Abstract
OBJECTIVES: To characterise diabetic macular atrophy (DMA) and identify risk factors for progression to retinal pigment epithelium (RPE) and outer retinal atrophy. METHODS: In this retrospective longitudinal cohort study, we analysed 103 eyes from 70 patients with diabetic retinopathy (DR) and DMA, identified between 2015 and 2024. DMA was defined by clear-bordered hypopigmented RPE lesions on fundus photography with corresponding choroidal hypertransmission on optical coherence tomography (OCT). Lesions were classified as focal or diffuse and staged using modified criteria from the Classification of Atrophy Meetings for the geographic atrophy. Longitudinal OCT, fundus photos, and visual acuity were evaluated using time-to-event analysis and linear mixed-effects models. RESULTS: Over a mean follow-up of 91.9 months, 93% of eyes progressed to complete RPE and outer retinal atrophy (cRORA). Foveal detachment from DR-related macular structural complications, including macular oedema, epiretinal membrane, vitreomacular traction, and retinal detachment, was linked to earlier onset (p < 0.001) and faster progression (p = 0.036) to cRORA. Diffuse-type DMA, more common in females and eyes post-vitrectomy with silicone oil, was associated with worse visual acuity throughout progression (p = 0.010) and at end-stage (p = 0.029). Fundus autofluorescence in DMA revealed a characteristic diffuse hypoautofluorescence surrounding atrophic patch. CONCLUSION: DMA is a vision-threatening, progressive condition in advanced DR. The diffuse-type DMA predicted worse vision throughout DMA progression and end-stage DMA. Foveal detachment of any cause was associated with earlier DMA onset and faster progression to end-stage. Structural macular complications in DR may play a pivotal role in DMA pathogenesis.