ARVO 2023: Capillary density as a biomarker for the assessment of cognitive impairment in Alzheimer's Disease

Amir H. Kashani, MD, PhD, sat down with David Hutton, Managing Editor, Ophthalmology Times®, to discuss his presentation at this year's ARVO meeting on optical coherence tomography and the assessment of cognitive impairment in Alzheimer's Disease and other related dementias.

Video transcript

Editor’s note: This transcript has been edited for clarity.

David Hutton:

I'm David Hutton of Ophthalmology Times. The Association for Research in Vision and Ophthalmology is holding its annual conference this year in New Orleans. I'm joined today by Dr. Amir Kashani, who presented "Optical Coherence Tomography Angiography Based Capillary Density as a Biomarker for the Assessment of Cognitive Impairment, in Alzheimer's Disease and Related Dementias." Dr. Kashani, thank you so much for joining us today. Tell us about your presentation.

Amir H. Kashani, MD, PhD:

Hi, David, thank you so much for having me, it's really great to be able to share some of this work with the public and ophthalmologists at large. So we're presenting some really exciting work at ARVO this year, describing the association between capillary changes in the retina and vascular events that may be occurring within the brain. And specifically vascular events that might be causing cognitive impairment, and dementia. Most people think of dementia as Alzheimer's, but there's actually a whole category of dementia that's caused by vascular disease. Which we commonly think of as a stroke. But people don't necessarily need to have a stroke, to have this kind of vascular cognitive impairment. Subtle changes in capillaries in the brain are thought to cause problems with cognition. The problem is that scientists can't - and the clinicians, neurologists - can't look inside the brain to see capillaries. And we have the advantage in the eye of being able to look directly through the transparent media of the eye, and visualize the capillaries in the back of the eye. And because the eye and the brain are both part of the central nervous system, there's evidence in our hypothesis that capillary changes in the retina will reflect capillary changes in the brain. So what we're presenting at ARVO this year is some of the findings and research where we've looked at the capillaries of subjects, in the retinas of subjects who are at risk for vascular cognitive impairment, and associated those capillary measurements with various aspects of cognitive function. And what we're able to show is that actually, as capillary density in the retina decreases, certain aspects of cognitive function also decrease. And those are aspects of cognitive function that people commonly call executive functioning types of tasks. So higher order, higher level functioning, that is also by the way associated with stroke related cognitive impairment.

David Hutton:

Ultimately, what can this mean for ophthalmologists and the patients they treat?

Amir H. Kashani, MD, PhD:

So ultimately, I think it starts to shed light on the fact that what we see in the eye is often a reflection of what's going on in other places in the body, and specifically in the brain. We think that in the long run, as we kind of delve further into these associations, that we may be able to use the vascular changes in the retina as a biomarker for risk of cognitive decline over a long period of time. As I mentioned, neurologists can't look inside the brain at capillaries. But perhaps if we can detect capillary level changes in the retina, and people who are at risk for developing cognitive impairment, we might be able to screen them better, counsel them better, start earlier treatments and even think about treating them earlier.