Diabetes mellitus is a chronic disease that, if not properly treated, can generate multiple complications in those who suffer from it. One of them, diabetic retinopathy, an eye condition that occurs when frequent and high levels of glycemia (blood sugar) cause damage to the blood vessels of the retina, which is the layer of light-sensitive tissue located in the posterior part of the eye, through which we can make the distinction of everything we see.
To maintain eye health, it is necessary to know the causes of diseases such as diabetic retinopathy, which can lead to progressive or total loss of vision. Retinopathy can cause the blood vessels in the back layer of the eye to swell or close, preventing blood from flowing; and it can even generate new and abnormal blood vessels in the retina, causing visual impairment or blindness.
Stages of retinopathy
Retinopathy or diabetic eye disease occurs in two stages. One is non-proliferative diabetic retinopathy (NPDR), an early phase in which many small blood vessels leak and cause the retina to swell, including the macula — a yellow spot that is responsible for fine, detailed vision; thanks to this we can read and distinguish faces —causing macular edema. When a person has non-proliferative diabetic retinopathy, their vision becomes blurred.
The other stage is proliferative diabetic retinopathy (PDR), which is understood as the most advanced phase of diabetic eye disease. It appears when the retina develops new blood vessels in an abnormal process called neovascularization. These new, fragile vessels often bleed into the vitreous, which can partially or totally block vision.
Diabetic retinopathy symptoms
In general, retinopathy has no symptoms at the beginning, so a person can have this disease and not know it. However, diabetic retinopathy, which usually affects both eyes, can manifest itself at some point through symptoms such as:
- Blurry vision
- Vision that alternates between blurry and light (white or dark areas are projected into the field of view)
- Poor night vision
- Notice that the colors are dimmed or dull
- Temporarily lose vision
There are risk factors that can precipitate the appearance of retinopathy in patients with diabetes. Here are some:
- Diabetes evolution time.
- Poor glycemic control.
- High cholesterol.
- Kidney damage.
- High blood pressure.
More prevention, better vision
According to the World Health Organization (WHO), more than 75% of those who have had diabetes for more than 20 years have some form of diabetic retinopathy. The WHO points out that after 15 years of a patient having received the diagnosis of diabetes, on average, 2% are blind, while 10% have a severe visual impairment.
However, diabetic retinopathy, like other complications of diabetes mellitus, can be prevented in various ways; for example, by carrying out periodic eye examinations to detect alterations in the vessels of the retina in time.
Both early detection and timely and adequate treatment of this eye condition can prevent or delay the appearance of blindness. According to the WHO, there are effective treatments, based on scientific evidence, that significantly reduce - by more than 90% - the risk of moderate decrease in vision and blindness.
It is important to know that through adequate metabolic control, the onset and evolution of diabetic retinopathy can be delayed. Maintaining a healthy diet, exercising moderately, and following your treating physician's instructions — to ensure that your blood glucose levels are within the appropriate range, from 70mg / dl to 100mg / dl on an empty stomach - is then the first step to avoid diabetic retinopathy and its complications.
American Academy of Ophthalmology [website]. What is diabetic retinopathy? [published on October 24, 2019; accessed January 2, 2020]. Available at: https://www.aao.org/salud-ocular/enfermedades/retinopatia-diabetica
World Health Organization [website]. What is diabetes [accessed January 2, 2020]. Available at: https://www.who.int/diabetes/action_online/basics/es/index3.html
World Health Organization [website]. Blindness [accessed January 2, 2020]. Available at: https://www.paho.org/hq/index.php?option=com_content&view=article&id=13693:prevention-blindness-eye-care-blindness&Itemid=39604&lang=en