DISCUSSION
Our analysis confirmed that the risk group for a severe course of
COVID-19 infection, as well as for death, are patients over 59 years,
diabetes mellitus was found to be an independent risk factor for
hospital admission. Our data correspond with the conclusions of the
ERACODA register in which a 28-day mortality was primarily associated
with elderly kidney transplant patients (5). An analysis by French
authors comparing the course of COVID-19 infection in patients after
kidney transplantation with a non-transplant group also confirmed the
significantly worse outcome of COVID-19 in the group of transplant
patients over 60 years of age (19). Diabetes mellitus was confirmed as
an independent risk factor for a serious course of COVID-19 in the group
of patients after kidney transplantation (21). Advanced impairment of
graft function at the time of infection was identified as another risk
factor for poor outcome in the studied group of patients. The prevalence
of the alpha variant in Slovakia did not affect the development of
morbidity and mortality in patients after kidney transplantation.
The pandemic heavily impacted both the dialysis care and organ
procurement and transplantation activities: hemodialysis centers became
a source of infections owing to the model of repetitive treatment in a
closed community; peritoneal dialysis insertions which could have
protected CKD patients as they allow dialysis outside the hospital were
postponed as non-urgent procedures (4, 15).
These factors also affected the situation in Slovakia. A quick
understanding that restricting or stopping kidney transplants from
deceased and living donors could lead to unnecessary deaths of the
waitlisted patients led to setting the rules so that the procurement and
transplantation program in Slovakia did not stop during the second wave
of the COVID-19 crisis. Claims that transplant patients are at a high
risk of infection and it is better to keep them on the hemodialysis
program have proved to be unsubstantiated. All the more so, given that
the morbidity and mortality of patients in hemodialysis centers in
Slovakia was 52% and 30%, which was a higher rate compared to the
ERA-EDTA Registry (7) and the ERACODA database (5) data, where 28-day
mortality was 19.9% and 25%. The onset of morbidity and mortality in
Slovakia during the second wave of the COVID-19 pandemic was also
reflected in the increase in the number of infected KTRs, but compared
to the hemodialysis population, the risk of infection and death was 3.7
times lower. According to the data of ERA-EDTA a EU National Competent
Authorities on Organ donation and transplantation the risk of being
infected by SARS-CoV-2 was more than 4 times lower for kidney transplant
recipients than for hemodialysis patients, mainly because transplant
patients can be managed at home, while hemodialysis still takes place
mostly in hospital settings (4, 17). It should be noted that
hemodialysis patients are generally older and have a higher prevalence
of comorbid conditions than kidney transplant recipients (16). At the
Slovak hemodialysis units, screening for COVID-19 was performed not only
in symptomatic patients and as a post-contact screening, but also as a
part of routine surveillance, whereas transplant patients only underwent
testing when they presented with symptoms or after the contact with a
positive person. On the other hand, lower morbidity and mortality among
transplant patients may be explained by better habits to protect oneself
from infection and by better opportunities to manage the treatment at
home and remotely during the critical period of the pandemic
(telemedicine, e-prescription), while hemodialysis still mostly takes
place in hospital settings. Therefore, promoting transplantation is
integral to fostering future preparedness for other mass infectious
disease emergencies (4).
Unlike the first wave, the second wave in Slovakia was marked by slow
enacting of the precautions, greater benevolence, misinterpretation of
negative test results (as being a ”freedom pass”) and also pandemic
fatigue. Nevertheless, Slovakia was able to maintain the procurement and
transplantation program. While donation and organ transplants in some
European Union countries dropped by more than 80% (7), in Slovakia it
was only up to 33.5%. Kidney transplants from living donors, with the
exception of the first wave, continued without restriction and at the
same level as in 2018 and 2019. No transmission of infection from the
donor to the recipient or infection in the hospital during the short
post-transplant period was observed. The first wave of the COVID-19
pandemic in Slovakia has shown that clear rules and strict anti-epidemic
measures and their observance by kidney transplant patients as well as
their family members are an efficient way to protect against the
disease. Increased vigilance during a pandemic and the prevention of
infectious diseases should be maintained not only shortly after
transplantation, but also later, as patients being longer
post-transplantation became infected more frequently (median: 5.7
years).
In January 2021, vaccination started in Slovakia for health
professionals and at-risk groups of the population, including patients
with CKD, especially patients on dialysis and transplant patients.
The limitation of our analysis lies in the absence of data regarding the
treatment of patients during hospitalization, since the patients were
not hospitalised in a specialized COVID-19 center, consultation timing
varied and thus, the treatment data would not be homogeneous. On the
other hand, our analysis deals with the risk factors for a severe course
of COVID-19 before the infection onset.