An Overview of Diabetic Macular Edema

Nancy Holekamp, MD: Hello and welcome to this HCPLive® Peer Exchange titled, “Clinical Management of Diabetic Macular Edema.” I am Dr Nancy Holekamp, director of retina services at the Pepose Vision Institute in Chesterfield, Missouri. Joining me today are my colleagues, Dr Joseph Coney of the Retina Associates of Cleveland in Cleveland, Ohio; Dr Theodore Leng, associate professor of ophthalmology at Stanford University School of Medicine, Palo Alto, California; and Dr Ehsan Rahimi of the Palo Alto Medical Foundation and adjunct faculty at Stanford University Department of Ophthalmology in Palo Alto, California. Today, we will discuss several topics pertaining to the clinical management of diabetic macular edema [DME]; we will review the clinical data and discuss optimal management. The first segment of this presentation will be an overview of diabetic macular edema. We can start by defining diabetic macular edema. Dr Coney, you can begin with a good definition for diabetic macular edema.

Joseph M. Coney, MD: It’s important to know that many Americans with diabetes will develop diabetic retinal disease, and as part of that spectrum, we have diabetic macular edema. Diabetic macular edema typically means leakage or swelling in the back of the eye. It is a leading cause of blindness, and it mostly affects working-age populations. It affects 1 to 3 individuals with diabetes who are over the age of 40, and 50% of people who have diabetic retinopathy will develop diabetic macular edema. Diabetic macular edema can occur at any time over the course of diabetic retinopathy. When we see a patient with diabetes, there’s a spectrum of diseases that the patient may present with. As the level of the disease progresses, diabetic macular edema becomes more likely. For example, if someone has mild nonproliferative diabetic retinopathy, which is our earliest form of diabetic retinopathy, there is about a 30% chance over 4 years that they will develop diabetic macular edema. As the disease progresses to more severe levels of nonproliferative disease, they have up to a 60% chance of developing the same complications. Earlier on, because the disease may be mild, they may not have any symptoms, but as time progresses, driving and reading may be affected. In the later stages of the disease, they may notice new onset of floaters and sudden loss of vision from tractional retinal detachments, and diabetic vitreous hemorrhages.

Nancy Holekamp, MD: That was a great summary and definition of diabetic macular edema and the patients who develop it. In my experience from our clinical trials, many patients who are enrolled in clinical trials for diabetic macular edema are in their early 60s, they’ve had diabetes for about 15 years, and it hasn’t always been under control. I think of that as the typical person who might show up in our office with diabetic macular edema. Dr Leng, what are your insights on which health care providers are usually making the first diagnosis of DME?

Theodore Leng, MD, FACS: It depends on your geography, the demographics of your environment, and who’s taking care of these patients. Patients with DME can present to multiple types of eye care providers. Many Americans receive their primary eye care through their optometrist, and so they may be the ones who are doing the annual diabetic screenings, and looking for evidence of mild nonproliferative disease. At that time they may notice signs of diabetic macular edema, such as exudates or cholesterol leakage in the macula. Those patients might get referred to a specialist for evaluation and treatment. Many Americans receive their annual exams with their primary ophthalmologist, whether it’s a comprehensive ophthalmologist, and some are referred to retina doctors for their screenings. It could be any one of these providers in the eye care space who’s noticing the DME.

Nancy Holekamp, MD: You are a retina specialist at an academic institution; are most patients with diabetic retinopathy coming to you from optometrists, comprehensive ophthalmologists, or perhaps endocrinologists?

Theodore Leng, MD, FACS: In our institution, it’s a combination of endocrine and primary care. We’ve set up a teleophthalmology screening program with our primary care partners in the community and placed nonmydriatic, meaning no dilation needed, cameras in their offices. That’s how we conduct our outreach to screen as many people as possible to increase the screening rate. While this is not the focus of this forum, the screening rate in many areas in America is low as 30% to 50%. We want to extend the care to more people who need it.

Nancy Holekamp, MD: Dr Coney, you’re in a well-known private practice with all retina doctors, so where do most of your referrals of patients with diabetic macular edema come from?

Joseph M. Coney, MD: We cover all of northeastern Ohio, so it depends on what’s going on in that area. I look at diabetes in terms of zip codes. Sometimes we look at it from ethnicity, but I think zip codes are important because people in certain zip codes have the same type of disease. For example, in Cleveland, or in Ohio, there is a 13% chance of having diabetes, but in Youngstown or Trumbull county, that population may be at 20%, but there’s a certain population that may be as high as 60%. It depends on where I am. Most patients are likely coming from an optometrist, as we have a large optometric referral network. They’re sometimes the first people who diagnose individuals with diabetes. Unfortunately, in Ohio, screenings are less than 50%, and those numbers are even less in underserved populations, where most of my Black and Hispanic patients come from.

Nancy Holekamp, MD: It’s good to review these referral patterns and how patients with DME are getting to the doctors who take care of them.

Thanks to all of you for this rich and informative discussion, and thank you for watching this HCPLive® Peer Exchange. If you enjoyed the content, please subscribe to our e-newsletters to receive upcoming Peer Exchanges and other great content right in your inbox.

Transcript edited for clarity.