Statistical Analysis:
Categorical variables were presented as absolute numbers with
percentages. Their distributions were compared between the groups with
the chi-square test if its assumptions were met. Otherwise, we used
Fisher’s exact test. Due to skewed distributions, all continuous
variables were presented as median values with quartiles in brackets. We
compared their distributions between the groups with the Mann-Whitney
test. The survival analysis was made with the use of the Kaplan-Meier
method. Using Cox regression models and calculating hazard ratios and
95% confidence intervals, analyses of data were conducted to identify
risk factors for mortality in 30 days and 5 years. The survival
functions of the analyzed groups were compared with the log-rank test.
Overall, p-values <0.05 were considered statistically
significant. For the statistical analysis, we used the R software v.
4.0.3. (Foundation for Statistical Computing, Vienna, Austria), as well
as IBM SPSS v. 27.0.