Long-term changes in cardiac remodelling in prevalent kidney graft recipients

BACKGROUND

Approximately 15% of kidney transplant (KT) recipients develop de novo heart failure after KT. There are scarce data reporting the long-term changes in cardiac structure and function among KT recipients. Despite the improvement in renal function, transplant-related complications as well as immunosuppressive therapy could have an impact on cardiac remodelling during follow-up. We aimed to describe the long-term changes in echocardiographic parameters in prevalent KT recipients and identify the clinical and laboratory factors associated with these changes.

METHODS

A centralised blinded review of two echocardiographic examinations after KT (on average after 17 and 39 months post-KT respectively) was performed among 80 patients (age 50.4 ± 16.2, diabetes 13.8% pre-KT), followed by linear regression to identify clinico-biological factors related to echocardiographic changes.

RESULTS

Left atrial volume index (LAVI) increased significantly (34.2 ± 10.8 mL/m2vs. 37.6 ± 15.0 mL/m2, annualised delta 3.1 ± 11.4 mL/m2/year; p = 0.034) while left ventricular ejection fraction (LVEF) decreased (62.1 ± 9.0% vs. 59.7 ± 9.9%, annualised delta -2.7 ± 13.6%/year; p = 0.04). Male sex (β = 8.112 ± 2.747; p < 0.01), pre-KT hypertension (β = 9.725 ± 4.156; p < 0.05), graft from expanded criteria donor (β = 3.791 ± 3.587; p < 0.05), and induction by anti-thymocyte globulin (β = 7.920 ± 2.974; p = 0.01) were associated with an increase in LAVI during follow-up. Higher haemoglobin (>12.9 g/dL) at the time of the first echocardiography (β = 6.029 ± 2.967; p < 0.05) and ACEi/ARB therapy (β = 8.306 ± 3.161; p < 0.05) were associated with an increase in LVEF during follow-up.

CONCLUSION

This study confirms the existence of long-term cardiac remodelling after KT despite dialysis cessation, characterised by an increase in LAVI and a decrease in LVEF. A better management of anaemia and using ACEi/ARB therapy may prevent such remodelling.

The number of nephroprotection targets attained is associated with cardiorenal outcomes and mortality in patients with diabetic kidney disease. The CKD-REIN cohort study

AIM

The risk of cardiorenal events remains high among patients with diabetes and chronic kidney disease (CKD), despite the prescription of recommended treatments. We aimed to determine whether the attainment of a combination of nephroprotection targets at baseline (glycated haemoglobin <7.0%, urinary albumin-creatinine ratio <300 mg/g, blood pressure <130/80 mmHg, renin-angiotensin system inhibition) was associated with better cardiorenal outcomes and lower mortality.

MATERIALS AND METHODS

From the prospective French CKD-REIN cohort, we studied 1260 patients with diabetes and CKD stages 3-4 (estimated glomerular filtration rate: 15-60 ml/min/1.73 m2); 69% were men, and at inclusion, mean ± SD age: 70 ± 10 years; estimated glomerular filtration rate: 33 ± 11 ml/min/1.73 m2. The median follow-up was 4.9 years.

RESULTS

In adjusted Cox regression models, the attainment of two nephroprotection targets was consistently associated with a lower risk of cardiorenal events [hazard ratio 0.70 (95% confidence interval 0.57-0.85)], incident kidney failure with replacement therapy [0.58 (0.43-0.77)], four major adverse cardiovascular events (cardiovascular death, myocardial infarction, stroke, hospitalization for heart failure) [0.75 (0.57-0.99)] and all-cause mortality [0.59 (0.42-0.82)] when compared with the attainment of zero or one target. For patients with a urinary albumin-creatinine ratio ≥300 mg/g, those who attained at least two targets had lower hazard ratios for cardiorenal events [0.61 (0.39-0.96)], four major adverse cardiovascular events [0.53 (0.28-0.98)] and all-cause mortality [0.35 (0.17-0.70)] compared with those who failed to attain any targets.

CONCLUSIONS

These findings suggest that the attainment of a combination of nephroprotection targets is associated with better cardiorenal outcomes and a lower mortality rate in people with diabetic kidney disease.

Kidney Function Decline and Serious Adverse Drug Reactions in Patients With CKD

RATIONALE & OBJECTIVE

Adverse drug reactions (ADRs) are common in patients with chronic kidney disease (CKD). The impact of kidney function decline on serious ADR risk has been poorly investigated. We comprehensively describe ADRs and assess the relationship between estimated glomerular filtration rate (eGFR) and serious ADR risk.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

3,033 participants in French Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort study, a nationwide sample of nephrology outpatients with moderate to advanced CKD.

PREDICTORS

Demographic and biological data (including eGFR), medication prescriptions.

OUTCOME

ADRs (preventable or not) were prospectively identified from hospital discharge reports, medical records, and patient interviews. Expert pharmacologists used validated tools to adjudicate ADRs.

ANALYTICAL APPROACH

Restricted cubic splines in fully adjusted cause-specific Cox proportional hazard models were used to evaluate the relationship between eGFR and the risk of serious ADRs (overall and by subtype).

RESULTS

During a median follow-up period of 4.7 years, 360 patients experienced 488 serious ADRs. Kidney and urinary disorders (n=170) and hemorrhage (n=170) accounted for 70% of serious ADRs. The most common medications classes were antithrombotics and renin-angiotensin system inhibitors. The majority of those serious ADRs were associated with hospitalization (n=467), with 32 directly or indirectly associated with death and 22 associated with a life-threatening event. More than 27% of the 488 serious ADRs were preventable or potentially preventable. The eGFR is a major risk factor for serious ADRs. The risk of acute kidney injury was 2.2% higher and risk of bleeding ADRs was 8% higher for each 1mL/min/1.73m2 lower baseline eGFR.

LIMITATIONS

The results cannot be extrapolated to patients who are not being treated by a nephrologist.

CONCLUSIONS

ADRs constitute a major cause of hospitalization in CKD patients for whom lower eGFR level is a major risk factor.

PLAIN-LANGUAGE SUMMARY

Patients with chronic kidney disease (CKD) have complex clinical presentations, take multiple medications, and often receive inappropriate prescriptions. Using data from a large, prospective CKD cohort, we found a high incidence of serious adverse drug reactions (ADRs). The 2 most common serious ADRs were drug-induced acute kidney injury and bleeding. A large proportion of serious ADRs required hospital admission, and 11% led to death or were life threatening. Lower kidney function was a major risk factor for serious ADRs. Many of these serious ADRs were determined to be partly preventable through greater adherence to prescription guidelines. This report enhances our understanding of the potential toxicity of drugs taken by patients with moderate to advanced CKD. It emphasizes the importance of monitoring kidney function when prescribing drugs, particularly for high-risk medications such as antithrombotic agents.

Haemoglobin trajectories in chronic kidney disease and risk of major adverse cardiovascular events

BACKGROUND

The trajectories of haemoglobin in patients with chronic kidney disease (CKD) have been poorly described. In such patients, we aimed to identify typical haemoglobin trajectory profiles and estimate their risks of major adverse cardiovascular events (MACE).

METHODS

We used 5-year longitudinal data from the CKD-REIN cohort patients with moderate to severe CKD enrolled from 40 nationally representative nephrology clinics in France. A joint latent class model was used to estimate, in different classes of haemoglobin trajectory, the competing risks of (i) MACE + defined as the first event among cardiovascular death, non-fatal myocardial infarction, stroke or hospitalization for acute heart failure, (ii) initiation of kidney replacement therapy (KRT) and (iii) non-cardiovascular death.

RESULTS

During the follow-up, we gathered 33 874 haemoglobin measurements from 3011 subjects (median, 10 per patient). We identified five distinct haemoglobin trajectory profiles. The predominant profile (n = 1885, 62.6%) showed an overall stable trajectory and low risks of events. The four other profiles had nonlinear declining trajectories: early strong decline (n = 257, 8.5%), late strong decline (n = 75, 2.5%), early moderate decline (n = 356, 11.8%) and late moderate decline (n = 438, 14.6%). The four profiles had different risks of MACE, while the risks of KRT and non-cardiovascular death consistently increased from the haemoglobin decline.

CONCLUSION

In this study, we observed that two-thirds of patients had a stable haemoglobin trajectory and low risks of adverse events. The other third had a nonlinear trajectory declining at different rates, with increased risks of events. Better attention should be paid to dynamic changes of haemoglobin in CKD.

Factors associated with changes in echocardiographic parameters following kidney transplantation

BACKGROUND

Chronic kidney disease leads to cardiac remodelling of multifactorial origin known as "uraemic cardiomyopathy", the reversibility of which after kidney transplantation (KT) remains controversial. Our objectives were to assess, in the modern era, changes in echocardiographic parameters following KT and identify predictive clinical and biological factors associated with echocardiographic changes.

METHODS

One hundred six patients (mean age 48 ± 16, 73% male) who underwent KT at the University Hospital of Nancy between 2007 and 2018 were retrospectively investigated. Pre- and post-KT echocardiography findings (8.6 months before and 22 months after KT on average, respectively) were centralised, blind-reviewed and compared.

RESULTS

A majority of patients (60%) had either a left ventricular (LV) ejection fraction < 50%, at least moderately abnormal LV mass index or left atrial (LA) dilatation at pretransplanted echocardiography. After KT, LV remodelling and diastolic doppler indices did not significantly change whereas LA volume index (LAVI) increased (35.9 mL/m2 post-KT vs. 30.9 mL/m2 pre-KT, p = 0.006). Advancing age, cardiac valvular disease, delayed graft function, lower post-KT haemoglobin, and more severe post-KT hypertension were associated with higher LAVI after KT. Higher post-KT serum creatinine, more severe post-KT hypertension and lower pre-KT blood calcium levels were associated with a deterioration in LAVI after KT.

DISCUSSION/CONCLUSION

Adverse remodelling of the left atrial volume occurred after KT, predominantly in patients with lower pre-KT blood calcium, poorer graft function and post-KT hypertension. These results suggest that a better management of modifiable factors such as pre-KT hyperparathyroidism or post-KT hypertension could limit post-KT cardiac remodelling.

Quality-of-life measures and their psychometric properties used in African chronic kidney disease populations: a systematic review using COSMIN methodology

BACKGROUND

If any benefit is to be derived from the use of the health-related quality of life (HRQoL) questionnaires in chronic kidney disease (CKD) patients, they should be validated and culturally adapted to the target population. We aimed to critically appraise the psychometric properties of HRQoL questionnaires used in African populations with CKD.

METHODS

Web of Science, Embase, PubMed and PsycINFO databases were searched. Psychometric validation studies of HRQoL questionnaires reporting at least one psychometric property of the COSMIN checklist in CKD African population, published up to October 16, 2023 were included and independently assessed for methodological quality and level of measurement properties by using the COSMIN methodology.

RESULTS

From 1163 articles, 5 full-text were included. Only the Kidney Disease Quality-of-Life questionnaire was translated and cross-culturally adapted for studies of patients with CKD. Internal consistency was of doubtful quality in 4 studies and very good in 1. Its measurement was sufficient in 1 study and insufficient in 4. Test-retest reliability was of doubtful quality in 4 studies. Its measurement was sufficient in 3 studies and insufficient in 1. Structural validity was of inadequate quality in 1 study and very good quality in 1. Its measurement was sufficient in both. Construct validity was of inadequate quality in all studies. Their measurement was insufficient in 4 studies and sufficient in 1.

CONCLUSIONS

This review highlighted that only one HRQoL questionnaire used in studies of African populations with CKD underwent a small number of cultural adaptations and psychometric validations, generally of poor methodological quality. HRQoL validation studies in African CKD populations are needed to better take advantage of the benefits in patient care, population health management, and research.

Study of the association between serum levels of kynurenine and cardiovascular outcomes and overall mortality in chronic kidney disease

Background

Kynurenine is a protein-bound uremic toxin. Its circulating levels are increased in chronic kidney disease (CKD). Experimental studies showed that it exerted deleterious cardiovascular effects. We sought to evaluate an association between serum kynurenine levels and adverse fatal or nonfatal cardiovascular events and all-cause mortality in CKD patients.

Methods

The CKD-REIN study is a prospective cohort of people with CKD having an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m². Baseline frozen samples of total and free fractions of kynurenine and tryptophan were measured using a validated liquid chromatography tandem mass spectrometry technique. Cause-specific Cox models were used to estimate hazard ratios (HRs) for each outcome.

Results

Of the 2406 included patients (median age: 68 years; median eGFR: 25 ml/min/1.73 m2), 52% had a history of cardiovascular disease. A doubling of serum-free kynurenine levels was associated with an 18% increased hazard of cardiovascular events [466 events, HR (95%CI):1.18(1.02,1.33)], independently of eGFR, serum-free tryptophan level or other uremic toxins, cardioprotective drugs, and traditional cardiovascular risk factors. Serum-free kynurenine was significantly associated with non-atheromatous cardiovascular events [HR(95%CI):1.26(1.03,1.50)], but not with atheromatous cardiovascular events [HR(95%CI):1.15(0.89,1.50)]. The association of serum-free kynurenine with cardiovascular mortality was also independently significant [87 events; adjusted HR(95%CI):1.64(1.10,2.40)]. However, the association of serum-free kynurenine with all-cause mortality was no more significant after adjustment on serum-free tryptophan [311 events, HR(95%CI):1.12(0.90, 1.40)].

Conclusions

Our findings imply that serum-free kynurenine, independently of other cardiovascular risk factors (including eGFR), is associated with fatal or nonfatal cardiovascular outcomes, particularly non-atheromatous cardiovascular events; in patients with CKD. Strategies to reduce serum kynurenine levels should be evaluated in further studies.

Evolution of HLA-sensitization according to immunosuppressive therapy management among kidney transplant patients returning to dialysis between 2008 and 2019: A French retrospective study

BACKGROUND

The optimal management of immunosuppressive therapy (IT) after kidney allograft failure (KAF) remains controversial. Although maintaining IT may reduce HLA-sensitization and improve access to retransplantation, it may also increase the rate of immunosuppression-related complications. The overall impact on patient mortality is unknown. The main objective of this study was to compare the evolution of HLA-sensitization 6 months after KAF according to IT management.

METHODS

Individual clinical and health care data were extracted from the French national end-stage kidney disease registry (Renal Epidemiology and Information Network [REIN]) and the French National Health Data system (SNDS), respectively. Patients aged > 18 years returning to dialysis after KAF between January 2008 and December 2019 in Lorraine were included. Patients were classified into two groups, IT continuation or IT discontinuation. HLA-sensitization was defined as an increase in incompatible graft rate (IGR) between KAF and 6 months post-KAF (change to a higher predefined category (0%-5%), (5%-20%), (20%-50%), (50%-85%), (85%-95%), (95%-98%), (98%-100%)). Secondary outcome was patient survival according to IT management.

RESULTS

A total of 121 patients were included, 35 (29%) of whom continued IT. HLA-sensitization after KAF tended to be higher in the "IT discontinuation" group (57% vs. 38% in the "IT continuation" group, p = .07). In multivariate analysis, IT continuation was associated with a lower increase in IGR (OR .37, 95% CI [.14; .93]). IT management was not associated with patient mortality.

CONCLUSIONS

Continuation of IT after KAF was associated with less change in IGR and was not associated with excess mortality.

A New Approach for Cognitive Impairment Pattern in Chronic Kidney Disease

BACKGROUND AND HYPOTHESIS

Chronic kidney disease (CKD) is associated with an elevated risk of neurocognitive disorders (NCDs). It remains unclear whether CKD-related NCDs have specific cognitive pattern or are earlier-onset phenotypes of the main NCDs (vascular NCDs and Alzheimer's disease).

METHODS

We used the Mini Mental State Examination score (MMSE) to assess cognitive pattern in 3003 CKD patients (stage 3 to 4) followed up over 5 years in the Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort. After normalizing MMSE scores to a 0-to-100 scale, the associations between the baseline estimated glomerular filtration rate (eGFR, using the CKD-EPI-creatinine formula) and changes in each MMSE domain score were assessed in linear mixed models.

RESULTS

Patients (age: 67±13 years old; males: 65%, mean eGFR: 33±12 ml/min/1.73 m²) had a good baseline cognitive functions: the mean MMSE score was 26.9/30 ±2.9. After adjustment for age, sex, educational level, depression (past or present), cardiovascular risk factors, cerebrovascular disease, a lower baseline eGFR (per 10 ml/min/1.73 m²) was associated with a 0.53-point decrement (p<0.001; 95%CI [-0.98,-0.08]) for orientation, a 1.04-point decrement (p=0.03; 95%CI [-1.96,-0.13]) for attention and calculation, a 0.78-point decrement (p=0.003; 95%CI [-1.30,-0.27]) for language, and a 0.94-point decrement (p=0.02; 95%CI [-1.75,-0.13]) for praxis. Baseline eGFR was not, however, associated with significant changes over time in MMSE domain scores.

CONCLUSION

A lower eGFR in CKD patients was associated with early impairments in certain cognitive domains: praxis, language and attention domains before an obvious cognitive decline. Early detection of NCD in CKD patients must be perform before clinically cognitive decline using preferably tests assessing executive, attentional functions and language than memory test. This could lead to a better management of cognitive impairment and their consequences on CKD management.

Comprehensive conservative care: what doctors say, what patients hear

The demographic evolution of patients with advanced chronic kidney disease (CKD) has led to the advent of an alternative treatment option to kidney replacement therapy in the past couple of decades. The KDIGO controversies on Kidney Supportive Care called this approach "comprehensive conservative care" (CCC) and defined it as planned holistic patient-centered care for patients with CKD stage 5 that does not include dialysis. Although the benefit of this treatment option is now well-recognized, especially for the elderly, and comorbid and frail patients, its development remains limited in practice. While shared decision-making and advance care planning represent the cornerstones of the CCC approach, one of the main barriers in its development is the perfectible communication between nephrologists and patients, but also between all healthcare professionals involved in the care of advanced CKD patients. As a result, a significant gap has opened up between what doctors say and what patients hear. Indeed, although CCC is reported by nephrologists to be widely available in their facilities, few of their patients say that they have actually heard of it. The objectives of this review are to explore discrepancies between what doctors say and what patients hear, to identify the factors underlying this gap, and to formulate practical proposals for narrowing this gap in practice.

Chronic kidney disease and nephrological practices in France: lessons from the CKD-REIN cohort, 2013-2023

Launched in 2013 supported by the Program “Cohorts – Investments for the Future”, the CKD-REIN (Chronic Kidney Disease – Renal Epidemiology and Information Network) study is a prospective cohort that included and followed for 5 years more than 3000 patients with moderate or advanced chronic kidney disease (CKD), from 40 nationally representative nephrology clinics. A large amount of data was collected on CKD and its treatments, patient social characteristics and reported outcomes, and nephrology practices and services. A total of 170,000 blood and urine samples were collected and stored in a central biobank. Coordinated with the CKD outcomes and practice pattern study (CKDopps) and collaborating with the international Network of CKD cohorts (iNETCKD), CKD-REIN contributes to the understanding of CKD and the positioning of France with respect to CKD epidemiology and care in the world. This review highlights major findings from the cohort, and their potential implications for clinical practices and the health system, grouped into the following themes: (1) the complexity of patients with CKD; (2) adherence to clinical guidelines; (3) treatment practices and drug risk; (4) acute on chronic kidney disease; (5) CKD metabolic complications; (6) prediction of kidney failure; (7) sex differences in CKD; (8) patient perspective on CKD; (9) transition to kidney failure and replacement therapy; (10) conservative care.

Proton-Pump Inhibitors and Serum Concentrations of Uremic Toxins in Patients with Chronic Kidney Disease

Use of proton-pump inhibitors (PPIs) is common in patients with chronic kidney disease (CKD). PPIs and many uremic toxins (UTs) are eliminated by the kidney's tubular organic anion transporter system. In a cross-sectional study, we sought to evaluate the association between PPI prescription and serum concentrations of various UTs. We studied a randomly selected sub-group of participants in the CKD-REIN cohort (adult patients with a confirmed diagnosis of CKD and estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m²) with available frozen samples collected at baseline. PPI prescription was recorded at baseline. Serum concentrations of 10 UTs were measured using a validated liquid chromatography tandem mass spectrometry technique. Multiple linear regression was performed, with the log UT concentration as the dependent variable. Of the 680 included patients (median age: 68 years; median eGFR: 32 mL/min/1.73 m²), 31% had PPI prescriptions at baseline. Patients using PPIs had higher levels of certain UTs in comparison to other patients, including total and free indoxyl sulfate (IS), total and free p-cresylsulfate, total and free p-cresylglucuronide (PCG), phenylacetylglutamine (PAG), free kynurenine, and free hippuric acid. After adjustment for baseline co-morbidities, number of co-prescribed drugs, and laboratory data, including eGFR, associations between PPI prescription and elevated serum concentrations of free and total IS, free and total PCG, and PAG remained significant. Our results indicate that PPI prescription is independently associated with serum UT retention. These findings are interesting to better understand the factors that may modulate serum UT concentration in CKD patients, however, they will need to be confirmed by longitudinal studies.

Levels of Procollagen Type I C-Terminal Pro-Peptide and Galectin-3, Arterial Stiffness Measured By Pulse Wave Velocity, and Cardiovascular Morbidity and Mortality in 44 Patients 2 Years After Kidney Transplantation

BACKGROUND Cardiovascular (CV) mortality remains high despite the improvement of kidney function after kidney transplantation. In heart failure (HF), high concentrations of biomarkers of fibrosis, related to cardiac and/or vascular impairment, are associated with CV outcomes, but their significance in kidney transplantation is still unclear. Our aim was to investigate the association of procollagen type I C-terminal pro-peptide (PICP) and galectin-3 (Gal-3), markers of fibrosis, with arterial stiffness measured by pulse wave velocity (PWV) and CV morbi-mortality in kidney transplantation recipients from the prospective monocenter TRANSARTE study (Transplantation and Arteries), which compared the evolution of arterial stiffness in transplanted patients and patients remained on dialysis. MATERIAL AND METHODS PICP and Gal-3 were measured at 2 years after transplantation in 44 kidney transplantation patients. Spearman's rank-order correlation analysis was conducted to assess the relationship between biomarkers and PWV. Association of biomarkers with CV morbi-mortality was evaluated using Cox regression analysis adjusted for age, renal function, and PWV. RESULTS There was no significant correlation between PWV and PICP (r=-0.16, P=0.3) or Gal-3 (r=0.03, P=0.85). Gal-3, after adjusting for key prognostic factors, including PWV, was significantly associated with CV morbi-mortality [HR (95% CI)=4.30 (1.01-18.22), P=0.048], whereas PICP was not significantly associated with outcome. CONCLUSIONS In multivariable adjusted analysis, elevated Gal-3 concentrations were associated with CV morbi-mortality in kidney transplantation patients, whereas PICP was not. As Gal-3 was not related to PWV, other sources of fibrosis (eg, cardiac fibrosis) may be underlying the prognostic value of Gal-3 in kidney transplantation.

Cognitive performance is associated with glomerular filtration rate in patients with chronic kidney disease: results from the CKD-REIN cohort

BACKGROUND

Chronic kidney disease (CKD) is associated with cognitive impairment in general population. We assessed the association between kidney and cognitive functions in patients with CKD and the influence of cardiovascular (CV) risk factors, and depression on this association.

METHODS

The CKD-Renal Epidemiology and Information Network cohort included 3033 patients with CKD stages 3-4, followed for 5 years. Cognitive function was assessed with the Mini-Mental State Examination (MMSE) and estimated glomerular filtration rate (eGFR) with the CKD-Epidemiology Collaboration equation-creatinin formula. Evolution of the MMSE score over time and its association with baseline eGFR were investigated with linear mixed models. We assessed the risk of incident cognitive outcome (hospitalisation or death with relevant International Classification of Disease-10 codes), with a Cox proportional hazard model.

RESULTS

The mean age was 66.8, the mean eGFR was 33 mL/min/1.73 m² and 387 patients (13.0%) had an MMSE score below 24 at baseline. A 10 mL/min/1.73 m² decrement of baseline eGFR was associated with a mean MMSE decrease of 0.12 (95% CI 0.04 to 0.19) after adjustment for demographic characteristics, depression, CV risk factors and disease; but baseline eGFR was not associated with MMSE temporal evolution. HR for cognitive outcome during follow-up (median 2.01 years) associated with a 10 mL/min/1.73 m² decrement of baseline eGFR was 1.35 (1.07, 1.70) (p=0.01) after adjustment.

CONCLUSIONS

In patients with CKD, lower eGFR was associated with worse cognitive performance and incident cognitive events, independently of demographics, CV risk factors and depression.

TRIAL REGISTRATION NUMBER

NCT03381950.

Factors influencing kidney transplantation rates: a study from the ERA Registry

BACKGROUND

Large international differences exist in kidney transplantation (KT) rates. We aimed to investigate which factors may explain the total, deceased donor, and living donor KT rates over the last decade.

METHODS

KT experts from 39 European countries completed the Kidney Transplantation Rate Survey on measures and barriers and their potential effect on the KT rate in their country. In the analyses, countries were divided into low, middle, and high KT rate countries based on the KT rate at the start of study period in 2010.

RESULTS

Experts from low KT rate countries reported more frequently to have taken measures regarding staff, equipment and facilities to increase total KT rate compared with middle and high KT rate countries. For donor type specific KT, the largest international differences in measures taken were reported for deceased donor KT, with middle and high KT rate countries taking more measures, such as the use of expanded criteria donor kidneys, the presence of transplantation coordinators, and (inter)national exchange of donor kidneys. Once a measure was taken, experts' opinion on its success was similar across the low, middle and high KT rate countries. Experts from low KT rate countries more often reported potential barriers, such as patients' lack of knowledge and distrust in the health care system.

CONCLUSIONS

In particular in low KT rate countries, KT rate might be stimulated by optimizing staff, equipment, and facilities. In addition, all countries may benefit from deceased and living donor specific measures.

Aetiology, clinical features, diagnostic studies, and outcomes of community-acquired pneumonia in kidney transplant recipients admitted to hospital: a multicentre retrospective French cohort study

OBJECTIVES

To assess the aetiology, clinical features, diagnostic studies and outcomes of community-acquired pneumonia (CAP) in a French cohort of hospitalized kidney transplant recipients.

METHODS

We performed a retrospective, multicentre study in kidney transplant recipients admitted to ten French centres for CAP from January 2016 to December 2018. CAP discharge diagnoses were clinically and radiologically validated. We assessed a descriptive analysis of all confirmed CAP including medical ward and intensive care unit admissions.

RESULTS

One hundred sixty-five CAP episodes in 132 patients were included. Median time from transplantation to admission was 6.4 (interquartile range, 1.6-12.3) years, with corticosteroid exposure in 112/165 (67.9%) cases. Sputum culture was performed in 47/165 (28.5%) cases including 7/47 (14.9%) positive samples. Bronchoscopy was performed in 87/165 (52.7%) cases with pathogens identified in 39/87 (44.8%) cases. Microbiological studies led to identifying a respiratory pathogen in 64/165 (38.8%) CAP episodes including 11/64 (17.2%) polymicrobial cases. Among these 64 episodes, 75 microorganisms were identified; 46/75 (61.3%) were core respiratory pathogens and 29/75 (38.7%) were opportunistic or drug-resistant organisms including Pneumocystis jirovecii 9/75 (12%), Pseudomonas aeruginosa 5/75 (6.7%), multidrug-resistant Enterobacteriaceae 4/75 (5.3%), and Aspergillus 4/75 (5.3%). Patients required intensive care unit admission in 26/165 (15.8%) episodes, invasive ventilation in 20/165 (12.1%) cases, and 22/165 (13.3%) needed in-hospital dialysis.

DISCUSSION

CAP episodes occurred in kidney transplant recipients with a long history of immunosuppressive drug exposure. Diagnostic studies identified a microorganism in more than one-third of CAP episodes, including drug-resistant and opportunistic pathogens.

Barriers to conservative care from patients' and nephrologists' perspectives: the CKD-REIN study

BACKGROUND

Conservative care is increasingly considered an alternative to kidney replacement therapy for kidney failure management, mostly among the elderly. We investigated its status and the barriers to its implementation from patients' and providers' perspectives.

METHODS

We analysed data from 1204 patients with advanced chronic kidney disease (CKD) [estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2] enrolled at 40 nationally representative nephrology clinics (2013-16) who completed a self-administered questionnaire about the information they received and their preferred treatment option, including conservative care, if their kidneys failed. Nephrologists (n = 137) also reported data about their clinics' resources and practices regarding conservative care.

RESULTS

All participating facilities reported they were routinely able to offer conservative care, but only 37% had written protocols and only 5% had a person or team primarily responsible for it. Overall, 6% of patients were estimated to use conservative care. Among nephrologists, 82% reported they were fairly or extremely comfortable discussing conservative care, but only 28% usually or always offered this option for older (>75 years) patients approaching kidney failure. They used various terminology for this care, with conservative management and non-dialysis care mentioned most often. Among patients, 5% of those >75 years reported receiving information about this option and 2% preferring it.

CONCLUSIONS

Although reported by nephrologists to be widely available and easily discussed, conservative care is only occasionally offered to older patients, most of whom report they were not informed of this option. The lack of a person or team responsible for conservative care and unclear information appear to be key barriers to its implementation.

Five-Year Symptom Trajectories in Nondialysis-Dependent CKD Patients

BACKGROUND AND OBJECTIVES

Late stages of CKD are characterized by significant symptom burden. This study aimed to identify subgroups within the 5-year trajectories of symptom evolution in patients with CKD and to describe associated patient characteristics and outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Among 2787 participants (66% men) with eGFR <60 ml/min per 1.73 m2 enrolled in the CKD-Renal Epidemiology and Information Network (CKD-REIN) cohort study from July 2013 to May 2016, we assessed symptoms annually using the Kidney Disease Quality of Life-36 (KDQOL-36) questionnaire until December 2020. A total of 9121 measures were reported over follow-up; all participants had symptoms scored for at least one time point. We used a joint latent class-mixed model to distinguish profiles of symptom trajectories.

RESULTS

Patient mean age (±SD) at baseline was 67±13 years, and mean eGFR was 33±13 ml/min per 1.73 m2. The prevalence of each symptom ranged from 24% (chest pain) to 83% (fatigue), and 98% of participants reported at least one symptom. After a median (interquartile range) follow-up of 5.3 (3.4-6.0) years, 690 participants initiated KRT, and 490 died before KRT. We identified two profiles of symptom trajectories: a "worse symptom score and worsening trajectory" in 31% of participants, characterized by a low initial symptom score that worsened more than ten points over time, and a "better symptom score and stable trajectory" in 69% of participants, characterized by a high initial score that remained stable. Participants in the worse symptom score and worsening trajectory group had more risk factors for CKD progression at baseline, worse quality of life, and a higher risk of KRT and death before KRT than other participants.

CONCLUSIONS

This study highlights a significant worsening of symptoms in about one third of the participants, whereas the majority reported low symptom severity throughout the study.

Absence of Mortality Differences Between the First and Second COVID-19 Waves in Kidney Transplant Recipients

Introduction

SARS-CoV-2 pandemic evolved in 2 consecutive waves during 2020. Improvements in the management of COVID-19 led to a reduction in mortality rates among hospitalized patients during the second wave. Whether this progress benefited kidney transplant recipients (KTRs), a population particularly vulnerable to severe COVID-19, remained unclear.

Methods

In France, 957 KTRs were hospitalized for COVID-19 in 2020 and their data were prospectively collected into the French Solid Organ Transplant (SOT) COVID registry. The presentation, management, and outcomes of the 359 KTRs diagnosed during the first wave were compared to those of the 598 of the second wave.

Results

Baseline comorbidities were similar between KTRs of the 2 waves. Maintenance immunosuppression was reduced in most patients but withdrawal of antimetabolite (73.7% vs. 58.4%, P < 0.001) or calcineurin inhibitor (32.1% vs. 16.6%, P < 0.001) was less frequent during the second wave. Hydroxychloroquine and azithromycin that were commonly used during the first wave (21.7% and 30.9%, respectively) but were almost abandoned during the second wave. In contrast, the use of high dose corticosteroids doubled (19.5% vs. 41.6%, P < 0.001). Despite these changing trends in COVID-19 management, 60-day mortality was not statistically different between the 2 waves (25.3% vs. 23.9%; Log Rank, P = 0.48) and COVID-19 hospitalization period was not associated with death due to COVID-19 in multivariate analysis (Hazard ratio 0.89, 95% confidence interval 0.67–1.17, P = 0.4).

Conclusion

We conclude that changing of therapeutic trends during 2020 did not reduce COVID-19 related mortality among KTRs. Our data indirectly support the importance of vaccination and neutralizing monoclonal anti-SARS-CoV-2 antibodies to protect KTRS from severe COVID-19.

Association between kidney retransplantation and survival according to age in the French national cohort of dialysis patients

The mean age of patients returning to dialysis after a first kidney transplantation (KT) has increased in the past decades. We aimed to assess the association between second KT (2KT) and survival according to age at the time of return to dialysis. Data of 5334 patients registered in the French Renal Epidemiology and Information Network (REIN) (mean age 56.6 ± 13.6 years) who returned to dialysis after a first KT were collected. The association of 2KT with death was assessed using a propensity score-based analysis taking into account baseline and follow-up variables. In relisted patients (3272 patients, 61.3%), retransplantation was associated with better overall survival in comparison with patients who remained in dialysis (adjusted HR 0.75 [0.63-0.89], p = .0009). The survival advantage conferred by retransplantation gradually declined with increasing age (adjusted HR 0.41 [0.24-0.70] in patients <50, HR 0.94 (0.69-1.27) in patients aged 70 or older, p for interaction 0.034 for age considered as a continuous variable). 2KT is associated with better survival as opposed to remaining on dialysis after a first kidney graft failure. Nevertheless, this survival benefit is age dependent and diminishes with increasing age. The risk/benefit ratio should be comprehensively assessed in the oldest patients when relisting is considered.

[Nephrologist-IPA collaboration for better patient management]

Chronic kidney disease, the extreme consequence of which is dialysis or transplantation, requires a highly structured care pathway, marked by precise care and treatment recommendations. Given the aging of the population, the increase in the number of patients is inevitable. Synergy between nephrologists and advanced practice nurses allows the implementation of organization protocols in fields of competence including consultations and prescriptions.

Lack of Monitoring Is Associated with Risk of Acute Kidney Events among Patients with Inflammatory Bowel Disease

Background: Although the iatrogenic risk of kidney failure is infrequent with treatment for inflammatory bowel disease (IBD), the repercussions for the patient could be major. The aim of this study was to assess the incidence of kidney events in IBD and to examine the protective effect of kidney function monitoring. Methods: In the French National Health Insurance database, 94,363 patients had a diagnosis of IBD between January 2010 and December 2016. By using a survival model with time-dependent covariates, we analyzed the time from inclusion in this IBD cohort to the first hospitalization for acute kidney impairment (AKI) according to patient characteristics, comorbidities, IBD phenotype and presence of monitoring. Results: A total of 693 patients were hospitalized for AKI, with an incidence of 1.36/1000 person−years (95% confidence interval [CI] 1.26−1.47). The incidence of AKI was lower than those without 5-aminosalicylic acid (5-ASA) use. Patients with 5-ASA use rarely had any lack of monitoring as compared with those not under 5-ASA use (3% vs. 17%). On multivariate analysis, lack of monitoring was associated with a substantial risk of AKI (hazard ratio 3.96, 95% CI [3.20−4.90], p < 0.0001). Conclusions: Increased frequency of monitoring is essential to identify nephropathy at an early stage and avoid the progression to chronic kidney disease.

MO503: Cognitive Performance in Patients With Chronic Kidney Disease: Results From the CKD-Rein Cohort Study

BACKGROUND AND AIMS

Chronic kidney disease (CKD) is a risk factor for cognitive impairment. In the general population, many risk factors have been reported in association with incident major neurocognitive disorders. The link between CKD and cognitive dysfunction is not completely understood; it may involve different mechanisms such as vascular dysfunction or uremic toxin toxicity. We aimed to assess the influence of cardiovascular risk factors, cardiovascular disease and depression on the association between kidney function and cognitive function in patients with CKD.

METHOD

We analyzed baseline data from 3033 patients with CKD stage 3–5 included in the Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort between 2013 and 2016. Cognitive function was assessed with the Mini Mental State Examination (MMSE), and the glomerular filtration rate was estimated with the CKD EPI formula. We applied unadjusted and adjusted linear and logistic regression models, with the MMSE score as a continuous or categorical variable (at a cut-off point at 24/30).

RESULTS

The mean patient age was 66.8, the mean estimated glomerular filtration rate (eGFR) was 33 mL/min/1.73 m2 and 393 patients (13.0%) had a MMSE score &lt;24. We observed that, relative to patients with an MMSE score of 24 or more, patients with a score &lt;24 were older and more likely to be female and dependent on activities of daily living (ADL) and/or instrumental ADL. They were taking more medications and they were more affected by depressive symptoms as measured by the CES-D-10 (10 item Centre for Epidemiological Studies-Depression scale). Patients with a score &lt;24 were also more likely to present cardiovascular (CV) risk factors and CV comorbidities. They had a significantly higher parathyroid hormone level, lower haemoglobin, lower albumin and lower eGFR.

The eGFR was positively associated with the MMSE score before and after adjustment for age, sex, education level, cardiovascular risk factors, cardiovascular disease and depression, giving point increases in the MMSE score of 0.24 (0.15–0.33; P &lt; .001) and 0.14 (0.04–0.23; P = .006) for a 10 mL/min/1.73 m2 increment in the eGFR, respectively. Other risk factors significantly associated with a lower MMSE score in multivariate analysis were age, female sex, lower educational level, diabetes, obesity, cerebrovascular disease, atrial fibrillation and CES-D-10 score. The eGFR was associated with a low MMSE score (defined as MMSE score &lt;24/30) with a crude odds ratio (OR) of 0.82 (0.75–0.90), which remained significant at 0.88 (0.78–0.98) after adjustment for age, sex, educational level, cardiovascular risk factors (hypertension, diabetes mellitus, dyslipidaemia, obesity and smoking), cardiovascular comorbidities (cerebrovascular disease, atrial fibrillation and heart failure), history of depression, laboratory parameters (haemoglobin and phosphate) and CES-D score (after imputation of missing values).

CONCLUSION

In a cohort of well-phenotyped patients with CKD, lower eGFR is associated with worse cognitive function, independent of age, sex, educational level, cardiovascular injury and depression.

MO496: Serum Urea Levels and Cardiovascular Disease in Patients With Chronic Kidney Disease

BACKGROUND AND AIMS

Elevated serum urea levels are common in moderate-to-advanced CKD. Several studies have shown that urea is a direct and indirect uremic toxin, especially with regard to cardiovascular disease. We sought to determine whether serum urea levels are associated with adverse cardiovascular events and death before kidney replacement therapy (KRT) in patients with CKD.

METHOD

CKD-REIN is a prospective cohort of CKD nephrology outpatients not receiving maintenance dialysis. The 2507 patients included in the analysis were divided into three groups according to the baseline serum urea level (T1 &lt; 10.5, T2:10.5–15.1 and T3 ≥ 15.1 mmol/L). Cause-specific Cox proportional hazard models were used to estimate hazard ratios (HRs) for the first atheromatous or nonatheromatous cardiovascular (CV) events and all-cause mortality before KRT. The models were adjusted for baseline comorbidities, laboratory data, and medications. Cardiovascular events of the first 3 years of follow-up in the CKD-REIN study were assessed carefully according to the Cardiovascular and Stroke Endpoint Definitions for Clinical Trials. Each death before KRT occurring during the 5-year follow-up period was used in the all-cause mortality model.

RESULTS

Of the 2507 included patients {median [first quartile–third quartile (Q1–Q3)] age: 69 (61–77); mean (standard deviation) eGFR 33.5(11.6) mL/min/1.73 m²}, 54% had a history of cardiovascular disease.

Over a median follow-up of 3.0 years [Q1–Q3, 2.2–3.1], 451 experienced their first atheromatous or nonatheromatous cardiovascular event (fatal or nonfatal), leading to an incidence rate (IR) [95% confidence interval (95% CI)] of 7.1 (6.4–7.7)/100 person-years (PYs) (Fig. 1).

Over a median follow-up period of 4.8 (3.3–5.1) years, 407 patients died before KRT, leading to an IR of 4.0 (3.6–4.3)/100 PYs.

After multiple adjustments for cardiovascular risk factors (including eGFR), patients in T3 had a higher risk of atheromatous and nonatheromatous cardiovascular events than patients in T1 [HR (95% CI), 2.08 (1.50–2.88), Fig. 1]. A nonsignificant trend towards a higher risk was also noted for patients in T2 [1.28 (0.96–1.71)]. The adjusted HRs for death before KRT were 1.30 (0.96–1.75] and 1.73 (1.22–2.45) for patients in T2 and those in T3, respectively.

CONCLUSION

Beyond CV risk factors including eGFR, this hypothesis-generating study suggests that serum urea level is a predictor of cardiovascular outcomes in patients with moderate to advanced CKD. Further research is needed to confirm current findings and explore mechanisms.

MO499: Incidence of Cause-Specific Cardiovascular Events in Men and Women With CKD

BACKGROUND AND AIMS

Men are at higher risk of cardiovascular disease (CVD) than women in the general population, and chronic kidney disease (CKD) is a well-established cardiovascular (CV) risk factor [1–4]. However, the incidence of cause-specific CV events in men and women with CKD is poorly documented.

METHOD

All hospitalization and death reports for CV events of the 3033 patients (1983 men and 1050 women) with non-dialysis CKD (stage 3–5) included in the French CKD-REIN Cohort were reviewed and classified by cause using criteria from the Cardiovascular and Stroke Endpoint Definitions for Clinical Trials [5]. Cause-specific Cox proportional hazard models were used to estimate hazard ratios for death and each fatal or nonfatal CV event according to gender.

RESULTS

At baseline, in men (mean age: 68 years; mean eGFR 33 mL/min/1.73 m²), the prevalence of atheromatous CVD was 30% for coronary artery disease, 14% for cerebrovascular disease and 17% for lower limb artery disease, and that of non-atheromatous CVD was 14% for heart failure and 13% for atrial fibrillation. In women (65 years old, 32 mL/min/1.73 m²), these prevalences were 15%, 7%, 9%, 11% and 9%, respectively.

During a median follow-up of 5 (IQR: 3–5) years, 98 men and 43 women died from CVD {i.e. 1.3 [95% confidence interval (95% CI): 1.0–1.5] versus 1.0 (0.7–1.3)/100 person-years}, including 53% versus 46% from heart failure, 31% versus 19% from sudden death, and 16% versus 35% from other cardiovascular causes, respectively.

Crude incidence rates of death or hospitalization for coronary artery disease and lower limb artery disease were higher in men than in women, slightly higher for CV death, cerebrovascular disease and atrial fibrillation, but similar for both genders for heart failure (Fig. 1). History of CVD was strongly associated with subsequent CV events of any type.

In multivariable analyses, gender was no longer associated with any cause-specific CV event, whereas a lower eGFR was significantly associated with an increased risk of coronary artery disease and heart failure, but not with other CV events (Table 1).

CONCLUSION

In patients with moderate or advanced CKD, the burden of atheromatous CVD is higher in men than in women and explained by their higher prevalence of cardiovascular risk factors, but that for heart failure and atrial fibrillation appears to be similar for both genders.

Probiotic Intake and Inflammation in Patients With Chronic Kidney Disease: An Analysis of the CKD-REIN Cohort

Background and Aims

Little is known about the effects of probiotics on inflammation in the context of chronic kidney disease (CKD). We investigated the association between probiotic intake and inflammation in patients with moderate-to-advanced CKD.

Methods

We performed a cross-sectional study of 888 patients with stage 3–5 CKD and data on serum C-reactive protein (CRP) levels and a concomitant food frequency questionnaire. We estimated the odds ratios (ORs) [95% confidence interval (CI)] for various CRP thresholds (>3, >4, >5, >6, and >7 mg/L) associated with three intake categories (no yoghurt, ordinary yoghurt, and probiotics from yoghurts or dietary supplements) and two frequency categories (daily or less than daily).

Results

The 888 study participants (median age: 70; men: 65%) had a median estimated glomerular filtration rate of 28.6 mL/min/1.73 m² and a median [interquartile range] CRP level of 3.0 [1.6, 7.0] mg/L. Fifty-seven percent consumed ordinary yoghurt and 30% consumed probiotic yoghurt. The median intake frequency for yoghurt and probiotics was 7 per week. Relative to participants not consuming yoghurt, the ORs [95% CI] for CRP > 6 or >7 mg/L were significantly lower for participants consuming ordinary yoghurt (0.58 [0.37, 0.93] and 0.57 [0.35, 0.91], respectively) and for participants consuming probiotics (0.54 [0.33, 0.9] and 0.48 [0.28, 0.81], respectively), independently of age, sex, body mass index, CKD stage, cardiovascular disease, and fibre, protein and total energy intakes. The ORs were not significantly lower for CRP thresholds >3, >4, and >5 mg/L and were not significantly greater in daily consumers than in occasional consumers.

Conclusion

We observed independent associations between the consumption of yoghurt or probiotics and lower levels of inflammation in patients with CKD. There was no evidence of a dose-effect relationship.

Clinical Trial Registration

[https://www.clinicaltrials.gov/ct2/show/NCT03381950], identifier [NCT03381950].

Impact of targeted hypothermia in expanded-criteria organ donors on recipient kidney-graft function: study protocol for a multicentre randomised controlled trial (HYPOREME)

INTRODUCTION

Expanded-criteria donors (ECDs) are used to reduce the shortage of kidneys for transplantation. However, kidneys from ECDs are associated with an increased risk of delayed graft function (DGF), a risk factor for allograft loss and mortality. HYPOREME will be a multicentre randomised controlled trial (RCT) comparing targeted hypothermia to normothermia in ECDs, in a country where the use of machine perfusion for organ storage is the standard of care. We hypothesise that hypothermia will decrease the incidence of DGF.

METHODS AND ANALYSIS

HYPOREME is a multicentre RCT comparing the effect on kidney function in recipients of targeted hypothermia (34°C-35°C) and normothermia (36.5°C-37.5°C) in the ECDs. The temperature intervention starts from randomisation and is maintained until aortic clamping in the operating room. We aim to enrol 289 ECDs in order to analyse the kidney function of 516 recipients in the 53 participating centres. The primary outcome is the occurrence of DGF in kidney recipients, defined as a requirement for renal replacement therapy within 7 days after transplantation (not counting a single session for hyperkalemia during the first 24 hours). Secondary outcomes include the proportion of patients with individual organs transplanted in each group; the number of organs transplanted from each ECD and the vital status and kidney function of the recipients 7 days, 28 days, 3 months and 1 year after transplantation. An interim analysis is planned after the enrolment of 258 kidney recipients.

ETHICS AND DISSEMINATION

The trial was approved by the ethics committee of the French Intensive Care Society (CE-SRLF-16-07) on 26 April 2016 and by the competent French authorities on 20 April 2016 (Comité de Protection des Personnes-TOURS-Région Centre-Ouest 1, registration #2016-S3). Findings will be published in peer-reviewed journals and presented during national and international scientific meetings.

TRIAL REGISTRATION NUMBER

NCT03098706.

Urea levels and cardiovascular disease in patients with chronic kidney disease

BACKGROUND

Elevated serum urea levels are common in moderate-to-advanced CKD. Several studies have shown that urea is a direct and indirect uremic toxin, especially with regard to cardiovascular disease. We sought to determine whether serum urea levels are associated with adverse cardiovascular events and death before renal replacement therapy (RRT) in patients with CKD.

METHODS

CKD-REIN is a prospective cohort of CKD nephrology outpatients not receiving maintenance dialysis. The 2507 patients included in the analysis were divided into three groups according to the baseline serum urea level (T1 < 10.5, T2:10.5 to 15.1, and T3 ≥ 15.1 mmol/L). Cox proportional hazard models were used to estimate hazard ratios (HRs) for first atheromatous or nonatheromatous cardiovascular (CV) events, and all-cause mortality before RRT. The models were adjusted for baseline comorbidities, laboratory data, and medications.

FINDINGS

Of the 2507 included patients (median [interquartile range (IQR)] age: 69[61-77]; mean (standard deviation) eGFR 33.5(11.6) mL/min/1.73 m²), 54% had a history of cardiovascular disease. After multiple adjustments for cardiovascular risk factors (including eGFR), patients in T3 had a higher risk of atheromatous and nonatheromatous cardiovascular events than patient in T1 (n events = 451, HR[95%CI]: 1.93[1.39-2.69]). The adjusted HRs for death before RRT (n events = 407) were 1.31[0.97; 1.76] and 1.73[1.22; 2.45] for patients T2 and those in T3, respectively.

INTERPRETATION

Our data suggested that urea is a predictor of cardiovascular outcomes beyond CV risk factors including eGFR.

Effectiveness and Tolerance of Renin-Angiotensin System Inhibitors With Aging in Chronic Kidney Disease

OBJECTIVES

Renin-angiotensin system inhibitors (RASi) are recommended for slowing chronic kidney disease (CKD) progression to kidney failure. Their effectiveness and tolerance as patients age remain uncertain because older patients have often been excluded from clinical trials.

DESIGN

CKD-REIN cohort study.

SETTING AND PARTICIPANTS

We studied 2762 patients with CKD stages 3 and 4 and a clinical indication for RASi enrolled between 2013 and 2016 in 40 nephrology clinics nationally representative in France.

METHODS

The primary outcome was the occurrence of kidney failure or death. The secondary outcomes were the occurrence of cardiovascular events and hospitalizations with acute kidney injury (AKI) or hyperkalemia. A propensity score analysis was performed. We used Cox models to estimate hazard ratios (HRs) for each outcome associated with RASi prescription and tested interactions with age.

RESULTS

Patients' mean age was 67 years, including 841 (30%) aged 75 years and older; 2178 (79%) were prescribed RASi's. During a median follow-up of 4.6 years, 33% of patients reached kidney failure or died. RASi prescription was associated with a lower risk of kidney failure or death (HR 0.79, 95% CI 0.66, 0.95), an association not modified by age (P for interaction = .72). It was not significantly associated with cardiovascular events. During the first 3 years of follow-up, 14% of patients were hospitalized with AKI or hyperkalemia, but risk was not higher among those prescribed RASi's (HR 0.75, 95% CI 0.55-1.02) and age did not modify its effect (P for interaction = .28).

CONCLUSIONS AND IMPLICATIONS

This study shows that aging does not appear to modify either RASi's beneficial effects on major CKD outcomes or their potential adverse effects.

New Insights into Acute-on-Chronic Kidney Disease in Nephrology Patients: The CKD-REIN Study

BACKGROUND

Acute-on-chronic kidney disease (ACKD) is poorly understood and often overlooked. We studied its incidence, circumstances, determinants, and outcomes in patients with CKD.

METHODS

We used the Kidney Disease Improving Global Outcomes criteria to identify all-stage acute kidney injury (AKI) events in 3033 nephrology outpatients with CKD stage 3-5 participating in the CKD-REIN cohort study (2013-2020), and cause-specific Cox models to estimate hazard ratios (HR, 95% confidence intervals [CI]) of AKI-associated risk factors.

RESULTS

At baseline, 22% of the patients (mean age 67 years, 65% men, mean eGFR 32 ml/min/1.73m2) had a history of AKI. Over a 3-year follow-up, 443 had at least one AKI event: 27% were stage 2 or 3, and 11% required dialysis; 74% involved hospitalization including 47% acquired as hospital inpatients; a third were not reported in hospital discharge reports. Incidence rates were 10.1 and 4.8 per 100 person-years in patients with and without an AKI history, respectively. In 2375 patients without this history, male sex, diabetes, cardiovascular disease, cirrhosis, several drugs, low eGFR, and serum albumin levels were significantly associated with a higher risk of AKI, as were low birth weight (<2500 g) (adjusted HR, 1.98; 95%CI, 1.35 to 2.91) and hemoglobin level (HR 1.21; 1.12 to 1.32 per 1 g/dl decrease). Within one year, only 63% of the patients had recovered their previous kidney function, 13.7% had started kidney replacement therapy, and 12.7% had died.

CONCLUSIONS

The study highlights the high rate of hospital-acquired AKI events in patients with CKD, and their underreporting at hospital discharge. It also reveals low birth weight and anemia as possible new risk factors in CKD patients.

Knowledge of 5-aminosalicylic acid nephrotoxicity and adherence to kidney function monitoring of patients with inflammatory bowel disease

BACKGROUND AND AIM

5-Aminosalicylic acid (5-ASA) nephrotoxicity is a rare and idiosyncratic condition in patients with inflammatory bowel disease (IBD), which may lead to end-stage kidney failure. Kidney function monitoring is recommended in clinical practice to prevent this complication. However, no data is available regarding the knowledge and adherence of patients with IBD to this monitoring.

METHODS

As a part of routine practice, patients with IBD under treatment or previously treated with 5-ASA were systematically interviewed about knowledge of 5-ASA nephrotoxicity and adherence to kidney function monitoring. We reported here the experience among the first 103 consecutive patients seen in a French referral center.

RESULTS

A total of 103 patients (93.2% ulcerative colitis, 5.8% Crohn's disease, and 1% unclassified colitis) were analyzed. Among them, 70% were informed about the need for kidney function monitoring, and in most cases, information was provided by their gastroenterologist (94.4%). The adherence rate to monitoring was very high (84.7%). Monitoring consisted of serum creatinine and estimated glomerular filtration rate in most cases (97.2%), while 24-h proteinuria was less frequently used (69.4%). These tests were performed twice or ≥3 times per year by 44.4 and 41.7% of patients, respectively. One case of isolated elevation of proteinuria related to 5-ASA treatment was observed.

CONCLUSION

We reported for the first time that patients with IBD are well informed and adherent to kidney function monitoring of treatment with 5-ASA. The monitoring performed by their treating physician was generally in accordance with current recommendations.

Temporal trends in living kidney donation in France between 2007 and 2017

BACKGROUND

Long-term studies have demonstrated a slight increased risk for end-stage renal disease (ESRD) for living kidney donors (LKD). In France, living kidney donation doubled within the past 10 years. We investigated the change in characteristics of LKD between 2007 and 2017 and the adequacy of follow-up.

METHODS

Data were obtained from the national registry for LKD. We compared characteristics of LKD between two study periods: 2007-11 and 2012-17, and stratified donors by age and relation to recipient. We aggregated four characteristics associated with higher ESRD risk [young age, first-degree relation to recipient, obesity, low glomerular filtration rate (GFR) for age] in a single risk indicator ranging from 0 to 4.

RESULTS

We included 3483 donors. The proportion of unrelated donors >56 years of age increased significantly. The proportion of related donors <56 years of age decreased significantly. The body mass index and proportion of obese donors did not change significantly. The proportion of donors with low estimated GFR for age decreased significantly from 5% to 2.2% (P < 0.001). The proportion of donors with adequate follow-up after donation increased from 19.6% to 42.5% (P < 0.001). No donor had a risk indicator equal to 4, and the proportion of donors with a risk indicator equal to 0 increased significantly from 19.2% to 24.9% (P < 0.001).

CONCLUSIONS

An increase in living kidney donation in France does not seem to be associated with the selection of donors at higher risk of ESRD and the proportion of donors with adequate annual follow-up significantly increased.

Consequences of oral antithrombotic use in patients with chronic kidney disease

We assessed the risks of bleeding, acute kidney injury (AKI), and kidney failure associated with the prescription of antithrombotic agents (oral anticoagulants and/or antiplatelet agents) in patients with moderate‐to‐advanced chronic kidney disease (CKD). CKD‐REIN is a prospective cohort of 3022 nephrology outpatients with CKD stages 2–5 at baseline. We used cause‐specific Cox proportional hazard models to estimate hazard ratios (HRs) for bleeding (identified through hospitalizations), AKI, and kidney failure. Prescriptions of oral antithrombotics were treated as time‐dependent variables. At baseline, 339 (11%) patients (65% men; 69 [60–76] years) were prescribed oral anticoagulants only, 1095 (36%) antiplatelets only, and 101 (3%) both type of oral antithrombotics. Over a median (interquartile range [IQR]) follow‐up period of 3.0 (IQR, 2.8–3.1) years, 152 patients experienced a bleeding event, 414 patients experienced an episode of AKI, and 270 experienced kidney failure. The adjusted HRs (95% confidence interval [95% CI]) for bleeding associated with prescriptions of antiplatelets only, oral anticoagulants only, and antiplatelet + oral anticoagulant were, respectively, 0.74 (95% CI, 0.46–1.19), 2.38 (95% CI, 1.45–3.89), and 3.96 (95% CI, 2.20–7.12). An increased risk of AKI risk was associated with the prescription of oral anticoagulants (adjusted HR, 1.90, 95% CI, 1.47–2.45) but not the prescription of antiplatelets (HR, 1.24, 95% CI, 0.98–1.56). Kidney failure was not associated with the prescription of oral antithrombotics of any type. This study confirms the high risk of AKI associated with oral anticoagulants prescription in patients with CKD and also highlights the potential aggravating effect of combining vitamin K antagonist (VKA) and antiplatelets on the risk of bleeding.

Kidney function monitoring to prevent 5-aminosalicylic acid nephrotoxicity: What the gastroenterologist should know

BACKGROUND

The kidney function monitoring is recommended in routine practice to detect 5-aminosalicylic acid (5-ASA) related nephrotoxicity, although is not standardized. The optimal monitoring is unknown, especially the best timing and which tests to perform. We summarized why, how, and when to perform the monitoring for patients treated with 5-ASA and provided an overview of the current guidelines on this topic.

METHOD

Relevant studies on this topic were searched in PubMed, Embase, and Web of Science databases from July to August 2020.

RESULTS

Serum creatinine, the estimated glomerular filtration rate, and 24-h proteinuria are the 3 main tests used for the monitoring in daily practice. Regarding the timing, several monitoring strategies have been proposed and guidelines are available too, but they provide conflicting information. To date, there is no medical evidence-based that one strategy is better than another. Comorbidities, chronic renal disease, use of nephrotoxic drugs or concomitant steroid therapy also impact the nephrotoxicity risk. Based on the literature review we proposed a kidney function monitoring strategy to guide physicians in clinical practice.

CONCLUSION

A baseline assessment should be performed in all patients treated with 5-ASA. The monitoring should be carried out according to the other nephrotoxic factors. A tight monitoring may reduce morbidity and mortality of drug nephrotoxicity.

FC 126IMPACT OF POLYCLONAL ANTI-T-LYMPHOCYTE IMMUNOGLOBULINS ON THE RECURRENCE OF IGA NEPHROPATHY AFTER KIDNEY TRANSPLANTATION: THE PIRAT STUDY

Background and Aims

IgA Nephropathy (IgAN) often recurs on kidney transplants, accounting for a significant specific kidney failure occurrence after ten years of transplantation vintage. Polyclonal anti-T-lymphocyte antibodies (PATLA) immunosuppressive induction has been shown to be associated with a lower rate of IgAN recurrence compared to basiliximab and no induction in a retrospective study. The aim of the PIRAT study was to compare an induction by PATLA versus basiliximab by the mean of a randomized controlled trial.

Method

Adults with biopsy-proven primary IgAN as primary cause of end stage of renal disease, first transplantation, panel reactive antibody &lt;50% could be included in the study. Patients were randomized 1:1 prior to transplantation to receive either PATLA (Grafalon, 4mg/kg for 3 days, then two days 3mg/kg) or basiliximab (20mg at transplantation and 4 days after). Both groups received methylprednisolone followed by oral corticoids for at least one year, tacrolimus and mycophenolic acid. Primary outcome was the clinico-histological recurrence defined by both IgA deposition on transplant biopsy and albuminuria&gt;300mg/d during 5 years post-transplantation. Protocol biopsy at 5 years was highly recommended.

Results

A total of 117 patients were finally included in 13 French transplant centers, with 60 patients in the PATLA group and 57 in the basiliximab control group. Both groups were similar (median, PATLA vs. basiliximab, p&gt;0.05 wilcoxon test) in term of sex ratio (4.45 vs 4.57), recipient age (47.9 vs. 47.7 years old), dialysis vintage (26.2 vs. 24.6 months), age at IgAN diagnosis (35.0 vs. 42.2 years old), cold ischemia (780 min vs 682 min), warm ischemia (34 vs. 36.1min), proportion of living donors (33% vs. 25%). The 5-year protocol biopsy was performed on 48% vs. 45% of patients, with overall proportion of patients evaluated by at least one biopsy of 63% vs. 66%.

A trend in favor to the protection by PATLA from the occurrence of a clinico-histological recurrence was found (hazard ratio, univariate Cox model 0,35 [0.11-1.1], p=0.082).

Biopsy proven histological recurrence was significantly lower after PATLA induction (HR 0.34 [0.16-0.76], p=0.0079). PATLA group experienced more infections (40 vs. 28 p=0.06), a lower number of graft losses (3 vs 9, p=0.07), a lower number of biopsy-proven acute rejections (5 vs 10, p=0.17). Similar rates of cytomegalovirus and BK virus infections were found.

Conclusion

PATLA for immunosuppressive induction was found protective from the recurrence of IgA deposition during the first 5 years after transplantation, compared to basiliximab. A similar trend, although not significant, was found about the clinico-histological recurrence which was the predefined primary outcome.

MO484ADVERSE OUTCOMES ASSOCIATED WITH ORAL ANTITHROMBOTIC USE IN PATIENTS WITH MODERATE-TO-ADVANCED CHRONIC KIDNEY DISEASE*

Background and Aims

The use of oral antithrombotics in patients with chronic kidney disease (CKD) is challenging because of altered pharmacodynamics/pharmacokinetics. Patients prescribed oral anticoagulant are at high risk of bleeding, and possibly also acute kidney injury (AKI) and progression to kidney failure. We assessed bleeding, AKI, and kidney failure risks associated with oral anticoagulant and/or antiplatelet agent prescription in patients with moderate-to-advanced CKD.

Method

CKD-REIN is a prospective cohort of 3022 nephrology outpatients with CKD stages 2-5 at inclusion. Drug prescriptions and their duration were collected prospectively. We used cause-specific Cox proportional hazard models to estimate hazard ratios (HR) for bleeding (identified through hospitalizations), AKI (as defined according to KDIGO 2012), and kidney failure. Prescriptions of oral antithrombotics were treated as a time dependent variable and models were adjusted for baseline comorbidities, laboratory data, and other medications.

Results

At baseline, 339 (11%) patients (65% men; median age 69 [interquartile range (IQR), 60-76] years; median eGFR 32 [IQR, 23-41] were prescribed oral anticoagulants only, 1095 (36%) antiplatelet only, and 101 (3%) both anticoagulant and antiplatelet.

Over a median follow-up of 3 years (IQR, 2.8-3.1), 152 patients experienced a bleeding event requiring hospital visit/stay (crude incidence rate (IR): 1.9% person-years [95%CI,1.6-2.2]), 414 patients experienced AKI (crude IR: 5.4 % person-years [4.9-5.9]), and 270 experienced kidney failure (crude IR: 3.4 % person-years [3.0-3.8]).

A significant interaction was found between oral antithrombotics and eGFR (interaction p=0.03). The adjusted HRs [95%CI] for bleeding associated with prescriptions of antiplatelets only, oral anticoagulants only, and antiplatelet + oral anticoagulant were respectively 0.58 [0.30; 1.11], 2.62 [1.39; 4.93], and 5.76 [2.85; 11.66] in patients with a baseline eGFR &lt; 30 mL/min/1.73m2. In patients with baseline eGFR ≥ 30 mL/min/1.73m2, the adjusted HRs [95%CI] for bleeding associated with prescriptions of antiplatelets only, oral anticoagulants .......only, and antiplatelet + oral anticoagulant were respectively 0.98 [0.48; 1.98], 1.91 [0.87; 4.20], and 1.54 [0.46; 5.12] (Figure 1A).

An increased risk of AKI risk was associated with the prescription of oral anticoagulants (adjusted HR [95%CI]: 1.91[1.48; 2.46]) but not the prescription of antiplatelets (1.24[0.98; 1.56], Figure 1B). No significant interactions were found between oral anticoagulants and eGFR or antiplatelet agents.

Kidney failure was not associated with the prescription of oral antithrombotics of any type (Figure 1C). No significant interactions were found with eGFR and antiplatelet agents.

Conclusion

This study confirms the risk of AKI in CKD patients prescribed oral anticoagulants. It also highlights the potential aggravating effect of combining anticoagulants and antiplatelet on the risk of bleeding in this population.

Living kidney donor evaluation for all candidates with normal estimated GFR for age

Multiple days assessments are frequent for the evaluation of candidates to living kidney donation, combined with an early GFR estimation (eGFR). Living kidney donation is questionable when eGFR is <90 ml/min/1.73 m² (KDIGO guidelines) or 80 ml/min/1.73 m² (most US centres). However, age-related GFR decline results in a lower eGFR for older candidates. That may limit the number of older kidney donors. Yet, continuing the screening with a GFR measure increases the number of eligible donors. We hypothesized that in-depth screening should be proposed to all candidates with a normal eGFR for age. We compared the evolution of eGFR after donation between three groups of predonation eGFR: normal for age (S_age ) higher than 90 or 80 ml/min/1.73 m² (S₉₀ and S_80, respectively); across three age groups (<45, 45-55, >55 years) in a population of 1825 French living kidney donors with a median follow-up of 5.9 years. In donors younger than 45, postdonation eGFR, absolute- and relative-eGFR variation were not different between the three groups. For older donors, postdonation eGFR was higher in S₉₀ than in S₈₀ or S_age but other comparators were identical. Postdonation eGFR slope was comparable between all groups. Our results are in favour of in-depth screening for all candidates to donation with a normal eGFR for age.