A Study on Mortality Predictors in Hemodialysis Patients Infected with COVID-19: Impact of Vaccination Status

Abstract

The global outbreak of COVID-19, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has prompted significant public health concerns. This study focuses on 442 chronic hemodialysis patients diagnosed with COVID-19, emphasizing the impact of vaccination status on clinical outcomes. The study investigates the correlation between vaccination status and laboratory findings, aiming to identify predictive factors for mortality. Results indicate that vaccination status plays a crucial role in outcomes. Full vaccination, evidenced by two or three doses, is associated with better outcomes, including reduced incidence of bilateral pneumonia and lower risks of complications such as hemorrhage and thrombosis. Laboratory analyses reveal significant differences between vaccinated and unvaccinated patients in parameters like C-reactive protein, ferritin, and white blood cell counts. Univariate and multivariate Cox proportional hazards regression analyses identify several factors influencing mortality, including comorbidities, pneumonia development, and various inflammatory markers. In conclusion among hemodialysis patients affected by COVID-19 infection, vaccination with at least three doses emerges as a protective factor against fatal outcomes. Independent predictors of mortality are CRP levels upon admission, maximum CRP values during the illness and cardiovascular comorbidities. Noteworthy lymphocytopenia during infection exhibits a notable level of specificity and sensitivity in predicting mortality.

Keywords: COVID-19; chronic kidney disease; hemodialysis; lymphocytopenia; vaccines.

Figure 1

Schematic layout of study protocol, point by point.

Figure 2

Distribution of patients based on the type and number of received vaccines.

Figure 3

Kaplan–Meier curve survival analysis according to the number of received vaccine doses whereas unvaccinated vs. 3 doses p = 0.001, 2 doses vs. 3 doses p = 0.009.

Figure 4

The ROC curve of the discriminative ability of the minimum number of lymphocytes during hospitalization in predicting mortality: (A) represents all admission patients to the hospital (n = 442), (B) represents unvaccinated patients (n = 173), (C) represents patients who received two doses of the vaccine (n = 112) and (D) represents fully vaccinated patients with three doses of the vaccine (n = 138).

Figure 4

The ROC curve of the discriminative ability of the minimum number of lymphocytes during hospitalization in predicting mortality: (A) represents all admission patients to the hospital (n = 442), (B) represents unvaccinated patients (n = 173), (C) represents patients who received two doses of the vaccine (n = 112) and (D) represents fully vaccinated patients with three doses of the vaccine (n = 138).

Figure 5

ROC curve of the discriminative ability of CRP values in predicting mortality: (A) represents all admission patients to the hospital (n = 442), (B) represents unvaccinated patients (n = 173), (C) represents patients who received two doses of the vaccine (n = 112) and (D) represents fully vaccinated patients with three doses of the vaccine (n = 138).

Figure 5

ROC curve of the discriminative ability of CRP values in predicting mortality: (A) represents all admission patients to the hospital (n = 442), (B) represents unvaccinated patients (n = 173), (C) represents patients who received two doses of the vaccine (n = 112) and (D) represents fully vaccinated patients with three doses of the vaccine (n = 138).