Capacity for the management of kidney failure in the International Society of Nephrology Oceania and South East Asia (OSEA) region: report from the 2023 ISN Global Kidney Health Atlas (ISN-GKHA)

The International Society of Nephrology (ISN) region of Oceania and South East Asia (OSEA) is a mix of high- and low-income countries, with diversity in population demographics and densities. Three iterations of the ISN-Global Kidney Health Atlas (GKHA) have been conducted, aiming to deliver in-depth assessments of global kidney care across the spectrum from early detection of CKD to treatment of kidney failure. This paper reports the findings of the latest ISN-GKHA in relation to kidney-care capacity in the OSEA region. Among the 30 countries and territories in OSEA, 19 (63%) participated in the ISN-GKHA, representing over 97% of the region's population. The overall prevalence of treated kidney failure in the OSEA region was 1203 per million population (pmp), 45% higher than the global median of 823 pmp. In contrast, kidney replacement therapy (KRT) in the OSEA region was less available than the global median (chronic hemodialysis, 89% OSEA region vs. 98% globally; peritoneal dialysis, 72% vs. 79%; kidney transplantation, 61% vs. 70%). Only 56% of countries could provide access to dialysis to at least half of people with incident kidney failure, lower than the global median of 74% of countries with available dialysis services. Inequalities in access to KRT were present across the OSEA region, with widespread availability and low out-of-pocket costs in high-income countries and limited availability, often coupled with large out-of-pocket costs, in middle- and low-income countries. Workforce limitations were observed across the OSEA region, especially in lower-middle-income countries. Extensive collaborative work within the OSEA region and globally will help close the noted gaps in kidney-care provision.

Use of kidney failure risk equation as a tool to evaluate referrals from primary care to specialist nephrology care

BACKGROUND

With rising costs and burden of chronic kidney disease (CKD), timely referral of patients to a kidney specialist is crucial. Currently, Kidney Health Australia (KHA) uses a 'heat map' based on severity and not future risk of kidney failure, whereas the kidney failure risk equation (KFRE) score predicts future risk of progression.

AIMS

Evaluate whether a KFRE score assists with timing of CKD referrals.

METHODS

Retrospective cohort of 2137 adult patients, referred to tertiary hospital outpatient nephrologist between 2012 and 2020, were analysed. Referrals were analysed for concordance with the KHA referral guidelines and, with the KFRE score, a recommended practice.

RESULTS

Of 2137 patients, 626 (29%) did not have urine albumin-to-creatinine ratio (UACR) measurement at referral. For those who had a UACR, the number who met KFRE preferred referral criteria was 36% less than KHA criteria. If the recommended KFRE score was used, then fewer older patients (≥40 years) needed referral. Positively, many diabetes patients were referred, even if their risk of kidney failure was low, and 29% had a KFRE over 3%. For patients evaluated meeting KFRE criteria, a larger proportion (76%) remained in follow-up, with only 8% being discharged.

CONCLUSIONS

KFRE could reduce referrals and be a useful tool to assist timely referrals. Using KFRE for triage may allow those patients with very low risk of future kidney failure not be referred, remaining longer in primary care, saving health resources and reducing patients' stress and wait times. Using KFRE encourages albuminuria measurement.

An update on the global disparities in kidney disease burden and care across world countries and regions

BACKGROUND

Since 2015, the International Society of Nephrology (ISN) Global Kidney Health Atlas (ISN-GKHA) has spearheaded multinational efforts to understand the status and capacity of countries to provide optimal kidney care, particularly in low-resource settings. In this iteration of the ISN-GKHA, we sought to extend previous findings by assessing availability, accessibility, quality, and affordability of medicines, kidney replacement therapy (KRT), and conservative kidney management (CKM).

METHODS

A consistent approach was used to obtain country-level data on kidney care capacity during three phases of data collection in 2016, 2018, and 2022. The current report includes a detailed literature review of published reports, databases, and registries to obtain information on the burden of chronic kidney disease and estimate the incidence and prevalence of treated kidney failure. Findings were triangulated with data from a multinational survey of opinion leaders based on the WHO's building blocks for health systems (ie, health financing, service delivery, access to essential medicines and health technology, health information systems, workforce, and governance). Country-level data were stratified by the ISN geographical regions and World Bank income groups and reported as counts and percentages, with global, regional, and income level estimates presented as medians with interquartile ranges.

FINDINGS

The literature review used information on prevalence of chronic kidney disease from 161 countries. The global median prevalence of chronic kidney disease was 9·5% (IQR 5·9-11·7) with the highest prevalence in Eastern and Central Europe (12·8%, 11·9-14·1). For the survey analysis, responses received covered 167 (87%) of 191 countries, representing 97·4% (7·700 billion of 7·903 billion) of the world population. Chronic haemodialysis was available in 162 (98%) of 165 countries, chronic peritoneal dialysis in 130 (79%), and kidney transplantation in 116 (70%). However, 121 (74%) of 164 countries were able to provide KRT to more than 50% of people with kidney failure. Children did not have access to haemodialysis in 12 (19%) of 62 countries, peritoneal dialysis in three (6%) countries, or kidney transplantation in three (6%) countries. CKM (non-dialysis management of people with kidney failure chosen through shared decision making) was available in 87 (53%) of 165 countries. The annual median costs of KRT were: US$19 380 per person for haemodialysis, $18 959 for peritoneal dialysis, and $26 903 for the first year of kidney transplantation. Overall, 74 (45%) of 166 countries allocated public funding to provide free haemodialysis at the point of delivery; use of this funding scheme increased with country income level. The median global prevalence of nephrologists was 11·8 per million population (IQR 1·8-24·8) with an 80-fold difference between low-income and high-income countries. Differing degrees of health workforce shortages were reported across regions and country income levels. A quarter of countries had a national chronic kidney disease-specific strategy (41 [25%] of 162) and chronic kidney disease was recognised as a health priority in 78 (48%) of 162 countries.

INTERPRETATION

This study provides new information about the global burden of kidney disease and its treatment. Countries in low-resource settings have substantially diminished capacity for kidney care delivery. These findings have major policy implications for achieving equitable access to kidney care.

FUNDING

International Society of Nephrology.

Systematic review of externally validated machine learning models for predicting acute kidney injury in general hospital patients

Acute kidney injury (AKI) is one of the most common and consequential complications among hospitalized patients. Timely AKI risk prediction may allow simple interventions that can minimize or avoid the harm associated with its development. Given the multifactorial and complex etiology of AKI, machine learning (ML) models may be best placed to process the available health data to generate accurate and timely predictions. Accordingly, we searched the literature for externally validated ML models developed from general hospital populations using the current definition of AKI. Of 889 studies screened, only three were retrieved that fit these criteria. While most models performed well and had a sound methodological approach, the main concerns relate to their development and validation in populations with limited diversity, comparable digital ecosystems, use of a vast number of predictor variables and over-reliance on an easily accessible biomarker of kidney injury. These are potentially critical limitations to their applicability in diverse socioeconomic and cultural settings, prompting a need for simpler, more transportable prediction models which can offer a competitive advantage over the current tools used to predict and diagnose AKI.

Association of Country Income Level With the Characteristics and Outcomes of Critically Ill Patients Hospitalized With Acute Kidney Injury and COVID-19

Introduction

Acute kidney injury (AKI) has been identified as one of the most common and significant problems in hospitalized patients with COVID-19. However, studies examining the relationship between COVID-19 and AKI in low- and low-middle income countries (LLMIC) are lacking. Given that AKI is known to carry a higher mortality rate in these countries, it is important to understand differences in this population.

Methods

This prospective, observational study examines the AKI incidence and characteristics of 32,210 patients with COVID-19 from 49 countries across all income levels who were admitted to an intensive care unit during their hospital stay.

Results

Among patients with COVID-19 admitted to the intensive care unit, AKI incidence was highest in patients in LLMIC, followed by patients in upper-middle income countries (UMIC) and high-income countries (HIC) (53%, 38%, and 30%, respectively), whereas dialysis rates were lowest among patients with AKI from LLMIC and highest among those from HIC (27% vs. 45%). Patients with AKI in LLMIC had the largest proportion of community-acquired AKI (CA-AKI) and highest rate of in-hospital death (79% vs. 54% in HIC and 66% in UMIC). The association between AKI, being from LLMIC and in-hospital death persisted even after adjusting for disease severity.

Conclusions

AKI is a particularly devastating complication of COVID-19 among patients from poorer nations where the gaps in accessibility and quality of healthcare delivery have a major impact on patient outcomes.

Use of an extended KDIGO definition to diagnose acute kidney injury in patients with COVID-19: A multinational study using the ISARIC-WHO clinical characterisation protocol

BACKGROUND

Acute kidney injury (AKI) is one of the most common and significant problems in patients with Coronavirus Disease 2019 (COVID-19). However, little is known about the incidence and impact of AKI occurring in the community or early in the hospital admission. The traditional Kidney Disease Improving Global Outcomes (KDIGO) definition can fail to identify patients for whom hospitalisation coincides with recovery of AKI as manifested by a decrease in serum creatinine (sCr). We hypothesised that an extended KDIGO (eKDIGO) definition, adapted from the International Society of Nephrology (ISN) 0by25 studies, would identify more cases of AKI in patients with COVID-19 and that these may correspond to community-acquired AKI (CA-AKI) with similarly poor outcomes as previously reported in this population.

METHODS AND FINDINGS

All individuals recruited using the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC)-World Health Organization (WHO) Clinical Characterisation Protocol (CCP) and admitted to 1,609 hospitals in 54 countries with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection from February 15, 2020 to February 1, 2021 were included in the study. Data were collected and analysed for the duration of a patient's admission. Incidence, staging, and timing of AKI were evaluated using a traditional and eKDIGO definition, which incorporated a commensurate decrease in sCr. Patients within eKDIGO diagnosed with AKI by a decrease in sCr were labelled as deKDIGO. Clinical characteristics and outcomes-intensive care unit (ICU) admission, invasive mechanical ventilation, and in-hospital death-were compared for all 3 groups of patients. The relationship between eKDIGO AKI and in-hospital death was assessed using survival curves and logistic regression, adjusting for disease severity and AKI susceptibility. A total of 75,670 patients were included in the final analysis cohort. Median length of admission was 12 days (interquartile range [IQR] 7, 20). There were twice as many patients with AKI identified by eKDIGO than KDIGO (31.7% versus 16.8%). Those in the eKDIGO group had a greater proportion of stage 1 AKI (58% versus 36% in KDIGO patients). Peak AKI occurred early in the admission more frequently among eKDIGO than KDIGO patients. Compared to those without AKI, patients in the eKDIGO group had worse renal function on admission, more in-hospital complications, higher rates of ICU admission (54% versus 23%) invasive ventilation (45% versus 15%), and increased mortality (38% versus 19%). Patients in the eKDIGO group had a higher risk of in-hospital death than those without AKI (adjusted odds ratio: 1.78, 95% confidence interval: 1.71 to 1.80, p-value < 0.001). Mortality and rate of ICU admission were lower among deKDIGO than KDIGO patients (25% versus 50% death and 35% versus 70% ICU admission) but significantly higher when compared to patients with no AKI (25% versus 19% death and 35% versus 23% ICU admission) (all p-values <5 × 10-5). Limitations include ad hoc sCr sampling, exclusion of patients with less than two sCr measurements, and limited availability of sCr measurements prior to initiation of acute dialysis.

CONCLUSIONS

An extended KDIGO definition of AKI resulted in a significantly higher detection rate in this population. These additional cases of AKI occurred early in the hospital admission and were associated with worse outcomes compared to patients without AKI.

International Society of Nephrology Global Kidney Health Atlas: structures, organization, and services for the management of kidney failure in Latin America

Latin America is a region with a widely variable socioeconomic landscape, facing a surge in noncommunicable diseases, including chronic kidney disease and kidney failure, exposing significant limitations in the delivery of care. Despite region-wide efforts to explore and address these limitations, much uncertainty remains as to the capacity, accessibility, and quality of kidney failure care in Latin America. Through this second iteration of the International Society of Nephrology Global Kidney Health Atlas, we aimed to report on these indicators to provide a comprehensive map of kidney failure care in the region. Survey responses were received from 18 (64.2%) countries, representing 93.8% of the total population in Latin America. The median prevalence and incidence of treated kidney failure in Latin America were 715 and 157 per million population, respectively, the latter being higher than the global median (142 per million population), with Puerto Rico, Mexico, and El Salvador experiencing much of this growing burden. In most countries, public and private systems collectively funded most aspects of kidney replacement therapy (dialysis and transplantation) care, with patients incurring at least 1% to 25% of out-of-pocket costs. In most countries, >90% of dialysis patients able to access kidney replacement therapy received hemodialysis (n = 11; 5 high income and 6 upper-middle income), and only a small minority began with peritoneal dialysis (1%-10% in 67% of countries; n = 12). Few countries had chronic kidney disease registries or targeted detection programs. There is a large variability in the availability, accessibility, and quality of kidney failure care in Latin America, which appears to be subject to individual countries' funding structures, underreliance on cheap kidney replacement therapy, such as peritoneal dialysis, and limited chronic kidney disease surveillance and management initiatives.

Machine learning and chronic kidney disease risk prediction

With a prevalence of approximately 10–15% in Africa and a close relationship with other non-communicable diseases, chronic kidney disease (CKD) can result in a significant comorbidity burden and impact on quality of life. The complex spectrum of precipitants and drivers of progression present a challenge for early diagnosis and effective interventions. Predicting this progression can provide clinicians with guidance on the need and frequency of monitoring in specialist clinics, the degree to which interventions such as kidney biopsies and aggressive risk factor modification may be of use, and to plan, in a timely manner, the various elements of dialysis initiation and transplantation. For patients, such predictions have the potential to contextualise the recommended therapies and monitoring regimes prescribed, allowing them to engage better with decision making and planning if, and when, kidney replacement therapies are needed. This paper explores the use of machine learning to facilitate such predictions and improve our understanding of CKD as well as to provide a platform for future studies to examine their clinical utility and value to both clinicians and patients.

The Legal Doctrine of Informed Consent and Renal Dialysis - Do Patients Really Consent?

A doctor has a legal duty to secure the informed consent of a patient prior to performing a medical or surgical procedure. The elements of the legal doctrine of informed consent include capacity, voluntariness and the provision and understanding of relevant information. This article examines the doctrine in the context of renal dialysis. Dialysis is a complex therapy that impacts upon quality of life and has limited survival advantage in some patients. It is likely that informed consent is often not fully integrated into the care of patients commencing dialysis. The article analyses the common law doctrine of informed consent as it relates to dialysis and presents the findings of a retrospective study of the adequacy of the consent process based on interviews with dialysis patients who commenced dialysis in the previous 12 months. It concludes with recommendations for improvement in practice.

Role of endothelin-1 in the active constriction of human atherosclerotic coronary arteries

BACKGROUND

Atherosclerotic coronary arteries are prone to constriction but the underlying causes are incompletely understood. We tested the hypothesis that endothelin-1 (ET-1), a potent vasoconstrictor, contributes to the heightened tone of atherosclerotic human coronary arteries.

METHODS AND RESULTS

In 8 patients with coronary artery disease (CAD) and 8 patients with angiographically smooth coronary arteries (normal), we infused BQ-123, an antagonist of the ET(A) receptor, into a major coronary artery (infused artery) at 40 nmol/min for 60 minutes. The infused artery in the CAD patients contained a >50% stenosis. Using quantitative angiography, we compared the dilation of the infused artery with another, noninfused coronary artery. To estimate the magnitude of the contribution of ET-1 to coronary tone, we compared the dilation to BQ-123 with that elicited by intracoronary nitroglycerin (200 microgram). BQ-123 induced significant dilation in the normal arteries (7.3% at 60 minutes, P<0.001 versus noninfused arteries) and a greater dilation in the CAD arteries (16.3% at 60 minutes, P<0.001 versus infused normal arteries). The dilation at stenoses was particularly pronounced (21.6% at 60 minutes, P<0.001 versus infused CAD arteries). Compared with the dilation from nitroglycerin, ET-1 contributed to 39% of the coronary tone in normal arteries, 74% of tone in CAD arteries, and 106% of tone at stenoses (P<0.01).

CONCLUSIONS

ET-1 accounts for nearly all the resting tone in atherosclerotic coronary arteries, especially at stenoses. Inhibitors of ET-1, by relieving constriction, may significantly lessen the hemodynamic significance of coronary stenoses and thereby reduce myocardial ischemia.

Comparison of effects of suture materials on wound healing in a rabbit pyeloplasty model

OBJECTIVES

To compare the effects of chromic catgut, polyglactic acid, polydioxanone (PDS), and polytrimethylene carbonate suture on urothelial healing in a rabbit model simulating pyeloplasty.

METHODS

Pyeloureterotomies were performed on 8-week-old rabbits [12 rabbits (24 renal units) and 3 control rabbits] and closed with interrupted 7-0 sutures. At 10 days, 5 weeks, and 12 weeks postoperatively, we assessed the upper tracts by examining microscopic sections of the renal pelvis and upper ureter. Acute and chronic inflammation, foreign body reaction, and fibrosis/scar formation were assessed blindly and scored from 0 to 4.

RESULTS

Histologic evidence of acute and chronic inflammation and foreign body reaction was most severe at 10 days and 5 weeks in pyeloureterotomies closed with chromic catgut. There was mild inflammation in those closed with polyglactic acid at 10 days, but it was minimal in those closed with polyglactic acid, PDS, and polytrimethylene carbonate at 5 and 12 weeks. Reabsorption of polyglactic acid was complete by 5 weeks, but was incomplete with the other three sutures at that time. By 12 weeks, there was persistent suture in 50% of the renal units closed with polydioxanone and in 100% of those closed with polytrimethylene carbonate. No animal developed a renal calculus.

CONCLUSIONS

Because of the mild inflammatory response and rapid tissue reabsorption of polyglactic acid in this animal model, this suture appears to be the best suture for pyeloplasty.

[The pattern of the clinical use of digitalis. The need for a reassessment]

PURPOSE

To evaluate the pattern of utilization of digitalis in an academic hospital.

METHODS

Clinical files of all patients admitted in medical wards at the Hospital de Clínicas de Porto Alegre were studied. Data were collected during five different days, three in the winter and two in the summer, keeping an interval of at least two weeks between each data collection. Heart failure diagnosis was evaluated objectively by means of a score proposed by Carlson et al.

RESULTS

From a total number of 881 patients, 114 (13%) were receiving digoxin. Mean age was 66 +/- 13 years and 47% were males. Considering the patients who were taking digoxin, 32% presented scores compatible with definite or possible heart failure; 26% had atrial flutter or fibrillation; 18% had heart failure and supraventricular tachyarrhythmias; and in 24% no clear indications were found according to our criteria. Previous use of digoxin was found in 85% of the patients and 32% were withdrawn during the hospitalization. Considering just the patients who had no reason for using digoxin, only 44% had the drug withdrawn.

CONCLUSION

According to current criteria, many hospitalized patients receive digoxin without a definite indication. These data suggest that reassessment of the use of digitalis should be incorporated into clinical practice.

Lack of tolerance to imipramine or mianserine in two animal models of depression

Few clinical reports describe tolerance induced by antidepressants and this question is considered an unsolved problem for clinical use of this group of drugs. The present report deals with the effects of imipramine and mianserine on two animal models of depression, after acute or prolonged previous treatment with these antidepressants. Imipramine and mianserine potentiated amphetamine-induced anorexia both after acute administration or after prolonged previous treatment with each drug. Mianserine effects were not detected in the behavioral despair test and imipramine reduced rats immobility equally after acute and prolonged previous treatment. It was concluded that imipramine and mianserine do not induce detectable tolerance when previously administered to animals submitted to amphetamine anorexia or behavioral despair.