Chemotherapy and adverse cardiovascular events in colorectal cancer patients undergoing surgical resection.

Background Colorectal cancer patients undergoing surgical resection are at increased short-term risk of post-operative adverse events. However, specific predictors for long-term major adverse cardiac and cerebrovascular events (MACCE) are unclear. We hypothesised that patients who receive chemotherapy are at higher risk of MACCE than those who did not. Methods In this retrospective study, 412 patients who underwent surgical resection for newly diagnosed colorectal cancer from January 2013 to April 2015 were grouped according to chemotherapy status. MACCE was defined as a composite of cardiovascular death, myocardial infarction, stroke, unplanned revascularisation, hospitalisation for heart failure or angina. Predictors of MACCE were identified using competing risks regression, with non-cardiovascular death a competing risk. Results There were 200 patients in the chemotherapy group and 212 patients in the non-chemotherapy group. The overall prevalence of prior cardiovascular disease was 20.9%. Over a median follow-up duration of 5.1 years from diagnosis, the incidence of MACCE was 13.3%. Diabetes mellitus and prior cardiovascular disease were associated with an increased risk of MACCE (subdistribution hazard ratio, 2.56; 95% CI, 1.48-4.42) and 2.38 (95% CI, 1.36-4.18) respectively. The chemotherapy group was associated with a lower risk of MACCE (subdistribution hazard ratio, 0.37; 95% CI, 0.19-0.75) compared to the non-chemotherapy group. Conclusions Amongst colorectal cancer patients undergoing surgical resection, there was a high incidence of MACCE. Diabetes mellitus and prior cardiovascular disease were associated with an increased risk of MACCE. Chemotherapy was associated with a lower risk of MACCE, but further research is required to clarify this association.