Using the kidney failure risk equation to predict end-stage kidney disease in CKD patients of South Asian ethnicity: an external validation study.

BACKGROUND: The kidney failure risk equation (KFRE) predicts the 2- and 5-year risk of needing kidney replacement therapy (KRT) using four risk factors - age, sex, urine albumin-to-creatinine ratio (ACR) and creatinine-based estimated glomerular filtration rate (eGFR). Although the KFRE has been recalibrated in a UK cohort, this did not consider minority ethnic groups. Further validation of the KFRE in different ethnicities is a research priority. The KFRE also does not consider the competing risk of death, which may lead to overestimation of KRT risk. This study externally validates the KFRE for patients of South Asian ethnicity and compares methods for accounting for ethnicity and the competing event of death. METHODS: Data were gathered from an established UK cohort containing 35,539 individuals diagnosed with chronic kidney disease. The KFRE was externally validated and updated in several ways taking into account ethnicity, using recognised methods for time-to-event data, including the competing risk of death. A clinical impact assessment compared the updated models through consideration of referrals made to secondary care. RESULTS: The external validation showed the risk of KRT differed by ethnicity. Model validation performance improved when incorporating ethnicity and its interactions with ACR and eGFR as additional risk factors. Furthermore, accounting for the competing risk of death improved prediction. Using criteria of 5 years ≥ 5% predicted KRT risk, the competing risks model resulted in an extra 3 unnecessary referrals (0.59% increase) but identified an extra 1 KRT case (1.92% decrease) compared to the previous best model. Hybrid criteria of predicted risk using the competing risks model and ACR ≥ 70 mg/mmol should be used in referrals to secondary care. CONCLUSIONS: The accuracy of KFRE prediction improves when updated to consider South Asian ethnicity and to account for the competing risk of death. This may reduce unnecessary referrals whilst identifying risks of KRT and could further individualise the KFRE and improve its clinical utility. Further research should consider other ethnicities.

Epidemiology of childhood acute kidney injury in England using e-alerts.

Background: Few studies describe the epidemiology of childhood acute kidney injury (AKI) nationally. Laboratories in England are required to issue electronic (e-)alerts for AKI based on serum creatinine changes. This study describes a national cohort of children who received an AKI alert and their clinical course. Methods: A cross-section of AKI episodes from 2017 are described. Hospital record linkage enabled description of AKI-associated hospitalizations including length of stay (LOS) and critical care requirement. Risk associations with critical care (hospitalized cohort) and 30-day mortality (total cohort) were examined using multivariable logistic regression. Results: In 2017, 7788 children (52% male, median age 4.4 years, interquartile range 0.9-11.5 years) experienced 8927 AKI episodes; 8% occurred during birth admissions. Of 5582 children with hospitalized AKI, 25% required critical care. In children experiencing an AKI episode unrelated to their birth admission, Asian ethnicity, young (<1 year) or old (16-<18 years) age (reference 1-<5 years), and high peak AKI stage had higher odds of critical care. LOS was higher with peak AKI stage, irrespective of critical care admission. Overall, 30-day mortality rate was 3% (n = 251); youngest and oldest age groups, hospital-acquired AKI, higher peak stage and critical care requirement had higher odds of death. For children experiencing AKI alerts during their birth admission, no association was seen between higher peak AKI stage and critical care admission. Conclusions: Risk associations for adverse AKI outcomes differed among children according to AKI type and whether hospitalization was related to birth. Understanding the factors driving AKI development and progression may help inform interventions to minimize morbidity.

Seasonal mortality trends for hospitalised patients with acute kidney injury across England.

BACKGROUND: Incidence of acute kidney injury (AKI) is known to peak in winter months. This is likely influenced by seasonality of commonly associated acute illnesses. We set out to assess seasonal mortality trends for patients who develop AKI across the English National Health Service (NHS) and to better understand associations with patient 'case-mix'. METHODS: The study cohort included all hospitalised adult patients in England who triggered a biochemical AKI alert in 2017. We modelled the impact of season on 30-day mortality using multivariable logistic regression; adjusting for age, sex, ethnicity, index of multiple deprivation (IMD), primary diagnosis, comorbidity (RCCI), elective/emergency admission, peak AKI stage and community/hospital acquired AKI. Seasonal odds ratios for AKI mortality were then calculated and compared across individual NHS hospital trusts. RESULTS: The crude 30-day mortality for hospitalised AKI patients was 33% higher in winter compared to summer. Case-mix adjustment for a wide range of clinical and demographic factors did not fully explain excess winter mortality. The adjusted odds ratio of patients dying in winter vs. summer was 1.25 (1.22-1.29), this was higher than for Autumn and Spring vs. Summer, 1.09 (1.06-1.12) and 1.07 (1.04-1.11) respectively and varied across different NHS trusts (9 out of 90 centres outliers). CONCLUSION: We have demonstrated an excess winter mortality risk for hospitalised patients with AKI across the English NHS, which could not be fully explained by seasonal variation in patient case-mix. Whilst the explanation for worse winter outcomes is not clear, unaccounted differences including 'winter-pressures' merit further investigation.

National recommendations to standardise acute kidney injury detection and alerting.

BACKGROUND: National Health Service England issued a Patient Safety Alert in 2014 mandating all acute Trusts in England to implement Acute Kidney Injury (AKI) warning stage results and to do so using a standardised algorithm. In 2021, the Renal and Pathology Getting It Right First Time (GIRFT) teams found significant variation in AKI reporting across the UK. A survey was designed to capture information on the entire AKI detection and alerting process to investigate the potential sources of this unwarranted variation. METHODS: In August 2021, an online survey consisting of 54 questions was made available to all UK laboratories. The questions covered creatinine assays, laboratory information management systems (LIMS), the AKI algorithm and AKI reporting. RESULTS: We received 101 responses from laboratories. Data were reviewed for England only - 91 laboratories. Findings included that 72% used enzymatic creatinine. In addition, 7 manufacturer-analytical platforms, 15 different LIMS and a wide range of creatinine reference ranges were in use. In 68% of laboratories, the AKI algorithm was installed by the LIMS provider. Marked variation was found in the minimum age of AKI reporting with only 18% starting at the recommended 1 month/28-days. Some 89% phoned all new AKI2s and AKI3s, as per AKI guidance while 76% provided comments/hyperlinks in reports. CONCLUSIONS: The national survey has identified laboratory practices that potentially contribute to unwarranted variation in the reporting of AKI in the England. This has formed the basis for improvement work to remedy the situation, including national recommendations, included within this article.

What data collection methods work best for COVID19 outbreak surveillance for people with end stage kidney disease? An observational cohort study using the UK Renal Registry.

BACKGROUND: Patients on kidney replacement therapy (KRT) are vulnerable to severe illness from COVID-19. Timely, accurate surveillance is essential for planning and implementing infection control at local, regional and national levels. Our aim was to compare two methods of data collection for COVID-19 infections amongst KRT patients in England. METHODS: Adults receiving KRT in England were linked to two sources of data on positive COVID-19 tests recorded March-August 2020: (1) submissions from renal centres to the UK Renal Registry (UKRR) and (2) Public Health England (PHE) laboratory data. Patient characteristics, cumulative incidence by modality (in-centre haemodialysis (ICHD), home HD, peritoneal dialysis (PD) and transplant), and 28-day survival were compared between the two sources. RESULTS: 2,783/54,795 patients (5.1%) had a positive test in the combined UKRR-PHE dataset. Of these 2,783, 87% had positive tests in both datasets. Capture was consistently high for PHE (> 95% across modalities) but varied for UKRR (ranging from ICHD 95% to transplant 78%, p < 0.0001). Patients captured only by PHE were more likely to be on transplant or home therapies (OR 3.5 95% CI [2.3-5.2] vs. ICHD) and to be infected in later months (OR 3.3 95%CI [2.4-4.6] for May-June, OR 6.5 95%CI [3.8-11.3] for July-August, vs. March-April), compared to patients in both datasets. Stratified by modality, patient characteristics and 28-day survival were similar between datasets. CONCLUSIONS: For patients undergoing ICHD treatment the collection of data submitted directly by renal centres allows constant monitoring in real time. For other KRT modalities, using a national swab test dataset through frequent linkage may be the most effective method. Optimising central surveillance can improve patient care by informing interventions and assisting planning at local, regional and national levels.

The Kidney Failure Risk Equation: Evaluation of Novel Input Variables including eGFR Estimated Using the CKD-EPI 2021 Equation in 59 Cohorts.

SIGNIFICANCE STATEMENT: The kidney failure risk equation (KFRE) uses age, sex, GFR, and urine albumin-to-creatinine ratio (ACR) to predict 2- and 5-year risk of kidney failure in populations with eGFR <60 ml/min per 1.73 m 2 . However, the CKD-EPI 2021 creatinine equation for eGFR is now recommended for use but has not been fully tested in the context of KFRE. In 59 cohorts comprising 312,424 patients with CKD, the authors assessed the predictive performance and calibration associated with the use of the CKD-EPI 2021 equation and whether additional variables and accounting for the competing risk of death improves the KFRE's performance. The KFRE generally performed well using the CKD-EPI 2021 eGFR in populations with eGFR <45 ml/min per 1.73 m 2 and was not improved by adding the 2-year prior eGFR slope and cardiovascular comorbidities. BACKGROUND: The kidney failure risk equation (KFRE) uses age, sex, GFR, and urine albumin-to-creatinine ratio (ACR) to predict kidney failure risk in people with GFR <60 ml/min per 1.73 m 2 . METHODS: Using 59 cohorts with 312,424 patients with CKD, we tested several modifications to the KFRE for their potential to improve the KFRE: using the CKD-EPI 2021 creatinine equation for eGFR, substituting 1-year average ACR for single-measure ACR and 1-year average eGFR in participants with high eGFR variability, and adding 2-year prior eGFR slope and cardiovascular comorbidities. We also assessed calibration of the KFRE in subgroups of eGFR and age before and after accounting for the competing risk of death. RESULTS: The KFRE remained accurate and well calibrated overall using the CKD-EPI 2021 eGFR equation. The other modifications did not improve KFRE performance. In subgroups of eGFR 45-59 ml/min per 1.73 m 2 and in older adults using the 5-year time horizon, the KFRE demonstrated systematic underprediction and overprediction, respectively. We developed and tested a new model with a spline term in eGFR and incorporating the competing risk of mortality, resulting in more accurate calibration in those specific subgroups but not overall. CONCLUSIONS: The original KFRE is generally accurate for eGFR <45 ml/min per 1.73 m 2 when using the CKD-EPI 2021 equation. Incorporating competing risk methodology and splines for eGFR may improve calibration in low-risk settings with longer time horizons. Including historical averages, eGFR slopes, or a competing risk design did not meaningfully alter KFRE performance in most circumstances.

NEPHwork: creating a quality improvement and research network for UK renal trainees.

NEPHwork was established in 2020 as a renal specialty trainee-driven national quality improvement and research network with the aim of coupling the benefits of trainee-led collaboration with the rich data collection infrastructure established by the UK renal registry. NEPHwork was established to support the development, coordination and delivery of audit and research projects by renal trainees on a national scale. The first collaborative project centred on the compliance with care quality standards in managing acute kidney injury. The project enabled a large amount of data to be collected over a relatively short period of time and allowed comparison between renal units involved in contributing to the data. The initiation of the NEPHwork collaboration had to overcome delays and service pressure related to the COVID-19 pandemic. Furthermore, the method of linkage analysis used in the data collection and lack of cohesion with regional information technology (IT) services prevented trainees from certain regions from contributing to the project and this is a key priority for the next NEPHwork collaboration.

Development and Validation of Prediction Models of Adverse Kidney Outcomes in the Population With and Without Diabetes.

OBJECTIVE: To predict adverse kidney outcomes for use in optimizing medical management and clinical trial design. RESEARCH DESIGN AND METHODS: In this meta-analysis of individual participant data, 43 cohorts (N = 1,621,817) from research studies, electronic medical records, and clinical trials with global representation were separated into development and validation cohorts. Models were developed and validated within strata of diabetes mellitus (presence or absence) and estimated glomerular filtration rate (eGFR; ≥60 or <60 mL/min/1.73 m2) to predict a composite of ≥40% decline in eGFR or kidney failure (i.e., receipt of kidney replacement therapy) over 2-3 years. RESULTS: There were 17,399 and 24,591 events in development and validation cohorts, respectively. Models predicting ≥40% eGFR decline or kidney failure incorporated age, sex, eGFR, albuminuria, systolic blood pressure, antihypertensive medication use, history of heart failure, coronary heart disease, atrial fibrillation, smoking status, and BMI, and, in those with diabetes, hemoglobin A1c, insulin use, and oral diabetes medication use. The median C-statistic was 0.774 (interquartile range [IQR] = 0.753, 0.782) in the diabetes and higher-eGFR validation cohorts; 0.769 (IQR = 0.758, 0.808) in the diabetes and lower-eGFR validation cohorts; 0.740 (IQR = 0.717, 0.763) in the no diabetes and higher-eGFR validation cohorts; and 0.750 (IQR = 0.731, 0.785) in the no diabetes and lower-eGFR validation cohorts. Incorporating the previous 2-year eGFR slope minimally improved model performance, and then only in the higher-eGFR cohorts. CONCLUSIONS: Novel prediction equations for a decline of ≥40% in eGFR can be applied successfully for use in the general population in persons with and without diabetes with higher or lower eGFR.

Advanced chronic kidney disease among UK children.

The UK Renal Registry currently collects information on UK children with kidney failure requiring long-term kidney replacement therapy (KRT), which supports disease surveillance and auditing of care and outcomes; however, data are limited on children with chronic kidney disease (CKD) not on KRT. METHODS: In March 2020, all UK Paediatric Nephrology centres submitted data on children aged <16 years with severely reduced kidney function as of December 2019, defined as an estimated glomerular filtration rate <30 mL/min/1.73 m2. RESULTS: In total, 1031 children had severe CKD, the majority of whom (80.7%) were on KRT. The overall prevalence was 81.2 (95% CI 76.3 to 86.3) per million of the age-related population. CONCLUSIONS: The prevalence of severe CKD among UK children is largely due to a high proportion of children on long-term KRT. Expanding data capture to include children with CKD before reaching failure will provide greater understanding of the CKD burden in childhood.

Risk factors associated with COVID-19 severity among patients on maintenance haemodialysis: a retrospective multicentre cross-sectional study in the UK.

OBJECTIVES: To assess the applicability of risk factors for severe COVID-19 defined in the general population for patients on haemodialysis. SETTING: A retrospective cross-sectional study performed across thirty four haemodialysis units in midlands of the UK. PARTICIPANTS: All 274 patients on maintenance haemodialysis who tested positive for SARS-CoV-2 on PCR testing between March and August 2020, in participating haemodialysis centres. EXPOSURE: The utility of obesity, diabetes status, ethnicity, Charlson Comorbidity Index (CCI) and socioeconomic deprivation scores were investigated as risk factors for severe COVID-19. MAIN OUTCOMES AND MEASURES: Severe COVID-19, defined as requiring supplemental oxygen or respiratory support, or a C reactive protein of ≥75 mg/dL (RECOVERY trial definitions), and its association with obesity, diabetes status, ethnicity, CCI, and socioeconomic deprivation. RESULTS: 63.5% (174/274 patients) developed severe disease. Socioeconomic deprivation associated with severity, being most pronounced between the most and least deprived quartiles (OR 2.81, 95% CI 1.22 to 6.47, p=0.015), after adjusting for age, sex and ethnicity. There was no association between obesity, diabetes status, ethnicity or CCI with COVID-19 severity. We found no evidence of temporal evolution of cases (p=0.209) or clustering that would impact our findings. CONCLUSION: The incidence of severe COVID-19 is high among patients on haemodialysis; this cohort should be considered high risk. There was strong evidence of an association between socioeconomic deprivation and COVID-19 severity. Other risk factors that apply to the general population may not apply to this cohort.

Comparison of Outcomes of In-Centre Haemodialysis Patients between the 1st and 2nd COVID-19 Outbreak in England, Wales, and Northern Ireland: A UK Renal Registry Analysis.

INTRODUCTION: This retrospective cohort study compares in-centre haemodialysis (ICHD) patients' outcomes between the 1st and 2nd waves of the COVID-19 pandemic in England, Wales, and Northern Ireland. METHODS: All people aged ≥18 years receiving ICHD at 31 December 2019, who were still alive and not in receipt of a kidney transplant at 1 March and who had a positive polymerase chain reaction test for SARS-CoV-2 between 1 March 2020 and 31 January 2021, were included. The COVID-19 infections were split into two "waves": wave 1 from March to August 2020 and wave 2 from September 2020 to January 2021. Cumulative incidence of COVID-19, multivariable Cox models for risk of positivity, median, and 95% credible interval of reproduction number in dialysis units were calculated separately for wave 1 and wave 2. Survival and hazard ratios for mortality were described with age- and sex-adjusted Kaplan-Meier plots and multivariable Cox proportional models. RESULTS: 4,408 ICHD patients had COVID-19 during the study period. Unadjusted survival at 28 days was similar in both waves (wave 1 75.6% [95% confidence interval [CI]: 73.7-77.5], wave 2 76.3% [95% CI 74.3-78.2]), but death occurred more rapidly after detected infection in wave 1. Long vintage treatment and not being on the transplant waiting list were associated with higher mortality in both waves. CONCLUSIONS: Risk of death of patients on ICHD treatment with COVID-19 remained unchanged between the first and second outbreaks. This highlights that this vulnerable patient group needs to be prioritized for interventions to prevent severe COVID-19, including vaccination, and the implementation of measures to reduce the risk of transmission alone is not sufficient.

Burnout and long COVID among the UK nephrology workforce: results from a national survey investigating the impact of COVID-19 on working lives.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is placing a significant strain on healthcare. We conducted a national survey of the UK nephrology workforce to understand its impacts on their working lives. METHODS: An online questionnaire incorporating the Maslach Burnout Inventory score was distributed between 31 March and 1 May 2021, with a focus on COVID-19 and long COVID incidence, vaccine uptake, burnout and working patterns. Data were analysed qualitatively and quantitatively; multivariable logistic regression was used to identify associations. RESULTS: A total of 423 responses were received. Of them, 29% had contracted COVID-19, which was more common among doctors and nurses {odds ratio [OR] 2.18 [95% confidence interval (CI) 1.13-4.22]} and those <55 years of age [OR 2.60 (95% CI 1.38-4.90)]. Of those who contracted COVID-19, 36% had symptoms of long COVID, which was more common among ethnicities other than White British [OR 2.57 (95% CI 1.09-6.05)]. A total of 57% had evidence of burnout, which was more common among younger respondents [OR 1.92 (95% CI 1.10-3.35)] and those with long COVID [OR 10.31 (95% CI 1.32-80.70)], and 59% with reconfigured job plans continued to work more hours. More of those working full-time wished to retire early. A total of 59% experienced remote working, with a majority preference for continuing this in the future. In terms of vaccination, 95% had received one dose of a COVID-19 vaccine and 86% had received two doses by May 2021. CONCLUSIONS: Burnout and long COVID is prevalent with impacts on working lives. Some groups are more at risk. Vaccination uptake is high and remote and flexible working were well received. Institutional interventions are needed to prevent workforce attrition.

Centre variation in mortality following post-hospitalization acute kidney injury: analysis of a large national cohort.

BACKGROUND: Routine monitoring of outcomes for patients with acute kidney injury (AKI) is important to drive ongoing quality improvement in patient care. In this study we describe the development of a case mix-adjusted 30-day mortality indicator for patients with post-hospitalization AKI (PH-AKI) across England to facilitate identification of any unwarranted centre variation in outcomes. METHODS: We utilized a routinely collected national dataset of biochemically detected AKI cases linked with national hospitals administrative and mortality data. A total of 250 504 PH-AKI episodes were studied across 103 National Health Service hospital trusts between January 2017 and December 2018. Standardized mortality ratios (SMRs) were calculated for each trust using logistic regression, adjusting for age, sex, primary diagnosis, comorbidity score, AKI severity, month of AKI and admission method. RESULTS: The mean 30-day mortality rate was high, at 28.6%. SMRs for 23/103 trusts were classed as outliers, 12 above and 11 below the 95% confidence limits. Patients with PH-AKI had mortality rates >5 times higher than the overall hospitalized population in 90/136 diagnosis groups and >10 times higher in 60/136 groups. Presentation at trusts with a co-located specialist nephrology service was associated with a lower mortality risk, as was South Asian or Black ethnicity. Deprivation, however, was associated with higher mortality. CONCLUSIONS: This is the largest multicentre analysis of mortality for patients with biochemically ascertained PH-AKI to date, demonstrating once again the considerable risk associated with developing even mild elevations in serum creatinine. Mortality rates varied considerably across centres and those identified as outliers will now need to carefully interrogate local care pathways to understand and address the reasons for this, with national policy required to tackle the identified health disparities.

Outcomes of patients with COVID-19 on kidney replacement therapy: a comparison among modalities in England.

BACKGROUND: Chronic kidney disease is a recognized risk factor of poor outcomes from coronavirus disease 2019 (COVID-19). METHODS: This retrospective cohort study used the UK Renal Registry database of people on kidney replacement therapy (KRT) at the end of 2019 in England and who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between 1 March 2020 and 31 August 2020 to analyse the incidence and outcomes of COVID-19 among different KRT modalities. Comparisons with 2015-2019 mortality data were used to estimate excess deaths. RESULTS: A total of 2783 individuals on KRT tested positive for SARS-CoV-2. Patients from more-deprived areas {most deprived versus least deprived hazard ratio [HR] 1.20 [95% confidence interval (CI) 1.04-1.39]} and those with diabetes compared with those without [HR 1.51 (95% CI 1.39-1.64)] were more likely to test positive. Approximately 25% of in-centre haemodialysis and transplanted patients died within 28 days of testing positive compared with 36% of those on home therapies. Mortality was higher in those ≥80 years of age compared with those 60-79 years [odds ratio (OR) 1.71 (95% CI 1.34-2.19)] and much lower in those listed for transplantation compared with those not listed [OR 0.56 (95% CI 0.40-0.80)]. Overall, excess mortality in 2020 for people on KRT was 36% higher than the 2015-2019 average. Excess deaths peaked in April 2020 at the height of the pandemic and were characterized by wide ethnic and regional disparities. CONCLUSIONS: The impact of COVID-19 on the English KRT population highlights their extreme vulnerability and emphasizes the need to protect and prioritize this group for vaccination. COVID-19 has widened underlying inequalities in people with kidney disease, making interventions that address health inequalities a priority.

Acute kidney injury identification for pharmacoepidemiologic studies: Use of laboratory electronic acute kidney injury alerts versus electronic health records in Hospital Episode Statistics.

PURPOSE: A laboratory-based acute kidney injury (AKI) electronic-alert (e-alert) system, with e-alerts sent to the UK Renal Registry (UKRR) and collated in a master patient index (MPI), has recently been implemented in England. The aim of this study was to determine the degree of correspondence between the UKRR-MPI and AKI International Classification Disease-10 (ICD-10) N17 coding in Hospital Episode Statistics (HES) and whether hospital N17 coding correlated with 30-day mortality and emergency re-admission after AKI. METHODS: AKI e-alerts in people aged ≥18 years, collated in the UKRR-MPI during 2017, were linked to HES data to identify a hospitalised AKI population. Multivariable logistic regression was used to analyse associations between absence/presence of N17 codes and clinicodemographic features. Correlation of the percentage coded with N17 and 30-day mortality and emergency re-admission after AKI were calculated at hospital level. RESULTS: In 2017, there were 301 540 adult episodes of hospitalised AKI in England. AKI severity was positively associated with coding in HES, with a high degree of inter-hospital variability-AKI stage 1 mean of 48.2% [SD 14.0], versus AKI stage 3 mean of 83.3% [SD 7.3]. N17 coding in HES depended on demographic features, especially age (18-29 years vs. ≥85 years OR 0.22, 95% CI 0.21-0.23), as well as sex and ethnicity. There was no evidence of association between the proportion of episodes coded for AKI with short-term AKI outcomes. CONCLUSION: Coding of AKI in HES is influenced by many factors that result in an underestimation of AKI. Using e-alerts to triangulate the true incidence of AKI could provide a better understanding of the factors that affect hospital coding, potentially leading to improved coding, patient care and pharmacoepidemiologic research.

The association of blood pressure variability with adverse outcomes in a primary care chronic kidney disease cohort.

BACKGROUND: Hypertension is common in individuals with chronic kidney disease and both conditions are associated with adverse outcomes including cardiovascular morbidity. Therefore, it is clinically important to identify methods of risk prediction in individuals with chronic kidney disease. Blood pressure variability has recently emerged as a predictor of cardiovascular events and mortality in the general population, with growing evidence indicating that it may play a similar role in individuals with chronic kidney disease. However, there have been no large studies assessing blood pressure variability in individuals with chronic kidney disease in primary care, where the majority of these patients are managed. METHOD: Using a retrospective observational study design, we analyzed routinely collected blood pressure readings from 16 999 individuals in The Leicester and County Chronic Kidney Disease cohort. Standard deviation, coefficient of variation and average real variability of SBP were used to calculate blood pressure variability. RESULTS: During a median follow-up of 5.0 (IQR 3.3--5.0) years, 2053 (12.1%) patients had cardiovascular events, death occurred in 5021 (29.6%) individuals and 156 (0.9%) individuals had endstage kidney disease events. In adjusted models, standard deviation and coefficient of variation were associated with cardiovascular events, all-cause mortality and endstage kidney disease. Average real variability was associated with all-cause mortality and cardiovascular events, but not endstage kidney disease. CONCLUSION: Blood pressure variability may be an accessible, routinely collected, noninvasive measure for stratifying the risk of adverse events in individuals with chronic kidney disease in a primary care setting.

Comorbidities and outcomes in South Asian individuals with chronic kidney disease: an observational primary care cohort.

BACKGROUND: South Asian (SA) individuals are more likely to develop end-stage renal disease (ESRD), but how chronic kidney disease (CKD) differs in relation to demographics, comorbidities and outcomes has not been studied. We aimed to study differences in SA individuals with CKD compared with White individuals. METHODS: This was an observational CKD cohort comparing SA with White individuals. Inclusion criteria were ≥18 years of age and two or more Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) eGFRs <60 mL/min/1.73 m2 >3 months apart. Individuals with ESRD at baseline were excluded. Baseline characteristics, including eGFR formulae [CKD-EPI and CKD-EPI-Pakistan (CKD-EPI-PK)], were compared. Analysis using competing risk regression for cardiovascular (CV) and ESRD events and Cox proportional hazard model for mortality was performed. RESULTS: From an adult population of 277 248 individuals, 17 248 individuals had CKD, of whom 1990 (11.5%) were of SA ethnicity. Age-adjusted prevalence of CKD was similar between ethnicities. SA individuals were more likely to be male, younger and socioeconomically deprived, and to have diabetes mellitus, CV disease and advanced CKD. Mean CKD-EPI-PK eGFR was 6.5 mL/min/1.73 m2 lower (41.1 versus 47.6, 95% confidence interval for difference 6.47-6.56) than for CKD-EPI. During 5 years of follow-up, 5109 (29.6%) individuals died, 2072 (12.0%) had a CV and 156 (0.90%) an ESRD event. Risk for SA individuals was higher for ESRD, similar to CV events and lower for mortality. Each 1 mL/min/1.73 m2 decrease in CKD-EPI-PK was associated with a 13.1% increased ESRD risk (adjusted subdistribution hazard ratio 0.869, 95% confidence interval 0.841-0.898). CONCLUSIONS: SA individuals with CKD were younger and had more advanced disease than White individuals. Risk of ESRD was higher and CKD-EPI-PK was associated with ESRD risk in SA individuals. Specific CKD interventions, including the use of CKD-EPI-PK, should be considered in SA populations.

Sociodemographic features and mortality of individuals on haemodialysis treatment who test positive for SARS-CoV-2: A UK Renal Registry data analysis.

Kidney disease is a recognised risk factor for poor COVID-19 outcomes. Up to 30 June 2020, the UK Renal Registry (UKRR) collected data for 2,385 in-centre haemodialysis (ICHD) patients with COVID-19 in England and Wales. Overall unadjusted survival at 1 week after date of positive COVID-19 test was 87.5% (95% CI 86.1-88.8%); mortality increased with age, treatment vintage and there was borderline evidence of Asian ethnicity (HR 1.16, 95% CI 0.94-1.44) being associated with higher mortality. Compared to the general population, the relative risk of mortality for ICHD patients with COVID-19 was 45.4 and highest in younger adults. This retrospective cohort study based on UKRR data supports efforts to protect this vulnerable patient group.