Risk for all-cause mortality and major adverse cardiovascular events after coronary artery bypass grafting in foreign-born compared to native-born Swedish patients

Background In Sweden, a considerable proportion of patients undergoing coronary artery bypass grafting (CABG) are foreign-born. No previous study has investigated if long-term outcome after CABG differs in foreign-born compared to native-born patients in Sweden. Purpose Compare long-term risks for mortality and morbidity after CABG in foreign-born compared to native-born patients in Sweden. Methods Data from the SWEDEHEART registry and three other mandatory national registries were used to identify all patients that underwent isolated CABG in Sweden from 1992 to 2023 and to collect individual patient data about country of birth, patient characteristics, comorbidities, and social factors. Outcome variables of interest were all-cause mortality, major adverse cardiovascular events (MACE, including cardiovascular mortality, non-procedural myocardial infarction (MI), stroke and the individual components of MACE. Multivariable Cox proportional hazard regression models adjusted for age, sex, comorbidities and social factors were employed. Overall median follow-up time was 11.5 years (interquartile range 6.1-17.4 years). Results In total 131 182 patients (20 025 foreign-born (15.3%) and 111 157 native-born (84.7%) were included. Foreign-born patients were younger (63.8 vs 67.1 years) and had more often diabetes, hypertension, heart failure, depression, and previous MI at baseline. The risk for all-cause mortality (adjusted hazard ratio (aHR) 1.02, 95% CI 0.99-1.05), MACE (aHR 1.03, 95% CI 1.00-1.06), cardiovascular mortality (aHR 0.99, 95% CI 0.95-1.04), and stroke (aHR 1.01, 95% CI 0.96-1.07) did not differ significantly between foreign-born and native-born patients, while foreign-born had an increased risk for non-procedural MI (aHR 1.07 95% CI 1.02-1.13) (figure 1). The risk for all-cause mortality divided by geographical areas showed an increased risk for Nordic patients except Sweden (aHR 1.07, 95% CI 1.02-1.11) and patients from non-EU Europe (aHR 1.08 95% CI 1.00-1.16). Patients from Asia had a reduced risk of all-cause mortality (aHR 0.87, 95% CI 0.80-0.94). Conclusion The long-term risks for all-cause mortality and MACE after CABG did not differ between foreign-born and native-born Swedish patients. However, the risk for all-cause mortality differed between geographic areas.