Coronary heart disease events in Aboriginal Australians: incidence in an urban population

Objective: To determine the incidence of coronary heart disease (CHD) events in an urban Aboriginal population. Design, setting and participants: Cohort study of 906 Aboriginal people without CHD from 998 who had undergone risk-factor assessment in the Perth Aboriginal Atherosclerosis Risk Study (PAARS) in 1998-1999. PAARS cohort data were electronically linked to a range of databases that included Western Australian hospital morbidity data and death registry data. We analysed data from January 1980 to December 2006 to identify previous admissions for CHID from 1980 to baseline (1998-1999) and new events from baseline to 2006. Main outcome measure: First CHD event (hospital admission or death). Results: There were 891 linked records for the 906 participants without previous CHD. The event rate was 12.6/1000 person-years (95% Cl, 10.2-15.6/1000 person-years). Annual CHD event rates ranged from 8 to 18/1000 person-years. After adjustment for age (sex was not associated with the risk factors assessed), factors associated with risk of a CHID event in the PAARS cohort were a history of diabetes, overweight or obesity (indicated by body mass index), smoking, and hypertension, but not waist circumference. People with these risk factors were 1.9-2.7 times more likely to experience a CHID event. Compared with previously published information from a remote Aboriginal community in the Northern Territory, the incidence of CHID events among urban-dwelling Aboriginal people was not significantly different (P>0.05 overall and for subgroups defined by age and sex). Conclusions: City-dwelling Aboriginal Australians have an incidence of CHID events comparable to that of Aboriginal people living in remote northern Australia. MJA 2009; 190: 583-586