Potential Biomarkers of Age-Related Macular Degeneration Discovered

Lipid biomarkers in human blood can serve as indicators for age-related macular degeneration (AMD), leading to earlier diagnoses and more precise treatment, according to a recent study.

AMD is the leading cause of blindness in individuals over 50 years. It affects more than 1.75 million individuals in the United States, and experts expect the prevalence to rise to 3 million by 2020 due to the rapid aging of the population.

There are several genetic and lifestyle risk factors of AMD, but reliable measures to identify at-risk patients are lacking. This includes patients who may progress to the advanced form of the disease.

In a study published in Ophthalmology, investigators used a novel technique called metabolomics to identify blood profiles associated with AMD and its severity through laboratory testing.

“The study utilized a technique known as metabolomics, or the study of the tiny particles called metabolites, in our body that reflect our genes and environment,” said first author Ines Lains, MD. “The metabolome—–the set of metabolites present in an individual––is thought to closely represent the true functional state of complex diseases.

“This is why we used it to test 90 blood samples obtained from study participants with all stages of AMD (30 with early-stage disease, 30 with intermediate-stage, and 30 with late-stage) and 30 samples from patients without AMD.”

Using this approach, the investigators found 87 metabolites in the blood that were significantly different between subjects with AMD and those without AMD. Furthermore, there were varying characteristics between the blood profiles of each stage of disease.

“Because the signs and symptoms of early stage AMD are very subtle, with visual symptoms only becoming apparent at more advanced stages of the disease, identification of biomarkers in human blood plasma may allow us to better understand the early to intermediate stages of AMD so we may intervene sooner, and ultimately provide better care,” said co-senior author Joan W. Miller, MD.

Most of the 87 molecules identified through metabolomics resided in the lipid pathway, with 6 of 7 most significant metabolites identified being lipids. Prior studies have suggested lipids may play a role in the development of AMD, and the findings from the current study supports this.

These findings may lead to improvement in earlier diagnoses of patients with AMD, as well as more personalized treatment options for earlier stages of the disease, according to the authors.

“We believe this work will help launch the era of personalized medicine in treatment of AMD,” said co-senior author Deeba Husain, MD. “Our work gives us a novel biomarker for early diagnosis, and gives us clues to differentiate the progressors from non-progressors. This research also gives us insight into important role of lipids in AMD, which will provide novel targets for treatment in the early stage of disease, thus preserving vision in AMD.”