Researchers Develop a Promising New Test for Early Diagnosis of ‘Alzheimer’s of the Eye’

What would you think if words started disappearing suddenly from the books and news articles you were reading? Or you started noticing dark spots on the screen while watching a show on Netflix? Or you suddenly had difficulty recognizing faces?

While you might start thinking that your mind is playing tricks on you, in the case of age-related macular degeneration (AMD), these disorienting experiences are caused by structural damage to the eyes.

Clinicians and researchers have struggled to find a predictive measure that identifies patients at risk for developing the advanced stages of the disease.

Researchers based at Massachusetts General Hospital and Massachusetts Eye and Ear Infirmary may have identified a solution. The research team has successfully tested a new method for identifying patients with AMD by looking at specific markers in their blood.

The blood-based test has the potential to improve early diagnoses for AMD patients and may lead to more treatment options, as well as personalized, precise treatment for earlier stages of the disease.

What is Age-Related Macular Degeneration?

Known as the ‘Alzheimer’s of the eye,’ AMD affects nearly five million people across the world, and is the leading cause of blindness in people over 50 in developed nations.

The disease is caused by a buildup of yellowish lipid proteins underneath the retina, the light sensitive portion of the eye. Over time, the proteins damage the structure of the retina, which leads to the symptoms described above. By the time patients start to experience the visual degradation that accompanies AMD, the damage is already done.

Finding a Method for Diagnosis

To test out their new method for diagnosing AMD, scientists took blood samples from 90 participants with varying degrees of AMD, including early, intermediate and late-stage cases. These samples were then compared to 30 individuals who do not have AMD.

Researchers used a new technique known as “metabolomics,” — the study of tiny particles called metabolites in the body that reflect our genes and environment.

Their analysis revealed 87 metabolites that were significantly different between subjects with AMD and those without. The team also noted varying characteristics between the blood profiles of each stage of disease.

Out of the 87 molecules identified, the majority were found to be lipids, which have long been a point of interest in AMD research.

“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 [lipid] 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, M.D., Chief of Ophthalmology at Massachusetts General Hospital and Mass Eye and Ear.

Preventative Measures

More research needs to be done before the blood tests are available in the clinic. For now, the best way to monitor patients for signs of AMD is by conducting regular eye tests after the age of 45.

Given that risk factors for AMD include being overweight, having high blood pressure and smoking or drinking alcohol to excess, it may be possible to reduce your risk by making healthy lifestyle choices, including:

  • Maintaining a healthy weight
  • Eating lots of green leafy vegetables and fish
  • Quitting smoking
  • Managing your blood pressure

Find more information on AMD on the National Eye Institute website.

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Researchers Recommend New Eye Exam Screening for Patients with Type 1 Diabetes: Five Things to Know

12538332 - looking through the glasses at eye chartTreatment guidelines for patients with type 1 diabetes have long called for yearly eye exams. But is there an alternative to this one-size-fits-all approach that could reduce patient burden and costs while providing a quicker diagnosis? Findings from a recent study, published in the New England Journal of Medicine, lend insight into a possible new eye screening protocol. Here are five things to know:

  1. Diabetic retinopathy is the leading cause of blindness among adults. It occurs when chronically high blood sugar from diabetes damages the light-sensitive tissue in the back of the eye. Fortunately, screening can catch this disease before irreparable damage is done, and there are several therapies available to treat the condition. Guidelines currently recommend routine yearly eye exams within three to five years of a type 1 diabetes diagnosis, but these recommendations were based on now-outdated research.
  1. To reevaluate the current recommendations, David Nathan, MD, Director of the Diabetes Center and Clinical Research Center at Massachusetts General Hospital, and a team of researchers analyzed approximately 24,000 retinal exams obtained over 30 years from about 1,400 participants with type 1 diabetes.
  1. Based on their analysis, researchers developed new recommendations that suggest patients with type 1 diabetes should get eye exams to detect diabetic retinopathy based on the presence and severity of diabetic retinopathy, rather than on the automatic, annual schedule that is currently recommended. For patients with type 1 diabetes and a current average blood glucose level of 6 percent (within the American Diabetes Association’s recommended target range), researchers recommend the following eye exam schedule:
  • With no retinopathy, every four years.
  • With mild retinopathy, every three years.
  • With moderate retinopathy, every six months.
  • With severe retinopathy, every three months.
    Researchers suggest patients with higher current average blood glucose levels (for example, 8-10 percent as opposed to 6 percent) have eye exams more often, as they are at higher risk to develop the disease. The new recommendations also call for taking photographs of the back of the eye rather than physical examination with an ophthalmoscope, which is thought to be less accurate.
  1. Overall, researchers say the new, individualized schedule would result in earlier detection of the advanced retinopathy that requires treatment to save vision compared with annual exams, while at the same time reducing the frequency of eye exams by half. That would translate into an overall savings of $1 billion.
  1. Researchers are still questioning whether physicians would adhere to these new recommendations, if implemented. “The risk is that physicians may find it easier to schedule an annual eye examination compared with the new individualized schedule, which may be more difficult for physicians and patients to remember,” says Nathan. The next step is to discuss how to potentially incorporate the guidelines into patient care. They also plan to conduct further studies to investigate if this screening strategy could be applied to patients with type 2 diabetes.

Patients with High-Risk Macular Degeneration Show Improvement with High-Dose Statin Treatment

Although effective treatments are available for the wet form of AMD, they are currently lacking for the more prevalent dry form. The researchers found evidence that treatment with high-dose atorvastatin (80mg) is associated with regression of lipid deposits and improvement in visual acuity, without progression to advanced disease, in high-risk
AMD patients. Their findings were published in EBioMedicine — a new online journal led by editors of the journals Cell and The Lancet — and not only further the connection between lipids, AMD and atherosclerosis, but also present a potential therapy for some patients with dry AMD.