(By Dr. Subham Sinha Roy, Consultant VR, Guwahati, Assam)
While India has made triumphant strides towards reducing the prevalence of several communicable diseases, the prevalence of non-communicable diseases has been rising steadily. The prevalence of diabetes, in particular, among adults between 20 and 79 years of age has been growing due to lifestyle, environmental, and genetic factors. Globally, the country has the second highest number of cases of diabetes after China. A study by the Indian Council of Medical Research found that 101 million adults above 20 years of age had the disease and 136 million had prediabetes in 2021.
What Is Diabetes, Diabetic Retinopathy And Diabetes Macular Edema?
Diabetes is a complex metabolic condition caused when the body produces very little or no insulin (the hormone responsible for breaking down sugar into glucose) or becomes insulin resistant leading to elevated blood sugar levels. Diabetes can cause several microvascular and macrovascular complications that can affect crucial organs.
Diabetic retinopathy is one such complication that affects the eyes and can lead to blindness. A complication of diabetic retinopathy which affects nearly one in 14 patients is diabetic macular edema (DME).
Approximately one in 14 people with diabetes has some degree of diabetic macular edema (DME). Understanding how DME develops and affects the eyes in patients with diabetes is important to prevent or treat it.
Understanding DME:
The macula is a slightly oval yellow spot present on the back of the eyeball on the retina. It is a key component responsible for central vision and perceives what is directly in front of the eyeball. Furthermore, the macula helps individuals to see minute details around them such as distinct colours, differences between faces, text on a page, and minuscule movements.
In patients with diabetes, high blood sugar levels adversely affect the blood vessels in the eye, causing them to leak. This causes a build-up of fluid and the retina to thicken, causing DME.
Some of the symptoms are dark spots, difficulty in perceiving colours, blurry or double vision, floaters, seeing straight lines as curved or bent, differences in the perception of an object’s size through one eye, and the inability to see when there is a glare or bright light.
Diagnosis And Treatment Of DME:
Timely diagnosis and treatment of DME are key to preventing disease progression. The diagnosis of DME is made via a comprehensive set of eye tests that test for visual acuity and colour vision. Some of the tests include ophthalmoscopy (which involves using eye drops to dilate the pupils), tonometry (which measures pressure inside the eye), and a slit lamp.
In addition, the doctor may also conduct imaging tests such as fundoscopic examination (Inner, back surface of the eye), optical coherence tomography (which scans and gives visuals of retinal contours and measures retinal thickening and edema) and fluorescein angiography (shows the leaking blood vessels in the retina).
Over the years, several different treatment modalities have emerged for treating DME, but the effectiveness hinges on early detection. Some of the options include steroid therapy and laser treatment. However, these options have several side effects.
Intravitreal injections of anti-vascular-endothelial-growth-factor (anti-VEGF) agents target VEGF-A, a vascular growth factor protein that causes abnormal blood vessels to grow, swell, and leak in DME. However, newer drugs available now target more than one pathway that causes DME. For instance, faricimab is a bi-specific antibody that targets two pathways, i.e. VEGF-A and angiopoietin-2, which are involved in the development of DME and are a safe and effective treatment. Additionally, patients can take several proactive steps to reduce the risk of DME by keeping blood sugar levels in check, consuming a healthy diet, exercising regularly, and managing other chronic conditions such as hypertension.
For individuals with diabetes, it is crucial to understand how DME can affect their eyesight. Awareness and early detection can ensure those affected receive treatment on time, reducing the risk of vision loss. Consulting an ophthalmologist regularly and getting comprehensive eye checkups are an essential part of this journey. Moreover, with the availability of newer treatment modalities for treating DME, patients can look forward to carrying out their daily activities with ease.
[Disclaimer: The information provided in the article, including treatment suggestions shared by doctors, is intended for general informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have regarding a medical condition.]