Prevalence of self-reported diabetes and diabetic retinopathy in indigenous Australians: the National Indigenous Eye Health Survey

Background: To assess the prevalence of diabetes and diabetic retinopathy in indigenous Australians aged ≥40 years.

Design: The National Indigenous Eye Health Survey used a stratified, multistage cluster probability sampling frame to provide a representative sample of the indigenous Australian population.

Participants: One thousand one hundred and eighty-nine eligible indigenous adults were examined using standardized procedures.

Methods: Each participant underwent a comprehensive eye examination included presenting and best corrected visual acuity, visual field, fundus and lens photography.

Main outcome measures: Diabetic retinopathy.

Results: The prevalence of diabetes in the 1189 eligible indigenous adults was 37.3% (95% confidence interval: 34.6-40.2%). The prevalence of diabetic retinopathy among 394 people with diabetes was 29.7% (95% confidence interval: 25.2-34.2%), and 17.8% (95% confidence interval: 14.0-21.6%), 8.9% (95% confidence interval: 6.1-11.7%) and 3.1% (95% confidence interval: 1.3-4.7%) for mild or moderate diabetic retinopathy, clinically significant macular oedema and severe or proliferative diabetic retinopathy, respectively. Diabetic retinopathy was presented in 6.3% in those who did not report diabetes. The risk of diabetic retinopathy increased with duration of diabetes (the adjusted odds ratios were 3.4 for 10-19 years, 6.1 for 20-29 years and 25.8 for ≥30 years).

Conclusions: The prevalence of self-reported diabetes in indigenous Australians is more than eight times higher than that in non-indigenous Australians. The prevalence of diabetic retinopathy in people with diabetes is similar to that of non-indigenous Australians.