Statistics

Statistical analyses were performed using GraphPad Prism 8 (GraphPad Software Inc., San Diego, CA) and SPSS 19 for Windows (SPSS Inc., Chicago, IL). Discrete variables are expressed as numbers and percentages. Quantitative variables with a normal distribution are expressed as the means ± standard deviations. Quantitative variables with a skewed distribution are expressed as the medians and interquartile ranges (IQRs). The data were compared between groups using a student's test or a nonparametric test. The chi-squared test was used to compare categorical data. The relationships between the expression levels of PAI-1 and other inflammatory biomarkers were assessed by bivariate correlation analysis.