People with stargardt disease can experience slow degeneration and progressive vision loss, but it is rare for them to go completely blind. Visual loss can progress at different rates and in different degrees from person to person and even from family to family. A study in 2018 showed that although many patients with Stargardt disease lose visual acuity to the 20/200 to 20/400 range, and some lose visual acuity beyond 20/400, none of these patients reached either light perception or no light perception.