Diabetes and Your Eyes

by | Nov 14, 2019

November is Diabetic Eye Disease Awareness Month, an ideal time to take a deeper dive into the disease we hear so much about. As eye care professionals, one of our areas of concern is that uncontrolled diabetes can affect your vision, and is a leading cause of blindness for individuals under the age of 74.

What is Diabetes?

Diabetes is a metabolic disorder characterized by high levels of sugar, or glucose, in your blood. Having low levels of glucose in your bloodstream is normal, as sugar is the nutrient that provides energy to your body on a cellular level. Your pancreas produces insulin, a hormone that enables cells to convert the glucose in your bloodstream into energy.

However, if your pancreas isn’t making enough insulin or your cells resist the effect of insulin—or if both conditions are present— you’re at high risk for diabetes. Without enough insulin working in your body, you’ll end up with an excess of glucose in your bloodstream, a condition that can cause serious problems.

Diabetes is a chronic, progressive disease. There is no cure, but it can be treated with careful monitoring of your diet, regular testing of blood glucose levels, and medications.

What are the Two Types of Diabetes? There are two different kinds of diabetes:

  • Type 1 Diabetes

Sometimes called juvenile-onset or insulin-dependent diabetes, Type 1 diabetes is typically diagnosed before age 30 and impacts 5-10% of diabetics. The primary cause of Type 1 diabetes is low or no insulin production. It’s not clear why some people don’t produce adequate amounts of insulin—it could be genetic or an autoimmune defect. Type 1 diabetics require regular insulin injections throughout their lifetimes.

  • Type 2 Diabetes

Known as adult-onset, or non-insulin dependent diabetes, Type 2 diabetes is diagnosed after age 30, typically, and is the more prevalent form of the disease. Between 90-95% of all diabetics are Type 2 diabetics. The cause of this type of diabetes is that the pancreas doesn’t produce enough insulin, or the cells in your body can’t use it efficiently—or both. This results in glucose levels rising uncontrollably in the bloodstream.

What is Pre-Diabetes?

If you’re among the 86 million Americans classified as pre-diabetic, your blood sugar levels are higher than usual but aren’t quite high enough to be diagnosed with diabetes. If you fall into this category, it’s important to take significant steps to prevent the condition from progressing into diabetes. These steps include increasing exercise and activity, losing weight, and altering your diet to focus on foods with a low glycemic index.

Obesity and living a sedentary lifestyle are primary risk factors for diabetes, so lowering body weight and increasing activity level are smart strategies for decreasing your risk.

Some symptoms of diabetes include being overly thirsty, urinating frequently, increased appetite and unexplained weight loss. Having a blood glucose level over 200mg/dL is the diagnostic level for diabetes.

How Does Diabetes Impact the Body?

Too much blood sugar in the bloodstream creates a problem for your body’s blood vessels, causing damage and complications. Diabetes can cause severe damage to your eyes, nerves, kidneys and almost every system in the body. Diabetes also impacts the cardiovascular system, doubling your risk of having a heart attack or stroke.

How Does Diabetes Affect Your Eyes?

Uncontrolled high blood sugar from diabetes can cause vision loss and blindness – either temporarily or permanently.

Temporary blurriness is often experienced when a diabetic patient is changing medications. Having high blood sugar changes the fluid levels in the tissues of your eyes, causing swelling. This can hinder your eyes’ ability to focus, causing blurry vision. When glucose levels are back under control, such temporary blurred vision often goes away.

However, if your body remains in a state of high blood sugar levels consistently, it causes damage to the tiny capillaries and other blood vessels that feed the tissues in the back of the eyes.

Damage to your eyes can begin during pre-diabetes, where your blood sugar is higher than it should be but not yet high enough for a full diabetes diagnosis.

When your optometrist examines the back of your eyes during a dilated eye exam, he or she can see whether your eyes’ blood vessels are functioning normally or have been leaking fluid into the back of the eye and causing swelling. This swelling can lead to high pressure inside the eye, which is dangerous and can cause vision loss.

How do Optometrists Detect Undiagnosed Diabetes?

Optometrists are often the first line of defense in diagnosing pre-diabetes and diabetes, as the sensitive tissues in the eye can show damage early in patients suffering from high blood sugar. These vascular changes in the eye that cause the blood vessels in the back of the eye to leak and damage tissue are a hallmark of diabetes—and can cause blindness.

In 2014, optometrists diagnosed 401,000 cases of diabetes in patients who didn’t know they were suffering from the disease, likely helping to prevent many of these patients from experiencing further health challenges.

This is one of many reasons why it’s important to see your optometrist for a comprehensive eye exam regularly!