Association between preoperative hyperglycemia and adverse cardiac events after non-cardiac surgery: a multicenter cohort study

Fig. 1.. Study flowchart of patients with and without adverse cardiac events after non-cardiac surgery. We began with de-identified data for 12 024 817 patients in Korea’s standardized EMR database and extracted the records of 318 119 adult patients (> 18 years) who underwent surgery, had available medical records for more than 180 days before surgery, and had at least one blood glucose measurement from less than 24 hours prior to surgery. After 1:2 PSM, 40 340 patients with hyperglycemia and 70 770 with normoglycemia were matched. EMR: electronic medical records, PSM: propensity core matching, AUMC: Ajou University Medical Center, KHMC: Kyung Hee University Hospital, KDH: Kangdong Sacred Heart Hospital, GNUH: Gyeongsang National University Hospital, EUMC: Ewha Womans University Medical Center, KWMC: Kangwon National University Hospital, SCHBC: Soonchunhyang University Bucheon Hospital, SCHCA: Soonchunhyang University Cheonan Hospital, SCHGM: Soonchunhyang University Gumi Hospital, SCHSU: Soonchunhyang University Seoul Hospital.

Fig. 2.. (A) A graphical representation of the PSM used in this study. The x-axis of the plot represents the preference scores that estimate the likelihood of treatment based on observed characteristics. The y-axis represents density, indicating the concentration or distribution of data points. When the data points of the treated and control groups overlap, it suggests that individuals with similar propensity scores have been successfully matched. (B) Covariate balance plot before and after PSM across 10 hospitals. After PSM, we plotted the ASD of the covariates to validate the adequacy of matching, and most of the ASDs were < 0.1 that shows that matching was balanced and adequate. PSM: propensity score matching, ASD absolute standardized difference.

Fig. 3.. Forest plot representing the meta-analysis results for the risk of adverse cardiac events within one year after non-cardiac surgery in patients with acute hyperglycemia across 10 hospitals. The HRs and 95% CIs are indicated by the diamond shapes for the combined effect estimate and by the squares for each individual study. The size of the square represents the weight of each study. The horizontal line represents the 95% CI, and the diamond shape represents the overall pooled effect estimate. The four numbers within each column represent the number of patients with acute hyperglycemia with the outcome and without it and the number of patients with normoglycemia with the outcome and without it. HR: hazard ratio, AUMC: Ajou University Medical Center, EUMC: Ewha Womans University Medical Center, GNUH: Gyeongsang National University Hospital, KDH: Kangdong Sacred Heart Hospital, KHMC: Kyung Hee University Hospital, KWMC: Kangwon National University Hospital, SCHBC: Soonchunhyang University Bucheon Hospital, SCHCA: Soonchunhyang University Cheonan Hospital, SCHGM: Soonchunhyang University Gumi Hospital, SCHSU: Soonchunhyang University Seoul Hospital.

Fig. 4.. This figure shows a one-year plot of survival across the 10 hospitals. Each KM plot shows the cumulative incidence of adverse cardiac events after non-cardiac surgery, defined as a composite of myocardial infarction, coronary revascularization, congestive heart failure, arrhythmic attack, acute pulmonary embolism, cardiac arrest, and stroke. The P value was calculated using the log-rank test. The insets show the same data on enlarged y-axes. KM: Kaplan Meier, EMR: electronic medical records, PSM: propensity core matching, AUMC: Ajou University Medical Center, KHMC: Kyung Hee University Hospital, KDH: Kangdong Sacred Heart Hospital, GNUH: Gyeongsang National University Hospital, EUMC: Ewha Womans University Medical Center, KWMC: Kangwon National University Hospital, SCHBC: Soonchunhyang University Bucheon Hospital, SCHCA: Soonchunhyang University Cheonan Hospital, SCHGM: Soonchunhyang University Gumi Hospital, SCHSU: Soonchunhyang University Seoul Hospital, PSM: propensity core matching, ASD: absolute standardized difference, HR: hazard ratio, KM: Kaplan Meier.