Late-onset Stargardt disease represents a subtype of Stargardt disease that occurs most commonly with one severe and one mild ABCA4 variant, according to findings published in Ophthalmology. Rob WJ Collin, PhD, and colleagues conducted a retrospective cohort study of 71 patients to examine the characteristics, underlying genetics, and progression of late-onset Stargardt disease. The median age of disease onset was 55 (range, 45-82). The most common genotype was a combination of a mild and severe variant in ABCA4 (n=49; 69.0%), and the most common allele, c.5603A>T (p.Asn1868Ile), was identified in 43 patients (60.6%). The researchers observed no combinations of two severe variants and all patients had flecks on fundus auto fluorescence imaging at initial presentation. Extrafoveal atrophy was reported in 38.9% of eyes. Time-to-event curves indicated a median duration of 15.4 years from onset to foveal involvement, and the median visual acuity decline was -0.03 Snellen decimals per year.
