2.4 Statistical Analysis

All statistical analyses were performed using SPSS Statistics software, version 23.0 (SPSS Inc., Chicago, IL, USA). The Shapiro-Wilk test was first performed to determine the normality of continuous data. Normally distributed variables were recorded as mean ± standard deviation (SD), and Student’s t-tests were applied for comparisons between two groups. These non-normally distributed data were presented as the median with interquartile range (IQR) and compared using the Mann–Whitney U-test. Categorical variables were expressed as counts with percentages, and the chi-square test or Fisher exact test was used to compare differences between two groups. Comparisons between multiple groups were conducted via one-way analysis of variance with a post hoc Bonferroni correction in cases of equal variance, while the post hoc Tamhane test was used in cases of unequal variance. To explore the diagnostic ability of serum Drp1 and its relationship to the composite endpoint, receiver operating characteristic (ROC) curves were generated, and the optimal cut-off points were identified by the Youden index, respectively. Then, participants were classified into the low and high Drp1 groups based on the optimal cut-off point. Kaplan-Meier (K-M) analysis was utilized for generating the time-to-first event curves in the two groups, and the log-rank test was performed to compare their differences. Binary logistic regression was employed to examine whether serum Drp1 was independently associated with clinical endpoints after adjusting for potential confounding factors. Survival curves and the forest plot showing the results of the binary logistic regression were acquired using GraphPad Prism 8 (GraphPad Software, San Diego, CA, USA). A p value 0.05 was considered as statistically significant, and all p values were two tailed.