Diabetes comes with a lot of complications, both on the macrovascular and microvascular scale.
Macrovascular complications, as the term suggest, involve the large blood vessels and under this category falls cardiovascular problems such as heart disease and hypertension and stroke.
But what about micro vascular complications? This category includes
- Effect on the eye (aka diabetic retinopathy or diabetic eye disease)
- Effects on the kidney (aka diabetic nephropathy or chronic kidney disease)
- Effects on the peripheral nerve function
- Effect on sexual function (e.g. erectile dysfunction)
In the next couple of posts we will look at the most common microvascular complications of diabetes starting with diabetic retinopathy.
Diabetic retinopathy is the most common cause of vision loss among adults in the US. It occurs when the retina is damaged through microvascular complications of diabetes.
The retina is the located at the back of the eye. It is the light-sensitive part of the eye. Diabetes can cause damage to the small blood vessels of the retina. Damage can occur in several ways. One way is the swelling and leaking of fluid from the blood vessels. Another way is the formation of new blood vessels (angiogenesis) of the retina. Either way, the retina gets damaged leading to visual impairment and blindness.
Diabetic retinopathy occurs in 4 stages:
- Mild Nonproliferative Retinopathy. At this earliest stage, microaneurysms occur. They are small areas of balloon-like swelling in the retina’s tiny blood vessels.
- Moderate Nonproliferative Retinopathy. As the disease progresses, some blood vessels that nourish the retina are blocked.
- Severe Nonproliferative Retinopathy. Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment.
- Proliferative Retinopathy. At this advanced stage, the signals sent by the retina for nourishment trigger the growth of new blood vessels. This condition is called proliferative retinopathy. These new blood vessels are abnormal and fragile. They grow along the retina and along the surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they have thin, fragile walls. If they leak blood, severe vision loss and even blindness can result.
In its early stages, diabetic retinopathy often does not present with any evident symptoms. Yet, about 40 to 45% of those diagnosed with diabetes (type 1 and type 2) eventually develop diabetic retinopathy. This is why people with diabetes are recommended to undergo a comprehensive dilated eye exam at least once each year.
With preventive measures and close monitoring, the risk for vision loss can be reduced by 95%. “The Diabetes Control and Complications Trial (DCCT) showed that better control of blood sugar levels slows the onset and progression of retinopathy.” Early detection also reduces the risk for disease progression. Currently, there are many treatment options available. IN addition, blood pressure and cholesterol levels should also be kept under control.
Laser surgery is used to shrink abnormal blood vessels. Types of laser surgery are scatter laser and focal later treatments.
Vitrectomy is a more invasive procedure.
“A vitrectomy is performed under either local or general anesthesia. Your doctor makes a tiny incision in your eye. Next, a small instrument is used to remove the vitreous gel that is clouded with blood. The vitreous gel is replaced with a salt solution. Because the vitreous gel is mostly water, you will notice no change between the salt solution and the original vitreous gel.”
Things that can exacerbate retinopathy
Pregnancy can exacerbate diabetic retinopathy in women with diabetes. In a recent study, alcohol consumption was linked to increased risk of deterioration of visual acuity.