Epidemiology of pathologic myopia in UK adults with high myopia

AimsTo conduct the first cross-sectional epidemiological investigation of pathologic myopia (PM) in UK adults with high myopia. MethodsFundus photographs of 3,024 highly myopic eyes (spherical equivalent refraction, SER [&le;] -5.00D) from 2,000 randomly sampled adults (aged 40-70 years) in the UK Biobank were double graded by an ophthalmic reading centre using the Meta-analysis for Pathologic Myopia framework. Adjudication was performed by one of two retinal specialists. Multivariable mixed-effects logistic regression was used to explore potential risk factors and fundus biomarkers--initially controlling for SER, age and sex, before including all variables with p<0.10 in a single model. ResultsPM was present in 1,138 of 3,006 gradable fundus photographs, with 41.7% (95% CI: 39.5%-43.9%) of participants affected in at least one eye graded. Most eyes with PM exhibited diffuse chorioretinal atrophy (97.4%), while the more severe stages-- patchy chorioretinal atrophy and macular atrophy--were observed in only 24 and 5 eyes, respectively. Thirteen eyes had "plus" lesions or suspected staphyloma. Factors independently associated with increased odds of PM (all p<0.05) included decreasing SER (adjusted odds ratio: 0.22, 95% CI: 0.15-0.32), older age (2.20, 1.63-2.97), female sex (1.87, 1.12-3.12), lower deprivation (0.73, 0.56-0.94), White ethnicity (52.3, 17.3-158.3), lower retinal arteriovenous ratio (0.47, 0.37-0.58), increased retinal vascular complexity (4.68, 3.22-6.81) and a relatively horizontal disc orientation (2.98, 1.88-4.72). None of the explored modifiable lifestyle or health-related variables were associated with PM. ConclusionsPM prevalence is high among mid-life adults with high myopia in the UK Biobank. Although most cases are mild, the progressive and age-related nature of PM means an elevated risk of irreversible visual impairment for these individuals in later life.