Statistical Analysis
Comparisons between groups were performed by the t -test or
Mann-Whitney U test when necessary. Categorical variables are expressed
as frequencies and percentages and were compared with the χ2 test and
Fisher’s exact test when appropriate. A Cox proportional hazard analysis
was used to calculate the hazard ratios (HRs) and investigate the risk
factors for aorta-related mortality. In the multivariate Cox
proportional hazard models, the entry and removal criteria were set atP =0.05 and P =0.20. Kaplan-Meier survival analysis with the
log-rank test was used to estimate the cumulative mortality and
aortic-related mortality in different groups. We used the
Kolmogorov–Smirnov test to evaluate the normality of the continuous
variables. Differences with P values <0.05
were considered statistically significant. IBM SPSS for Windows version
26.0 (IBM Corp, Armonk, New York) was used for statistical analysis.