Diabetes medication, metformin, is linked to less progression of age-related macular degeneration (AMD), the most common cause of blindness in Western countries. The corresponding study was published in BMJ Open.
“Most people who suffer from AMD have no treatment, so this is a great breakthrough in our search for new treatments. What we need to do now is test metformin as a treatment for AMD in a clinical trial. Metformin has the potential to save many people’s sight,” Dr. Nicholas Beare, Reader at the Institute of Life Course and Medical Sciences at the University of Liverpool, UK, said in a press release.
Epidemiological studies have found a link between metformin use and reduced AMD. In the current study, researchers analyzed eye photos from close to 2,500 participants over 50 years old who attended a routine diabetic eye disease screening programme in Liverpool, UK. In particular, they assessed for presence of AMD in photos, disease severity, and compared images of those taking metformin to those not taking the drug.
Ultimately, patients taking metformin were 37% less likely to develop the intermediate stage of AMD over five years than non-users. The results remained after adjusting for confounders. The researchers found that use of metformin was not linked to a significant reduction in late AMD. No association was found between metformin and early AMD.
Limitations to the findings include a lack of data on dose, duration of prior use, and compliance, as well as ‘relatively small numbers’ of patients who developed advanced AMD. The researchers also did not include data on diet, supplement use or smoking in their model. Lastly, they wrote that while their findings are applicable to people with diabetes, they are not necessarily generalizable to the general population.
“Our study supports undertaking a prospective clinical trial of metformin for reducing progression of AMD prior to the onset of advanced AMD,” wrote the researchers in their study.
Sources: EurekAlert, BMJ Open
