Results:
OF the total 106 COVID-19 patients who entered the study, 69 cases were
discharged from the hospital alive while the other 37 cases died. The
mean age of the patients was 58.99±15.94 years and 56.6% of them were
male. Moreover, the patients’ average length of stay in hospital was
11.79±8.22 days. Based on the disease outcome, the patients were divided
into two groups: the survived and the deceased (Table 1). The
demographic information and comorbidities of each group of the patients
are represented in Table 1.
The results showed a significant difference between the two groups in
terms of D-dimer, LDH, PT, and INR levels. However, in terms of
hemoglobin level and platelet count, the differences between the two
groups were not found to be statistically significant. More
specifically, serum D-dimer level, LDH, PT, and INR in the deceased
patients were significantly higher than those of the surviving patients
(Table 2).
In order to determine the relationship between mortality and the
variables under investigation, binary logistic regression was applied on
the data, the result of which are presented in Table 3 below. As can be
seen, the results indicated that serum D-dimer level had a significant
effect on predicting mortality in a way that for each unit of increase
in D-dimer level, mortality risk increased by 0.99% (OR=0.994; 95%CI:
0.992-0.997). In order to determine the cutoff point of serum D-dimer
level for the prediction of mortality, Receiver Operating Characteristic
(ROC) curve was used. Figure 1 shows the related ROC curve. The area
under the ROC curve was obtained to be 85% for D-dimer. Then, based on
the figure, its cutoff point was determined to be 450 μg/dL with the
sensitivity of 98% and specificity of 97%.