A major, two-year European Research Council-funded programme involving over 100 people diagnosed with the early stages of the most common cause of blindness has shown an improvement in the vision of those taking a dietary supplement of carotenoids.
Participants in the study all had the early stages of age-related macular degeneration (AMD) which is estimated to impact on 7.2% of Irish adults aged 50 and over.
Those living with AMD would usually have been expected to experience a continued deterioration in their vision over the two years of the clinical trial. Instead, those receiving carotenoids showed a significant improvement across 24 out of 32 tests of vision. 40% of trial participants had what is deemed to be a clinically meaningful improvement in their vision after 24 months.
The research was conducted by a team from the Nutrition Research Centre Ireland (NRCI) at Waterford Institute of Technology (WIT). During the trial, the volunteers taking part received supplementary meso-zeaxanthin, zeaxanthin and lutein, the three carotenoids that make up macular pigment. Improvements in vision were particularly marked among those receiving all three carotenoids compared to those receiving only zeaxanthin and lutein. Carotenoids are naturally-occurring pigments that give many fruit and vegetables their colour.
Results from the study – the first of its kind in the world – are published in Investigative Ophthalmology & Visual Science (IOVS), the most respected, peer-reviewed journal in eye science.
The trial – called CREST (Central Retinal Enrichment Supplementation Trial) AMD – was conducted by Kwadwo Owusu Akuffo; Stephen Beatty; Jim Stack; David Kelly; Laura Corcoran and John Nolan from NRCI along with Tunde Peto, Queen’s University Belfast; Jim Stringham, University of Georgia, USA and Irene Leung, University College London Institute of Ophthalmology.
Prof John Nolan who co-founded the NRCI and the original Macular Pigment Research Group in Waterford and who is now Howard Chair of Human Nutrition at WIT, said: “These are hugely exciting findings and build on previous work that has been done at our Centre and elsewhere. AMD and the impaired vision that comes with are a huge burden for patients and their families. The disease also brings a considerable economic burden, especially in its later stages. So, there’s a huge prize in finding an early intervention that can avert the need for expensive therapies and supports.
“These findings are the culmination of a tremendous body of work by a diverse group of committed people going back over several years while we also owe a huge debt of gratitude to the volunteers who participated in the trials without any guarantee of a favourable outcome. It’s been both humbling and rewarding to work with these people and to see the difference in their quality-of-life as the decline in their vision is arrested and they begin to notice a distinct improvement.
“The team involved also appreciate the support we have consistently received from Waterford Institute of Technology and a range of funding agencies including the European Research Council (ERC) who first funded our work in 2011.”