Trends in ischaemic heart disease: patterns of hospitalisation and mortality rates differ by ethnicity (ANZACS-QI 21).

AIM: To examine trends in ischaemic heart disease (IHD) events by ethnicity. METHODS: All IHD deaths and hospitalisations from 2006-2015 were identified using individual-linkage of national hospitalisation and mortality data. Age-standardised IHD rates and average annual age-adjusted percent changes were estimated by ethnic group. Ratios of non-fatal to fatal events were calculated by dividing age-standardised hospitalisation by death rates. RESULTS: IHD mortality rates declined by 3.1-5.4% per year for most groups, except Pacific women, who experienced a non-significant decline of 1.3% per year. IHD hospitalisation rates declined significantly by 3.6-8.8% per year in all groups. IHD mortality rates were highest in Maori and Pacific people, but hospitalisation rates highest in Indians. Indians also had the highest ratio of hospitalisations to deaths. For every person who died from IHD in 2014/15, 7-8 Indians, but only 3-4 Maori or Pacific people, were hospitalised with IHD. CONCLUSION: Fatal and non-fatal IHD rates are declining in all groups, but Maori and Pacific people have disproportionately high rates of IHD mortality. The much lower ratio of IHD hospitalisations to deaths among Maori and Pacific people compared to others suggests there are still important barriers to preventive interventions and acute care for Maori and Pacific men and women.

Ethnic differences in case fatality following an acute ischaemic heart disease event in New Zealand: ANZACS-QI 13.

BACKGROUND: The aim of this study was to investigate ischaemic heart disease (IHD) case fatality in high-risk ethnic populations in New Zealand. DESIGN: This is a national data-linkage study using anonymised hospitalisation and mortality data. METHODS: Linked individual patient data were used to identify 35-84-year-olds who experienced IHD events (acute IHD hospitalisations and/or deaths) in 2009-2010. Subjects were classified as: (i) hospitalised with IHD and alive at 28 days post-event; (ii) hospitalised with IHD and died within 28 days; (iii) hospitalised with a non-IHD diagnosis and died from IHD within 28 days; or (iv) died from IHD but not hospitalised. Multinomial logistic regression was used to estimate the proportion of people in each group, as well as overall 28-day case fatality, adjusted for ethnic differences in demographic and comorbidity profiles. RESULTS: A total of 26,885 people experienced IHD events (11.3% Maori, 4.0% Pacific and 2.5% Indian); 3.3% of people died within 28 days of IHD hospitalisations, 5.1% died of IHD within 28 days of non-IHD hospitalisations and 13.0% died of IHD without any recent hospitalisation. Overall adjusted case fatality was 12.6% in Indian, 20.5% in European, 26.0% in Pacific and 27.6% in Maori people. Compared to Europeans, the adjusted odds of death were approximately 50% higher in Maori and Pacific people and 50% lower in Indians, regardless of whether they were hospitalised. CONCLUSIONS: Major ethnic inequalities in IHD case fatality occur with and without associated hospitalisations. Improvements in both primary prevention and hospital care will be required to reduce inequalities.

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.