RESUMO
Coronavirus disease 2019 (COVID-19) is characterized by a high heterogeneity of clinical presentation and outcomes. This is also true for patients undergoing maintenance hemodialysis (HD), who, due to specific clinical factors and immune status, represent a distinct subgroup of COVID-19 patients. Starting from this observation in this research letter we tested and validated in two cohorts of HD patients with COVID-19 (derivation and validation cohort, respectively) an innovative model which combines linear mixed effect modeling and cluster analysis on longitudinal. This study aimed to describe a methodology allowing patient stratification from simple and widely available data. Our results could be interesting not only to improve COVID-19 management but also to support the application of longitudinal cluster analysis strategy in other clinical settings.
RESUMO
Background Coronavirus disease 2019 (COVID-19) is a rapidly changing disease. So, in this study, we evaluated the evolution of COVID-19 presentation and course in hemodialysis patients (HD). MethodsWe retrospectively compared clinical data and outcomes of HD patients affected by COVID-19 during the first pandemic waves of 2020 (from March to December 2020-Group 1) with patients diagnosed with COVID-19 from September 2021 to February 2022 (Group 2), after the full completion of vaccination. Then, we distinguished among them patients responsive (antibody levels > 13 binding antibody units/ml) and unresponsive to the vaccine. We collected data on COVID-19 clinical presentation, laboratory examinations, and outcomes. ResultsGroup 1 was constituted of 44 patients (69.3{+/-}14.6 years) and Group 2 of 55 patients (67.4{+/-}15.3 years). Among Group 2, fifty-two patients (95%) were vaccinated, 43 of them (83%) with three doses. Patients of Group 2, compared with Group 1, were more often asymptomatic (38 vs 10%, p=0.002), and reported less frequent fever and pulmonary involvement. At diagnosis, the Group 2 showed a significantly higher number of lymphocytes (0.97{+/-}0.45 vs 0.69{+/-}0.35 cells x109/L, p=0.008) and lower levels of circulating IL-6 (16{+/-}13.3 vs 41{+/-}39.4 pg/ml, p=0.002). Moreover, in Group 2, inflammatory parameters significantly improved after a few days from diagnosis. Patients of Group 2 presented a lower hospitalization rate (12.7 vs 38%, p=0.004), illness duration (18.8{+/-}7.7 vs 29.2{+/-}19.5 days, p=0.005), and mortality rate (5.4 vs 25%, p= 0.008). Finally, responders to the vaccination (80% of the vaccinated patients) compared with non-responders showed a reduction in infection duration and hospitalization (5 vs 40%, p=0.018). ConclusionsCOVID-19 presentation and course in HD patients have improved over time after the implementation of vaccine campaigns. However, due to the evolving nature of the disease, active surveillance is necessary.
