Myopic macular degeneration in Asians: Who’s at risk?

12 Sep 2020
Myopic macular degeneration in Asians: Who’s at risk?

The risk of developing myopic macular degeneration (MMD) is high among older individuals, women, those with lower education, greater myopia severity, and longer axial length (AL), according to data from a consortium of Asian studies. Furthermore, myopic spherical equivalent (SE) is the strongest single predictor of MMD.

Researchers obtained individual-level data from 19,885 participants from four population-based studies, and 1,379 highly myopic individuals (AL >26.0 mm) from three clinic-based/school-based studies of the Asian Eye Epidemiology Consortium were pooled.

MMD was graded from fundus photographs and characterized by the presence of diffuse choroidal atrophy, patchy chorioretinal atrophy, and macular atrophy, with or without 'plus' lesion (lacquer crack, choroidal neovascularisation or Fuchs' spot).

The prevalence of MMD was 0.4 percent, 0.5 percent, 1.5 percent, and 5.2 percent among Asians in rural India, Beijing, Russia, and Singapore, respectively. In population-based studies, risk factors for MMD included older age (per year; odds ratio [OR], 1.13), female sex (OR, 2.0), SE (per negative dioptre; OR, 1.7), longer AL (per mm; OR, 3.1), and lower education (OR, 1.9; p<0.001 for all).

In clinic-based/school-based studies, MMD also showed similar associations with older age (OR, 1.07; p<0.001), female sex (OR, 2.1; p<0.001), longer AL (OR, 2.1; p<0.001), and lower education (OR, 1.7; p=0.005).

SE had the highest accuracy for predicting MMD (area under the curve [AUC], 0.92), followed by AL (AUC, 0.87). Accuracy marginally increased when SE was combined with age, education, and gender (AUC, 0.94).

The findings may guide risk profiling of patients in the clinic, especially those with severe myopia levels, the researchers said. This is important because detection of those with increased risk of MMD is crucial for appropriate monitoring, management, and timely visual rehabilitation.

Br J Ophthalmol 2020;doi:10.1136/bjophthalmol-2020-316648