Visual acuity changes and conversion to neovascular AMD determined over 3 years in large patient cohort.
Reviewed by Thomas A. Ciulla, MD
A deep dive into the effects of geographic atrophy (GA) found that the end stage of age-related macular degeneration is associated with a “meaningful disease burden,” according to Thomas A. Ciulla, MD, from the Department of Ophthalmology, Indiana University School of Medicine, Indianapolis.
This retrospective study showed that at 3 years, patients lost 2 lines of vision and those with modestly impaired vision at baseline were at the greatest risk of further vision loss.
Ciulla and colleagues conducted a database search of the electronic medical records (EMR) of over 800,000 patients from US retina practices. The eligible patients had been diagnosed with nonexudative AMD with advanced atrophy (with/without subfoveal involvement). The patients had not been diagnosed with neovascular AMD before the date on which the GA was diagnosed in at least 1 eye. Patients had a minimal follow-up of 3 years.
A total of 23,730 eyes were identified with GA; of these, 4,972 were excluded because of a concurrent diagnosis of neovascular AMD. The patients were a mean age of 79 years and 66% were women. Over a third of eyes (35%) were from patients who had neovascular AMD in the fellow eye, Ciulla recounted.
“Eyes with GA are at meaningful risk of conversion to neovascular AMD,” Ciulla reported. The data analysis showed that 25% converted to neovascular AMD with a mean time to conversion of 25 months. During the first year, 8.4% converted, during the second year 5.9%, and during the third year 4.6%.
Eyes with GA lost 2 lines of visual acuity by year 3. When broken down by years, the losses were 3, 6, and 10 letters, respectively, during years 1, 2, and 3.
“Eyes with GA and modest visual impairment at baseline may be at the greatest risk of further central vision loss. The patients with a baseline visual acuity of 20/40 to 20/100 lost 3 lines of vision by year 3, likely as the result of progression of juxtafoveal GA to subfoveal GA,” Dr. Ciulla commented.
The study also showed, in the subset of patients with central subfield thickness (CST) recorded in the EMR, the CST declined minimally over time in GA, with a loss of 3, 5, and 8 microns by years 1, 2 and 3 years, respectively.
While the study had certain limitations, ie, its retrospective nature, no strict eligibility criteria, loss of patients to follow-up over time, and non-standardized visual acuity assessment, Ciulla pointed out, there were 3 important findings:
Thomas A. Ciulla, MD
He is from the Department of Ophthalmology, Indiana University School of Medicine, Indianapolis and has no financial interest in this subject matter.