Demographic factors affecting the risk for myopic macular degeneration (MMD) have, until now, not been thoroughly explored, although prior research demonstrates objective elements such as higher minus refractive error, older age, and longer axial length (AL) increase the odds. And although no link is thought to exist between MMD and education level, data representing 21,264 participants, pooled from 7 studies indicates otherwise.
A significant association between low education and MMD in 4 population-based investigations (P <.001) and 3 high myopia studies (P <.005), was reported by a combined analysis of the Asian Eye Epidemiology Consortium, published in the British Journal of Ophthalmology. Another demographic aspect, female sex, was also significantly related to MMD in the analyses (both P <.001).
In group 1, population-based studies included 19,885 individuals from Singapore, China, and India. Russian residents of Asian ancestry were also included. Group 2 comprised high myopia studies with 1379 participants with myopia for whom AL was more than 26.0 mm in 1 or both eyes —recruited at hospitals, clinics, and schools in South Korea and China. All investigations graded MMD with the 2015 International Photographic Classification and Grading System for Myopic Maculopathy of the meta-analysis for pathologic myopia study group (META-PM). MMD was defined as META-PM category 2 to 4, or any “plus” lesion.
Group 1’s multivariable adjustment analysis showed higher myopic spherical equivalent, older age, and longer AL were associated with MMD (all P <.001), and group 2’s data also showed older age and longer AL were risk factors (both P <.001). The most significant element in population-based studies, though, was spherical equivalent (SE). Even when combining variables of SE and age, or SE and sex, risk expressed as area under the curve (AUC) did not greatly increase (P >.05), and “Myopic refractive error alone had one of the highest predictive ability of MMD risk (AUC of 0.92).”
After adjustment, hypertension and diabetes showed no significant association with MMD in group 1 or group 2 data.
Connections found between low education and MMD may signify low socioeconomic status and thus, nutrient disadvantages, investigators suggested. Also, higher incidence of MMD in women may occur due to their likelihood to have less education (49.6%) than men (38.0%). Researchers also speculate the low education–MMD link may indicate MMD is not correlated with extensive time spent in near focus.
Selection bias in samples from single hospitals or schools represent a limitation, as well as cross-sectional design, differences in methodologies among the consortium, and unavailable data for ocular comorbidities. Conversely, the pooled sample was large and diverse, and a single standardized classification system for grading MMD was used. This report concurred with previous studies which demonstrated SE, AL, and age all impact MMD.
Notably, investigators found one-third of eyes with severe MMD exhibited low or moderate myopia, suggesting the disorder may occur in those who do not meet the typical high myopia mark of -5.0 D. “This also suggests that screening for MMD only in people with high myopia may not be the most appropriate strategy,” according to the report.
Disclosures: One study author declared affiliations with the biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Wong YL, Zhu X, Tham YC, et al. Prevalence and predictors of myopic macular degeneration among Asian adults: pooled analysis from the Asian Eye Epidemiology Consortium. Br J Ophthalmol. 2021;105:1140–1148. doi:10.1136/bjophthalmol-2020-316648