[Metabolic therapy for early treatment of age-related macular degeneration].
Review
Overview
abstract
Currently, age-related macular degeneration is one of the most common eye diseases causing severe and permanent loss of vision. This disease is estimated to affect approximately 300-500 thousand Hungarians. While earlier no treatment was available, in the recent decade an antioxidant therapy became very popular using combinations of high dosage antioxidant vitamins C, E, beta carotene and zinc. Based on theoretical concepts and mostly in vitro experiences, this combination was thought to be effective through neutralizing reactive oxygen species. According to a large clinical trial (AREDS) it reduced progression of intermediate state disease to advanced state, but did not influence early disease. This original combination, due to potential severe side effects, is not on the market anymore. However, the efficacy of modified formulas has not been proved yet. Recently, the metabolic therapy, a combination of omega-3 fatty acids, coenzyme Q10 and acetyl-L-carnitine has been introduced for treating early age-related macular degeneration through improving mitochondrial dysfunction, specifically improving lipid metabolism and ATP production in the retinal pigment epithelium, improving photoreceptor turnover and reducing generation of reactive oxygen species. According to a pilot study and a randomized, placebo-controlled, double blind clinical trial, both central visual field and visual acuity slightly improved after 3-6 months of treatment and they remained unchanged by the end of the study. The difference was statistically significant as compared to the base line or to controls. These functional changes were accompanied by an improvement in fundus alterations: drusen covered area decreased significantly as compared to the base line or to control. Characteristically, all these changes were more marked in less affected eyes. A prospective case study on long-term treatment confirmed these observations. With an exception that after slight improvement, visual functions remained stable, drusen regression continued for years. Sometimes significant regression of drusen was found even in intermediate and advanced cases. All these findings strongly suggested that the metabolic therapy may be the first choice for treating age-related macular degeneration. Currently, this is the only combination of ingredients corresponding to the recommended daily allowance, and at the same time, which showed clinically proved efficacy.