) and 5.72 (95% CI: 5.68-5.76) at index followed by 4.65 (95% CI: 4.58-4.71) and 4.57 (95% CI: 4.51-4.62) at 3M, respectively. The hazard ratios of incidence rates in hospitalization was 1.41 (p < 0.001), introduction of renal replacement therapy was 1.25 (p < 0.003), recurrent HK was 1.67 (p < 0.001), and decreased eGFR was 1.41 (p < 0.001), respectively. Conclusion: These results indicate a higher risk of adverse outcomes when PBs were not prescribed chronically, whereas S-K levels were similarly controlled. Chronic control with continued PBs rather than temporary treatment may be associated with the reduction of adverse clinical outcomes in patients with HK.

Machine Learning Models Predicting Cardiovascular and Renal Outcomes and Mortality in Patients with Hyperkalemia

Hyperkalemia is associated with increased risks of mortality and adverse clinical outcomes. The treatment of hyperkalemia often leads to the discontinuation or restriction of beneficial but potassium-increasing therapy such as renin-angiotensin-aldosterone inhibitors (RAASi) and high-potassium diet including fruits and vegetables. To date, limited evidence is available for personalized risk evaluation in this heterogeneous and multifactorial pathophysiological condition. We developed risk prediction models using extreme gradient boosting (XGB), multiple logistic regression (LR), and deep neural network. Models were derived from a retrospective cohort of hyperkalemic patients with either heart failure or chronic kidney disease stage ≥3a from a Japanese nationwide database (1 April 2008−30 September 2018). Studied outcomes included all-cause death, renal replacement therapy introduction (RRT), hospitalization for heart failure (HHF), and cardiovascular events within three years after hyperkalemic episodes. The best performing model was further validated using an external cohort. A total of 24,949 adult hyperkalemic patients were selected for model derivation and internal validation. A total of 1452 deaths (16.6%), 887 RRT (10.1%), 1,345 HHF (15.4%), and 621 cardiovascular events (7.1%) were observed. XGB outperformed other models. The area under receiver operator characteristic curves (AUROCs) of XGB vs. LR (95% CIs) for death, RRT, HHF, and cardiovascular events were 0.823 (0.805−0.841) vs. 0.809 (0.791−0.828), 0.957 (0.947−0.967) vs. 0.947 (0.936−0.959), 0.863 (0.846−0.880) vs. 0.838 (0.820−0.856), and 0.809 (0.784−0.834) vs. 0.798 (0.772−0.823), respectively. In the external dataset including 86,279 patients, AUROCs (95% CIs) for XGB were: death, 0.747 (0.742−0.753); RRT, 0.888 (0.882−0.894); HHF, 0.673 (0.666−0.679); and cardiovascular events, 0.585 (0.578−0.591). Kaplan−Meier curves of the high-risk predicted group showed a statistically significant difference from that of the low-risk predicted groups for all outcomes (p < 0.005; log-rank test). These findings suggest possible use of machine learning models for real-world risk assessment as a guide for observation and/or treatment decision making that may potentially lead to improved outcomes in hyperkalemic patients while retaining the benefit of life-saving therapies.

Validation of a new instrument for measuring disease-specific quality of life: A pilot study among patients with chronic kidney disease and hyperkalemia

BACKGROUND

To prepare for a longitudinal study of the effects of potassium-lowering treatment on quality of life (QOL), we quantified the validity of a new disease-specific instrument for measuring QOL, using data from patients who had hyperkalemia (HK) due to chronic kidney disease (CKD) or chronic heart failure, and were also being treated with potassium binders (PBs).

METHODS

In this cross-sectional study, the participants were 98 patients at five outpatient clinics in Japan. The outcome measures were the Medical Outcomes Study 36-item short-form (SF-36), a widely used generic measure of QOL, and the Quality of Life Disease-specific Impact Scale (QDIS-7), a recently-developed disease-specific measure of QOL. Internal-consistency reliability was quantified, and factor analysis was done to confirm hypothesized QOL dimensions. Validation tests used two external criteria: CKD stage, and PB formulation. PB formulation was used because different formulations are associated with different degrees of patients' burden. Using a previously-described method, we computed the relative validity (RV) of the two measures.

RESULTS

Two factor scoring of the SF-36 and one factor scoring of the QDIS-7, as standardized from previous studies, were confirmed. The RVs showed that the QDIS-7 was much more valid than the SF-36, for discriminating between groups defined clinically (by CKD stage), and also between groups defined by PB formulation. Reliability was satisfactory: 0.73-0.95 for the SF-36 and 0.86 for the QDIS-7.

CONCLUSIONS

The QDIS-7 with CKD or PB attributions was more valid than the SF-36 for measuring the effects of CKD and of PB formulation on QOL.

Plasma Nitrate and Nitrite Kinetics after Single Intake of Beetroot Juice in Adult Patients on Chronic Hemodialysis and in Healthy Volunteers: A Randomized, Single-Blind, Placebo-Controlled, Crossover Study

Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate-nitrite-NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity.

Atrial Fibrillation and Clinical Outcomes in a Cohort of Hospitalized Patients with Sars-Cov-2 Infection and Chronic Kidney Disease

The aim of the study was to investigate the role of chronic kidney disease (CKD) on in-hospital mortality and on incident atrial fibrillation (AF) in patients infected with SARS-CoV-2. The incidence of acute kidney injury (AKI) was also investigated. Multivariable regression models were used to assess the association between renal function groups (estimated Glomerular Filtration Rate, eGFR, >60 mL/min, 30-59 mL/min, <30 mL/min) and in-hospital all-cause mortality and incident AF and AKI. A cohort of 2816 patients admitted in one year for COVID-19 disease in two large hospitals was analyzed. The independent predictors of mortality were severe CKD [HR 1.732 (95%CI 1.264-2.373)], older age [HR 1.054 (95%CI 1.044-1.065)], cerebrovascular disease [HR 1.335 (95%CI (1.016-1.754)], lower platelet count [HR 0.997 (95%CI 0.996-0.999)], higher C-reactive protein [HR 1.047 (95%CI 1.035-1.058)], and higher plasma potassium value 1.374 (95%CI 1.139-1.658). When incident AKI was added to the final survival model, it was associated with higher mortality [HR 2.202 (1.728-2.807)]. Incident AF was more frequent in patients with CKD, but in the multivariable model only older age was significantly related with a higher incidence of AF [OR 1.036 (95%CI 1.022-1.050)]. Incident AF was strongly associated with the onset of AKI [HR 2.619 (95%CI 1.711-4.009)]. In this large population of COVID-19 patients, the presence of severe CKD was an independent predictor of in-hospital mortality. In addition, patients who underwent AKI during hospitalization had a doubled risk of death. Incident AF became more frequent as eGFR decreased and it was significantly associated with the onset of AKI.