Abstract Background Chronic kidney disease (CKD) is common, associated with substantial comorbidity and strong socioeconomic gradients. Early CKD care focuses on preventing disease progression and reducing cardiovascular risk. However, inequities in access to CKD care are most pronounced early in the disease course, a critical window for equitable population-level prevention within primary care. Understanding how these inequities arise within primary care, where early identification and management largely occur, is therefore essential. This study explored how people living with CKD in deprived areas of Scotland, a setting characterised by marked health inequalities, establish candidacy for early kidney care at a point when prevention should begin but is often lacking. Methods A qualitative study informed by critical realism combined semi-structured interviews with 38 adults with CKD (predominantly Stage 3 and primarily managed in primary care) and focus groups or interviews with 23 primary care professionals ( N = 61). Participants were drawn from the most deprived 40% of neighbourhoods across three Scottish health boards, ensuring variation in CKD stage, diagnosis timing, professional role, and urban-rural setting. Data were analysed using reflexive thematic analysis informed by the Candidacy Framework. Results Early kidney care for working-age adults living in deprived areas is often delayed, with CKD detected when personal resources, including time, finances, and support, are already stretched. Diagnosis is typically explained briefly, if at all, leading to uncertainty about its significance and next steps. Communication and care vary widely, with many patients relying on personal persistence to navigate fragmented healthcare systems. Care frequently depends on professional discretion, with uneven community and voluntary resources bridging gaps in care. These patterns reflect structural constraints rather than individual disengagement. Conclusion Early kidney care in communities experiencing deprivation represents a constrained preventive window within primary care. The “triple invisibility” of early CKD, at population, system, and symptom levels, undermines sustained engagement at the point when intervention is most effective. Strengthening equitable prevention requires service-level redesign and workforce models that embed kidney health within routine cardiometabolic care, address structural constraints in deprived areas, and integrate physical and psychosocial risk management. Trial registration Not applicable.

INTRODUCTION:Previous randomized trials and real-world observational studies of electronic alerts for acute kidney injury (AKI) have yielded conflicting results. The applicability of trial findings to routine clinical practice is also contested. Despite this, AKI e-alerts remain widely implemented. Here, we used Regression Discontinuity Design (RDD) to evaluate the real-world causal effect of the nationwide AKI e-alert initiative in Wales. METHODS:The study encompassed hospital and community-based systems serving 3.1 million adults (aged 18 years and older) residing in Wales, 2016-2020, following implementation of AKI e-alerts across all Welsh health boards, seven using passive alerts and one using interruptive alerts. We assessed outcomes across the e-alert threshold, including mortality, hospital admission/readmission, AKI severity and recovery, documentation of AKI, prescribing, and follow-up monitoring of proteinuria and blood pressure. RESULTS:Among 861,494 hospital and 354,505 community patient encounters, AKI alerts were triggered in 5.8% and 2.0% of cases respectively (mean age 64 years, 54% female). In both settings, AKI alerts led to no significant changes in mortality [complier average treatment effect +1.31% (95% Confidence Interval -3.07, 4.74); +2.07% (-3.44, 6.65)] or admissions/readmissions [+0.13% (-3.82, 4.21); +4.07% (-1.84, 8.27)]. AKI coding was infrequent across both settings. Alerts modestly increased hospital coding [+5.88% (2.22, 7.58)] but had minimal impact on primary care coding post discharge [+0.72% (-0.67, 1.30)] and led to only small improvements in proteinuria and blood pressure monitoring. Findings were consistent across passive and interruptive alert types, clinical settings and subgroups. CONCLUSIONS:We found no causal evidence that AKI e-alerts (specifically implemented at a 50% creatinine rise threshold) improved or worsened clinical outcomes in this nationwide real-world evaluation. Consistently poor outcomes, limited documentation and follow-up care, even in the presence of e-alerts, underscore the need for an improved clinical response to AKI.

RATIONALE & OBJECTIVE:Many mortality risk prediction models for individuals with kidney failure are available; however, their development did not involve end-users during the design process, and none are widely used in clinical practice. We identified the needs and preferences of end-users to inform the development and enhance the usability of a mortality risk prediction tool for people with kidney failure. STUDY DESIGN:A half-day, online consensus workshop was conducted using a modified nominal group technique. SETTING & PARTICIPANTS:People with lived experience of kidney failure (patients with or without receipt of kidney replacement therapy and their caregivers) or kidney failure management (health care providers and policymakers) recruited from across Canada. ANALYTICAL APPROACH:Preferences were elicited in 3 topic areas: the tool's intended use, timing (prediction horizon and update frequency), and relevant predictor variables. Conventional content analysis of discussion transcripts was conducted to elaborate on the findings. RESULTS:Eighteen individuals from across 5 provinces participated in the workshop, including 7 patients, 3 caregivers, and 8 health care providers or policymakers. Participants prioritized the following: (1) tool use within clinics and in consultation with nephrologists; (2) personalization of the prediction time horizons and reassessment of risk prediction following changes in clinical condition; and (3) inclusion of coexisting conditions, kidney failure characteristics (eg, unplanned dialysis start), and frailty status as key predictor variables. Analysis of transcripts identified several factors influencing the tool's usability, including provider trust, comfort in discussing mortality risk, patient privacy, availability of follow-up and support systems, patient readiness, and feasibility of incorporating desired predictor variables. LIMITATIONS:Media-based recruitment and participation barriers may have limited the representativeness of the patient sample. CONCLUSIONS:End-users of mortality prediction tools for people with kidney failure prioritized design and use considerations. Co-design of future tools to align with end-user preferences may enhance their usability and enhance their uptake. PLAIN-LANGUAGE SUMMARY:Many calculators predict survival for people with kidney failure on dialysis, but few are used in practice, in part because they were not created with input from people who need them. To learn what users want, we conducted an online consensus workshop involving individuals living with kidney failure, caregivers, clinicians, and policymakers from across Canada. The participants discussed how and when the tool should be used and on which factors the tool should be based. They prioritized the use of the tool during clinic visits, personalizing the prediction horizon, and taking into account health conditions and frailty. The participants emphasized the importance of trust, comfort in communication, and support systems when using the tool. Involving users in tool design may enhance its usability and adoption.

Healthcare professionals should not label medications as ‘kidney toxins’ unless this is actually the case, especially medications that instead confer clear prognostic benefit, such as Renin-Angiotensin System inhibitors (RASi). This is imperative when discussing treatments with people with long-term health conditions, for whom RASi significantly reduce death, progression of chronic kidney disease (CKD) and hospitalisation.RASi are fundamental to management of heart failure with reduced ejection fraction (HFrEF) and CKD with proteinuria yet are frequently called ‘nephrotoxic’. The association between RASi use and acute kidney injury (AKI) is too often mistaken for ‘causation’; it is largely driven by the use of RASi to treat long-term conditions that increase AKI risk, such as HFrEF, CKD and diabetes mellitus.Mislabelling RASi as ‘nephrotoxic’ adversely affects vital decision making, driving a tendency for RASi avoidance, even when RASi use has clear prognostic benefit. Healthcare education must embed this clinically important change to convention.

Acute kidney injury (AKI) is a clinical syndrome characterised by a sudden deterioration of kidney function. It is common and usually occurs as a complication of severe illness or major surgery. Despite the high risk of complications and a decade of improvement initiatives in the UK, little is known about the quality of post-discharge AKI care. Our population-based cohort study investigated adherence to guideline-recommended post-AKI care in general practices in England. Using English hospital admission data (2017–2021), we created a cohort of discharged patients (≥ 18 years) with a hospital diagnostic code of AKI. Using linked Clinical Practice Research Datalink Aurum primary care data, we examined percentages of AKI episodes meeting the criteria of 14 guideline-recommended post-AKI care indicators, covering: AKI coding in primary care, post-discharge primary care contacts, kidney health and blood pressure monitoring, and guideline-indicated prescribing. Variations of indicator adherence according to patient characteristics were quantified using binomial mixed regression. 209,222 patients (48.0

Importance:Female individuals typically outlive male individuals in the general population. Whether this survival advantage persists among adults with stage 5 chronic kidney disease (CKD) is unknown. Objective:To examine sex differences in mortality and treatment with kidney replacement therapy (KRT; including dialysis and transplant) among adults with incident stage 5 CKD. Design, Setting, and Participants:This population-based cohort study used linked administrative and kidney care program data from Alberta, Canada. Adults 18 years and older with incident non-KRT-dependent stage 5 CKD were identified between April 2005 and March 2019 and observed from study entry until death, out-migration, or March 2021. Data were analyzed from January to August 2025. Main Outcomes and Measures:Sex-specific, age-stratified standardized mortality ratios were calculated using general population mortality data. Five-year probabilities of all-cause death, receipt of maintenance dialysis, and kidney transplant were estimated in incident stage 5 CKD cases using multistate models, stratified by age and presence of diabetes or cardiovascular disease. Results:Among 7506 cohort members, 4121 (54.9%) were male (median [IQR] age, 70 [58-80] years), and 3385 (45.1%) were female (median [IQR] age, 74 [61-83] years). The median (IQR) follow-up was 7.9 (4.7-11.5) years. Compared with the general population, female individuals experienced greater excess mortality than male individuals, particularly at younger ages (eg, among adults younger than 55 years: standardized mortality ratio, 40.9 [95% CI, 34.6-47.3] in female individuals vs 15.9 [95% CI, 13.5-18.2] in male individuals); this difference narrowed with increasing age. Within the stage 5 CKD cohort, 5-year all-cause mortality risks were higher in younger female individuals than male individuals (younger than 55 years: 20.7% vs 14.6%) and similar between sexes at older ages. Irrespective of comorbidity, female individuals younger than 65 years were substantially less likely to receive a kidney transplant, and female individuals 65 years and older were less likely to receive dialysis or a transplant. Conclusions and Relevance:In this cohort study using data from a universal health care system, across all ages, the female survival advantage observed in the general population was absent or even reversed after developing stage 5 CKD. Fewer female individuals transitioned to KRT treatment, independent of their comorbidities. Younger female individuals experienced the greatest survival disadvantage and were less likely to receive a transplant. These findings suggest that differences in treatment decision-making or inequities in access to KRT may contribute to poorer outcomes in female individuals, especially at younger ages. Further investigations are warranted to understand the potential underlying structural, social, and biological mechanisms.

Background:Patients hospitalized with acute kidney injury (AKI) have variable risks for chronic kidney disease (CKD); however, there is limited knowledge about how this risk influences outpatient follow-up with nephrologists. Objective:This survey study examined the likelihood that nephrologists would recommend outpatient follow-up of patients with varying risk profiles for CKD after hospitalization with AKI and the effect of reporting the predicted risk of severe CKD on their decision-making. Design:A randomized survey study examining the impact of providing predicted risks of severe CKD on nephrologists' follow-up recommendations for patients with AKI. Setting:The study included nephrologists from the United States, the United Kingdom, and Canada between September and December 2023. Patients:Participants reviewed clinical vignettes of patients with AKI and varying risks of severe CKD (G4 or G5), using an externally validated prediction model. Measurements:The primary outcome was the likelihood of recommending nephrologist specialist follow-up for each case, scored on a 7-point Likert scale (1 = "definitely not" and 7 = "definitely would"). Methods:Participants were randomized to receive a version of the survey either with or without the predicted risk of severe CKD included for each vignette. Responses were compared across categories of predicted risk (<10%, 10%-49%, and ≥50%) using generalized estimating equations. Results:Of the 203 nephrologists who participated, 73 (36%) were from the United Kingdom, 71 (35%) from Canada, and 45 (22%) from the United States. Mean (95% confidence interval [CI]) Likert scores increased from 4.01 (3.68, 4.34) for patients with a <10% predicted risk to 6.06 (5.76, 6.37) for those with a ≥ 50% predicted risk of severe CKD. Nephrologists were significantly less likely to recommend outpatient nephrology follow-up for patients with a <10% predicted risk of severe CKD when the risk was reported (mean difference = -0.71 [95% CI = -1.19, -0.23]), and significantly more likely to recommend follow-up for patients with a ≥50% predicted risk when the risk of severe CKD was reported (mean difference = 0.49 [95% CI = 0.04, 0.93]). Limitations:This study focuses on nephrologists from high-income countries and relies on hypothetical scenarios rather than real-world practices. Survey respondents may not be representative of all nephrologists, although consistent findings across diverse subgroups strengthen findings. Conclusions:When the predicted risk of severe CKD is reported, nephrologists are less likely to recommend follow-up for lower risk patients with AKI and more likely to recommend follow-up for higher risk patients, leading to better alignment of recommendations for outpatient follow-up with patient risk of severe CKD.

Despite a decade of initiatives in the UK to raise awareness of acute kidney injury (AKI) and isolated reports of progress through improvement work in some regions, concerns remain that people who have had AKI do not receive adequate follow-up and care after transitioning from hospital back into the community. People discharged from hospital after AKI often have complex health needs and multiple long-term conditions, are at high risk of multiple poor outcomes and have high rates of unplanned readmissions. There is therefore a need to examine factors that are associated with variations in post-discharge AKI care. As part of the AsterAKI study, a mixed methods study aiming to develop interventions to improve post-discharge AKI care in primary care, we performed a cohort study to describe variations in the implementation of recommended post-discharge AKI care. Using admission data in England from Hospital Episode Statistics, we delineated a cohort of adult patients (≥18 years) with a hospital diagnostic code of AKI discharged between 1 January 2017 and 31 March 2021. Using linked primary care data from the Clinical Practice Research Datalink Aurum, we measured adherence to indicators of good care covering domains of (1) recording of AKI in primary care, (2) timeliness of post-discharge clinical reviews, (3) recommendations to monitoring of recovery at 90 days, and (4) guideline indicated prescribing. We evaluated care quality both overall, and within subgroups based on demographic, socioeconomic, and clinical characteristics. A total of 209,222 patients (48.0% females; mean age 74.1 years, SD 15.6) were included in the study cohort, representing 279,187 AKI hospital inpatient episodes. While some form of clinical contact (either in person or remotely) was made within 30 days of discharge for 72.5% of episodes, only 19.5% had a diagnosis of AKI hospitalisation recorded in the primary care notes. These percentages rose to 88.1% and 22.0% respectively at 90 days. Variations by demographic and socioeconomic factors were observed. At around 90 days post-discharge, measurement of serum creatinine for kidney recovery occurred in 34.2% of episodes, blood pressure was recorded in 34.6%, and urine albuminuria testing in only 3.8%. Of people with a guideline indication for a renin-angiotensin system inhibitor (RAASi) based on diabetes/hypertension and proteinuria levels, only 42.1% received a prescription. Across all subgroups of people with a hospital diagnostic code of AKI in this analysis, AKI was rarely documented in the patient's primary care records, and only a minority received the recommended post-AKI monitoring of blood and urine testing or blood pressure measurement, despite relatively high levels of contact with health care professionals. Rates of measuring albuminuria were particularly low, despite its strong association with subsequent kidney and cardiovascular events. Further, rates of prescribing of RAASi were low in patients who could benefit from these medications. Recommendations to improve this include provision of clear, case-specific guidance on post-discharge management to primary care professionals, and development of concerted implementation strategies between secondary and primary care.

Background:Existing population research has evaluated inequities in health outcomes for people in deprived communities who have early kidney disease, but not the differences in their self-reported overall health and ability to manage daily life activities when they first present, or the additional burden for people of working age. Using their responses to the national Census in Scotland, we studied the self-reported overall health and impact on day-to-day life of people in deprived and affluent households who newly presented with evidence of kidney disease. Methods:Of 458 897 adult North Scotland residents, we included all 24 775 individuals who presented with new onset kidney disease (eGFR <60 ml/min/1.72 m2) in 2011-2014. We measured deprivation based on household (Census) and resident neighbourhood (index of multiple deprivation). We fitted proportional odds regression models that accounted for age, sex, comorbidities, and additional impairments (e.g. vision, hearing, learning difficulties). We further adjusted for self-reported mental health and living alone as potential mediators, and tested for interactions with working age (18-65 years), sex, and mental health. Results:Of 24 775 people newly presenting with kidney disease, already 11 115 (45%) reported limitations in their daily lives. People in the most deprived (vs least) neighbourhoods and households experienced 2-fold greater odds of worse self-reported health (adjusted odds ratio, OR 2.05, 1.81-2.32 neighbourhood; OR 1.93, 1.64-2.26 household); and greater limitation in day-to-day activities (OR 1.70, 1.49-1.95 neighbourhood; OR 1.65, 1.39-1.96 household). This pattern of inequity was even more pronounced (3-fold) among those of working age (interaction P < .0001). Conclusion:The association of deprivation with health and daily life represents an additional dimension of health inequity that is substantial, and evident from the earliest stages for people with kidney disease.

Acute kidney injury (AKI) is common after major surgery and is associated with increased mortality. Currently, the Kidney Disease: Improving Global Outcomes (KDIGO) criteria define AKI as an absolute creatinine increase ≥0.3 mg/dl within 48 hours, a relative creatinine increase ≥50% known or presumed to have occurred within 7 days, or a urine output <0.5 ml/kg/h for at least 6 hours. However, it remains contested whether small absolute creatinine increases should be viewed as equivalent to relative creatinine increases—especially for low baseline estimated glomerular filtration rate (eGFR) where such creatinine changes relate to smaller eGFR changes. Here, we used a multinational collaboration to investigate this uncertainty. We conducted a multinational population-based cohort study including adult patients from Denmark, Alberta (Canada), Grampian, and Tayside & Fife (United Kingdom) undergoing major elective surgery. The inclusion of patients undergoing major elective surgery allowed for accurate assessment of baseline eGFR and postoperative changes in creatinine. This is because it is standard practice in all the included cohorts to have a recent outpatient creatinine measurement before surgery and to monitor creatinine levels in the days following surgery. We ascertained the most recent outpatient eGFR before surgery using the 2009 creatinine-based Chronic Kidney Disease Epidemiology Collaboration equation. We determined both the highest relative increase in creatinine within 7 days and the highest absolute increase in creatinine within 2 days during the first 7 days after the day of surgery. The outcome of interest was death within 90 days after surgery. Logistic regressions were performed to construct heatmaps depicting age-, sex-, year-, and surgery type-standardized 90-day mortality according to absolute and relative creatinine increases across pre-operative baseline eGFR levels. We identified 314,136 surgical procedures (172,544 procedures from Denmark, 124,119 from Alberta, 9891 from Grampian, and 7582 from Tayside & Fife) performed in 276,988 patients with 13,906 deaths within 90 days. Across the populations, the median age ranged from 66 to 70 years, and 40 to 44% were female. Absolute creatinine increases: Compared to no change in creatinine, an absolute increase of 0.3 mg/dl (26.5 µmol/l) within 2 days was associated with a consistent 2.5–3.5 percentage point (%p) absolute increase in mortality for eGFR between 15 and 90 ml/min/1.73 m2 (Figs 1 and 2). The increase in mortality was >3.5%p at eGFR >90 mL/min/1.73 m² and <2.5%p at eGFR <15 mL/min/1.73 m², although the precision of these estimates was low. These absolute increases in mortality corresponded to a relative increase in mortality of 25% for a baseline eGFR of 15 ml/min/1.73 m2, 160% for a baseline eGFR of 90 ml/min/1.73 m2, and 244% for an eGFR of 120 ml/min/1.73 m2. Relative creatinine increases: The absolute increases in mortality between a 50% relative creatinine increase and no change within 7 days decreased with eGFR from 9.6%p for a baseline eGFR of 15 ml/min/1.73 m2 to 3.5%p for a baseline eGFR of 90 ml/min/1.73 m2 (Figs 1 and 2). After this point, it increased to 5.3%p for a baseline eGFR of 120 ml/min/1.73 m2. The corresponding relative increases in mortality rose from 134% for a baseline eGFR of 15 ml/min/1.73 m2 to 255% for a baseline eGFR of 60 ml/min/1.73 m2, after which it remained at the same level. Across baseline eGFR levels >15 ml/min/1.73 m2, both an absolute creatinine increase of 0.3 mg/dl and a relative increase of 50% were associated with a considerably higher mortality than no change. Yet, the magnitude of the increase in risk was substantially higher for a 50% increase compared with a 0.3 mg/dl increase at low baseline eGFR. This distinction should be emphasized in future guidelines to improve the consistency of clinical interpretations.

Importance:People with kidney failure have a high risk of death and poor quality of life. Mortality risk prediction models may help them decide which form of treatment they prefer. Objective:To systematically review the quality of existing mortality prediction models for people with kidney failure and assess whether they can be applied in clinical practice. Evidence Review:MEDLINE, Embase, and the Cochrane Library were searched for studies published between January 1, 2004, and September 30, 2024. Studies were included if they created or evaluated mortality prediction models for people who developed kidney failure, whether treated or not treated with kidney replacement with hemodialysis or peritoneal dialysis. Studies including exclusively kidney transplant recipients were excluded. Two reviewers independently extracted data and graded each study at low, high, or unclear risk of bias and applicability using recommended checklists and tools. Reviewers used the Prediction Model Risk of Bias Assessment Tool and followed prespecified questions about study design, prediction framework, modeling algorithm, performance evaluation, and model deployment. Analyses were completed between January and October 2024. Findings:A total of 7184 unique abstracts were screened for eligibility. Of these, 77 were selected for full-text review, and 50 studies that created all-cause mortality prediction models were included, with 2 963 157 total participants, who had a median (range) age of 64 (52-81) years. Studies had a median (range) proportion of women of 42% (2%-54%). Included studies were at high risk of bias due to inadequate selection of study population (27 studies [54%]), shortcomings in methods of measurement of predictors (15 [30%]) and outcome (12 [24%]), and flaws in the analysis strategy (50 [100%]). Concerns for applicability were also high, as study participants (31 [62%]), predictors (17 [34%]), and outcome (5 [10%]) did not fit the intended target clinical setting. One study (2%) reported decision curve analysis, and 15 (30%) included a tool to enhance model usability. Conclusions and Relevance:According to this systematic review of 50 studies, published mortality prediction models were at high risk of bias and had applicability concerns for clinical practice. New mortality prediction models are needed to inform treatment decisions in people with kidney failure.

INTRODUCTION:Guidelines define kidney failure based on initiation of maintenance kidney replacement therapy (KRT) or estimated glomerular filtration rate (eGFR) below 15 ml/min per 1.73 m2 for over 90 days, but most kidney failure registries track the incidence and outcomes of people who receive KRT only. The population burden of kidney failure and outcomes of patients identified by eGFR criteria remain understudied. METHODS:Using population-based datasets from Alberta, Canada, we studied adults who initiated KRT or had incident kidney failure defined by KRT or eGFR criteria between April 2008 and March 2019. Individuals who met eGFR criteria for kidney failure were followed from cohort entry until death, initiation of KRT, or censoring (outmigration or March 31, 2021) to estimate the five-year risks of KRT initiation and death without receiving KRT and the rates of acute care utilization during follow-up. RESULTS:The annual incidence was 212 per million population for KRT versus 293 for kidney failure, with larger incidence differences between KRT and kidney failure in older age and females. Among the 9691 incident kidney failure cases, 6216 (64.1%) were first identified by eGFR criteria. Within five years of meeting eGFR criteria, 34.0% died without receiving KRT. Females were less likely to receive KRT, more likely to die without receiving KRT, and had higher acute care use. CONCLUSIONS:KRT registries may capture only one-third of incident kidney failure cases, inaccurately record the timing of disease onset, and under-represent older adults and females who have worse outcomes. Incorporating eGFR measurements to expand kidney failure data collection initiatives can potentially improve early disease identification, equity of healthcare planning, and outcome reporting for all affected individuals.

In the current paper, we will focus on requirements to ensure big data can advance the outcomes of our patients suffering from kidney disease. The associated ethical question is whether and how we as a nephrology community can and should encourage the collection of big data of our patients. We identify some ethical reflections on the use of big data, and their importance and relevance. Furthermore, we balance advantages and pitfalls and discuss requirements to make legitimate and ethical use of big data possible.  The collection, organization, and curation of data come upfront in the pipeline before any analyses. Great care must therefore be taken to ensure quality of the data at this stage, to avoid the 'garbage in garbage out' problem and suboptimal patient care as a consequence of such analyses.  Access to the data should be organized so that correct and efficient use of data is possible. This means that data must be stored safely, so that only those entitled to do so can access them. At the same time, those who are entitled to access the data should be able to do so in an efficient way, so as not to hinder relevant research.  Analysis of observational data is itself prone to many errors and biases. Each of these biases can finally result in provision of low-quality medical care. Secure platforms should therefore also ensure correct methodology is used to interpret the available data. This requires close collaboration of a skilled workforce of experts in medical research and data scientists. Only then will our patients be able to benefit fully from the potential of AI and big data.