How Diabetes Can Impact Eye Health

In 2021, researchers estimated about 11.6% of the U.S. population had diabetes, according to the Centers for Disease Control and Prevention (CDC).

This chronic metabolic disease, which happens when the body’s glucose, or blood sugar, is too high, can affect organs across the body, including the eyes. Niranjan Manoharan, MD, assistant professor of ophthalmology at the University of Colorado School of Medicine, often treats patients who experiences these vision changes or ocular problems that manifest along with diabetes.

Sometimes he can be the first to spot diabetes, which doctors often say is a “silent” disease, in a patient.

“I've noticed this many times. Patients don't know they have diabetes until we find a problem in the eyes, but they don’t suspect they have diabetes because they haven't had routine care with their primary care doctor,” he says.

Manoharan explains some of the ways diabetes affects ocular health and why managing blood sugar and keeping up with primary care is crucial for vision and keeping the eyes healthy.

Can you explain why diabetes and eye health are connected?

Diabetes affects many organs in the body in a similar way. It essentially slowly damages the tiny blood vessels in the body, including the eyes. When those blood vessels are damaged, we can see a whole slew of problems, such as retinal damage to lack of perfusion, bleeding and swelling in the retina, retinal detachment, glaucoma and cataracts.

What are some symptoms patients in later stages of the disease experience?

In more serious cases and late term complications, the patient can experience retinal detachment or bleeding in the eye. This can be harmful to a person’s vision and cause irreversible blindness.

Are these diabetes-related conditions treatable and what does that treatment look like?

It’s critical to catch this disease early so we can work with primary care doctors and endocrinologists to get it under control before it leads to the damage we’ve talked about. If left untreated, a person could experience permanent vision loss.

There is a point in diabetes where there is early damage in the eye but the patient might not necessarily know it because they’ve been able to manage with their vision, but as ophthalmologists we can see the damage in the blood vessels. In these early stages, we can reverse that damage, but there becomes a point where we cannot.

In advanced stages, treatment is often a combination of surgery, laser, or injections in the eye. We see a lot of variability in the disease, so it really depends on the individual patient.

Patient education is crucial in diabetes and eye conditions that can follow. What should people know about screenings and preventative care?

Even if you feel like you're healthy and doing well, hypertension and diabetes are silent diseases. You don't know until there's end organ damage. That's when you start to feel it. By then, a lot of damage could already be done, and it's going to be harder to control.

A quick annual checkup with a primary care provider to check your blood pressure and glucose can go a long way, because if we can catch these early, subtle changes, it’s much easier to treat and manage.