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Objective: To estimate coronary heart disease (CHD) incidence, prevalence, survival, case fatality and mortality for Maori, in order to support service planning and resource allocation. Methods: Incidence was defined as first occurrence of a major coronary event, i.e. the sum of first CHD hospital admissions and out-of-hospital CHD deaths in people without a hospital admission for CHD in the preceding five years. Data for the years 2000-02 were sourced from the New Zealand Health Information Service and record linkage was carried out using a unique national identifier, the national health index. Results: Compared to the non-Maori population, Maori had both elevated CHD incidence and higher case fatality. Median age at onset of CHD was younger for Maori, reflecting both higher age specific risks and younger population age structure. The lifetable risk of CHD for Maori was estimated at 37% (males) and 34% (females), only moderately higher than the corresponding estimates for the non-Maori population, despite higher Maori CHD incidence. This reflects the offsetting effect of the higher 'other cause' mortality experienced by Maori. Median duration of survival with CHD was similar to that of the non-Maori population for Maori males but longer for Maori females, which is most likely related to the earlier age of onset. Conclusions: This study has generated consistent estimates of CHD incidence, prevalence, survival, case fatality and mortality for Maori in 2000-02. The inequality identified in CHD incidence calls for a renewed effort in primary prevention. The inequality in CHD case fatality calls for improvement in access for Maori to secondary care services. Key words: coronary disease, epidemiology, lifetable, New Zealand, ethnicity. doi: 10.1111/j.1753-6405.2009.00412.x

Objective: To estimate the contribution of trends in three risk factors--systolic blood pressure (SBP), total blood cholesterol (TBC) and cigarette smoking--to the decline in premature coronary heart disease (CHD) mortality in New Zealand from 1980-2004. Method: Risk factor prevalence data by 10-year age group (35-64 years) and sex was sourced from six national or Auckland regional health surveys and three population censuses (the latter only for smoking). The data were smoothed using two-point moving averages, then further smoothed by fitting quadratic regression equations (SBP and TBC) or splines (smoking). Risk factor/CHD mortality hazard ratios estimated by expert working groups for the World Health Organization Global Burden of Disease Study 2001 were used to translate average annual changes in risk factor prevalences to the corresponding percentage changes in premature CHD mortality. The expected trends in CHD mortality were then compared with the observed trend to estimate the contribution of each risk factor to the decline. Findings: Approximately 80% (73% for males, 87% for females) of the decline in premature CHD mortality from 1980 to 2004 is estimated to have resulted from the joint trends in population SBP and TBC distributions and smoking prevalence. Overall, approximately 42%, 36% and 22% of the joint risk factor effect was contributed by trends in SBP, TBC and smoking respectively. Conclusion: Our estimate for the joint risk factor contribution to the CHD mortality decline of 80% exceeds those of two earlier New Zealand studies, but agrees closely with a similar Australian study. This provides an indicator of the scope that still remains for further reduction in CHD mortality through primary and secondary prevention. Key words: Risk factor, coronary heart disease, New Zealand doi: 10.1111/j.1753-6405.2008.00186.x

Objective: To produce internally consistent estimates of coronary heart disease (CHD) incidence, prevalence, survival and mortality as a decision aid for service planning and resource allocation. Methods: Incidence was defined as first occurrence of a major coronary event, i.e. the sum of first CHD hospital admissions and out-of-hospital CHD deaths without a hospital admission for CHD in the preceding five years. Mortality was defined as the sum of deaths coded to CHD and deaths coded to related causes but with prior hospitalisation for CHD (in the preceding five years). Data were sourced from the New Zealand Health Information Service and record linkage was carried out using a unique national identifier, the National Health Index (NHI). Given estimates for incidence and mortality, multi-state lifetables were built and estimates for prevalence, survival, lifetable risk, and median age at onset extracted. Results: Estimated prevalence of CHD increased exponentially from around 2% for males and 0.5% for females at age 40-44 to peak at around 18% and 12% respectively at age 85-89. Median age at onset of CHD was 67.5 years for males and 77.5 years for females. Median survival duration was 9.5 years for males and 6.2 years for females. The lifetable risk of CHD was estimated at 35% for males and 28% for females. Conclusions: This study provides a complete and internally consistent picture of the descriptive epidemiology of CHD for the whole New Zealand population in 2001-03. This information will be useful for planning and funding of coronary prevention, treatment and rehabilitation services. Keywords: Coronary heart disease; incidence; prevalence; mortality; surveillance.