Atrial Fibrillation in Remote Indigenous and Non-Indigenous Individuals Hospitalised in Central Australia.

BACKGROUND: The epidemiology of atrial fibrillation (AF) amongst Indigenous populations remains poorly characterised. We studied hospitalisations for AF in Central Australia, the most populous Indigenous region in the country. METHODS: Patients with a diagnosis of AF admitted to Alice Springs Hospital, the only secondary health care facility and provider of cardiac care in remote Central Australia, were identified from 2006 to 2016. Age and gender-specific hospitalised AF prevalence, comorbidities, and CHA2DS2-VASc scores were ascertained. RESULTS: Of 57,056 admitted patients over the study period, 1,210 (2.1%; 46% Indigenous) had a diagnosis of AF. For Indigenous and non-Indigenous individuals <45 years, hospitalised AF prevalence per 10,000 population was 105 (CI 84-131) and 50 (CI 36-68) in males (ratio=2.10), and 98 (CI 77-123) and 12 (CI 6-23) in females (ratio=7.92), respectively. For Indigenous and non-Indigenous individuals ≥65 years, hospitalised AF prevalence per 10,000 was 1,577 (CI 1,194-2,026) and 2,326 (CI 2,047-2,623) in males (ratio=0.68), and 1,713 (CI 1,395-2,069) and 1,897 (1,623-2,195) in females (ratio=0.90). Indigenous individuals had higher rates of cardiometabolic comorbidities, particularly at younger ages. CHA2DS2-VASc scores were greater in Indigenous individuals, particularly those <45 years (2.5±1.5 versus 0.7±1.1, p<0.001). CONCLUSIONS: The prevalence of hospitalised AF amongst Indigenous people in remote Central Australia was significantly higher than in non-Indigenous individuals, particularly in younger age groups and females. Indigenous individuals with hospitalised AF also had a markedly greater prevalence of cardiometabolic comorbidities and elevated stroke risk. These data suggest that AF may be contributing to the gap in morbidity and mortality experienced by Indigenous Australians.