Prevalence and associations of diabetic retinopathy in indigenous Australians within central Australia: the Central Australian Ocular Health Study

Purpose: To determine the prevalence and associations of diabetic retinopathy (DR) within the indigenous Australian population living in central Australia. Methods: 1884 individuals aged 20 years or older, living in one of 30 remote communities within the statistical local area of 'central Australia' were recruited for this study. This equated to 36% of those aged 20 years or older and 67% of those aged 40 years or older within this district. Participants were recruited as they presented to the eye clinic at each remote community. Following dilated slit-lamp fundoscopy, the amount of DR in participants with diabetes mellitus (DM) was quantified using the Early Treatment of Diabetic Retinopathy Study criteria. The presence of any DR and vision-threatening DR (clinically significant macular oedema and/or proliferative DR) in one or both eyes was presented. Results: Of those with diabetes, 22.2% (25.4% of those aged 40 years or older) had any DR and 7.0% (8.4% of those aged 40 years or older) had vision-threatening DR. Both the presence of any DR and vision-threatening DR were associated with advancing age and HbA1c level, but neither subcategory was associated with sex or self-reported hypertension. Conclusion: Our study has shown similar prevalence rates for DR in indigenous Australians compared with non-indigenous Australians. However, as DM is far more prevalent among indigenous Australians, the proportion of those affected by DR across the population should be considerably higher when compared with non-indigenous Australians.