Reassuring pregnancy outcomes in women with mild COL4A3-5-related disease (Alport syndrome) and genetic type of disease can aid personalized counseling

Individualized pre-pregnancy counseling and antenatal care for women with chronic kidney disease (CKD) require disease-specific data. Here, we investigated pregnancy outcomes and long-term kidney function in women with COL4A3-5 related disease (Alport Syndrome, (AS)) in a large multicenter cohort. The ALPART-network (mAternaL and fetal PregnAncy outcomes of women with AlpoRT syndrome), an international collaboration of 17 centers, retrospectively investigated COL4A3-5 related disease pregnancies after the 20th week. Outcomes were stratified per inheritance pattern (X-Linked AS (XLAS)), Autosomal Dominant AS (ADAS), or Autosomal Recessive AS (ARAS)). The influence of pregnancy on estimated glomerular filtration rate (eGFR)-slope was assessed in 192 pregnancies encompassing 116 women (121 with XLAS, 47 with ADAS, and 12 with ARAS). Median eGFR pre-pregnancy was over 90ml/min/1.73m2. Neonatal outcomes were favorable: 100% live births, median gestational age 39.0 weeks and mean birth weight 3135 grams. Gestational hypertension occurred during 23% of pregnancies (reference: 'general' CKD G1-G2 pregnancies incidence is 4-20%) and preeclampsia in 20%. The mean eGFR declined after pregnancy but remained within normal range (over 90ml/min/1.73m2). Pregnancy did not significantly affect eGFR-slope (pre-pregnancy β=-1.030, post-pregnancy β=-1.349). ARAS-pregnancies demonstrated less favorable outcomes (early preterm birth incidence 3/11 (27%)). ARAS was a significant independent predictor for lower birth weight and shorter duration of pregnancy, next to the classic predictors (pre-pregnancy kidney function, proteinuria, and chronic hypertension) though missing proteinuria values and the small ARAS-sample hindered analysis. This is the largest study to date on AS and pregnancy with reassuring results for mild AS, though inheritance patterns could be considered in counseling next to classic risk factors. Thus, our findings support personalized reproductive care and highlight the importance of investigating kidney disease-specific pregnancy outcomes.

Anemia in Pregnancy With CKD

Chronic kidney disease (CKD), anemia, and iron deficiency are global health issues affecting individuals in both high-income and low-income countries. In pregnancy, both CKD and iron deficiency anemia increase the risk of adverse maternal and neonatal outcomes, including increased maternal morbidity and mortality, stillbirth, perinatal death, preterm birth, and low birthweight. However, it is unknown to which extent iron deficiency anemia contributes to adverse outcomes in CKD pregnancy. Furthermore, little is known regarding the prevalence, pathophysiology, and treatment of iron deficiency and anemia in pregnant women with CKD. Therefore, there are many unanswered questions regarding optimal management with oral or i.v. iron and recombinant human erythropoietin (rhEPO) in these women. In this review, we present a short overview of the (patho)physiology of anemia in healthy pregnancy and in people living with CKD. We present an evaluation of the literature on iron deficiency, anemia, and nutritional deficits in pregnant women with CKD; and we evaluate current knowledge gaps. Finally, we propose research priorities regarding anemia in pregnant women with CKD.

Effects of rare kidney diseases on kidney failure: a longitudinal analysis of the UK National Registry of Rare Kidney Diseases (RaDaR) cohort

BACKGROUND

Individuals with rare kidney diseases account for 5-10% of people with chronic kidney disease, but constitute more than 25% of patients receiving kidney replacement therapy. The National Registry of Rare Kidney Diseases (RaDaR) gathers longitudinal data from patients with these conditions, which we used to study disease progression and outcomes of death and kidney failure.

METHODS

People aged 0-96 years living with 28 types of rare kidney diseases were recruited from 108 UK renal care facilities. The primary outcomes were cumulative incidence of mortality and kidney failure in individuals with rare kidney diseases, which were calculated and compared with that of unselected patients with chronic kidney disease. Cumulative incidence and Kaplan-Meier survival estimates were calculated for the following outcomes: median age at kidney failure; median age at death; time from start of dialysis to death; and time from diagnosis to estimated glomerular filtration rate (eGFR) thresholds, allowing calculation of time from last eGFR of 75 mL/min per 1·73 m2 or more to first eGFR of less than 30 mL/min per 1·73 m2 (the therapeutic trial window).

FINDINGS

Between Jan 18, 2010, and July 25, 2022, 27 285 participants were recruited to RaDaR. Median follow-up time from diagnosis was 9·6 years (IQR 5·9-16·7). RaDaR participants had significantly higher 5-year cumulative incidence of kidney failure than 2·81 million UK patients with all-cause chronic kidney disease (28% vs 1%; p<0·0001), but better survival rates (standardised mortality ratio 0·42 [95% CI 0·32-0·52]; p<0·0001). Median age at kidney failure, median age at death, time from start of dialysis to death, time from diagnosis to eGFR thresholds, and therapeutic trial window all varied substantially between rare diseases.

INTERPRETATION

Patients with rare kidney diseases differ from the general population of individuals with chronic kidney disease: they have higher 5-year rates of kidney failure but higher survival than other patients with chronic kidney disease stages 3-5, and so are over-represented in the cohort of patients requiring kidney replacement therapy. Addressing unmet therapeutic need for patients with rare kidney diseases could have a large beneficial effect on long-term kidney replacement therapy demand.

FUNDING

RaDaR is funded by the Medical Research Council, Kidney Research UK, Kidney Care UK, and the Polycystic Kidney Disease Charity.

Pregnancy-associated changes in urinary uromodulin excretion in chronic hypertension

BACKGROUND

Pregnancy involves major adaptations in renal haemodynamics, tubular, and endocrine functions. Hypertensive disorders of pregnancy are a leading cause of maternal mortality and morbidity. Uromodulin is a nephron-derived protein that is associated with hypertension and kidney diseases. Here we study the role of urinary uromodulin excretion in hypertensive pregnancy.

METHODS

Urinary uromodulin was measured by ELISA in 146 pregnant women with treated chronic hypertension (n = 118) and controls (n = 28). We studied non-pregnant and pregnant Wistar Kyoto and Stroke Prone Spontaneously Hypertensive rats (n = 8/strain), among which a group of pregnant Stroke-Prone Spontaneously Hypertensive rats was treated with either nifedipine (n = 7) or propranolol (n = 8).

RESULTS

In pregnant women, diagnosis of chronic hypertension, increased maternal body mass index, Black maternal ethnicity and elevated systolic blood pressure at the first antenatal visit were significantly associated with a lower urinary uromodulin-to-creatinine ratio. In rodents, pre-pregnancy urinary uromodulin excretion was twofold lower in Stroke-Prone Spontaneously Hypertensive rats than in Wistar Kyoto rats. During pregnancy, the urinary uromodulin excretion rate gradually decreased in Wistar Kyoto rats (a twofold decrease), whereas a 1.5-fold increase was observed in Stroke-Prone Spontaneously Hypertensive rats compared to pre-pregnancy levels. Changes in uromodulin were attributed by kidney injury in pregnant rats. Neither antihypertensive changed urinary uromodulin excretion rate in pregnant Stroke-Prone Spontaneously Hypertensive rats.

CONCLUSIONS

In summary, we demonstrate pregnancy-associated differences in urinary uromodulin: creatinine ratio and uromodulin excretion rate between chronic hypertensive and normotensive pregnancies. Further research is needed to fully understand uromodulin physiology in human pregnancy and establish uromodulin's potential as a biomarker for renal adaptation and renal function in pregnancy.

The development and internal pilot trial of a digital physical activity and emotional well-being intervention (Kidney BEAM) for people with chronic kidney disease

This trial assessed the feasibility and acceptability of Kidney BEAM, a physical activity and emotional well-being self-management digital health intervention (DHI) for people with chronic kidney disease (CKD), which offers live and on-demand physical activity sessions, educational blogs and videos, and peer support. In this mixed-methods, multicentre randomised waitlist-controlled internal pilot, adults with established CKD were recruited from five NHS hospitals and randomised 1:1 to Kidney BEAM or waitlist control. Feasibility outcomes were based upon a priori progression criteria. Acceptability was primarily explored via individual semi-structured interviews (n = 15). Of 763 individuals screened, n = 519 (68%, 95% CI 65 to 71%) were eligible. Of those eligible, n = 303 (58%, 95% CI 54-63%) did not respond to an invitation to participate by the end of the pilot period. Of the 216 responders, 50 (23%, 95% CI 18-29%) consented. Of the 42 randomised, n = 22 (10 (45%) male; 49 ± 16 years; 14 (64%) White British) were allocated to Kidney BEAM and n = 20 (12 (55%) male; 56 ± 11 years; 15 (68%) White British) to the waitlist control group. Overall, n = 15 (30%, 95% CI 18-45%) withdrew during the pilot phase. Participants completed a median of 14 (IQR 5-21) sessions. At baseline, 90-100% of outcome data (patient reported outcome measures and a remotely conducted physical function test) were completed and 62-83% completed at 12 weeks follow-up. Interview data revealed that remote trial procedures were acceptable. Participants' reported that Kidney BEAM increased their opportunity and motivation to be physically active, however, lack of time remained an ongoing barrier to engagement with the DHI. An randomised controlled trial of Kidney BEAM is feasible and acceptable, with adaptations to increase recruitment, retention and engagement.Trial registration NCT04872933. Date of first registration 05/05/2021.

Evaluating the effect of a digital health intervention to enhance physical activity in people with chronic kidney disease (Kidney BEAM): a multicentre, randomised controlled trial in the UK

BACKGROUND

Remote digital health interventions to enhance physical activity provide a potential solution to improve the sedentary behaviour, physical inactivity, and poor health-related quality of life that are typical of chronic conditions, particularly for people with chronic kidney disease. However, there is a need for high-quality evidence to support implementation in clinical practice. The Kidney BEAM trial evaluated the clinical effect of a 12-week physical activity digital health intervention on health-related quality of life.

METHODS

In a single-blind, randomised controlled trial conducted at 11 centres in the UK, adult participants (aged ≥18 years) with chronic kidney disease were recruited and randomly assigned (1:1) to the Kidney BEAM physical activity digital health intervention or a waiting list control group. Randomisation was performed with a web-based system, in randomly permuted blocks of six. Outcome assessors were masked to treatment allocation. The primary outcome was the difference in the Kidney Disease Quality of Life Short Form version 1.3 Mental Component Summary (KDQoL-SF1.3 MCS) between baseline and 12 weeks. The trial was powered to detect a clinically meaningful difference of 3 arbitrary units (AU) in KDQoL-SF1.3 MCS. Outcomes were analysed by an intention-to-treat approach using an analysis of covariance model, with baseline measures and age as covariates. The trial was registered with ClinicalTrials.gov, NCT04872933.

FINDINGS

Between May 6, 2021, and Oct 30, 2022, 1102 individuals were assessed for eligibility, of whom 340 participants were enrolled and randomly assigned to the Kidney BEAM intervention group (n=173) or the waiting list control group (n=167). 268 participants completed the trial (112 in the Kidney BEAM group and 156 in the waiting list control group). All 340 randomly assigned participants were included in the intention-to treat population. At 12 weeks, there was a significant improvement in KDQoL-SF.13 MCS score in the Kidney BEAM group (from mean 44·6 AU [SD 10·8] at baseline to 47·0 AU [10·6] at 12 weeks) compared with the waiting list control group (from 46·1 AU [10·5] to 45·0 AU [10·1]; between-group difference of 3·1 AU [95% CI 1·8-4·4]; p<0·0001).

INTERPRETATION

The Kidney BEAM physical activity platform is an efficacious digital health intervention to improve mental health-related quality of life in patients with chronic kidney disease. These findings could facilitate the incorporation of remote digital health interventions into clinical practice and offer a potential intervention worthy of investigation in other chronic conditions.

FUNDING

Kidney Research UK.

Removal of ethnicity adjustment for creatinine-based estimated glomerular filtration rate equations

Creatinine-based estimated glomerular filtration rate equations (eGFRcreatinine) are used to measure excretory kidney function in clinical practice. Despite inter and intra-patient variability, eGFRcreatinine has excellent clinical utility and provides the basis for the classification system for chronic kidney disease (CKD), for kidney function monitoring, treatment interventions and referral pathways. The 4-variable modification of diet in renal disease (MDRD) eGFRcreatinine equation was introduced in 2000 and recommended by the National Institute for Health and Care Excellence (NICE) in 2008. Subsequently, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) eGFRcreatinine equation was introduced in 2009 and is more accurate than MDRD in patients with mild and moderate CKD. In 2014, NICE recommended that CKD-EPI eGFRcreatinine replace MDRD eGFRcreatinine in routine clinical practice across England. Both equations originally incorporated adjustments for age, gender and ethnicity. However, the evidence for ethnicity adjustment has been increasingly questioned, and in 2021 NICE recommended that kidney function should be estimated by CKD-EPI eGFRcreatinine without using ethnicity adjustment. Recently, a CKD-EPI equation has been presented without ethnicity adjustment; however, this has not been validated outside of North America and NICE continues to recommend CKD-EPI 2009. We review the status of eGFRcreatinine in clinical practice, including the limitations of eGFRcreatinine and the rationale for removal of ethnicity adjustment and the potential impact of this change on clinical care for patients with kidney disease.

Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

INTRODUCTION

The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures.

METHODS

In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025.

FINDINGS

Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2-6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5-5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4-10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32-4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23-11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation.

INTERPRETATION

After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Female Infertility in Chronic Kidney Disease

This review summarises the current literature regarding infertility in women with chronic kidney disease (CKD), describing the epidemiology, pathophysiology, investigations, and management options. The pathophysiology is multifactorial, with proposed mechanisms including disruption of the hypothalamus-pituitary-ovarian axis, chronic inflammation, oxidative stress, psychological factors, and gonadotoxic effects of medications such as cyclophosphamide. Diagnostic investigations in CKD patients seeking to conceive should be considered earlier than in the healthy population. Investigations should include hormonal profiling, including markers such as Anti-Mullerian Hormone and imaging such as ultrasound, to evaluate ovarian reserve and identify gynaecology pathology. Treatment options for infertility in CKD patients include GnRH agonists to preserve ovarian function during cyclophosphamide treatment, as well as assisted reproductive technologies including in vitro fertilisation and ovulation induction. However, these treatments must be tailored to the individual's health status, comorbidities, fertility requirements, and CKD stage. In conclusion, fertility is an important consideration for women with CKD, necessitating early investigation and tailored management. Early discussions regarding fertility are important in order to understand patients' family planning and allow for prompt referral to fertility services. While challenges exist, ongoing research aims to clarify the underlying mechanism and optimise treatment strategies, which are crucial for improving quality of life and overall health outcomes.

High rates of psychological distress, mental health diagnoses and suicide attempts in people with chronic kidney disease in Ireland

BACKGROUND

People with chronic kidney disease (CKD) experience high levels of psychological distress, which is associated with higher mortality and adverse health outcomes. Little is known about the rates of a range of mental health difficulties or rates of suicide attempts in people with CKD.

METHODS

Individuals with CKD (n = 268; age range 18-94 years, mean = 49.96 years) on haemodialysis (n = 79), peritoneal dialysis (n = 46), transplant recipients (n = 84) and who were not on renal replacement therapy (RRT; n = 59) were recruited through the Irish Kidney Association social media pages and three Irish hospitals. Participants completed surveys to gather demographics and mental health histories, the Hospital Anxiety and Depression Scale (HADS) and the 12-item Short Form Health Survey (SF-12) to measure health-related quality of life (HRQoL).

RESULTS

A total of 23.5% of participants self-reported they had received a mental health diagnosis, with depression (14.5%) and anxiety (14.2%) being the most common, while 26.4% of participants had experienced suicidal ideation and 9.3% had attempted suicide. Using a clinical cut-off ≥8 on the HADS subscales, current levels of clinically significant anxiety and depression were 50.7% and 35.4%, respectively. Depression levels were slightly higher for those on haemodialysis compared with those with a transplant and those not on RRT. Depression, anxiety and having a mental health diagnosis were all associated with lower HRQoL.

CONCLUSIONS

People with CKD in Ireland experience high levels of psychological distress, mental health difficulties, suicidal ideation and suicide attempts. The identification of and intervention for mental health difficulties in CKD should be prioritised in clinical care.

CRADLE-5: a stepped-wedge type 2 hybrid implementation-effectiveness cluster randomised controlled trial to evaluate the real-world scale-up of the CRADLE Vital Signs Alert intervention into routine maternity care in Sierra Leone-study protocol

BACKGROUND

The CRADLE Vital Signs Alert intervention (an accurate easy-to-use device that measures blood pressure and pulse with inbuilt traffic-light early warning system, and focused training package) was associated with reduced rates of eclampsia and maternal death when trialled in urban areas in Sierra Leone. Subsequently, implementation was successfully piloted as evidenced by measures of fidelity, feasibility and adoption. The CRADLE-5 trial will examine whether national scale-up, including in the most rural areas, will reduce a composite outcome of maternal and fetal mortality and maternal morbidity and will evaluate how the CRADLE package can be embedded sustainably into routine clinical pathways.

METHODS

CRADLE-5 is a stepped-wedge cluster-randomised controlled trial of the CRADLE intervention compared to routine maternity care across eight rural districts in Sierra Leone (Bonthe, Falaba, Karene, Kailahun, Koinadugu, Kono, Moyamba, Tonkolili). Each district will cross from control to intervention at six-weekly intervals over the course of 1 year (May 2022 to June 2023). All women identified as pregnant or within six-weeks postpartum presenting for maternity care in the district are included. Primary outcome data (composite rate of maternal death, stillbirth, eclampsia and emergency hysterectomy) will be collected. A mixed-methods process and scale-up evaluation (informed by Medical Research Council guidance for complex interventions and the World Health Organization ExpandNet tools) will explore implementation outcomes of fidelity, adoption, adaptation and scale-up outcomes of reach, maintenance, sustainability and integration. Mechanisms of change and contextual factors (barriers and facilitators) will be assessed. A concurrent cost-effectiveness analysis will be undertaken.

DISCUSSION

International guidance recommends that all pregnant and postpartum women have regular blood pressure assessment, and healthcare staff are adequately trained to respond to abnormalities. Clinical effectiveness to improve maternal and perinatal health in more rural areas, and ease of integration and sustainability of the CRADLE intervention at scale has yet to be investigated. This trial will explore whether national scale-up of the CRADLE intervention reduces maternal and fetal mortality and severe maternal adverse outcomes and understand the strategies for adoption, integration and sustainability in low-resource settings. If successful, the aim is to develop an adaptable, evidence-based scale-up roadmap to improve maternal and infant outcomes.

TRIAL REGISTRATION

ISRCTN 94429427. Registered on 20 April 2022.

The NightLife study - the clinical and cost-effectiveness of thrice-weekly, extended, in-centre nocturnal haemodialysis versus daytime haemodialysis using a mixed methods approach: study protocol for a randomised controlled trial

BACKGROUND

In-centre nocturnal haemodialysis (INHD) offers extended-hours haemodialysis, 6 to 8 h thrice-weekly overnight, with the support of dialysis specialist nurses. There is increasing observational data demonstrating potential benefits of INHD on health-related quality of life (HRQoL). There is a lack of randomised controlled trial (RCT) data to confirm these benefits and assess safety.

METHODS

The NightLife study is a pragmatic, two-arm, multicentre RCT comparing the impact of 6 months INHD to conventional haemodialysis (thrice-weekly daytime in-centre haemodialysis, 3.5-5 h per session). The primary outcome is the total score from the Kidney Disease Quality of Life tool at 6 months. Secondary outcomes include sleep and cognitive function, measures of safety, adherence to dialysis and impact on clinical parameters. There is an embedded Process Evaluation to assess implementation, health economic modelling and a QuinteT Recruitment Intervention to understand factors that influence recruitment and retention. Adults (≥ 18 years old) who have been established on haemodialysis for > 3 months are eligible to participate.

DISCUSSION

There are 68,000 adults in the UK that need kidney replacement therapy (KRT), with in-centre haemodialysis the treatment modality for over a third of cases. HRQoL is an independent predictor of hospitalisation and mortality in individuals on maintenance dialysis. Haemodialysis is associated with poor HRQoL in comparison to the general population. INHD has the potential to improve HRQoL. Vigorous RCT evidence of effectiveness is lacking. The NightLife study is an essential step in the understanding of dialysis therapies and will guide patient-centred decisions regarding KRT in the future.

TRIAL REGISTRATION

Trial registration number: ISRCTN87042063. Registered: 14/07/2020.

A Randomized Trial of Intravenous Iron Supplementation and Exercise on Exercise Capacity in Iron-Deficient Nonanemic Patients With CKD

Introduction

Patients with chronic kidney disease (CKD) are often iron deficient, even when not anemic. This trial evaluated whether iron supplementation enhances exercise capacity of nonanemic patients with CKD who have iron-deficiency.

Methods

Prospective, multicenter double-blind randomized controlled trial of nondialysis patients with CKD and iron-deficiency but without anemia (Hemoglobin [Hb] >110 g/l). Patients were assigned 1:1 to intravenous (IV) iron therapy, or placebo. An 8-week exercise program commenced at week 4. The primary outcome was the mean between-group difference in 6-minute walk test (6MWT) at 4 weeks. Secondary outcomes included 6MWT at 12 weeks, transferrin saturation (TSAT), serum ferritin (SF), Hb, renal function, muscle strength, functional capacity, quality of life, and adverse events at baseline, 4 weeks, and at 12 weeks. Mean between-group differences were analyzed using analysis of covariance models.

Results

Among 75 randomized patients, mean (SD) age for iron therapy (n = 37) versus placebo (n = 38) was 54 (16) versus 61 (12) years; estimated glomerular filtration rate (eGFR) (34 [12] vs. 35 [11] ml/min per 1.73 m2], TSAT (23 [12] vs. 21 [6])%; SF (57 [64] vs. 62 [33]) μg/l; Hb (122.4 [9.2] vs. 127 [13.2] g/l); 6MWT (384 [95] vs. 469 [142] meters) at baseline, respectively. No significant mean between-group difference was observed in 6MWT distance at 4 weeks. There were significant increases in SF and TSAT at 4 and 12 weeks (P < 0.02), and Hb at 12 weeks (P = 0.009). There were no between-group differences in other secondary outcomes and no adverse events attributable to iron therapy.

Conclusion

This trial did not demonstrate beneficial effects of IV iron therapy on exercise capacity at 4 weeks. A larger study is needed to confirm if IV iron is beneficial in nondialysis patients with CKD who are iron-deficient.

Health Inequalities in kiDney Disease, mEeting the urgent Need to identify early disease in high-risk communities: a feasibility study of home albuminuria testing in people with high Blood Pressure (HIDDEN-BP)

BACKGROUND

Chronic kidney disease (CKD) is prevalent in the UK, associated with significant mortality and morbidity, and disproportionately affects minority ethnic groups. The most common causes for CKD are diabetes and hypertension. An estimated glomerular function (eGFR) blood test and an albumin creatinine ratio (uACR) urine test can be used to assess the level of CKD and predict the risk of adverse outcomes such as cardiovascular disease, end stage renal failure, and death. However, UK National CKD audit data suggest that only 30% of those with hypertension have a recorded uACR. Our quality improvement project working with community stakeholders and Healthy.io digital enterprise will evaluate the feasibility of uACR self-testing in the community.

AIM

To promote uACR testing using smartphone home self-testing kits (Heathy.io) to improve the early diagnosis of CKD in individuals with hypertension.

METHOD

Individuals with hypertension in three GP practices in ethnically diverse areas in London will be invited to use a home self-testing uACR kit. Healthy.io (providers of kit) will complete patient enrolment and make one attempt to contact non-responders. Non-responders will be offered peer support to assist engagement. Qualitative data will be sought regarding the acceptability of the test for both clinicians and patients.

RESULTS

We will recruit three practices in South London and mail 200 digital urine testing kits. Uptake and results will be presented.

CONCLUSION

Improving equity in uACR testing through quality improvement tools can deliver a sustainable project for improving patient renal care. Leveraging innovative methods provides the potential for effective, equitable, and efficient services.

Improving kidney care for people with severe mental health difficulties: a thematic analysis of twenty-two healthcare providers' perspectives

Introduction

People with severe mental health difficulties (SMHDs) and concurrent kidney disease have less access to quality kidney care and worse clinical outcomes. Our research investigates the barriers and facilitators to effective kidney care for people with SMHDs, and how care might be improved for this underserved population.

Methods

We conducted semi-structured interviews with twenty-two physical (n = 14) and mental (n = 8) healthcare professionals with experience working with people with SMHDs and concurrent kidney disease. Interview data were analysed and interpreted using reflexive thematic analysis.

Results

Four themes were generated from the data: 1. "It's about understanding their limitations and challenges, without limiting their rights" describes how some people with SMHDs need additional support when accessing kidney care due to challenges with their mental state, motivation, cognitive difficulties, or mistrust of the healthcare system. 2. "There are people falling through the cracks" describes how the separation of physical and mental healthcare, combined with under-resourcing and understaffing, results in poorer outcomes for people with SMHDs. 3. "Psychiatry is a black spot in our continuing medical education" describes how many renal healthcare providers have limited confidence in their understanding of mental health and their ability to provide care for people with SMHDs. 4. "When they present to a busy emergency department with a problem, the staff tend to go '…psych patient"" describes how stigma towards people with SMHDs can negatively impact quality of care.

Conclusion

Healthcare professionals accounts' describe how people with SMHDs and kidney disease can have favourable outcomes if they have appropriate hospital, community and social supports. Findings indicate that effective management of kidney disease for people with SMHDs requires integrated physical and mental health care, which takes an individualised "whole person" approach to addressing the interaction between kidney disease and mental health.

Performance and pitfalls of the tools for measuring glomerular filtration rate to guide chronic kidney disease diagnosis and assessment

Accurate diagnosis, classification and risk stratification for chronic kidney disease (CKD) allow for early recognition and delivering optimal care. Creatinine-based glomerular filtration rate (GFR), urinary albumin: creatinine ratio (UACR) and the kidney failure risk equation (KFRE) are important tools to achieve this, but understanding their limitations is important for optimal implementation.When accurate GFR is required (eg, chemotherapy dosing), GFR is measured using an exogenous filtration marker. In routine clinical practice, in contrast, estimated GFR (eGFR) from serum creatinine (SCr), calculated using the enzymatic method±UACR, is recommended. Limitations of SCr include non-GFR determinants such as muscle mass, diet and tubular handling. An alternative or additional endogenous filtration marker is cystatin C, which can be used alongside SCr for confirmatory testing of CKD. However, its role in the UK is more limited due to concerns regarding false positive results.The recommended creatinine-based eGFR equation in the UK is the CKD Epidemiology Collaboration 2009 equation. This was recently updated to a race-neutral 2021 version and demonstrated reduced bias in people of Black ethnicity, but has not been validated in the UK. Limitations are extremes of age, inaccuracy at greater GFRs and reduced generalisability to under-represented ethnicity groups.The KFRE (based on age, sex, SCr and UACR) has recently been developed to help determine 2-year and 5-year risk of progression to end-stage kidney disease. It has been validated in over 30 countries and provides meaningful quantitative information to patients. However, supporting evidence for their performance in ethnic minority groups and kidney diseases such as glomerulonephritis remains modest.In conclusion, early identification, risk stratification of kidney disease and timely intervention are important to impact kidney disease progression. However, clinician awareness of the limitations and variability of creatinine, cystatin C and the eGFR equations, is key to appropriate interpretation of results.

The effect of a novel, digital physical activity and emotional well-being intervention on health-related quality of life in people with chronic kidney disease: trial design and baseline data from a multicentre prospective, wait-list randomised controlled trial (kidney BEAM)

BACKGROUND

Physical activity and emotional self-management has the potential to enhance health-related quality of life (HRQoL), but few people with chronic kidney disease (CKD) have access to resources and support. The Kidney BEAM trial aims to evaluate whether an evidence-based physical activity and emotional wellbeing self-management programme (Kidney BEAM) leads to improvements in HRQoL in people with CKD.

METHODS

This was a prospective, multicentre, randomised waitlist-controlled trial, with health economic analysis and nested qualitative studies. In total, three hundred and four adults with established CKD were recruited from 11 UK kidney units. Participants were randomly assigned to the intervention (Kidney BEAM) or a wait list control group (1:1). The primary outcome was the between-group difference in Kidney Disease Quality of Life (KDQoL) mental component summary score (MCS) at 12 weeks. Secondary outcomes included the KDQoL physical component summary score, kidney-specific scores, fatigue, life participation, depression and anxiety, physical function, clinical chemistry, healthcare utilisation and harms. All outcomes were measured at baseline and 12 weeks, with long-term HRQoL and adherence also collected at six months follow-up. A nested qualitative study explored experience and impact of using Kidney BEAM.

RESULTS

340 participants were randomised to Kidney BEAM (n = 173) and waiting list (n = 167) groups. There were 96 (55%) and 89 (53%) males in the intervention and waiting list groups respectively, and the mean (SD) age was 53 (14) years in both groups. Ethnicity, body mass, CKD stage, and history of diabetes and hypertension were comparable across groups. The mean (SD) of the MCS was similar in both groups, 44.7 (10.8) and 45.9 (10.6) in the intervention and waiting list groups respectively.

CONCLUSION

Results from this trial will establish whether the Kidney BEAM self management programme is a cost-effective method of enhancing mental and physical wellbeing of people with CKD.

TRIAL REGISTRATION

NCT04872933. Registered 5th May 2021.

Pre-eclampsia is associated with complement pathway activation in the maternal and fetal circulation, and placental tissue

OBJECTIVES

Pre-eclampsia (PE) is a leading cause of obstetric morbidity, with no definitive therapy other than delivery. We aimed to compare complement markers in maternal and fetal circulation, and placental tissue, between women with PE and healthy pregnant controls.

STUDY DESIGN

Maternal and umbilical cord blood was tested for iC3b, C3, C4, properdin, Ba and C5b-9, and placental tissue for C3d, C4d, C9 and C1q, from women with PE (n = 34) and healthy pregnant controls (n = 33). Maternal properdin and Ba tests were repeated in a separate validation cohort (PE n = 35; healthy pregnant controls n = 35).

MAIN OUTCOME MEASURES

Complement concentrations in maternal and umbilical cord blood, and placental immunohistochemical complement deposition.

RESULTS

Women with PE had significantly lower concentrations of properdin (mean: 4828 vs 6877 ng/ml, p < 0.001) and C4 (mean: 0.20 vs 0.31 g/l, p < 0.001), and higher Ba (median: 150 vs 113 ng/ml, p = 0.012), compared to controls. After controlling for gestational age at blood draw, average properdin concentration was 1945 ng/ml lower in PE vs controls (95 % CI: 1487-2402, p < 0.001). Of the cord blood markers assessed, only Ba differed significantly between PE and controls (median: 337 vs 233 ng/ml, p = 0.004). C4d staining of the syncytiotrophoblast membrane was increased in PE vs controls (median immunoreactivity score 3 vs 0, p < 0.001). Maternal properdin and C4 were significantly negatively correlated with placental C4d staining.

CONCLUSIONS

Our data confirm excessive placental complement deposition associated with significant concurrent changes in maternal and fetal circulating complement biomarkers in PE. Inhibition of complement activation is a potential therapeutic target.

Chronic kidney disease and severe mental illness: a scoping review

BACKGROUND

People who have severe mental illness experience higher rates of long-term conditions and die on average 15-20 years earlier than people who do not have severe mental illness, a phenomenon known as the mortality gap. Long-term conditions, such as diabetes, impact health outcomes for people who have severe mental illness, however there is limited recognition of the relationship between chronic kidney disease and severe mental illness. Therefore, the aim of this scoping review was to explore the available evidence on the relationship between chronic kidney disease and severe mental illness.

METHODS

Electronic databases, including MEDLINE, Embase, CINAHL, and PsycINFO were searched. The database searches were limited to articles published between January 2000-January 2022, due to significant progress that has been made in the detection, diagnosis and treatment of both SMI and CKD. Articles were eligible for inclusion if they explored the relationship between SMI and CKD (Stages 1-5) in terms of prevalence, risk factors, clinical outcomes, and access to treatment and services. Severe mental illness was defined as conditions that can present with psychosis, including schizophrenia, schizoaffective disorder, bipolar disorder, and other psychotic disorders. Thirty articles were included in the review.

RESULTS

The included studies illustrated that there is an increased risk of chronic kidney disease amongst people who have severe mental illness, compared to those who do not. However, people who have severe mental illness and chronic kidney disease are less likely to receive specialist nephrology care, are less likely to be evaluated for a transplant, and have higher rates of mortality.

CONCLUSION

In conclusion, there is a dearth of literature in this area, but the available literature suggests there are significant health inequalities in kidney care amongst people who have severe mental illness. Further research is needed to understand the factors that contribute to this relationship, and to develop strategies to improve both clinical outcomes and access to kidney care.

Ethnic disparities in pregnancy-related acute kidney injury in a United Kingdom population

BACKGROUND

The incidence of acute kidney injury in pregnancy (P-AKI) is rising and is associated with detrimental maternal and foetal outcomes. Ethnic disparities in pregnancy outcomes are well recognized, with females who identify as Black or Asian being more likely to die during pregnancy compared to females who identify as White ethnicity.

METHODS

This study reports rates of P-AKI and associated risk factors in pregnant females of different ethnicities. All pregnancies were recorded between 2016 and 2020. AKI episodes were identified using electronic alerts. Ethnicity, AKI stage (1-3), obstetric outcomes and risk factors for P-AKI (chronic hypertension, pregnancy-induced hypertension and pre-eclampsia, and haemorrhage) were assessed.

RESULTS

There were 649 P-AKI episodes from 16,943 deliveries (3.8%). Black females were more likely to have P-AKI (5.72%) compared to those who were White (3.12%), Asian (3.74%), mixed ethnicity (2.89%) and Other/Not Stated (3.10%). Black females, compared to White females, were at greater risk of developing P-AKI if they had haemorrhage requiring blood transfusion (OR 2.44, 95% CI 1.31,4.54; p < 0.001) or pregnancy-induced hypertension (OR 1.79, 95% CI 1.12, 2.86; p < 0.001). After adjusting for risk factors, Black females had increased risk of developing P-AKI (OR 1.52, 95% CI 1.22, 1.80; p < 0.001) compared to White females. Black females were at increased risk of developing P-AKI compared to White females. Mode of delivery, pregnancy-induced hypertension and haemorrhage are likely to have contributed. The increased risk persists despite accounting for these variables, suggesting that other factors such as socioeconomic disparities need to be considered.

CONCLUSIONS

The incidence of P-AKI is likely higher than previously stated in the literature. However, caution must be exercised, particularly with AKI stage 1, as the KDIGO system is not validated in pregnancy and gestational changes in renal physiology need to be considered. Pregnancy-specific AKI definitions are needed.

Exploring biopsychosocial correlates of pregnancy risk and pregnancy intention in women with chronic kidney disease

INTRODUCTION

Women with Chronic Kidney Disease (CKD) are at increased risk of adverse pregnancy and renal outcomes. It is unknown how women with CKD understand their pregnancy risk. This nine-centre, cross-sectional study aimed to explore how women with CKD perceive their pregnancy risk and its impact on pregnancy intention, and identify associations between biopsychosocial factors and perception of pregnancy risk and intention.

METHODS

Women with CKD in the UK completed an online survey measuring their pregnancy preferences; perceived CKD severity; perception of pregnancy risk; pregnancy intention; distress; social support; illness perceptions and quality of life. Clinical data were extracted from local databases. Multivariable regression analyses were performed. Trial registration: NCT04370769.

RESULTS

Three hundred fifteen women participated, with a median estimated glomerular filtration rate (eGFR) of 64 ml/min/1.73m² (IQR 56). Pregnancy was important or very important in 234 (74%) women. Only 108 (34%) had attended pre-pregnancy counselling. After adjustment, there was no association between clinical characteristics and women's perceived pregnancy risk nor pregnancy intention. Women's perceived severity of their CKD and attending pre-pregnancy counselling were independent predictors of perceived pregnancy risk. Importance of pregnancy was an independent predictor of pregnancy intention but there was no correlation between perceived pregnancy risk and pregnancy intention (r = - 0.002, 95% CI - 0.12 to 0.11).

DISCUSSION

Known clinical predictors of pregnancy risk for women with CKD were not associated with women's perceived pregnancy risk nor pregnancy intention. Importance of pregnancy in women with CKD is high, and influences pregnancy intention, whereas perception of pregnancy risk does not.

Inaxaplin for Proteinuric Kidney Disease in Persons with Two APOL1 Variants

BACKGROUND

Persons with toxic gain-of-function variants in the gene encoding apolipoprotein L1 (APOL1) are at greater risk for the development of rapidly progressive, proteinuric nephropathy. Despite the known genetic cause, therapies targeting proteinuric kidney disease in persons with two APOL1 variants (G1 or G2) are lacking.

METHODS

We used tetracycline-inducible APOL1 human embryonic kidney (HEK293) cells to assess the ability of a small-molecule compound, inaxaplin, to inhibit APOL1 channel function. An APOL1 G2-homologous transgenic mouse model of proteinuric kidney disease was used to assess inaxaplin treatment for proteinuria. We then conducted a single-group, open-label, phase 2a clinical study in which inaxaplin was administered to participants who had two APOL1 variants, biopsy-proven focal segmental glomerulosclerosis, and proteinuria (urinary protein-to-creatinine ratio of ≥0.7 to <10 [with protein and creatinine both measured in grams] and an estimated glomerular filtration rate of ≥27 ml per minute per 1.73 m² of body-surface area). Participants received inaxaplin daily for 13 weeks (15 mg for 2 weeks and 45 mg for 11 weeks) along with standard care. The primary outcome was the percent change from the baseline urinary protein-to-creatinine ratio at week 13 in participants who had at least 80% adherence to inaxaplin therapy. Safety was also assessed.

RESULTS

In preclinical studies, inaxaplin selectively inhibited APOL1 channel function in vitro and reduced proteinuria in the mouse model. Sixteen participants were enrolled in the phase 2a study. Among the 13 participants who were treated with inaxaplin and met the adherence threshold, the mean change from the baseline urinary protein-to-creatinine ratio at week 13 was -47.6% (95% confidence interval, -60.0 to -31.3). In an analysis that included all the participants regardless of adherence to inaxaplin therapy, reductions similar to those in the primary analysis were observed in all but 1 participant. Adverse events were mild or moderate in severity; none led to study discontinuation.

CONCLUSIONS

Targeted inhibition of APOL1 channel function with inaxaplin reduced proteinuria in participants with two APOL1 variants and focal segmental glomerulosclerosis. (Funded by Vertex Pharmaceuticals; VX19-147-101 ClinicalTrials.gov number, NCT04340362.).

6 Cortical hypoperfusion on intensive care unit admission identifies the development of acute kidney injury. The microshock renal study

Background

UK Defence has a vested interest in shock resuscitation and has limited access to renal replacement therapy. The aetiology of acute kidney injury (AKI) as a component of multiorgan failure is unclear and experimental data is conflicting. Clinical evidence is equally limited and novel methods of assessing the kidney in critical illness are needed. We assessed renal perfusion in septic shock using a novel method of contrast enhanced ultrasound (CEUS).

Methods

Longitudinal observational study of 50 patients at four timepoints commenced within 24 hours of admission, two of the groups were defined retrospectively by the occurrence or absence of severe AKI. Contrast ultrasound was administered by infusion with subsequent replenishment kinetics. Renal artery Doppler ultrasonography, transthoracic echocardiography, sublingual video microscopy and biomarkers were measured to determine macro-haemodynamics, the severity of tubular damage and AKI subphenotype. Identical observations were performed in healthy controls, the third group. The primary outcome was the cortical perfusion differences between groups. Secondary outcomes were perfusion differences between subphenotypes, correlation of renal and sublingual microcirculatory perfusion and the differences in renal and global macro-haemodynamics.

Results

Patients with septic shock have reduced cortical perfusion in comparison to healthy controls (average cortical mean transit time (mTT) 13.6s vs 2.2s p<0.0001) and patients who develop severe AKI have reduced perfusion from admission to ICU in comparison to patients without severe AKI (cortical mTT 16.1s vs 7.2s p=0.006). These differences are independent of both cardiac output (6.1l vs 5.7l, p=0.6) and renal artery blood flow (1.56l/min vs 1.81l/min, p=0.4). Biomarker data to identify perfusion abnormalities in AKI subphenotypes are awaited.

Conclusion

Cortical hypoperfusion is detectable on admission to ICU using CEUS and identifies patients who will develop severe AKI. This paves the way for interventional study, individualizing renal resuscitation with vasoactive therapies.

Chronic Kidney Disease and Severe Mental Illness: Addressing Disparities in Access to Health Care and Health Outcomes

Individuals with severe mental illness, including conditions such as schizophrenia and bipolar disorder, are at a higher risk of developing CKD. Higher incidences of CKD in this population can be partially explained by known risk factors, such as the use of lithium treatment and higher rates of cardiovascular disease. However, this does not fully explain the higher proportion of CKD in individuals with severe mental illness, and further research investigating the factors influencing disease onset and progression is needed. Similarly, although it is well documented that mental health difficulties, such as depression and anxiety, are highly prevalent among individuals with CKD, there is a lack of published data regarding the rates of severe mental illness in individuals with CKD. Furthermore, for individuals with CKD, having severe mental illness is associated with poor health outcomes, including higher mortality rates and higher rates of hospitalizations. Evidence also suggests that individuals with severe mental illness receive suboptimal kidney care, have fewer appointments with nephrologists, and are less likely to receive a kidney transplant. Limited research suggests that care might be improved through educating kidney health care staff regarding the needs of patients with severe mental illness and by facilitating closer collaboration with psychiatry. Further research investigating the rates of severe mental illness in patients with CKD, as well as the barriers and facilitators to effective care for this population, is clearly required to inform the provision of appropriate supports and to improve health outcomes for individuals with CKD and co-occurring severe mental illness.

Decreased renal cortical perfusion, independent of changes in renal blood flow and sublingual microcirculatory impairment, is associated with the severity of acute kidney injury in patients with septic shock

Background

Reduced renal perfusion has been implicated in the development of septic AKI. However, the relative contributions of macro- and microcirculatory blood flow and the extent to which impaired perfusion is an intrinsic renal phenomenon or part of a wider systemic shock state remains unclear.

Methods

Single-centre prospective longitudinal observational study was carried out. Assessments were made at Day 0, 1, 2 and 4 after ICU admission of renal cortical perfusion in 50 patients with septic shock and ten healthy volunteers using contrast-enhanced ultrasound (CEUS). Contemporaneous measurements were made using transthoracic echocardiography of cardiac output. Renal artery blood flow was calculated using velocity time integral and vessel diameter. Assessment of the sublingual microcirculation was made using handheld video microscopy. Patients were classified based on the degree of AKI: severe = KDIGO 3 v non-severe = KDIGO 0–2.

Results

At study enrolment, patients with severe AKI (37/50) had prolonged CEUS mean transit time (mTT) (10.2 vs. 5.5 s, p < 0.05), and reduced wash-in rate (WiR) (409 vs. 1203 au, p < 0.05) and perfusion index (PI) (485 vs. 1758 au, p < 0.05); differences persisted throughout the entire study. Conversely, there were no differences in either cardiac index, renal blood flow or renal resistive index. Sublingual microcirculatory variables were not significantly different between groups at study enrolment or at any subsequent time point. Although lactate was higher in the severe AKI group at study enrolment, these differences did not persist, and there were no differences in either ScvO2 or ScvCO2-SaCO2 between groups. Patients with severe AKI received higher doses of noradrenaline (0.34 vs. 0.21mcg/kg/min, p < 0.05). Linear regression analysis showed no correlation between mTT and cardiac index (R-0.18) or microcirculatory flow index (R-0.16).

Conclusion

Renal cortical hypoperfusion is a persistent feature in critically ill septic patients who develop AKI and does not appear to be caused by reductions in macrovascular renal blood flow or cardiac output. Cortical hypoperfusion appears not be associated with changes in the sublingual microcirculation, raising the possibility of a specific renal pathogenesis that may be amenable to therapeutic intervention.

Trial Registration Clinical Trials.gov NCT03713307, 19 Oct 2018.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

The effect of intravenous iron supplementation on exercise capacity in iron-deficient but not anaemic patients with chronic kidney disease: study design and baseline data for a multicentre prospective double-blind randomised controlled trial

BACKGROUND

Many people living with chronic kidney disease (CKD) are iron deficient, even though they may not be anaemic. The Iron and Muscle study aims to evaluate whether iron supplementation reduces symptoms of fatigue, improves muscle metabolism, and leads to enhanced exercise capacity and physical function. We report here the trial design and baseline characteristics.

METHODS

This is a prospective, double-blind multicentre randomised controlled trial (RCT) including 75 non-dialysis stage 3-4 CKD patients with iron deficiency but without anaemia. Patients were randomly (1:1) assigned to either: i) intravenous iron therapy, or ii) placebo, with concurrent recruitment of eight CKD non-iron deficient participants and six healthy volunteers. The primary outcome of the study is the six-minute walk test (6MWT) distance between baseline and four-weeks. An additional exercise training programme for patients in both groups was initiated and completed between 4 and 12 weeks, to determine the effect of iron repletion compared to placebo treatment in the context of patients undertaking an exercise programme. Additional secondary outcomes include fatigue, physical function, muscle strength, muscle metabolism, quality of life, resting blood pressure, clinical chemistry, safety and harms associated with the iron therapy intervention and the exercise training intervention, and hospitalisations. All outcomes were conducted at baseline, 4, and 12 weeks, with a nested qualitative study, to investigate the experience of living with iron deficiency and intervention acceptability. The cohort have been recruited and baseline assessments undertaken.

RESULTS

Seventy-five individuals were recruited. 44% of the randomised cohort were male, the mean (SD) age was 58 (14) years, and 56% were White. Body mass index was 31 (7) kg/m²; serum ferritin was 59 (45) μg/L, transferrin saturation was 22 (10) %, and haemoglobin was 125 (12) g/L at randomisation for the whole group. Estimated glomerular filtration rate was 35 (12) mL/min/1.73 m² and the baseline 6MWT distance was 429 (174) m.

CONCLUSION

The results from this study will address a substantial knowledge gap in the effects of intravenous iron therapy, and offer potential clinical treatment options, to improve exercise capacity, physical function, fatigue, and muscle metabolism, for non-dialysis patients with CKD who are iron-deficient but not anaemic. It will also offer insight into the potential novel effects of an 8-week exercise training programme.

TRIAL REGISTRATION

EudraCT: 2018-000,144-25 Registered 28/01/2019.

Outcome and effect of vaccination in SARS-CoV-2 Omicron infection in hemodialysis patients: a cohort study

Background

Hemodialysis patients are at high risk of Covid-19, though vaccination has significant efficacy in preventing and reducing the severity of infection. Little information is available on disease severity and vaccine efficacy since the dissemination of the Omicron variant.

Methods

In a multi-center study, during a period of the epidemic driven by the Omicron variant, all hemodialysis patients positive for SARS-CoV-2 were identified. Outcomes were analyzed according to predictor variables including vaccination status. Risk of infection was analyzed using a Cox proportional hazards model.

Results

SARS-CoV-2 infection was identified in 1126 patients including 200 (18%) unvaccinated, 56 (5%) post first dose, 433 (38%) post second dose, and 437 (39%) at least 7 days beyond their third dose. The majority of patients had a mild course but 160 (14%) were hospitalized and 28 (2%) died. In regression models adjusted for age and comorbidity, two-dose vaccination was associated with a 39% (95%CI: 2%–62%) reduction in admissions, but third doses provided additional protection, with a 51% (95%CI: 25%–69%) further reduction in admissions. Among 1265 patients at risk at the start of the observation period, SARS-CoV-2 infection was observed in 211 (17%). Two-dose vaccination was associated with a 41% (95%CI: 3%–64%) reduction in the incidence of infection, with no clear additional effect provided by third doses.

Conclusions

These data demonstrate lower incidence of SARS-CoV-2 infection after vaccination in dialysis patients during an Omicron dominant period of the epidemic. Among those developing infection, severe illness was less common with prior vaccination, particularly after third vaccine doses.

Severity of COVID-19 after Vaccination among Hemodialysis Patients: An Observational Cohort Study

BACKGROUND AND OBJECTIVES

Patients receiving hemodialysis are at high risk from coronavirus disease 2019 (COVID-19) and demonstrate impaired immune responses to vaccines. There have been several descriptions of their immunologic responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, but few studies have described the clinical efficacy of vaccination in patients on hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In a multicenter observational study of the London hemodialysis population undergoing surveillance PCR testing during the period of vaccine rollout with BNT162b2 and AZD1222, all of those positive for SARS-CoV-2 were identified. Clinical outcomes were analyzed according to predictor variables, including vaccination status, using a mixed effects logistic regression model. Risk of infection was analyzed in a subgroup of the base population using a Cox proportional hazards model with vaccination status as a time-varying covariate.

RESULTS

SARS-CoV-2 infection was identified in 1323 patients of different ethnicities (Asian/other, 30%; Black, 38%; and White, 32%), including 1047 (79%) unvaccinated, 86 (7%) after first-dose vaccination, and 190 (14%) after second-dose vaccination. The majority of patients had a mild course; however, 515 (39%) were hospitalized, and 172 (13%) died. Older age, diabetes, and immune suppression were associated with greater illness severity. In regression models adjusted for age, comorbidity, and time period, prior two-dose vaccination was associated with a 75% (95% confidence interval, 56 to 86) lower risk of admission and 88% (95% confidence interval, 70 to 95) fewer deaths compared with unvaccinated patients. No loss of protection was seen in patients over 65 years or with increasing time since vaccination, and no difference was seen between vaccine types.

CONCLUSIONS

These data demonstrate a substantially lower risk of severe COVID-19 after vaccination in patients on dialysis who become infected with SARS-CoV-2.

The Feasibility and User-Experience of a Digital Health Intervention Designed to Prevent Weight Gain in New Kidney Transplant Recipients—The ExeRTiOn2 Trial

Half of kidney transplant recipients (KTRs) gain more than 5% of their body weight in the first year following transplantation. KTRs have requested support with physical activity (PA) and weight gain prevention, but there is no routine care offered. There are few high-quality studies investigating the clinical value of diet, PA or combined interventions to prevent weight gain. The development and evaluation of theoretically informed complex-interventions to mitigate weight gain are warranted. The aims of this mixed-methods randomized controlled trial (RCT) were to explore the feasibility, acceptability and user-experience of a digital healthcare intervention (DHI) designed to prevent post-transplant weight gain, in preparation for a large multi-center trial. New KTRs (<3 months) with access to an internet compatible device were recruited from a London transplant center. The usual care (UC) group received standard dietary and PA advice. The intervention group (IG) received access to a 12-week DHI designed to prevent post-transplant weight gain. Primary feasibility outcomes included screening, recruitment, retention, adherence, safety and hospitalizations and engagement and experience with the DHI. Secondary outcomes (anthropometrics, bioimpedance, arterial stiffness, 6-minute walk distance and questionnaires) were measured at baseline, 3- and 12-months. 38 KTRs were screened, of which 32 (84.2%) were eligible, and of those 20 (62.5%) consented, with 17 participants (85%) completing baseline assessment (Median 49 years, 58.8% male, Median 62 days post-transplant). Participants were randomized using a computer-generated list (n = 9 IG, n = 8 UC). Retention at 12-months was 13 (76.4%) (n = 6 IG, n = 7 UC). All a priori progression criteria were achieved. There were no associated adverse events. Reflexive thematic analysis revealed four themes regarding trial participation and experience whilst using the DHI. Halting recruitment due to COVID-19 resulted in the recruitment of 40% of the target sample size. Mixed-methods data provided important insights for future trial design. A definitive RCT is warranted and welcomed by KTRs.

MO1044: Understanding Perception of Pregnancy Risk in Women with Chronic Kidney Disease

BACKGROUND AND AIMS

Women with chronic kidney disease (CKD) are at increased risk of adverse pregnancy and renal outcomes, including preterm birth and progression of kidney disease. Women's risk perceptions of pregnancy impact behaviours and decisions including engagement with prenatal care, mode of delivery choices and adherence to medical advice, therefore, it is important that women perceive and understand their risk accurately. Pre-pregnancy counselling is recommended for all women with CKD, but it is unknown how women with CKD understand their pregnancy risk and if pre-pregnancy counselling affects women's perceptions. The aim of this study was to understand how a large cohort of diverse women with CKD perceive their pregnancy risk and compare differences in risk perceptions between those who have and have not received pre-pregnancy counselling.

METHOD

The ‘Perception of Pregnancy Risk Questionnaire’ (PPRQ;1) and ‘Desire to Avoid Pregnancy Questionnaire’ (2) were used to measure risk perception and pregnancy intention respectively. The PPRQ was adapted to assess risk perceptions in women with CKD including the severity of kidney disease. Content validity of the adapted PPRQ was confirmed by a panel of 21 experts including nephrologists, midwives, psychologists and obstetricians. Women aged between 18 and 50 years with CKD stages 1–5 were recruited from nine renal units in the United Kingdom and asked to complete an online survey (October 2020–December 2021). Clinical data were extracted from local databases. Data were analysed descriptively.

RESULTS

A total of 322 women completed the survey, mean age of 34.9 (SD 7.1) years. Women's obstetric history and pregnancy perspectives are described in the Table. Half of the respondents already had children (172/322; 54.1%) and three-quarters perceived pregnancy to be important or very important to themselves (241/322; 75.8%) and two-thirds (218/322; 66.7%) perceived pregnancy to be important or very important to their family. Only 109/321 (34%) of women with CKD had previously attended pre-pregnancy counselling, but those who had attended had a higher perception of pregnancy risk [51.4 (SD 21.4) versus 41.9 (SD 23.8); P < 0.0001] (0: not very severe to 100: extremely severe) and severity of kidney disease [51.3 (SD 24.9) versus 43.7 (SD 28.6); P = 0.014] compared to women who had not attended pre-pregnancy counselling.

CONCLUSION

This large multi-centre questionnaire study identified that risk perceptions of pregnancy for women with CKD appear to be higher than those of women with an uncomplicated pregnancy [PPRQ scores of 24.0 (SD 14.5)] [1]. However, women who had received pre-pregnancy counselling had a significantly higher perception of pregnancy risk and perceived severity of kidney disease. Limitations include a lack of measurement before and after attending a pre-pregnancy counselling clinic. Further assessment of the relationship between severity of kidney disease and perceived pregnancy risk and pregnancy intentions is needed.

MO170: Systematic Review of Patients with Chronic Kidney Disease Undergoing Fertility Treatment

BACKGROUND AND AIMS

The prevalence of chronic kidney disease (CKD) in women of reproductive age continues to rise and reduced fertility is recognized even with mild disease. A greater proportion of women with CKD are seeking assisted reproductive technology (ART) treatment; however, our understanding of treatment success and adverse outcomes is limited. Our aim was to perform a systematic review to describe pregnancy and kidney outcomes and complications of pregnancies in women with CKD following ART.

METHOD

The systematic review was performed with reference to the Cochrane Handbook for Systematic Reviews of Interventions and reported with reference to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The following databases were searched from 1946 to May 2021: (1) Cochrane Central Register of Controlled Trials (CENTRAL), (2) Cumulative Index to Nursing and Allied Health Literature (CINAHL), (3) Embase and (4) MEDLINE. Relevant review articles were also searched for additional studies.

RESULTS

The database search identified 3520 records, of which 35 publications were suitable for analysis. A total of 95 fertility treatment cycles were analysed in 74 women with CKD who had ART. The median age of women with CKD at the time of pregnancy was 32.0 years (IQR 29.0, 34.0 years).

The majority of women had in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) (56/74; 75.7%). One woman had an autotransplant of cryopreserved ovarian tissue which led to a spontaneous pregnancy, one woman had a medicated frozen embryo transfer cycle, one woman used donor eggs and five women used gestational surrogates.

Of the 95 cycles, 11 women (15%) did not have a clinical pregnancy; there were 66 clinical pregnancies from 63 women (69%). There were 81 live births in total, with 21 multifetal live births (26%). There was 1 ectopic pregnancy, 13 miscarriages and 2 still births.

Seven cycles in seven women were complicated by ovarian hyperstimulation syndrome (OHSS) (7%) which were all associated with AKI. Full recovery of kidney function occurred in six women; one woman had progression of her CKD. Hypertensive disorders of pregnancy including pre-eclampsia complicated 27 pregnancies (41%). The most common mode of delivery was caesarean section (42/74, 57%). Preterm delivery (&lt;37 weeks’ gestation) occurred in 25 (34%) births. Low birth weight (&lt;2500 g) was present in 46 (79%) of live births and 6 (20%) of birthweights were under the 10th centile. Twelve (15%) neonates required admission to a neonatal intensive care unit (NICU). A total of 7/12 children had normal development at up to 10 years of follow-up. When comparing women with CKD requiring ART to those with natural conception, rates of preterm delivery and caesarean section were similar; however, rates of pre-eclampsia (P = .001) and multifetal deliveries were significantly higher (P &lt; .001) in the ART cohort.

CONCLUSION

To our knowledge, this systematic review represents the most comprehensive assessment of fertility outcomes in patients with CKD who have assisted conception. Limitations include reporting bias due to a high reported live birth rate. Patient selection for fertility treatment and identification of risk factors remains crucial in order to maximize patient safety, screen for adverse events and optimise fertility outcomes.

MO589: Exertion2 Trial: THE Weight Gain Prevention in Renal Transplant Online Study—a Randomized Controlled Feasibility Trial

BACKGROUND AND AIMS

Adverse weight gain within the first year of receiving a kidney transplant is associated with adverse health outcomes. Kidney transplant recipients (KTRs) have asked for support with physical activity and following healthy lifestyles. There is no recognised intervention to address weight gain prevention for new KTRs. Usability of an online intervention to prevent weight gain in new KTRs has recently been reported. The aim of this study was to examine the feasibility of undertaking a randomised controlled trial of an online intervention group (IG) compared with usual care UC) to address weight gain prevention in new KTRs.

METHOD

Participants were recruited from two south-London transplant sites, had a kidney transplant within 3 months, and had access to an internet compatible device. Exclusion criteria included history of an unstable medical condition, non-English speaking or <18 years. At baseline assessment participants were randomized to either UC or IG. The UC group received standard dietary and physical activity education. The IG received access to a 12-week password-protected website, weekly email reminders, and could contact the research physiotherapist via a secure message function.

Primary feasibility outcomes included screening rates, consent rates, adherence to study visits, acceptability of outcomes, engagement with the intervention, retention, willingness to be randomized, adverse events, hospitalizations, experience using the online intervention and experience taking part in the trial. Secondary outcomes were recorded at baseline, 3- and 12-months. These included body weight, body mass index (BMI), bioimpedance (BIA), pulse wave velocity (PWV), augmentation index (AI) and six-minute walk distance (6MWD).

RESULTS

Seventeen new KTRs (median age 49 years, 10 males, median 62 days post-transplant) were randomized to the IG (n = 9) or UC (n = 8). Screening rate was 84.2% (95% CI: 68.8–94.0), recruitment 62.5% (95% CI: 43.7–79.0) and intervention adherence at 12 months was 76.4% (95% CI: 50.0–93.2). All pre-set progression criteria for feasibility were achieved. There were no associated adverse events. Qualitative analysis revealed four themes; optimizing participation and recruitment, impact of Coronavirus disease 2019 (COVID-19), engagement is a choice (technical and personal factors) and mechanisms of action (assessment and intervention factors). The IG appeared to stabilize median body weight across the study; 94.5 kg, (IQR: 63.0, 102.0), 95.0 kg, (IQR: 66.7, 105.3) and 94.7 kg (IQR: 77.2, 117.3). Whereas UC participants increased [81.3 kg, (IQR: 73.6,94.6), 86.2 kg (75.4, 96.5) and 93.3 kg (70.3, 101.9)]. IG increased 6MWD [450 m, (IQR: 450, 540), 525 m (IQR: 472.5, 615) and 495 m (IQR: 465, 615)] and UC decreased 6MWD [517.5 m (IQR: 436, 570), 507.5 m (IQR: 442.5, 605) and 435 m (IQR 435, 555)]. All other outcomes were comparable across the sample.

CONCLUSION

Limitations include inadequate power and small sample size, and it was a single-centre study. Integrated mixed methods analysis demonstrate congruency of both qualitative and quantitative data. Participant attitudes, experiences and engagement with the study and intervention provide insight for future trial design. A future definitive trial is warranted and welcomed by KTRs.

Evaluation of novel coagulation and platelet function assays in patients with chronic kidney disease

BACKGROUND

Hemostasis evaluation in chronic kidney disease (CKD) is critical for optimal management of thrombotic and bleeding events. Standard coagulation screens are inadequate for predicting coagulopathy in CKD.

OBJECTIVE

To evaluate hemostasis parameters in patients with different stages of CKD using novel coagulation assays.

PATIENTS/METHODS

Cross-sectional study of 30 healthy controls (HC) and 120 CKD patients (10 Stage 2, 20 Stage 3, 20 Stage 4, 20 Stage 5 not requiring renal replacement therapy, 20 transplant, 10 newly started on hemodialysis [HD], 20 established on HD). Standard laboratory tests were performed in addition to rotational thromboelastometry (ROTEM), multiple electrode aggregometry (MEA), thrombin generation assays, D-dimer, and markers of thrombogenesis (thrombin-antithrombin [TAT]), fibrinolysis, and endothelial activation (intercellular adhesion molecule-1 [ICAM-1]).

RESULTS

D-dimer, TAT, and ICAM-1 concentrations were significantly higher in patients with CKD than HC (P < .01). ROTEM maximum clot firmness was significantly higher in patients than in HC (P < .01). In CKD Stage 5 patients (pre-HD and started HD) adenosine diphosphate and thrombin receptor activating peptide MEA tests were significantly lower than HC indicating platelet aggregation defect (P < .05). Multivariate analysis confirmed the direct effect of estimated glomerular filtration rate (eGFR) in the variance of ROTEM and MEA tests. Endogenous thrombin potential and peak thrombin were not statistically different between groups, but Stage 5 CKD patients had prolonged lag time (7.91 vs. 6.33, P < .001) and time to thrombin peak (10.8 vs. 9.5, P < .05) compared to HC.

CONCLUSIONS

Patients with CKD exhibit features of concomitant hypercoagulability measured by ROTEM and platelet dysfunction measured with MEA. eGFR was an independent determinant of platelet dysfunction and hypercoagulability.

Genetic Variants of APOL1 Are Major Determinants of Kidney Failure in People of African Ancestry With HIV

Introduction

Variants of the APOL1 gene are associated with chronic kidney disease (CKD) in people of African ancestry, although evidence for their impact in people with HIV are sparse.

Methods

We conducted a cross-sectional study investigating the association between APOL1 renal risk alleles and kidney disease in people of African ancestry with HIV in the UK. The primary outcome was end-stage kidney disease (ESKD; estimated glomerular filtration rate [eGFR] of <15 ml/min per 1.73 m2, chronic dialysis, or having received a kidney transplant). The secondary outcomes included renal impairment (eGFR <60 ml/min per 1.73 m2), albuminuria (albumin-to-creatinine ratio [ACR] >30 mg/mmol), and biopsy-proven HIV-associated nephropathy (HIVAN). Multivariable logistic regression was used to estimate the associations between APOL1 high-risk genotypes (G1/G1, G1/G2, G2/G2) and kidney disease outcomes.

Results

A total of 2864 participants (mean age 48.1 [SD 10.3], 57.3% female) were genotyped, of whom, 354 (12.4%) had APOL1 high-risk genotypes, and 99 (3.5%) had ESKD. After adjusting for demographic, HIV, and renal risk factors, individuals with APOL1 high-risk genotypes were at increased odds of ESKD (odds ratio [OR] 10.58, 95% CI 6.22-17.99), renal impairment (OR 5.50, 95% CI 3.81-7.95), albuminuria (OR 3.34, 95% CI 2.00-5.56), and HIVAN (OR 30.16, 95% CI 12.48-72.88). An estimated 49% of ESKD was attributable to APOL1 high-risk genotypes.

Conclusion

APOL1 high-risk genotypes were strongly associated with kidney disease in people of African ancestry with HIV and accounted for approximately half of ESKD cases in this cohort.

Sickle Cell Trait and Kidney Disease in People of African Ancestry With HIV

Introduction

Sickle cell trait (SCT) has been associated with chronic kidney disease (CKD) in African Americans, although evidence for its impact in Africans and people with HIV is currently lacking. We conducted a cross-sectional study investigating the association between SCT and kidney disease in people of African ancestry with HIV in the UK.

Methods

The primary outcome was estimated glomerular filtration rate (eGFR) <60 ml/min per 1.73 m2. Secondary outcomes were eGFR <90 ml/min per 1.73 m2, end-stage kidney disease (ESKD; eGFR <15 ml/min per 1.73 m2, chronic dialysis, or having received a kidney transplant), proteinuria (protein-to-creatinine ratio >50 mg/mmol), and albuminuria (albumin-to-creatinine ratio >3 mg/mmol). Multivariable logistic regression was used to estimate the associations between SCT and kidney disease outcomes.

Results

A total of 2895 participants (mean age 48.1 [SD 10.3], 57.2% female) were included, of whom 335 (11.6%) had SCT and 352 (12.2%) had eGFR <60 ml/min per 1.73 m2. After adjusting for demographic, HIV, and kidney risk factors including APOL1 high-risk genotype status, individuals with SCT were more likely to have eGFR <60 ml/min per 1.73 m2 (odds ratio 1.62 [95% CI 1.14-2.32]), eGFR <90 ml/min per 1.73 m2 (1.50 [1.14-1.97]), and albuminuria (1.50 [1.09-2.05]). Stratified by APOL1 status, significant associations between SCT and GFR <60 ml/min per 1.73 m2, eGFR <90 ml/min per 1.73 m2, proteinuria, and albuminuria were observed for those with APOL1 low-risk genotypes.

Conclusion

Our results extend previously reported associations between SCT and kidney disease to people with HIV. In people of African ancestry with HIV, these associations were largely restricted to those with APOL1 low-risk genotypes.

Rule-in and rule-out of pre-eclampsia using DELFIA Xpress PlGF 1-2-3 and sFlt-1: PlGF ratio

OBJECTIVES

The objective of this study was to explore and validate thresholds for Placental growth factor (PlGF) and soluble fms-like tyrosine-kinase 1 (s-Flt-1) (as s-Flt-1: PlGF ratio), to rule-in and rule-out disease in women with suspected pre-eclampsia, using DELFIA® Xpress PlGF1-2-3 and sFlt-1 assays.

STUDY DESIGN

369 samples from women with suspected or confirmed pre-eclampsia were analysed from a prospective cohort study.

MAIN OUTCOME MEASURES

Serum PlGF and sFlt-1: PlGF were quantified using DELFIA® Xpress PlGF1-2-3 and DELFIA® Xpress sFlt-1 tests. Performances were evaluated at established and exploratory thresholds. Low PlGF concentration and sFlt-1: PlGF AUROC were compared.

RESULTS

PlGF 1-2-3 concentration thresholds were confirmed to have high performance for rule-in (<50 pg/ml) and rule-out (≥150 pg/ml) pre-eclampsia within seven days (20-33⁺⁶ Weeks <50 pg/ml: Negative predictive value (NPV) 90.7% (95% CI 83.9, 95.3); ≥150 pg/ml: NPV 94.8% (95% CI 88.4, 98.3)) and 28 days (20-33⁺⁶ Weeks <50 pg/ml: Negative predictive value (NPV) 83.9% (95% CI 76.0, 90.0); ≥150 pg/ml: NPV 92.8% (95% CI 85.7, 97.0)). Optimal sFlt-1: PlGF thresholds for rule-in were ≥ 70 before 34 weeks and ≥ 90 after 34 weeks, and <50 to rule-out pre-eclampsia. Low PlGF alone had comparable performance to sFlt-1: PlGF, but test performance for both was reduced in women with Kidney Disease.

CONCLUSIONS

DELFIA® Xpress PlGF1-2-3 and sFlt-1 assays for pre-eclampsia rule-in and rule-out have comparable performance to other established assays, and could be an alternative for clinical use. Performance was not enhanced by use of sFlt-1: PlGF ratio, suggesting that PlGF alone could provide a cheaper alternative to dual biomarker testing.

Correction to: COVID-19-related acute kidney injury; incidence, risk factors and outcomes in a large UK cohort

An amendment to this paper has been published and can be accessed via the original article.

COVID-19-related acute kidney injury; incidence, risk factors and outcomes in a large UK cohort

BACKGROUND

Acute kidney injury (AKI) is common among patients hospitalised with COVID-19 and associated with worse prognosis. The aim of this study was to investigate the epidemiology, risk factors and outcomes of AKI in patients with COVID-19 in a large UK tertiary centre.

METHODS

We analysed data of consecutive adults admitted with a laboratory-confirmed diagnosis of COVID-19 across two sites of a hospital in London, UK, from 1st January to 13th May 2020.

RESULTS

Of the 1248 inpatients included, 487 (39%) experienced AKI (51% stage 1, 13% stage 2, and 36% stage 3). The weekly AKI incidence rate gradually increased to peak at week 5 (3.12 cases/100 patient-days), before reducing to its nadir (0.83 cases/100 patient-days) at the end the study period (week 10). Among AKI survivors, 84.0% had recovered renal function to pre-admission levels before discharge and none required on-going renal replacement therapy (RRT). Pre-existing renal impairment [odds ratio (OR) 3.05, 95%CI 2.24-4,18; p <  0.0001], and inpatient diuretic use (OR 1.79, 95%CI 1.27-2.53; p <  0.005) were independently associated with a higher risk for AKI. AKI was a strong predictor of 30-day mortality with an increasing risk across AKI stages [adjusted hazard ratio (HR) 1.59 (95%CI 1.19-2.13) for stage 1; p < 0.005, 2.71(95%CI 1.82-4.05); p < 0.001for stage 2 and 2.99 (95%CI 2.17-4.11); p < 0.001for stage 3]. One third of AKI3 survivors (30.7%), had newly established renal impairment at 3 to 6 months.

CONCLUSIONS

This large UK cohort demonstrated a high AKI incidence and was associated with increased mortality even at stage 1. Inpatient diuretic use was linked to a higher AKI risk. One third of survivors with AKI3 exhibited newly established renal impairment already at 3-6 months.

APOL1 genotypes: Do they contribute to ethnicity-associated biological health inequalities in pregnancy?

Inferior health outcomes for people of African and Afro-Caribbean ancestry compared to those of European ancestry are well recognised. There is a disproportionate impact within these communities compared to other ethnic groups including pregnancy outcomes, hypertension, kidney disease and diabetes. The ‘Black Lives Matter’ movement has highlighted that it is imperative to examine all factors contributing to this inequity and to strive to explore multifaceted ways, including social, economic, psychological and biological to improve overall health equity. It is within this context that we discuss the novel finding of Apolipoprotein 1 genetic polymorphisms which have been identified in some populations of African ancestry. We will explore the history and evolutionary advantages of Apolipoprotein 1 polymorphisms and the pathophysiology resulting from these adaptations and examine the impact of Apolipoprotein 1 on pregnancy outcomes, the risks and benefits of screening for high-risk Apolipoprotein 1 alleles in black communities and potential treatments currently being investigated.

Pregnancy and CKD: Advances in Care and the Legacy of Dr Susan Hou

Dr Susan Hou began her illustrious nephrology career at a time when pregnancy in women with chronic kidney disease (CKD) was hazardous and actively discouraged. Her pioneering research in women's health provided much of the early outcome data that shaped our current understanding of CKD and pregnancy. Although many uncertainties regarding optimal management of this vulnerable patient group remain, recent decades have witnessed important advances and renewed interest in improving care for pregnant women with CKD. Many nephrologists have been inspired by Dr Hou's lifetime of work and are grateful for her generous collaborations. In this In Practice Review, we honor her legacy by providing an update of current literature and clinical management guidance in the context of a clinical case vignette that challenges us to consider the many complex aspects to the counseling and care of women with CKD who desire a pregnancy.

Estimated glomerular filtration rate equations in people of self-reported black ethnicity in the United Kingdom: Inappropriate adjustment for ethnicity may lead to reduced access to care

Assessment in African populations suggest adjustment for ethnicity in estimated glomerular filtration rate (eGFR) equations derived from African Americans lead to overestimation of GFR and failure to determine severity in chronic kidney disease (CKD). However, studies in African Europeans are limited. We aimed to assess accuracy of eGFR equations, with and without ethnicity adjustment compared with measured GFR in people of Black ethnicity in the United Kingdom. Performance of MDRD, CKD-EPI (with and without ethnicity adjustment), Full Age Spectrum (FAS), revised Lund Malmö (LM Revised), and European Kidney Function Consortium (EKFC) eGFR equations were assessed compared to ⁵¹Cr-EDTA GFR studies extracted from hospital databases. Participants with albumin <30g/l, liver disease, <18 years, of non-Black or non-White self-reported ethnicity were excluded. Agreement was assessed by bias, precision and 30%-accuracy and was stratified for ethnicity and GFR. 1888 ⁵¹Cr-EDTA studies were included (Mean age-53.7yrs; 43.6% female; 14.1% Black ethnicity). Compared to White participants, eGFR-MDRD and eGFR-CKD-EPI equations in Black participants significantly overestimated GFR (bias 20.3 and 19.7 ml/min/1.73m² respectively, p<0.001). Disregarding the ethnicity adjustment significantly improved GFR estimates for Black participants (bias 6.7 and 2.4ml/min/1.73m² for eGFR-MDRD and eGFR-CKD-EPI respectively, p<0.001). The LM Revised equation had the smallest bias for both White and Black participants (5.8ml and -1.1ml/min/1.73m² respectively). 30%-accuracy was superior for GFR≥60ml/min/1.73m² compared to <60ml/min/1.73m² using eGFR-CKD-EPI equation for both White and Black participants (p<0.001). Multivariate regression methodology with adjustment for age, sex and log(serum creatinine) in the cohort yielded an ethnicity coefficient of 1.018 (95% CI: 1.009–1.027). Overestimation of measured GFR with eGFR equations using ethnicity adjustment factors may lead to reduced CKD diagnosis and under-recognition of severity in people of Black ethnicity. Our findings suggest that ethnicity adjustment for GFR estimation in non-African Americans may not be appropriate for use in people of Black ethnicity in the UK.

The epidemiology of kidney disease in people of African ancestry with HIV in the UK

BACKGROUND

Chronic kidney disease (CKD) is a leading cause of morbidity and mortality globally. The risk of CKD is increased in people of African ancestry and with Human Immunodeficiency Virus (HIV) infection.

METHODS

We conducted a cross-sectional study investigating the relationship between region of ancestry (East, Central, South or West Africa) and kidney disease in people of sub-Saharan African ancestry with HIV in the UK between May 2018 and February 2020. The primary outcome was renal impairment (estimated glomerular filtration rate [eGFR] of <60 mL/min/1.73 m2). Secondary outcomes were stage 5 CKD (eGFR <15 ml/min/1.73 m2, on dialysis for over 3 months or who had received a kidney transplant), proteinuria (urine protein/creatinine ratio >50 mg/mmol), and biopsy-confirmed HIV-associated nephropathy (HIVAN), focal segmental glomerulosclerosis (FSGS) or arterionephrosclerosis. Multivariable robust Poisson regression estimated the effect of region of African ancestry on kidney disease outcomes.

FINDINGS

Of the 2468 participants (mean age 48.1 [SD 9.8] years, 62% female), 193 had renal impairment, 87 stage 5 CKD, 126 proteinuria, and 43 HIVAN/FSGS or arterionephrosclerosis. After adjusting for demographic characteristics, HIV and several CKD risk factors and with East African ancestry as referent, West African ancestry was associated with renal impairment (prevalence ratio [PR] 2.06 [95% CI 1.40-3.04]) and stage 5 CKD (PR 2.23 [1.23-4.04]), but not with proteinuria (PR 1.27 [0.78-2.05]). West African ancestry (as compared to East/South African ancestry) was also strongly associated with a diagnosis of HIVAN/FSGS or arterionephrosclerosis on kidney biopsy (PR 6.44 [2.42-17.14]).

INTERPRETATION

Our results indicate that people of West African ancestry with HIV are at increased risk of kidney disease. Although we cannot rule out the possibility of residual confounding, geographical region of origin appears to be a strong independent risk factor for CKD as the association did not appear to be explained by several demographic, HIV or renal risk factors.