Ethnic Differences in Coronary Revascularisation following an Acute Coronary Syndrome in New Zealand: A National Data-linkage Study (ANZACS-QI 12)

Background The aim of this study was to describe ethnic differences in angiography and revascularisation rates following an acute coronary syndrome (ACS) in New Zealand. Methods National hospitalisation and mortality data were anonymously linked to determine receipt of angiography and revascularisation for 30-84 year-olds hospitalised with ACS between 2007 and 2012. Multilevel Cox regression, accounting for individual factors and admitting hospital, was used to estimate adjusted procedural rates within 30 days of admission. Results Of the 50,324 ACS patients included, 10% were Maori, 4% Pacific, 3% Indian and 83% New Zealand European or Other ethnicities (NZEO). A larger proportion of Maori (48%) than NZEO (36%), Pacific (19%) and Indian (14%) patients were admitted to hospitals without catheterisation facilities. More Maori and Pacific (22-24%) than NZEO and Indian patients (12-13%) had severe comorbidities. Maori and Pacific were less likely than NZEO patients to receive angiography (adjusted HRs 0.94 [0.91-0.98] and 0.93 [0.87-0.98] respectively) and revascularisation (adjusted HRs 0.79 [0.75-0.83] and 0.77 [0.71-0.83]), even after adjusting for important demographic and clinical factors. Conclusions A higher comorbidity burden in Maori and Pacific patients and reduced access to catheterisation facilities for non-urban Maori contributed to lower procedure rates after ACS admission. Ethnic differences remained after adjustment for these factors and require further investigation.