Strategies to prevent SARS-CoV-2 transmission in hemodialysis centres across Europe-lessons for the future.

Background: Early reports on the pandemic nature of coronavirus disease 2019 (COVID-19) directed the nephrology community to develop infection prevention and control (IPC) guidance. We aimed to make an inventory of strategies that dialysis centres followed to prevent infection with COVID-19 in the first pandemic wave. Methods: We analyzed IPC measures taken by hemodialysis centres treating patients presenting with COVID-19 between 1 March 2020 and 31 July 2020 and that completed the European Renal Association COVID-19 Database centre questionnaire. Additionally, we made an inventory of guidelines published in European countries to prevent spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in dialysis centres. Results: Data from 73 dialysis units located in and bordering Europe were analyzed. All participating centres implemented IPC measures to mitigate the impact of SARS-CoV-2 during the first pandemic wave. Measures mentioned most often included triage with questions before entering the dialysis ward, measuring body temperature, hand disinfection, masking for all patients and staff, and personal protective equipment for staff members. These measures were also recommended in most of the 14 guidelines that were identified in the inventory of national guidelines and were also scored as being among the most important measures by the authors of this paper. Heterogeneity existed between centres and national guidelines regarding the minimal distance between dialysis chairs and recommendations regarding isolation and cohorting. Conclusions: Although variation existed, measures to prevent transmission of SARS-CoV-2 were relatively similar across centres and national guidelines. Further research is needed to assess causal relationships between measures taken and spread of SARS-CoV-2.

Preparing European Nephrology for the next pandemic: lessons from the ERACODA collaboration.

Owing to the vulnerability of patients with chronic kidney disease to infectious diseases, the coronavirus disease 2019 (COVID-19) pandemic has been particularly devastating for the nephrology community. Unfortunately, the possibility of future COVID-19 waves or outbreaks of other infectious diseases with pandemic potential cannot be ruled out. The nephrology community made tremendous efforts to contain the consequences of the COVID-19 pandemic. Despite this, the COVID-19 pandemic has highlighted several shortcomings in our response to the pandemic and has taught us important lessons that can be utilized to improve our preparedness for any future health crises of similar nature. In this article we draw lessons from the European Renal Association COVID-19 Database (ERACODA) project, a pan-European collaboration initiated in March 2020 to understand the prognosis of COVID-19 in patients on kidney function replacement therapy. We discuss challenges faced in generating timely and robust evidence for informed management of patients with kidney disease and give recommendations for our preparedness for the next pandemic in Europe. Limited collaboration, the absence of common data architecture, and the sub-optimal quality of available data posed challenges in our response to COVID-19. Aligning different research initiatives, strengthening electronic health records, and involving experts in study design and data analysis will be important in our response to the next pandemic. The European Renal Association may take a leading role in aligning research initiatives via its engagement with other scientific societies, national registries, administrators, and researchers.

Outcomes of COVID-19 in peritoneal dialysis patients: A report by the European Renal Association COVID-19 Database.

BACKGROUND: The clinical course of COVID-19 in peritoneal dialysis (PD) patients has so far only been analysed in relatively small, often single-centre case series. Therefore, we studied patient- and disease-related characteristics and outcomes of COVID-19 in a larger European cohort of PD patients. METHODS: We used data from the European Renal Association COVID-19 Database (ERACODA) on PD and haemodialysis (HD) patients with COVID-19 (presentation between February 2020 and April 2021). Hazard ratios (HR) for mortality at 3 months were calculated using Cox proportional-hazards regression. In addition, we examined functional and mental health status among survivors at this time point as determined by their treating physician. RESULTS: Of 216 PD patients with COVID-19, 80 (37%) were not hospitalised and 136 (63%) were hospitalised, of whom 19 (8.8%) were admitted to an intensive care unit. Mortality at 3 months for these subgroups was 18%, 40%, and 37%, respectively (p = 0.0031). Compared with HD patients, PD patients had higher mortality (crude HR: 1.49; 95% CI: 1.33-1.66), even when adjusted for patient characteristics and disease severity (adjusted HR: 1.56; 95% CI: 1.39-1.75). Follow-up data on 67 of 146 patients who survived COVID-19 showed functional recovery to pre-COVID-19 levels in 52 (78%) and mental recovery in 58 patients (87%) at 3 months after the COVID-19 diagnosis. CONCLUSION: The mortality rate in the first 3 months after presentation with COVID-19 is high, especially among PD patients who were hospitalised. PD patients with COVID-19 had a higher mortality risk than HD patients. The majority of surviving patients recovered both functionally and mentally from COVID-19 within 3 months.

Sex differences in COVID-19 mortality risk in patients on kidney function replacement therapy.

In the general population with COVID-19, the male sex is an established risk factor for mortality, in part due to a more robust immune response to COVID-19 in women. Because patients on kidney function replacement therapy (KFRT) have an impaired immune response, especially kidney transplant recipients due to their use of immunosuppressants, we examined whether the male sex is still a risk factor for mortality among patients on KFRT with COVID-19. From the European Renal Association COVID-19 Database (ERACODA), we examined patients on KFRT with COVID-19 who presented between February 1st, 2020, and April 30th, 2021. 1204 kidney transplant recipients (male 62.0%, mean age 56.4 years) and 3206 dialysis patients (male 61.8%, mean age 67.7 years) were examined. Three-month mortality in kidney transplant recipients was 16.9% in males and 18.6% in females (p = 0.31) and in dialysis patients 27.1% in males and 21.9% in females (p = 0.001). The adjusted HR for the risk of 3-month mortality in males (vs females) was 0.89 (95% CI 65, 1.23, p = 0.49) in kidney transplant recipients and 1.33 (95% CI 1.13, 1.56, p = 0.001) in dialysis patients (pinteraction = 0.02). In a fully adjusted model, the aHR for the risk of 3-month mortality in kidney transplant recipients (vs. dialysis patients) was 1.39 (95% CI 1.02, 1.89, p = 0.04) in males and 2.04 (95% CI 1.40, 2.97, p < 0.001) in females (pinteraction = 0.02). In patients on KFRT with COVID-19, the male sex is not a risk factor for mortality among kidney transplant recipients but remains a risk factor among dialysis patients. The use of immunosuppressants in kidney transplant recipients, among other factors, may have narrowed the difference in the immune response to COVID-19 between men and women, and therefore reduced the sex difference in COVID-19 mortality risk.

Sex Difference in COVID-19 Mortality Risk among Patients on Kidney Function Replacement Therapy

BACKGROUND AND AIMS In the general population with COVID-19, male sex is an established risk factor for mortality. A more robust immune response to COVID-19 in women has been suggested to be one of the factors explaining this sex difference in mortality. Patients on kidney function replacement therapy (KFRT) have an impaired immune response, especially kidney transplant recipients due to their use of immunosuppressants. In this study, we therefore examined whether male sex is still a risk factor for mortality among patients on KFRT with COVID-19. METHOD Data were used from the European Renal Association COVID-19 Database (ERACODA) of kidney transplant recipients and dialysis patients who presented with COVID-19 between 1 February 2020 and 30 April 2021. The primary study outcome was 3-month mortality. As secondary outcomes, in-hospital mortality and 28-day mortality were examined. Associations were investigated using multivariable Cox proportional-hazards regression analysis. Assuming immunosuppressant use is among the main factors contributing to excess mortality in kidney transplant recipients compared with dialysis patients, we also investigated the association of type of KFRT with mortality by sex. RESULTS ERACODA included 1204 kidney transplant recipients (male: 62.0%, mean age: 56.4 years) and 3206 dialysis patients (male: 61.8%, mean age: 67.7 years). Three-month mortality in kidney transplant recipients was 16.9% in males and 18.6% in females (P = 0.31) and in dialysis patients 27.1% in males and 21.9% in females (P = 0.001). In a model adjusted for age, frailty, smoking and comorbidities, the aHR for the risk of 3-month mortality in males (versus females) was 0.87 (95% CI: 63, 1.21, P = 0.41) in kidney transplant recipients and 1.32 (95% CI: 1.13, 1.55, P = 0.001) in dialysis patients (P for interaction = 0.03). In a fully adjusted model, the aHR for the risk of 3-month mortality in kidney transplant recipients (versus dialysis patients) was 1.26 (95% CI: 1.02, 1.56, P = 0.03) in males and 1.73 (95% CI: 1.31, 2.27, P < 0.001) in females (p for interaction = 0.03). Essentially similar results were obtained for in-hospital mortality and 28-day mortality. CONCLUSION In patients on kidney function replacement therapy with COVID-19, male sex is not a risk factor for mortality among kidney transplant receipts but remains a risk factor among dialysis patients. The use of immunosuppressants in kidney transplant recipients, among other factors, may have narrowed the difference in the immune response to COVID-19 between men and women, and therefore reduced the sex difference in COVID-19 mortality risk.

The Clinical Frailty Scale as a triage tool for ICU admission of dialysis patients with COVID-19: an ERACODA analysis.

BACKGROUND: Several guidelines recommend using the Clinical Frailty Scale (CFS) for triage of critically ill coronavirus disease 2019 (COVID-19) patients. This study evaluates the impact of CFS on intensive care unit (ICU) admission rate and hospital and ICU mortality rates in hospitalized dialysis patients with COVID-19. METHODS: We analysed data of dialysis patients diagnosed with COVID-19 from the European Renal Association COVID-19 Database. The primary outcome was ICU admission rate and secondary outcomes were hospital and ICU mortality until 3 months after COVID-19 diagnosis. Cox regression analyses were performed to assess associations between CFS and outcomes. RESULTS: A total of 1501 dialysis patients were hospitalized due to COVID-19, of whom 219 (15%) were admitted to an ICU. The ICU admission rate was lowest (5%) in patients >75 years of age with a CFS of 7-9 and highest (27%) in patients 65-75 years of age with a CFS of 5. A CFS of 7-9 was associated with a lower ICU admission rate than a CFS of 1-3 [relative risk 0.49 (95% confidence interval 0.27-0.87)]. Overall, mortality at 3 months was 34% in hospitalized patients, 65% in ICU-admitted patients and highest in patients >75 years of age with a CFS of 7-9 (69%). Only 9% of patients with a CFS ≥6 survived after ICU admission. After adjustment for age and sex, each CFS category ≥4 was associated with higher hospital and ICU mortality compared with a CFS of 1-3. CONCLUSIONS: Frail dialysis patients with COVID-19 were less frequently admitted to the ICU. Large differences in mortality rates between fit and frail patients suggest that the CFS may be a useful complementary triage tool for ICU admission in dialysis patients with COVID-19.

The Clinical frailty Scale is Useful for ICU Triage in Dialysis Patients With COVID-19–An Eracoda Analysis

BACKGROUND AND AIMS during the COVID-19 pandemic, several guidelines have recommended the use of the Clinical Frailty Scale (CFS) for triage of critically ill patients with COVID-19 in case of shortage in ICU resources. However, no data on using CFS assessment for ICU triage for dialysis patients is yet available. This study evaluates whether CFS is associated with mortality rates in a cohort of hospitalized dialysis patients with COVID-19. METHOD the analyses are based on data of the European Renal Association COVID-19 Database (ERACODA). Dialysis patients who presented with COVID-19 between 1 February 2020 and 30 April 2021 and with complete information on CFS and vital status at 3 months were included. Study outcomes were hospital and ICU admission rates and hospital and ICU mortality at 3 months after hospital admission. Cox regression analyses were performed to assess the association of CFS category (≤5 versus ≥ 6) and study outcomes in line with Dutch ICU triage guidelines for COVID-19. Furthermore, additional subgroup analyses were performed to assess the association between CFS and 3-month mortality by age category (<65, 65–75 and >75 years). RESULTS among a total of 2206 dialysis patients (mean age = 67.2 (14.1) years, male sex = 61%), 1694 (77%) had CFS ≤ 5 and 514 (23%) had CFS ≥ 6. Hospitalization rate was comparable in patients with CFS ≤ 5 and in patients with CFS ≥ 6 (67 and 71%, respectively), whereas the rate of ICU admission was higher in patients with CFS ≤ 5 than in patients with CFS ≥ 6 (16 versus 9%, p = 0.001). Among 1501 hospitalized patients, 3-month mortality was 26% of patients with CFS ≤ 5 and 59% in patients with CFS ≥ 6 (P < 0.001). Multivariate analysis with adjustment for patient demographics, smoking status and BMI revealed that CFS ≥ 6 was associated with hospital mortality [aHR 2.27 (1.88–2.74) versus CFS ≤ 5;P < 0.001) with a significant interaction for age (P = 0.029). aHR was 4.00 (2.56–6.37;CFS ≥ 6 versus CFS ≤ 5;P < 0.001) in patients < 65 years, aHR was 1.87 (1.33–2.64;CFS ≥ 6 versus CFS ≤ 5;P < 0.001) in patients 65–75 years and aHR was 2.12 (1.64–2.75;CFS ≥ 6 versus CFS ≤ 5;P < 0.001) in patients >75 years. Among 219 ICU admitted patients, 3-month mortality was 60% of the patients with CFS ≤ 5 and 91% in the patients with CFS ≥ 6, respectively. Multivariate analysis with adjustment for patient demographics, smoking status and BMI revealed that CFS ≥ 6 was associated with ICU mortality [aHR 1.80 (1.17–2.77);CFS ≥ 6 versus CFS ≤ 5;P = 0.002]. CONCLUSION more frail dialysis patients with CFS ≥ 6 who are hospitalized for COVID-19 were less often admitted to the ICU, but in case they were admitted to the ICU they have a very high mortality of 91% in this cohort study. In fit to mildly frail dialysis, patients who were admitted to the ICU, mortality rates are lower. The association between frailty and hospital mortality is interacted by age with the strongest association in patients younger than 65 years. These findings suggest that CFS may be a useful complementary triage tool for ICU admission of dialysis patients during the ongoing COVID-19 pandemic.

Association of obesity with 3-month mortality in kidney failure patients with COVID-19.

Background: In the general population with coronavirus disease 2019 (COVID-19), obesity is associated with an increased risk of mortality. Given the typically observed obesity paradox among patients on kidney function replacement therapy (KFRT), especially dialysis patients, we examined the association of obesity with mortality among dialysis patients or living with a kidney transplant with COVID-19. Methods: Data from the European Renal Association COVID-19 Database (ERACODA) were used. KFRT patients diagnosed with COVID-19 between 1 February 2020 and 31 January 2021 were included. The association of Quetelet's body mass index (BMI) (kg/m2), divided into: <18.5 (lean), 18.5-24.9 (normal weight), 25-29.9 (overweight), 30-34.9 (obese I) and ≥35 (obese II/III), with 3-month mortality was investigated using Cox proportional-hazards regression analyses. Results: In 3160 patients on KFRT (mean age: 65 years, male: 61%), 99 patients were lean, 1151 normal weight (reference), 1160 overweight, 525 obese I and 225 obese II/III. During follow-up of 3 months, 28, 20, 21, 23 and 27% of patients died in these categories, respectively. In the fully adjusted model, the hazard ratios (HRs) for 3-month mortality were 1.65 [95% confidence interval (CI): 1.10, 2.47], 1 (ref.), 1.07 (95% CI: 0.89, 1.28), 1.17 (95% CI: 0.93, 1.46) and 1.71 (95% CI: 1.27, 2.30), respectively. Results were similar among dialysis patients (N = 2343) and among those living with a kidney transplant (N = 817) (Pinteraction = 0.99), but differed by sex (Pinteraction = 0.019). In males, the HRs for the association of aforementioned BMI categories with 3-month mortality were 2.07 (95% CI: 1.22, 3.52), 1 (ref.), 0.97 (95% CI: 0.78. 1.21), 0.99 (95% CI: 0.74, 1.33) and 1.22 (95% CI: 0.78, 1.91), respectively, and in females corresponding HRs were 1.34 (95% CI: 0.70, 2.57), 1 (ref.), 1.31 (95% CI: 0.94, 1.85), 1.54 (95% CI: 1.05, 2.26) and 2.49 (95% CI: 1.62, 3.84), respectively. Conclusion: In KFRT patients with COVID-19, on dialysis or a kidney transplant, obesity is associated with an increased risk of mortality at 3 months. This is in contrast to the obesity paradox generally observed in dialysis patients. Additional studies are required to corroborate the sex difference in the association of obesity with mortality.

Clinical, Functional, and Mental Health Outcomes in Kidney Transplant Recipients 3 Months After a Diagnosis of COVID-19.

BACKGROUND: Kidney transplant patients are at high risk for coronavirus disease 2019 (COVID-19)-related mortality. However, limited data are available on longer-term clinical, functional, and mental health outcomes in patients who survive COVID-19. METHODS: We analyzed data from adult kidney transplant patients in the European Renal Association COVID-19 Database who presented with COVID-19 between February 1, 2020, and January 31, 2021. RESULTS: We included 912 patients with a mean age of 56.7 (±13.7) y. 26.4% were not hospitalized, 57.5% were hospitalized without need for intensive care unit (ICU) admission, and 16.1% were hospitalized and admitted to the ICU. At 3 mo follow-up survival was 82.3% overall, and 98.8%, 84.2%, and 49.0%, respectively, in each group. At 3 mo follow-up biopsy-proven acute rejection, need for renal replacement therapy, and graft failure occurred in the overall group in 0.8%, 2.6%, and 1.8% respectively, and in 2.1%, 10.6%, and 10.6% of ICU-admitted patients, respectively. Of the surviving patients, 83.3% and 94.4% reached their pre-COVID-19 physician-reported functional and mental health status, respectively, within 3 mo. Of patients who had not yet reached their prior functional and mental health status, their treating physicians expected that 79.6% and 80.0%, respectively, still would do so within the coming year. ICU admission was independently associated with a low likelihood to reach prior functional and mental health status. CONCLUSIONS: In kidney transplant recipients alive at 3-mo follow-up, clinical, physician-reported functional, and mental health recovery was good for both nonhospitalized and hospitalized patients. Recovery was, however, less favorable for patients who had been admitted to the ICU.

Association of obesity with 3-month mortality in kidney failure patients with COVID-19

Background In the general population with COVID-19, obesity is associated with an increased risk of mortality. Given the typically observed obesity paradox among patients on kidney function replacement therapy (KFRT), especially dialysis patients, we examined the association of obesity with mortality among dialysis patients or living with a kidney transplant with COVID-19. Methods Data from the European Renal Association COVID-19 Database (ERACODA) were used. KFRT-patients diagnosed with COVID-19 between February 1st, 2020, and January 31st, 2021 were included. The association of Quetelet's body mass index (BMI) (kg/m2), divided into: <18.5 (lean), 18.5-24.9 (normal weight), 25-29.9 (overweight), 30-34.9 (obese I) and ≥35 (obese II/III), with 3-month mortality was investigated using Cox proportional-hazards regression analyses. Results In 3,160 patients on KFRT (mean age:65 years, male:61%), 99 patients were lean, 1,151 normal weight (reference), 1,160 overweight, 525 obese I, and 225 obese II/III. During follow-up of 3 months, 28%, 20%, 21%, 23%, and 27% of patients died in these categories, respectively. In the fully adjusted model, the HRs for 3-month mortality were 1.65 (95%CI:1.10,2.47), 1 (ref.), 1.07 (95%CI:0.89,1.28), 1.17 (95%CI:0.93,1.46) and 1.71 (95%CI:1.27,2.30), respectively. Results were similar among dialysis patients (N = 2,343) and among those living with a kidney transplant (N = 817) (pinteraction = 0.99), but differed by sex (pinteraction = 0.019). In males, the HRs for the association of aforementioned BMI categories with 3-month mortality were 2.07 (95% CI:1.22, 3.52), 1 (Ref.), 0.97 (95% CI: 0.78. 1.21), 0.99 (95% CI: 0.74, 1.33) and 1.22 (95%CI:0.78, 1.91) respectively, and in females corresponding HRs were 1.34 (95% CI: 0.70, 2.57), 1 (Ref.), 1.31 (95% CI: 0.94, 1.85), 1.54 (95% CI: 1.05, 2.26) and 2.49 (95%CI:1.62, 3.84) respectively.”. Conclusion In KFRT-patients with COVID-19, on dialysis or a kidney transplant, obesity is associated with an increased risk of mortality at 3 months. This is in contrast to the obesity paradox generally observed in dialysis patients. Additional studies are required to corroborate the sex difference in the association of obesity with mortality.

Recovery of dialysis patients with COVID-19: health outcomes 3 months after diagnosis in ERACODA.

BACKGROUND: Coronavirus disease 2019 (COVID-19)-related short-term mortality is high in dialysis patients, but longer-term outcomes are largely unknown. We therefore assessed patient recovery in a large cohort of dialysis patients 3 months after their COVID-19 diagnosis. METHODS: We analyzed data on dialysis patients diagnosed with COVID-19 from 1 February 2020 to 31 March 2021 from the European Renal Association COVID-19 Database (ERACODA). The outcomes studied were patient survival, residence and functional and mental health status (estimated by their treating physician) 3 months after COVID-19 diagnosis. Complete follow-up data were available for 854 surviving patients. Patient characteristics associated with recovery were analyzed using logistic regression. RESULTS: In 2449 hemodialysis patients (mean ± SD age 67.5 ± 14.4 years, 62% male), survival probabilities at 3 months after COVID-19 diagnosis were 90% for nonhospitalized patients (n = 1087), 73% for patients admitted to the hospital but not to an intensive care unit (ICU) (n = 1165) and 40% for those admitted to an ICU (n = 197). Patient survival hardly decreased between 28 days and 3 months after COVID-19 diagnosis. At 3 months, 87% functioned at their pre-existent functional and 94% at their pre-existent mental level. Only few of the surviving patients were still admitted to the hospital (0.8-6.3%) or a nursing home (∼5%). A higher age and frailty score at presentation and ICU admission were associated with worse functional outcome. CONCLUSIONS: Mortality between 28 days and 3 months after COVID-19 diagnosis was low and the majority of patients who survived COVID-19 recovered to their pre-existent functional and mental health level at 3 months after diagnosis.

COVID-19-related mortality in kidney transplant and haemodialysis patients: a comparative, prospective registry-based study.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has exposed haemodialysis (HD) patients and kidney transplant (KT) recipients to an unprecedented life-threatening infectious disease, raising concerns about kidney replacement therapy (KRT) strategy during the pandemic. This study investigated the association of the type of KRT with COVID-19 severity, adjusting for differences in individual characteristics. METHODS: Data on KT recipients and HD patients diagnosed with COVID-19 between 1 February 2020 and 1 December 2020 were retrieved from the European Renal Association COVID-19 Database. Cox regression models adjusted for age, sex, frailty and comorbidities were used to estimate hazard ratios (HRs) for 28-day mortality risk in all patients and in the subsets that were tested because of symptoms. RESULTS: A total of 1670 patients (496 functional KT and 1174 HD) were included; 16.9% of KT and 23.9% of HD patients died within 28 days of presentation. The unadjusted 28-day mortality risk was 33% lower in KT recipients compared with HD patients {HR 0.67 [95% confidence interval (CI) 0.52-0.85]}. In a fully adjusted model, the risk was 78% higher in KT recipients [HR 1.78 (95% CI 1.22-2.61)] compared with HD patients. This association was similar in patients tested because of symptoms [fully adjusted model HR 2.00 (95% CI 1.31-3.06)]. This risk was dramatically increased during the first post-transplant year. Results were similar for other endpoints (e.g. hospitalization, intensive care unit admission and mortality >28 days) and across subgroups. CONCLUSIONS: KT recipients had a greater risk of a more severe course of COVID-19 compared with HD patients, therefore they require specific infection mitigation strategies.

Renin-Angiotensin System Blockers and the Risk of COVID-19-Related Mortality in Patients with Kidney Failure.

BACKGROUND AND OBJECTIVES: There is concern about potential deleterious effects of angiotensin-converting enzyme inhibitors (ACEis) and angiotensin II receptor blockers (ARBs) in patients with coronavirus disease 2019 (COVID-19). Patients with kidney failure, who often use ACEis/ARBs, are at higher risk of more severe COVID-19. However, there are no data available on the association of ACEi/ARB use with COVID-19 severity in this population. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: From the European Renal Association COVID-19 database (ERACODA), we retrieved data on kidney transplant recipients and patients on dialysis who were affected by COVID-19, between February 1 and October 1, 2020, and had information on 28-day mortality. We used Cox proportional-hazards regression to calculate hazard ratios for the association between ACEi/ARB use and 28-day mortality risk. Additionally, we studied the association of discontinuation of these agents with 28-day mortality. RESULTS: We evaluated 1511 patients: 459 kidney transplant recipients and 1052 patients on dialysis. At diagnosis of COVID-19, 189 (41%) of the transplant recipients and 288 (27%) of the patients on dialysis were on ACEis/ARBs. A total of 88 (19%) transplant recipients and 244 (23%) patients on dialysis died within 28 days of initial presentation. In both groups of patients, there was no association between ACEi/ARB use and 28-day mortality in both crude and adjusted models (in transplant recipients, adjusted hazard ratio, 1.12; 95% confidence interval [95% CI], 0.69 to 1.83; in patients on dialysis, adjusted hazard ratio, 1.04; 95% CI, 0.73 to 1.47). Among transplant recipients, ACEi/ARB discontinuation was associated with a higher mortality risk after adjustment for demographics and comorbidities, but the association was no longer statistically significant after adjustment for severity of COVID-19 (adjusted hazard ratio, 1.36; 95% CI, 0.40 to 4.58). Among patients on dialysis, ACEi/ARB discontinuation was not associated with mortality in any model. We obtained similar results across subgroups when ACEis and ARBs were studied separately, and when other outcomes for severity of COVID-19 were studied, e.g., hospital admission, admission to the intensive care unit, or need for ventilator support. CONCLUSIONS: Among kidney transplant recipients and patients on dialysis with COVID-19, there was no significant association of ACEi/ARB use or discontinuation with mortality.

Pitfalls when comparing COVID-19-related outcomes across studies-lessons learnt from the ERACODA collaboration.

Reported outcomes, such as incidence rates of mortality and intensive care unit admission, vary widely across epidemiological coronavirus disease 2019 (COVID-19) studies, including in the nephrology field. This variation can in part be explained by differences in patient characteristics, but also methodological aspects must be considered. In this review, we reflect on the methodological factors that contribute to the observed variation in COVID-19-related outcomes and their risk factors that are identified in the various studies. We focus on issues that arose during the design and analysis phase of the European Renal Association COVID-19 Database (ERACODA), and use examples from recently published reports on COVID-19 to illustrate these issues.