Differences in undergoing cardiac procedures within three months after first myocardial infarction by country of birth in women and men: a Swedish national cohort study.

OBJECTIVE: To examine the relationship between country of birth and the utilization of coronary angiography, percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) after a first-time myocardial infarction (MI).

DESIGN, SETTING AND PATIENTS: 117,494 MI patients of all ages who were admitted to coronary care units between 2001 and 2009 in Sweden were followed-up for three months after admission.

MAIN OUTCOME MEASURES: Undergoing coronary angiography, PCI or CABG after first-time MI.

RESULTS: proportion of patients undergoing angiography and PCI increased whereas proportion of patients undergoing CABG also delay time for all three procedures decreased over the study period. The proportion of women undergoing any of the three procedures was markedly lower and delay time longer than those of men regardless of study period and migration background. Overall foreign-born first MI patients had higher rate of angiography (HR = 1.30, 95% CI: 1.27-1.33), PCI (HR = 1.27, 95% CI: 1.24-1.30) and CABG (HR = 1.21, 95% CI: 1.15-1.28) compared with Sweden born first MI patients. After controlling for potential confounding factors in multivariable models, the overall differences vanished for angiography and reduced markedly for PCI and CABG. However, multivariable stratified analysis by specific country of birth yielded higher rate of angiography among men born in Uganda (HR = 2.11, 95% CI: 1.00-4.43) and Peru (HR = 1.98, 95% CI: 1.07-3.68) and lower rate among men born in Croatia (HR = 0.71, 95% CI: 0.52-0.99) and women born in Thailand (HR = 0.49, 95% CI: 0.35-0.94). PCI adjusted rates were higher among women born in Palestine state (HR = 2.44, 95% CI: 1.15-5.16), Iraq (HR = 1.34, 95% CI: 1.04-1.74) and Poland (HR = 1.21, 95% CI: 1.02-1.44) and rate of CABG was higher among immigrants from some parts of Asia, including men born in Sri Lanka (HR = 3.19, 95% CI: 1.43-7.12), India (HR = 1.95, 95% CI: 1.21-3.14), Vietnam (HR = 2.65, 95% CI: 1.32-5.33), Palestine State (HR = 2.11, 95% CI: 1.06-4.24), and women born in Syria (HR = 2.36, 95% CI: 1.25-4.45), Iraq (HR = 1.74, 95% CI: 1.02-2.94), and Turkey (HR = 1.70, 95% CI: 1.03-2.79).

CONCLUSIONS: The observed high rate of CABG for immigrants and particularly those born in some Asian countries was not explained by the potential confounding factors. A more severe coronary disease in this population might explain this high rate but needs further research. Awareness and subsequent intervention at earlier stage of coronary disease among immigrants could prolong their life and reduce the healthcare costs.