<div>DISCUSSION</div><div>In the study, age, chronic illness, length of stay and biochemical blood
parameters of the patients were evaluated separately and their effects
on the risk of death were investigated. In our study, the mortality rate
of patients ≥65 was found to be higher. Similarly, Ergenc et al. (21)
found that patients with ≥65 deaths had a higher mortality rate. In the
study of Teker et al. (22), found that the course of COVID-19 disease
worsened with age and deaths increased. . Unver-Ulusoy et al. (23) found
that 68.8% of the patients hospitalized in the intensive care unit were
65 years and older. According to the information reported by the US
Centers for Disease Control and Prevention (CDC), the mortality rate
observed in ≥65 patients is higher (24). It is thought that weakened
immune functions in elderly patients predispose to infection (25).
Therefore, it is thought that the mortality rate may be higher in
patients over 65.</div><div>In our study, it is seen that the mortality rate is higher in patients
with chronic diseases. Wang et al. (26) reported that elderly people are
at higher risk for chronic diseases and infections, and that mortality
due to COVID-19 increases in those with hypertension and coronary heart
disease. Reyes-Sánchez et al. (27) in his study on adults who tested
positive for COVID-19 in Mexico, revealed that chronic diseases may be
associated with the severity of COVID-19 and deaths. Considering the
information in the literature, it is seen that the state of chronic
illness can be used as a leading parameter in estimating the course of
the disease.</div><div>In our study, it was concluded that the risk of death from COVID-19 did
not differ significantly by gender. However, it is seen that there are
different results in the literature. The effect of gender on the risk of
COVID-19 and death was investigated by Doerre and Doblhammer (28). In
the study, it was determined that the mortality rate in men was 2 times
higher than that in women. Unver-Ulusoy et al. (23) found that men have
a higher risk of death. Peckham et al. (29) found that male patients
were almost three times more likely to be admitted to the intensive care
unit than females and had higher mortality rates. Considering the
results in the literature, it can be said that men are in the
disadvantaged group in deaths caused by COVID-19.</div><div>The hospitalization time of the patients who died was found to be
higher. According to Rozman et al. (30), the probability of being
discharged within the first 7 days after hospitalization was 36.5%,
while the probability of dying in the same period was 7.9%. On the 21st
day, the probability of being discharged increased to 72.9%, while the
probability of death increased to 14.4%. da Costa Sousa et al. (31)
revealed that a longer hospital stay may be related to age. More
comprehensive studies are needed to explain the relationship between
length of stay and death.</div><div>In our study, the diagnostic power of biochemical blood parameters of
COVID-19 patients was investigated. Among the biochemical parameters
included in the study, the AUC values of Urea, LDH, Albumin and CRP were
found to be high (0.8-0.9). Among these parameters, the highest AUC
value belongs to CRP. Logistic regression analysis was performed to
understand the effect of biochemical parameters on the risk of death.
The increase in Glucose, Urea, ALP and LDH values increased the risk of
death; It was observed that the increase in Albumin, Calcium and
Potassium values decreased the risk of death. In the study of Ergenç et
al. (21), WBC, procalcitonin, troponin, ferritin, monocytes, INR, LDH,
AST, ALT, MVC and PLT values were found to be higher in the old ex.
Ferrari et al. (32) stated that simple hematological tests can be used
in the diagnosis of COVID-19 in developing countries where RT-PCR
testing is limited.</div><div>Strength and Limitation of the Study</div><div>The biggest strength of this study is the high sample size and the use
of various biochemical blood values.</div><div>The major limitation of this study is that it is a retrospective study
with its own limitations.</div><div>Conflict of Interest</div><div>There is no conflict of interest</div><div>Financial Support</div><div>No financial support</div><div>Patient Consent</div><div>It is a study that does not require patient consent.</div><div>REFERENCES</div><div>1. Lippi G, Sanchis-Gomar F, Henry BM. Coronavirus disease 2019
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