COVID-19 and outcomes in Chinese peritoneal dialysis patients

Background: Reports on COVID-19 in peritoneal dialysis (PD) patients are scarce in China. This study aimed to describe the characteristics and outcomes of PD patients with COVID-19 after China abandoned the 'zero-COVID' policy. Methods: This single-centre retrospective study included patients receiving PD who underwent testing for COVID-19 infections between 7 December 2022 and 7 January 2023. Outcomes of interest included factors associated with positive COVID-19 testing result and clinical outcomes including COVID-19-related hospitalisation and severe COVID-19, which were analysed using logistic regression analyses. Results: A total of 349 PD patients (male 53.6%, age 49 +/- 13 years old) were included, and 235 patients (67.3%) were infected. There were no significant differences between COVID-19 and non-COVID-19 patients other than higher proportion of vaccinated patients and slow transporters in the patients who tested positive for COVID-19 (44.7% vs. 28.1%, p = 0.003; 8.7% vs. 1.8%, p = 0.03, respectively). Multivariate analysis showed COVID-19 was associated with vaccination (odds ratio (OR): 1.71, 95% confidence interval (CI): 1.02-2.86) and slow transport type (compared with average transport type, OR: 4.52, 95% CI: 1.01-20.21). Among the patients with infection, 38 (16.2%) patients were hospitalised, 18 (7.7%) patients had severe disease and 9 (3.8%) patients died. In multivariate logistic analysis, both age (OR: 1.04, 95% CI: 1.01-1.07; OR: 1.06, 95% CI: 1.02-1.11) and hyponatremia (OR: 5.44, 95% CI: 1.63-18.13; OR: 6.50, 95% CI: 1.77-23.85) were independent risk factors for COVID-19-related hospitalisation and severe disease. Conclusions: Although vaccinated patients were more likely to have tested positive for COVID-19 infection, they appeared to have less severe infection and less need for hospitalisation. Patients who were older with a history of hyponatremia were more likely to experience adverse outcomes from COVID-19.