Identifying prognostic risk factors for poor outcome following COVID-19 disease among in-centre haemodialysis patients: role of inflammation and frailty.

INTRODUCTION: The pandemic of coronavirus disease (COVID-19) has highly affected patients with comorbidities and frailty who cannot self-isolate, such as individuals undergoing haemodialysis. The aim of the study was to identify risk factors for mortality and hospitalisation, which may be useful in future disease spikes. METHODS: We collected data retrospectively from the electronic medical records of all patients receiving a diagnosis of COVID-19 between 11th March and 10th May 2020 undergoing maintenance haemodialysis at four satellite dialysis units from the Royal Free London NHS Foundation Trust, London, UK. Mortality was the primary outcome, and the need for hospitalization was the secondary one. RESULTS: Out of 746 patients undergoing regular haemodialysis, 148 symptomatic patients tested positive for SARS-CoV-2 by RT-PCR and were included in the analysis. The overall mortality rate was 24.3%. By univariate analysis, older age, ischaemic heart disease, lower systolic blood pressure, lower body mass index (BMI) and higher frailty scores were associated with higher rates of mortality (all p value < 0.05). The laboratory factors associated with mortality were higher values of WBC, neutrophil counts, neutrophil to lymphocyte ratios (NLR), C-reactive protein (CRP), bilirubin, ferritin, troponin, and lower serum albumin level (all p value < 0.05). In the logistic regression, mortality was associated with older age and higher CRP, while high levels of NLR and CRP were associated with the need for hospitalization. DISCUSSION: Haemodialysis patients are susceptible to COVID-19 and have a high mortality rate. Our study identifies prognostic risk factors associated with poor outcome including age, frailty and markers of inflammation, which may support more informed clinical decision-making.

Risk of COVID-19 Disease, Dialysis Unit Attributes, and Infection Control Strategy among London In-Center Hemodialysis Patients.

BACKGROUND AND OBJECTIVES: Patients receiving in-center hemodialysis treatment face unique challenges during the coronavirus disease 2019 (COVID-19) pandemic, specifically the need to attend for treatment that prevents self-isolation. Dialysis unit attributes and isolation strategies that might reduce dialysis center COVID-19 infection rates have not been previously examined. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We explored the role of variables, including community disease burden, dialysis unit attributes (size and layout), and infection control strategies, on rates of COVID-19 among patients receiving in-center hemodialysis in London, United Kingdom, between March 2, 2020 and May 31, 2020. The two outcomes were defined as (1) a positive test for infection or admission with suspected COVID-19 and (2) admission to the hospital with suspected infection. Associations were examined using a discrete time multilevel time-to-event analysis. RESULTS: Data on 5755 patients dialyzing in 51 units were analyzed; 990 (17%) tested positive and 465 (8%) were admitted with suspected COVID-19 between March 2 and May 31, 2020. Outcomes were associated with age, diabetes, local community COVID-19 rates, and dialysis unit size. A greater number of available side rooms and the introduction of mask policies for asymptomatic patients were inversely associated with outcomes. No association was seen with sex, ethnicity, or deprivation indices, nor with any of the different isolation strategies. CONCLUSIONS: Rates of COVID-19 in the in-center hemodialysis population relate to individual factors, underlying community transmission, unit size, and layout.