title: Effectiveness and safety of nutritional supplements in the treatment of hereditary retinal dystrophies: a systematic review.
abstract: The hereditary retinal dystrophies (HRDs) are a group of genetically determined disorders that result in loss of the visual function. There is a lack of standard pharmacological treatments or widely accepted nutritional recommendations. The objective of this review is to summarise the scientific evidence on the effectiveness and safety of nutritional supplements for the treatment of HRDs. We conducted a scientific literature search on Medline and PreMedline, EMBASE, SCI-EXPANDED, SSCI, and The Cochrane Library up to August 2014. Experimental, quasi-experimental and controlled observational studies were selected. Eight studies were ultimately included, seven on retinitis pigmentosa (RP) and one on Best disease. Vitamin A, vitamin E, docosahexaenoic acid (DHA), lutein and β-carotene were assessed. A 15 000 IU daily dose of vitamin A was reported to have shown a small protective effect on the progression of RP, as was the use of the carotenoids lutein and β-carotene. Different DHA doses has no effect on RP or Best disease. No supplement showed severe adverse effects in the selected studies although strong evidence of toxicity exists for high doses of vitamin A and β-carotene in certain populations. The selected studies concluded that there may be a small beneficial effect of vitamin A, lutein and β-carotene on the progression of RP. The limited evidence available indicates some well-designed additional studies on combined supplements strategies may achieve more robust conclusions. Moreover, the scarcity of evidence available on the treatment of HRD other than RP with nutritional supplements supports the need for further research efforts.
authors.affiliation: Fundación Canaria de Investigación Sanitaria (FUNCANIS), Islas Canarias, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Brito-García
authors.affiliation: Fundación Canaria para el Avance de la Biomedicina y la Biotecnología (BIOAVANCE), Universidad de La Laguna, Islas Canarias, Spain.|Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Madrid, Spain.
authors.forename: T
authors.initials: T
authors.lastname: Del Pino-Sedeño
authors.affiliation: Fundación Canaria de Investigación Sanitaria (FUNCANIS), Islas Canarias, Spain.|Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Madrid, Spain.|Centro de Investigaciones Biomédicas de Canarias (CIBICAN), Universidad de La Laguna, Islas Canarias, Spain.
authors.forename: M M
authors.initials: MM
authors.lastname: Trujillo-Martín
authors.affiliation: Institute of Applied Ophthalmo-Biology (IOBA), University of Valladolid, Valladolid, Spain.|RTIC patología ocular del envejecimiento, calidad visual y calidad de vida (OFTARED), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: R M
authors.initials: RM
authors.lastname: Coco
authors.affiliation: RTIC patología ocular del envejecimiento, calidad visual y calidad de vida (OFTARED), Instituto de Salud Carlos III, Madrid, Spain.|Unidad de Gestión Clínica de Oftalmología. Hospitales Universitarios Virgen Macarena y Virgen del Rocío, Sevilla, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Rodríguez de la Rúa
authors.affiliation: Centro de Investigaciones Biomédicas de Canarias (CIBICAN), Universidad de La Laguna, Islas Canarias, Spain.|Unidad de Apoyo a la Investigación. Gerencia de Atención Primaria, Servicio Madrileño de Salud, Madrid, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Del Cura-González
authors.affiliation: Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Madrid, Spain.|Centro de Investigaciones Biomédicas de Canarias (CIBICAN), Universidad de La Laguna, Islas Canarias, Spain.|Servicio de Evaluación de la Dirección del Servicio Canario de la Salud (SESCS), Tenerife, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Serrano-Aguilar
mesh_terms: D000975:Antioxidants / Q000627:therapeutic use*; D002338:Carotenoids / Q000627:therapeutic use; D019587:Dietary Supplements; D018450:Disease Progression; D004596:Electroretinography / Q000187:drug effects; D006801:Humans; D058499:Retinal Dystrophies / Q000628:therapy*; D014792:Visual Acuity / Q000187:drug effects; D014796:Visual Perception / Q000187:drug effects; D014815:Vitamins / Q000627:therapeutic use*
chemical_list: D000975:Antioxidants; D014815:Vitamins; D002338:Carotenoids