Statistical analysis.
Continuous variables following normal distribution were presented as
mean ± standard deviations. Non-normally distributed variables were
presented as median and range. Categorical variables were presented as
counts and percentages. All data were analyzed with SPSS 23.0
statistical software (SPSS23, Chicago, IL, USA). A p -value
of<0.05 was considered statistically significant. A 1-year Kaplan-Meier
estimate of all-cause mortality was calculated for patients.