Screening for Diabetic Eye Disease among Samoan Adults: A Pilot Study

Introduction: The purpose of this study was to determine the prevalence of diabetic retinopathy in Samoa by piloting a retinal photography screening programme.

Methods: We performed a cross-sectional study of patients with diabetes who presented to the Tupua Tamasese Meaole eye clinic in Apia, Samoa, between May 2011 and September 2011. Study approval was granted by the National Health Service Board of Samoa, the Monash University Human Research Ethics Committee, and the study adhered to the Tenets of the Declaration of Helsinki. Following informed consent, data collection included patient demographics [age, area of residence (rural or urban)], type of diabetes, length of time since diagnosis, most recent random blood sugar and blood pressure levels. The subjects had three 45-degree retinal photographs taken in each eye with the Canon CR6-45NM camera. All gradable photographs were assessed for the presence of diabetic retinopathy or macular oedema using the International Clinical Diabetic Retinopathy Severity Scale and the International Clinical Diabetic Macular Oedema Severity scale, respectively.

Results: Two hundred and fourteen eyes from 107 subjects were examined during the study period, all of whom had type 2 diabetes mellitus. Diabetic retinopathy was present in 53.3% (114/214) of eyes, with 14.5% having proliferative retinopathy and 7.5% with severe non-proliferative retinopathy. Also, 25.2% (54/214) had some evidence of macular oedema with 11.7% (25/214) requiring treatment. A statistically significant relationship existed between the length of time since diagnosis and the severity of both retinopathy (p < 0.001) and macular oedema (p = 0.031). Blood pressure more than 150/85 mmHg was associated with higher levels of diabetic retinopathy (p = 0.03) and macular oedema (p = 0.02).

Conclusion: A comprehensive diabetic retinopathy screening programme is much needed in Samoa given the high prevalence of diabetic eye disease.