More than 34 million people in the United States have diabetes mellitus (DM), according to the Centers for Disease Control and Prevention (CDC).¹ Further, 4.2 million adults have diabetic retinopathy (DR), reports a recent CDC study.² The leading cause of new cases of blindness in adults, DR affects more than one-third of adults over age 40 who have diabetes.^2,3 About 655,000 have vision-threatening DR.³ In addition, patients with diabetes are at a greater risk for other eye conditions, including macular edema (which usually develops along with DR), cataracts, and glaucoma.

To reduce the risk of long-term complications and prevent acute DM complications (e.g., eye disease, heart disease, kidney disease, nerve damage), risk reduction strategies and continuous medical care are required. However, a recent study reports that 12% to 36% of people with type 2 DM, which accounts for 90% to 95% of all DM cases, do not keep their medical appointments.⁴ These missed appointments pose an increased risk of complications for the patient and add costs to the healthcare system and society.

Here, Leela Raju, MD, a clinical associate professor at NYU Langone Health in New York, NY, answers questions regarding the eye-related risks faced by patients who have diabetes and the importance of complying with regularly scheduled appointments and following a healthy lifestyle. Dr. Raju also serves as secretary of the Eye Foundation of America, an international organization dedicated to creating a world without childhood blindness.

Q: What common eye conditions are patients who have diabetes most at-risk for?

A: Bleeding in the retina, or diabetic retinopathy, is our greatest concern. It can cause permanent damage to the retina, and since we only get one retina and can't replace it like we can other parts of the eye, we need to prevent damage to what we have. Diabetics can also be at greater risk for glaucoma and can develop cataracts earlier than expected.

Q: How do regularly scheduled eye exams help patients who have diabetes maintain vision/eye health and avoid these conditions?

A: By catching any early changes to the retina through at least yearly screenings, we can hopefully prevent permanent damage.

Q: Why is it important for patients who have diabetic eye disease to comply with regularly scheduled visits to the eye care provider?

A: It's easy to forget about the eyes when the changes in vision are gradual, or there isn't any pain — like with diabetes or glaucoma — so the only way to know is to come in and get checked. Even when diabetes is controlled in patients without DR, yearly exams are important so that any subtle changes are caught as early as possible. According to the American Academy of Ophthalmology’s “Diabetic Retinopathy Preferred Practice Pattern,” individuals who have type 2 DM without DR should have an annual dilated eye examination to detect the onset of DR; individuals with type 1 DM without DR should have an annual dilated eye exam beginning 5 years after the onset of diabetes.⁵

I also remind patients that their A1c is more important than a day-to-day sugar reading because it tells me how it's doing over a longer period of time.

Q: How can staff best communicate/educate on the importance of these visits to patients who have diabetic eye disease and/or their care givers?

A: With the early stages of DR, because patients do not experience symptoms or changes in vision, it is important to remind them that they might not notice anything until it's damaging the eye and affecting vision. Explain that we are able to control the amount of damage to the retina due to diabetes, as long as the patient comes in and gets checked — this is why a dilated eye exam is so important.

It also may help to communicate to patients with diabetes the types of testing they can expect during the exam. For example, according to the AAO's Preferred Practice Patterns, the initial examination should include visual acuity, slit-lamp biomicroscopy, intraocular pressure, gonioscopy before dilation (when indicated), pupillary assessment, thorough fundoscopy, examination of the peripheral retina and vitreous.⁵

Optical coherence tomography (OCT) imaging and fundus photography also can be helpful in detecting DM. Fluorescein angiography or OCT angiography provide doctors with images of the blood vessels in the retina. These images can not only help detect issues in the eye, but they may also indicate how the vessels throughout the body are doing, as changes in the vasculature of the eye are likely occurring elsewhere in the body. In addition, looking at the peripheral retina may help catch bleeding that can be missed.

The use of cameras to take widefield images of the retina may be another way to screen patients who have a hard time getting into the office, which may help prevent a delay in care.

Q: What general information about diabetes should the allied health staff provide to the patient who has diabetes or diabetic eye disease?

A: Reminding patients that the A1c is an important number for them to know. In addition, discuss how small changes in their diet — less sugary drinks or less pasta/rice, and more vegetables, fruits, whole grains, legumes, and low-fat dairy products — along with portion control can help control blood sugar and reduce the risk for other diseases.

Also, remind patients that physical activity is an important step that can help lower blood sugar levels and stress levels and may even reduce insulin requirements. Let patients know that exercise doesn't have to be done in a fancy gym or class: it can be something as simple as a walk in the neighborhood or walking in place in front of your TV while watching a 30-minute show.

Steps such as these can help patients understand that there are even small things they can do to help control their sugar and therefore, prevent the damage we see from diabetes. OP

REFERENCES:

1. Centers for Disease and Prevention. National diabetes statistics report, 2020. Centers for Disease Control and Prevention, 2020.
2. Diabetic Retinopathy Fact Sheet. Centers for Disease Control and Prevention. https://www.cdc.gov/visionhealth/pdf/factsheet.pdf . Accessed August 8, 2022.
3. Diabetes and Vision Loss. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/managing/diabetes-vision-loss.html#:~:text=Macular%20edema%20is%20the%20most,retinopathy%20will%20develop%20macular%20edema . Accessed August 8, 2022.
4. Sun CA, Taylor K, Levin S, Renda SM, Han HR. Factors associated with missed appointments by adults with type 2 diabetes mellitus: a systematic review. BMJ Open Diabetes Res Care. 2021;9(1):e001819. Published online Mar 5, 2021.
5. Flaxel CJ, Adelman RA, Bailey ST, et al. Diabetic Retinopathy Preferred Practice Pattern [published correction appears in Ophthalmology. 2020 Sep;127(9):1279]. Ophthalmology. 2020;127(1):P66-P145. https://www.aaojournal.org/article/S0161-6420(19)32092-5/fulltext . Accessed August 8, 2022.