Currently, methods for detecting cognitive disorders, such as MRI and PET scans, are time-consuming, not widely available, and expensive. Routine eye exams, such as OCT and OCT angiography, can be easily performed within minutes without patient discomfort and are widely available in U.S. ophthalmic clinics. People with diabetes are more likely to develop Alzheimer’s disease and other cognitive disabilities as they age. Routine eye imaging can now detect changes in the retina that could be associated with cognitive problems in older people with type 1 diabetes, according to researchers at the Joslin Diabetes Center. These findings could lead to a relatively simple approach for early detection of cognitive impairment in this population, allowing for improved understanding, diagnosis, and treatment. 

If you can detect the condition at an earlier stage, when they’re still asymptomatic, that may benefit patients,” Ward Fickweiler, MD, a Joslin postdoctoral fellow and first author on the paper said. Earlier detection also could aid the quest to develop better therapies for neurocognitive diseases.

The Study

The scientists drew on eye scans routinely gathered from patients as part of normal vision care at Joslin’s Beetham Eye Institute. One set of scans was based on optical coherence tomography (OCT, a technique employing light to provide cross-sections of the retina). The second set of scans employed OCT angiography (OCTA, an extension of OCT technology that examines blood vessels in the retina). Both types of scans are non-invasive and widely available in eye clinics in the United States and can be performed within minutes. The study enlisted 129 participants in the Joslin Medalist Study, which examines outcomes among people who have had type 1 diabetes for 50 years or longer. These volunteers took a series of cognitive tests that included tasks probing memory function as well as psychomotor speed (assessing the time it took to arrange objects by hand).

Although larger clinical trials are required to validate these findings, Routine eye imaging tends to identify the cognitive changes that occur in people with diabetes, according to Fickweiler. In addition to type 1 diabetes follow-up, King and his colleagues plan to conduct a similar analysis for type 2 diabetes patients. PDR is also linked to a cognitive loss in this much broader group of patients, who are also subjected to OCT and OCTA eye scans as part of their routine vision treatment.