Eye Vessel Blockages Signal Higher Dementia Risk
How retinal blood flow problems may offer an early clue to Alzheimer’s disease
People diagnosed with blocked blood vessels in the retina were significantly more likely to later develop Alzheimer’s disease, vascular dementia, or any form of dementia. Because the retina shares blood vessel and nerve features with the brain, eye findings may serve as an early warning sign of broader neurovascular disease.
Study Details
Alzheimer’s disease develops gradually over many years, often before memory symptoms become obvious. Researchers have increasingly focused on the role of blood vessel health in the brain. The retina offers a rare opportunity to directly observe small blood vessels without invasive tests.
In this nationwide cohort study from Taiwan, investigators examined whether retinal vascular occlusion, a condition caused by blocked arteries or veins in the eye, was associated with a higher long-term risk of dementia.
Methodology
Researchers analyzed insurance claims data covering nearly the entire Taiwanese population. They compared outcomes in patients newly diagnosed with retinal vascular occlusion to a much larger group of age- and sex-matched individuals without the eye condition.
Key features of the study included:
Over 39,000 patients with retinal vascular occlusion
Nearly 400,000 matched controls
Average follow-up of just over four years
Dementia diagnoses confirmed through repeated outpatient visits or hospital discharge records
This approach allowed researchers to track real-world dementia risk over time rather than relying on short-term screening tests.
Key Findings
Patients with retinal vascular occlusion were about 1.6 times more likely to be diagnosed with Alzheimer’s disease.
Risk of vascular dementia was nearly 1.8 times higher compared with individuals without retinal vessel blockages.
Both retinal artery occlusion and retinal vein occlusion showed similar increases in dementia risk.
The association was strongest in adults over age 65.
Surprisingly, the link appeared more pronounced in people without traditional vascular risk factors such as diabetes or hypertension.
Implications for Practice
For patients, a diagnosis of retinal vascular occlusion may signal more than a vision problem. It could reflect underlying blood vessel changes that also affect the brain. Earlier cognitive monitoring after an eye vascular event may help identify dementia symptoms sooner, when supportive interventions are most effective.
For healthcare providers, these findings reinforce the concept of the eye as a window into brain health. Collaboration between ophthalmology, primary care, and neurology may be especially valuable after retinal vascular events, even in patients who appear otherwise healthy.
While this study does not prove that eye vessel blockages cause dementia, it strongly suggests they may serve as an early marker of shared vascular disease affecting both the eye and the brain.