Ethnic Differences in the Distribution of Diabetic Lesions

Abstract

Purpose : Ethnic differences in the prevalence of diabetic retinopathy (DR) have been reported but differences in the DR phenotype have not been well described. In this retrospective study, we evaluate the distribution of DR lesions among various ethnicities.

Methods : We enrolled a cohort of 228 eyes with DR consisting of 49 East Asian eyes (Second Hospital of Tianjin Medical University), 103 South Asian eyes (Narayana Nethralaya Eye Institute), 30 Caucasian eyes (UCLA), and 46 Latino eyes (UCLA) with ultrawidefield images. Both treatment naïve and treated cases were included. Images were manually annotated for DR lesions including microaneurysms, hemorrhages, intraretinal microvascular abnormalities, cotton wool spots, neovascularization, and venous beading. The DR severity was assessed according to the International Clinical Diabetic Retinopathy scale. In accordance with previous publications, eyes were classified as having predominantly peripheral or central lesions (PPL or PCL) based on comparing the frequency of lesions in peripheral fields 3 to 7 versus their respective adjacent ETDRS field 3 to 7 (i.e. >50% of lesions in one or more peripheral fields= PPL). The percent of eyes rated to be PPL were compared among the groups.

Results : The proportion of eyes which featured a PPL distribution was highest in East Asians (85.7%) and lowest in South Asians (35.9%) regardless of prior treatment or DR severity. Among treatment naïve eyes, a total of 39 (84.8%) East Asian eyes, 20 (35.7%) South Asian eyes, 12 (57.1%) Caucasian eyes, and 18 (46.2%) Latino eyes were classified as having PPL. For moderate NPDR, treatment naïve eyes, a PPL distribution was observed in 84.8% of East Asian eyes, 34.9% of South Asian eyes, 38.5% of Caucasian eyes, and 44.4% of Latino eyes. This greater PPL distribution among East Asian eyes was significantly different from South Asian eyes (P<0.0001), Caucasian eyes (P=0.0017), and Latino eyes (P=0.001). East Asian eyes were also more likely to have multiple PPL fields.

Conclusions : The distribution of DR lesions appears to vary among different ethnicities. DR lesions tend to be distributed more peripherally in East Asian eyes compared to other ethnicities, particularly South Asian eyes, which tend to have more central lesions. The prognostic implications of these ethnic differences in DR lesion distribution warrant further study.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.

 

The distribution of DR lesions appears to vary among different ethnicities