Risk factors for mortality and antibody responses in chronic hemodialysis patients with coronavirus disease 2019: a single-center experience in China

Introduction: This single-center retrospective research aimed to depict the outcomes of coronavirus disease 2019 (COVID-19) in a cohort of patients from China. Methods: We traced the outcomes of 216 MHD patients admitted to the Aerospace Center Hospital of China during a COVID-19 wave . Clinical information was assembled and compared between survivors and non-survivors. Serum immunoglobulin M (IgM) and IgG antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were detected in MHD survivors 90–120 days post-infection. Clinical information was analyzed to find outfactors influencing mortality and antibody responses. Results: Among 216 patients, 207 (95.8%) were evaluated as COVID-19, and 25 (12.1%) passed away within 90 days. Fifty-five (26.6%) patients were needed of hospital admission. Non-survivors had lower levels of hemoglobin and serum albumin, higher levels of alkaline phosphatase, higher white blood cell counts and lower percentage of lymphocytes than survivors. Furthermore, the Clinical Frailty Scale (CFS) scores were higher in non-survivors significantly (p<0.05). Multivariate analysis showed that diabetes (HR 3.98, 95% CI 1.25–12.66, p=0.019), level of frailty according to the CFS (HR 2.10, 95% CI 1.36-3.23, p=0.001) and central venous catheter (CVC) use (hazard ratio [HR] 3.48, 95% confidence interval [CI] 1.18-10.29, p=0.024), had significant impacts on mortality. IgG was positive in 59.5%, and IgM was positive in 3.3% of patients (>1 sample/cutoff) between 90–120 days post-infection. Lower blood C-reactive protein (CRP) levels before the onset of SARS-CoV-2 infection were associated with significantly higher IgG antibody levels at 90-120 days after COVID-19 infection. Discussion: This study identified high mortality rates of SARS-CoV-2 infection among hemodialysis patients. Risk factors associated with mortality include diabetes, frailty, and CVC access. Low level of blood CRP before SARS-CoV-2 infection may predict high antibody responses during convalescence.