Diabetes and Your Eyesight

Diabetes is a complex disease resulting from the inability of the body to produce insulin, a hormone that takes sugar out of the blood and into cells where it can be used for energy.

Without enough insulin, there is too much sugar in your blood. It’s like having a car full of gas but no key; you have the fuel you need, but can’t start using it.

Diabetes affects more than 29 million Americans. The most common form of diabetes is adult-onset diabetes. Adult-onset diabetes typically strikes those who are over 40, overweight and have a sedentary lifestyle.

Other risk factors include those with a family history of diabetes and those belonging to certain ethnic groups. Persons of African, Native American, Japanese, Latino or Polynesian descent are more at risk.

Diabetic Eye Disease

A common complication of diabetes is diabetic eye disease. Diabetic eye disease refers to a group of sight-threatening eye problems that people with diabetes may develop.

Glaucoma is one of these diseases.

Diabetic eye disease also includes diabetic retinopathy and cataracts. Diabetic retinopathy, a disease which damages the tiny blood vessels in the retina (the light-sensitive tissue that lines the back of the eye) is the most common diabetic eye disease. Diabetic retinopathy affects nearly 7.7 million Americans age 40 and older.

A cataract is a clouding of the eye’s lens that results in blurring of normal vision. People with diabetes are nearly twice as likely to develop cataracts as other adults. Cataracts also tend to develop at an earlier age.

Diabetes and Glaucoma

The relationship between diabetes and open-angle glaucoma (the most common type of glaucoma), has intrigued researchers for years. People with diabetes are twice as likely to develop glaucoma as are non-diabetics, although some current research is beginning to call this into question. Similarly, the likelihood of someone with open-angle glaucoma developing diabetes is higher than that of a person without the eye disease.

Neovascular glaucoma, a rare type of glaucoma, is always associated with other abnormalities, diabetes being the most common. In some cases of diabetic retinopathy, blood vessels on the retina are damaged. The retina manufactures new, abnormal blood vessels.

Neovascular glaucoma can occur if these new blood vessels grow on the iris (the colored part of the eye), closing off the fluid flow in the eye and raising the eye pressure. Neovascular glaucoma is a difficult disease to treat. One option is laser surgery to reduce abnormal blood vessels on the iris and on the retinal surface. Recent studies have also shown some success with the use of drainage implants.

Protect Your Eyes

Since eye complications are common with diabetes, it is very important that people with diabetes get their eyes examined on a regular basis. The National Eye Institute recommends that people with diabetes get a dilated eye exam at least once a year.

Special thanks to Jorge Alvarado, MD, Professor of Ophthalmology at the University of San Francisco Department of Ophthalmology, San Francisco, California for contributing to this article.