Introduction:
Diabetes mellitus is one of the chronic and fastest-growing diseases leading to vision loss. It is more common in middle and old age people. According to the World Health Organization (WHO), it was estimated that from 1999 to 2010, diabetes retinopathy ranked fifth most common cause of visual impairment. Several people's diabetes from 170 million in 2000 to 365 million by 2030. Diabetes retinopathy is a condition that damages the blood vessels at the retina, leading to blindness and vision loss.
Vision-threatening diabetic retinopathy (VTDR), which includes proliferative diabetic retinopathy, non-proliferative diabetic retinopathy, and diabetic macular edema rise to 190 million and 56 million by 2030. The prevalence of the condition increases with the duration of poor glycemic control and diabetes.
The common risk factors include hyperglycemia, diabetes, and hypertension. Control of serum glucose is effective in reversing vision loss. It is common both in developed and developing countries. The article discusses the prevalence of diabetes retinopathy, its incidence, progression, risk factors, causes, symptoms, diagnosis, and treatment.
What Is Diabetic Retinopathy?
Diabetic retinopathy is an eye condition that damages the blood vessels in the retina. The two stages of diabetic retinopathy are as follows:
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Proliferative Diabetes-Related Retinopathy: This occurs when the new blood vessels grow. These new blood vessels leak into the gel-like substance known as vitreous. The bleeding blocks the vision.
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Non-proliferative Diabetes-Related Retinopathy: It is in the early stage and occurs in diabetic people. The blood vessels leak into the retina. This manifests with either bleeding, fluid, or lipid. It can lead to poor blood flow.
What Is the Prevalence of Diabetic Retinopathy Globally?
According to the WHO, it was estimated that diabetes retinopathy accounts for 37 million cases of blindness. Between 1980 and 2008, a study was conducted on population-based studies in the United States, Europe, Australia, and Asia. The study showed the condition's prevalence was 35 percent with visually threatening diabetic retinopathy.
Type 1 Diabetes:
The prevalence was reported to range from 10 to 50 percent, depending on the method and population used for screening for diabetic retinopathy. A European study reported the prevalence of the condition among type 1 diabetes people ranged from 20 percent in Austria to 60 percent in Portugal. A study from the United States reported that the prevalence of diabetic retinopathy and visually threatening diabetes retinopathy ranged from 80 to 30 percent.
The prevalence of this condition is lower in Asia, with the lowest in India. The prevalence ranged from 25 to 40 percent in New Zealand and Australia. The prevalence varies with time because of improved health care.
Type 2 Diabetes:
The prevalence of diabetic retinopathy and visually threatening diabetic retinopathy were 25 and seven percent. The prevalence in other European countries, such as Denmark, Sweden, and Italy, ranges from 30 to 40 percent. In China, the prevalence of diabetic retinopathy is higher in rural areas than in urban areas. In India, the disease prevalence is higher at 28 percent in urban areas and 19 percent in rural areas. The Singapore study revealed that the prevalence of the disease is higher (33 percent) in migrants who lived in Singapore than in urban areas. The new migrant Indians in Singapore experience new dietary habits and lifestyle changes. Psychological factors like stress and financial resources complicate these.
What Is the Incidence and Progression of Diabetic Retinopathy?
Type 1 Diabetes:
In Europe, 50 percent of people develop retinopathy in five to seven years, and ten percent would develop proliferative diabetic retinopathy by five years. According to the United States study, the incidence was 74 percent and increased to 94 percent after 25 years.
Type 2 Diabetes:
In the UK, the incidence of type 2 diabetes mellitus was four percent and increased to 16 percent after ten years. The annual incidence of diabetic retinopathy in the United States was seven percent.
What Are the Risk Factors of Diabetic Retinopathy?
The risk factors of diabetic retinopathy are divided into modifiable and non-modifiable factors. The risk factors are as follows:
Modifiable Risk Factors:
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Hyperglycemia: It is the most common risk factor. The control of glycemia (less than seven percent) reduces the risk of progression of diabetic retinopathy.
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Hypertension: Tight blood pressure in type 2 diabetes patients reduces the risk of progression of diabetic retinopathy by 37 percent.
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Dyslipidemia: Statin affects glucose homeostasis, increasing insulin resistance and decreasing insulin production.
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Obesity: It affects type 1 diabetes mellitus.
Non-modifiable Risk Factors:
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Puberty: Post-pubertal period are at increased risk of developing diabetic retinopathy.
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Pregnancy: It increases the risk of diabetic retinopathy. Pregnant women are at higher risk of disease progression.
How Can Diabetic Retinopathy Be Diagnosed?
The eye doctor can diagnose the condition by visual acuity (to check vision clearance). The doctor may check the peripheral vision by seeing from the sides of the eyes. The eye muscle function can be checked by moving the patient's eyes.
How Can Diabetic Retinopathy Be Managed?
The health care provider may create a treatment plan based on age, medical history, visual acuity, and extent of retinal damage. The treatment options include corticosteroid injections, laser surgery, and vitrectomy. A vitrectomy is a surgical procedure in which the surgeon makes a small incision in the eye and repairs the blood vessels.
How Can the Prevalence and Incidence of Diabetic Retinopathy Be Declined?
Increasing personal awareness, access to screening programs, and better glycemic control reduce the prevalence and incidence of diabetic retinopathy in developed countries like the United States, European countries, and Australia. Further, the prevalence and incidence can be decreased by avoiding smoking, exercising regularly, annual eye examinations, and controlling blood sugar levels.
Conclusion:
Diabetic retinopathy is a common complication of diabetes mellitus affecting the eyes. It can lead to blindness and vision loss. In 2020, the global prevalence of the condition was around 27 percent. The prevalence is highest among Middle East Asia and Africa and lowest in Europe and North America. The main risk factors of diabetic retinopathy are obesity, puberty, pregnancy, physical inactivity, and poor diet. Treatment modalities and screening can prevent vision loss and improve outcomes.
