An analysis of Denmark's FORSYN study suggests new advances in the treatment of chorioretinal vascular diseases have significantly reduced vision loss.
A new study examining visual acuity and causes of central visual loss in Denmark suggests recent advances in the therapy of chorioretinal vascular diseases may play an important role in reducing vision loss.
Results from the FORSYN study link the introduction of anti-vascular endothelial growth factor (VEGF) therapies to a significant decrease in central visual loss secondary to exudative age-related macular degeneration (AMD) and diabetic retinopathy.1
“Although the screen activities conducted in the studied population may not necessarily be representative for the entire country, the trend underlines the benefits of regulating modifiable risk factors, participants in screening programs, and efficient treatment including photocoagulation and anti-VEGF treatment,” investigators wrote.1
The purpose of the FORSYN project was to study visual health in the Danish population from 2020 to 2022 after the implementation of the recent treatment advances. Led by Dr. Toke Bek, Department of Ophthalmology, Aarhus University Hospital, the current analysis reported the results of best-corrected visual acuity (BCVA) and causes of central visual loss within the examinations.
Within the population-representative sample of 10,350 citizens living within 40 kilometers of the university hospital, patients were invited to answer the Visual Function Questionnaire (VQF-25) about quality-of-life related to vision, measurement of visual acuity, and a non-mydriatic examination of the eyes. Investigators noted the data were corrected for selection bias by demographic and socioeconomic factors to better represent the adult Danish population.
According to the findings, the population-adjusted BCVA in Early Treatment for Diabetic Retinopathy Study (ETDRS) letters (mean ± SD) were significantly different in the worse eye (84.1 ± 0.25), the better eye (88.4 ± 0.11) and binocularly (89.2 ± 0.15). Visual acuity was noted as significantly better in men (mean, 89.7 ETDRS letters; n = 1520) than in women (mean, 88.9 ETDRS letters; n = 1864), and the significance was unaffected by age as a covariate.
The population-adjusted frequencies and causes of BCVA less than 75 ETDRS letters in the better eyes revealed the most frequent causes of central vision loss were atrophic AMD, chorioretinal diseases other than diabetic retinopathy and AMD, and neuroophthalmic disease.
Further analysis indicated only 0.22% (95% confidence interval [CI], 0.14% – 0.33%) of the population had a BCVA in the better eye at or below 35 ETDRS letters, corresponding to social blindness. Exudative AMD or diabetic retinopathy was not the cause of vision loss in any of these patients.
While the prevalence of central visual loss secondary to atrophic AMD was comparable to the estimated global prevalence, eyes with exudative AMD comprised an insignificant population of eyes with central visual loss, according to the data. As a result, investigators noted the data confirm successful implementation of anti-VEGF treatment for exudative AMD.
Bek and colleagues additionally noted the increased occurrence of age-related diseases including atrophic AMD and cataract was parallel to older age.
“These diseases are linked to age, and it can therefore be expected that the demand for vision-saving treatments will increase in parallel with the increase in the aging population,” investigators wrote. “This will be a significant challenge for the healthcare system in the coming years.”1
1. Bek, T. & Bech, B.H. (2023) Visual acuity and causes of central visual loss in the adult Danish population 2020–2022. Results from the FORSYN study. Acta Ophthalmologica, 00, 1–10.