β-Blockade in Rectal Cancer Surgery

OBJECTIVE: To ascertain whether regular β-blocker exposure can improve short- and long-term outcomes after rectal cancer surgery. BACKGROUND: Surgery for rectal cancer is associated with substantial morbidity and mortality. There is increasing evidence to suggest that there is a survival benefit in patients exposed to β-blockers undergoing non-cardiac surgery. Studies investigating the effects on outcomes in patients subjected to surgery for rectal cancer are lacking. METHODS: All adult patients undergoing elective abdominal resection for rectal cancer over a 10-year period were recruited from the prospectively collected Swedish Colorectal Cancer Registry. Patients were subdivided according to preoperative β-blocker exposure status. Outcomes of interest were 30-day complications, 30-day cause-specific mortality, and 1-year all-cause mortality. The association between β-blocker use and outcomes were analyzed using Poisson regression model with robust standard errors for 30-day complications and cause-specific mortality. One-year survival was assessed using Cox proportional hazards regression model. RESULTS: A total of 11,966 patients were included in the current study, of whom 3513 (29.36%) were exposed to regular preoperative β-blockers. A significant decrease in 30-day mortality was detected (incidence rate ratio = 0.06, 95% confidence interval: 0.03-0.13, P < 0.001). Deaths of cardiovascular nature, respiratory origin, sepsis, and multiorgan failure were significantly lower in β-blocker users, as were the incidences in postoperative infection and anastomotic failure. The β-blocker positive group had significantly better survival up to 1 year postoperatively with a risk reduction of 57% (hazard ratio = 0.43, 95% confidence interval: 0.37-0.52, P < 0.001). CONCLUSIONS: Preoperative β-blocker use is strongly associated with improved survival and morbidity after abdominal resection for rectal cancer.