422-P: Ferritin and COVID-19 among Dialysis Patients with Diabetes

Early in the COVID-19 pandemic, severe hyperferritinemia, independent of inflammation, manifested as a laboratory characteristic prognostic of poor COVID-19 outcomes, including death. To determine the association between ferritin and COVID-19 infection, hospitalization and mortality in dialysis patients w/ diabetes, we followed 114,881 in-center hemodialysis patients w/ diabetes from January 2020 to March 2022. For incident COVID infection, average ferritin levels from one year to two weeks prior to RT-PCR determined COVID-infection (days-365,-14) were used as baseline. Change in ferritin was defined as the difference between the baseline average and two weeks prior average (-14,0) to the PCR positive test date. For non-infected patients, a PCR test date was randomly chosen. Logistic regression assessed the association of ferritin and change in ferritin w/ COVID-19 infection, hospitalization and mortality, adjusting for age, sex, race, vaccination status, vintage, and lab values. During follow-up, the cumulative incidence or COVID-19 was 23%; in the infected, 33% of the population was hospitalized and 11% died. In multivariable adjusted analysis, higher baseline ferritin (p<0.01) and change in ferritin (p<0.001) were linked w/ increased risk of COVID-19 infection. However, in the infected, neither baseline (p=0.13) nor change in ferritin (p=0.07) were linked w/ hospitalization. Positive change in ferritin, but not baseline ferritin (p=0.85), showed a trend towards an increased mortality risk (p=0.06). Other significant clinical risk factors were lower hgb (p<0.001) for COVID-19, higher baseline NLR (p<0.05) and not being vaccinated (p<0.001) for hospitalization, and higher neutrophil to lymphocyte ratio (<0.001) for mortality. Our data suggest baseline and rise in ferritin are associated w/ risk of COVID-19 but show a weaker relationship w/ hospitalization and death. NLR, which is also indicative of inflammation, is a stronger risk factor for hospitalization and mortality in patients w/ diabetes.