A systematic review and meta-analysis of real-world studies evaluating the association between beta-blocker use and postoperative adverse events of carotid endarterectomy

Objective: The objective of this study was to estimate the association of beta-blocker use with postoperative adverse events of carotid endarterectomy (CEA) based on real-world data. Methods: Electronic bibliographic sources (MEDLINE, EMBASE, and CENTRAL) were searched up to April 2021 using a combination of thesaurus and free-text terms to identify the studies about the effect of beta-blockers on outcomes of CEA. The systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. All observational studies and randomized controlled trials investigating the effect of preoperative beta-blockers on the outcomes of CEA were included. Independent extraction of articles by two authors using predefined data fields, including study quality indicators. All pooled analyses were based on a random-effects model. Results: A total of seven observational studies (six case-control studies and one cohort study) were included. Of the three case-control studies that examined the association of beta-blockers with composite postoperative adverse events, two studies including three datasets that totaled 24,161 participants were included in the quantitative synthesis, and the overall results showed a statistically significant association between beta-blocker use and composite postoperative adverse events of CEA (odds ratio [OR], 1.35; 95% confidence interval [CI], 1.15-1.59; P = .0003; I-2 = 13%). Publication bias was not present in the meta-analysis (Egger test showed nonsignificant results: P = .453). Two of the included studies utilized indirect measures of cerebral ischemia: intraoperative electroencephalograph, intraoperative hemodynamic indicators; and found a significant association between beta-blockers and intraoperative cerebral ischemia. Another two studies were included for meta-analysis on the association between beta-blockers and 30-day strokes or death of CEA (OR, 1.61; 95% CI, 0.98-2.65; P = .06; I-2 = 0%). Of all included studies, there was only one cohort study that reported the association of beta-blockers with postoperative myocardial infarction by chi(2) analysis (OR, 1.96; 95% CI, 1.86-2.07). Conclusions: This systematic review suggested that there was an increased risk of postoperative adverse outcomes of CEA among beta-blocker users compared with nonusers in the real world.