Coding and the Link Between Diabetes, Eye Disease

Written by: Compliance blogger

Diabetes is a leading cause of blindness among working-age adults in the United States. Diabetics are more susceptible to certain eye diseases because their condition can cause irreparable damage to the eyes. However, the Centers for Disease Control and Prevention (CDC) says that about 90% of vision loss from diabetes can be prevented. Diabetic eye diseases include:

Diabetic retinopathy;

• Diabetic macular edema;
• Cataracts; and
• Glaucoma

Although having diabetes does increase the chance for vision loss and blindness from diabetic eye diseases, there are steps that can be taken to prevent diabetic eye disease or to keep it from getting worse.

Diabetic Retinopathy

Diabetic retinopathy is the most common cause of vision loss and blindness in diabetics. In fact, between 40 and 45 percent of those with diagnosed diabetes have some degree of diabetic retinopathy, according to the National Institute of Health (NIH). This is because diabetics have excess sugar in their blood which causes damage to the blood vessels in the retina. The retina is the inner lining in the back of the eye that detects light and turns it into signals that your brain decodes for visual recognition. With diabetic retinopathy, the damaged blood vessels in the retina swell, leak or close off completely.

In the early stage, the blood vessels weaken, bulge, or leak into the retina. This stage is called non-proliferative diabetic retinopathy. There typically aren’t any symptoms at this point but some people may notice subtle changes in their vision, like trouble reading or seeing faraway objects. It is important to keep in mind that those with any type of diabetes can develop diabetic retinopathy and the risk increases the longer one has diabetes.

In later stages, the blood vessels in the retina start to bleed into the center of the eye. This can cause one to see dark, floating spots or cobweb-like streaks. Without treatment, this bleeding can worsen or even cause scarring. As the disease gets worse, some blood vessels close off causing new blood vessels to grow, or proliferate, on the surface of the retina. This stage is called proliferative diabetic retinopathy. These abnormal new blood vessels are weak and can lead to serious vision problems. Untreated diabetic retinopathy can cause other serious eye conditions such as diabetic macular edema, neovascular glaucoma, and retinal detachment.

Diabetic Macular Edema (DME)

Diabetic macular edema also occurs when damaged blood vessels in the retina leak. This causes excess fluid and swelling in the macula part of the retina. The macula is the most sensitive spot in the center of the retina that allows one to see details and is needed for such things as reading, driving and recognizing faces. The accumulation of fluid and swelling of the macula results in blurry vision and can lead to permanent vision loss. Macular edema usually develops in people who already have other signs of diabetic retinopathy.

Cataracts

A cataract is essentially a cloudy lens and causes faded colors and hazy vision. Anyone can get a cataract but it is more likely for diabetics because the excess blood sugar causes deposits to build-up on the lens. In fact, diabetics are 2 to 5 times more likely to develop cataracts. They are also more likely to get them at a younger age. Good control of blood sugar can help prevent permanent clouding of the lens. Otherwise, cataract surgery may be needed to remove lenses that are clouded by the effects of diabetes.

Glaucoma

Glaucoma is a group of diseases that cause damage to the eye's optic nerve. The optic nerve is a bundle of nerves connecting the eye to the brain. Damage to the optic nerve leads to irreversible loss of vision and blindness if not treated early. Remember that untreated diabetic retinopathy can cause abnormal blood vessels that grow out of the retina and block fluid from draining out of the eye with. This leads to fluid build-up and elevated eye pressure causing neovascular glaucoma. According to NIH, having diabetes doubles your chance of having glaucoma.

Risk Factors of Diabetic Eye Disease

Anyone with diabetes can develop diabetic eye disease but the risk is greater with:

• high blood glucose that is not treated
• high blood pressure that is not treated

High blood cholesterol and smoking may also raise the risk for diabetic eye disease. Therefore, controlling blood pressure and cholesterol can also help lower the chance of vision loss. Again, the risk of developing diabetic eye disease increases the longer you have diabetes. Furthermore, some groups are affected more than others. African Americans, American Indians and Alaska Natives, Hispanics/Latinos, Pacific Islanders, and older adults are at greater risk of impaired vision or blindness resulting from diabetes, as reported by the NIH.

Prevention

It’s important for diabetics to get a comprehensive dilated eye exam at least once a year. Early detection is key to taking the necessary steps to protecting the eyes and prevent blindness.

The NIH recommends diabetics manage their diabetes and protect their vision by keeping TRACK:

  T: Take your medications as prescribed by your doctor

  R: Reach and maintain a healthy weight

  A: Add more physical activity to your daily routine

  C: Control your ABCs—A1C, blood pressure, and cholesterol levels

  K: Kick the smoking habit

Indications

Often there are no early symptoms of diabetic eye disease. There may be no pain and no change in vision, particularly with diabetic retinopathy. However, if you do notice sudden changes in vision, it is important to contact a doctor right away.

When symptoms do occur, they may include:

• blurry or wavy vision
• frequently changing vision—sometimes from day to day
• dark areas or vision loss
• poor color vision
• spots or dark strings (also called floaters)
• flashes of light

Treatment

If severe diabetic retinopathy or DME is suspected, a test called a fluorescein angiogram may be performed. This test lets the doctor see pictures of the blood vessels in the retina. When possible, it is important to start treatment right away. While it may not undo any damage already done, treatment may prevent vision loss from worsening.

According to the NIH, doctors may treat advanced eye problems with medicine, laser treatments, surgery, or a combination of these options.

• Injections. Medicines called anti-VEGF drugs can slow down or reverse diabetic retinopathy. Other medicines, called corticosteroids, can also help. These medicines block the growth of abnormal blood vessels in the eye. Anti-VEGF medicines can also stop fluid leaks, which can help treat diabetic macular edema. Anti-VEGF treatments can stop further vision loss and may improve vision in some people.
• Laser treatment. To reduce swelling in your retina, eye doctors can use lasers to make the blood vessels shrink and stop leaking. Laser treatment can keep eye disease from getting worse, which is important to prevent vision loss or blindness. But laser treatment is less likely to bring back vision you’ve already lost compared with anti-VEGF medicines.
• Eye surgery. If your retina is bleeding a lot or you have a lot of scars in your eye, your eye doctor may recommend surgery.

Coding ICD-10-CM

When coding for diabetic-related eye conditions, review to determine whether the patient is diagnosed with Type 1 (E10); Type 2 (E11) or if you need to default to category E13.

Example: Type 1 Diabetes with Ophthalmic complications is E10.3 – as indicated in the table below. Note documentation required to specify the Severity of retinopathy: Mild, Moderate, Severe, Proliferative, etc.

Example: Type 2 Diabetes with Ophthalmic complications is E11.3 – as indicated in the table below. E11 is the “default” category when the type of diabetes is not specified in the patient’s medical record. These are codes specific for retinopathy. Note documentation required to specify the Severity - Mild, Moderate, Severe, Proliferative, etc.:

Category E13 is reserved for “Other Specified Diabetes Mellitus”

E13- codes include diabetes mellitus due to genetic defects of beta-cell function; diabetes mellitus due to genetic defects in insulin action; postpancreatectomy diabetes mellitus; postprocedural diabetes mellitus; and secondary diabetes mellitus NEC. As with the above E10 and E11 categories, E13 has code ranges for ophthalmic complications:

Other Categories of Diabetes Mellitus such as E08; E09 also have sections devoted to reporting ophthalmic complications. The list below categorizes the coding range choices for Diabetes Mellitus.

Code Ranges      Description

E08.00 ‑ E08.9    Diabetes mellitus due to underlying condition

E09.00 ‑ E09.9    Drug or chemical induced diabetes mellitus

E10.10 ‑ E10.9    Type 1 diabetes mellitus

E11.00 ‑ E11.9    Type 2 diabetes mellitus

E13.00 ‑ E13.9    Other specified diabetes mellitus

Conclusion

Even though diabetes is a leading cause of vision loss and blindness in the United States, it can often be prevented. Simply, managing diabetes as directed by a physician and getting recommended eye exams can greatly reduce the risk of developing a diabetic eye disease.

Explicit documentation and assigning specific ICD-10-CM codes to accurately report diabetic eye conditions helps to demonstrate the complexity of the patient’s condition which can warrant a higher level of service for reimbursement purposes.

We hope that you have followed or diabetes blog series and have enjoyed learning about this epidemic and some of its varied complications impacting organ and body systems.