Supplementary Material for: Characteristics and prognostic factors of SARS-CoV-2 Omicron variant infection in hemodialysis patients: a single-center study in China

Introduction: This study aimed to evaluate the characteristics and prognostic factors for coronavirus disease 2019 (COVID-19) patients on maintenance hemodialysis (HD). Methods: All admitted HD patients who were infected with severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) from December 1, 2022 to January 31, 2023 were included. Patients with pneumonia were further classified into the mild, moderate, severe and critical illness. Clinical symptoms, laboratory results, radiologic findings, treatment and clinical outcomes were collected. Independent risk factors for progression to critical disease, and in-hospital mortality were determined by the multivariate regression analysis. The receiver operating characteristic (ROC) analysis with the area under the curve (AUC) was used to evaluate the predictive performance of developing critical status and in-hospital mortality. Results: A total of 182 COVID-19 patients with HD were included, with an average age of the 61.55 years. Out of the total, 84 (46.1%) patients did not have pneumonia and 98 (53.8%) patients had pneumonia. Among patients with pneumonia, 48 (49.0%) had moderate illness, 26 (26.5%) severe illness, and 24 (24.5%) critical illness, respectively. Elder age [HR (95% CI): 1.07 (1.01-1.13), P<0.01], increased levels of lactate dehydrogenase (LDH) [1.01 (1.003-1.01), P<0.01] and C-reactive protein (CRP) [1.01 (1.00-1.01), P=0.04] were risk factors for developing critical illness. Elder age [1.11 (1.03-1.19), P=0.01], increased procalcitonin (PCT) [1.07 (1.02-1.12), P=0.01], and LDH level [1.004 (1-1.01), P=0.03] were factors associated with increased risk of in-hospital mortality. Conclusions: Age, CRP, PCT and LDH can be used to predict negative clinical outcomes for HD patients with COVID-19 pneumonia.