Falling hospital and postdischarge mortality following CABG in New South Wales from 2000 to 2013

OBJECTIVES: To describe changes in mortality among patients undergoing coronary artery bypass grafting (CABG) in New South Wales (NSW) Australia from 2000 to 2013. METHODS: Patients undergoing CABG were identified from the NSW Admission Patient Data Collection (APDC) registry, linked to the NSW state-wide death registry database. Changes in all-cause mortality over time were observed following stratification of the study cohort into two year groups. RESULTS: We identified 54 767 patients undergoing CABG during the study period. The risk profile of patients increased over time with significant increases in age, comorbidities and concomitant valve surgery (all p < 0.0001). During a median follow-up period of 6 years, a total 12 161 (22.2%) of patients had died. Survival curves and adjusted analyses showed a steady fall in mortality rate: those operated on during 2012–2013 had 40 % lower mortality than those operated on during 2000–2001 (HR 0.61; 95% CI 0.53 to 0.69). This was contributed to both by a fall in mortality both in hospital (HR 0.48, 95% CI 0.37 to 0.62) and postdischarge (HR 0.73; 95% CI 0.61 to 0.86). CONCLUSIONS: We report a consistent reduction in medium-term mortality among a large unselected cohort of NSW patients undergoing CABG between 2000 and 2013. This fall is attributable both to an improvement in outcomes in hospital and in the postdischarge period.