Statistical Analysis
Comparisons between groups were performed by the t -test or
Mann-Whitney U test when necessary. Categorical variables are expressed
as a frequency and a percentage 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 of aorta-related mortality. In the multivariate Cox proportional
hazard models, the entry and removal criteria were set at P =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.