The diabetic eye disease also known as diabetic retinopathy is caused by high blood sugar due to diabetes (diabetes mellitus) leading to vision loss in both eyes.
Symptoms may include, blurry vision which sometimes fluctuates, poor night vision, seeing faded colours and vision loss.
The high blood sugar damages the retina, which is part of the eye that detects light and sends signals to the brain.
While sugar diabetes damages blood vessels in the body and can be controlled, the loss of sight as a result of diabetic retinopathy can be controlled to avoid the double tragedy.
According to the World Report on Vision (2019), globally 116 million adults are affected with diabetic retinopathy.
Due to the changing lifestyles, the number of people affected is estimated to increase to 180 million by 2030.
Historically more attention has been given to cataract and uncorrected refractive error eye conditions, however diabetic retinopathy is a leading cause for avoidable blindness.
In less resourced settings the risk of diabetes is increasing, poverty and lack of awareness affects access to eye care services and prohibits early intervention leading to vision loss.
The risk of having diabetic retinopathy increases with the duration of having diabetes.
It is also estimated that at least half of the people with diabetes will end up having diabetic retinopathy and pregnant women with diabetes are at higher risk. According to the ministry of Health and Child Care in Zimbabwe, 10 in every 100 people have diabetes.
The Lancet Global Health Commission has reported that the number of people with diabetes is increasing thereby increasing diabetic retinopathy-related blindness.
Management and treatment options
Prevention is better than cure therefore, lifestyle management can have significant effects on the control of blood sugar and associated risks.
Patients should be encouraged to manage their diet and maintain a healthy weight, however it is important to be cognisant of individual needs, culture and quality of life.
The aim is to manage blood sugar and reduce the risk of developing diabetic retinopathy.
Routine eye screening, preferably on an annual basis is recommended and this should include a full eye examination.
Patients often present late for screening, diagnosis and treatment which makes it difficult to prevent severe vision loss or blindness. The treatment manages the progression and preserves sight, however if the intervention is late, sight cannot be restored.
Diabetic retinopathy is progressive, and includes non-proliferative retinopathy which is the early stage causing blood vessels to swell and leak.
Proliferative retinopathy is an advanced stage that requires either laser treatment or surgery to avoid vision loss.
A diabetic screening, treatment programme should be developed and consistent treatment can restore some of the vision.
Laser treatment helps to seal leaking blood vessels and reduces the swelling and sometimes more than one laser treatment is required.
Medicines can be injected in the eye to stop the growth of abnormal vessels and to treat the swelling.
Vitrectomy is a procedure that removes the gel-like substance at the centre of the eye and is considered an option when laser treatment and injections have failed.
Recommendations
The integration of eye care services into the primary health services is essential in increasing the coverage and access to services for eye conditions such as diabetic retinopathy.
Eye institutions still face the challenges of accessing eye equipment such as laser machines and measures should be made to invest in such equipment. Delivering integrated people centred-eye care (Ipec) will shift the balance of care, addressing inequalities in access and ensuring services are provided in the communities, closer to the patients.
Strengthening the linkages and referral system enhances diabetic management from screening, diagnosis and treatment. Diabetic retinopathy is difficult to spot early and a person can go for some time without showing symptoms hence the importance of monitoring and following the patient’s journey.
Many systems fail because patients are lost along the referral pathway. It is known that most eye care services in low to medium income countries are provided at secondary and tertiary institutions.
In light of the risk to vision loss, establishing a nationwide screening programme is necessary for early detection and treatment and will reduce the patient out of pocket payments.
Alternatively, one stop centres can be established, promoting access to diabetes services at the same time screening for diabetic retinopathy. It is therefore imperative to build the resource capacity at all levels of care. Diabetic retinopathy affects adults and mainly the work force which leads to loss of productivity. Guidance should be provided in managing social and environmental determinants such as diet, activity and obesity. Employers should invest in wellness programmes to reduce the risk.
Traditionally eye health personnel have supported the screening and referral of patients with diabetic retinopathy.
However, the adoption of artificial intelligence such as the use of a retinal image taken with a camera with the right software to support the grading and referral of patients will enhance efficiency and manage work flow. Myths and misconceptions surrounding visual impairment and blindness need to be addressed to improve acceptance and uptake of services for lifelong care.
This will entail developing key messages to raise awareness on diabetic retinopathy, risks and services available. Further, developing guidelines on managing diabetes and diabetic retinopathy is useful for integrating into structured programmes, education and self-monitoring.
The Zimbabwe National Eye Health Strategy (2021-2025) has highlighted the need to address diabetic retinopathy.
Diabetes is an emerging epidemic and according to the STEPS survey conducted in 2005 it was estimated that 10% of the population are living with diabetes mellitus, 28.4% of those living with diabetes will have diabetic retinopathy and of them 5% would become blind.
Investment into population based surveys will provide information on the number of people affected to guide planning and responsive eye care programmes.
Implementing evidence-based strategies will be more sustainable and will address context specific needs ensuring affordable, quality and accessible diabetic retinopathy services.
The World Health Organisation (2015) tool for the assessment of diabetic retinopathy and diabetic management systems (TADDS) is a useful resource for conducting a situational analysis to determine the resources, capacity, systems, quality and equity. Resources are limited and the collaboration of different stakeholders is essential in managing a diabetes and diabetic retinopathy programme.
- *Tigere is a development practitioner and writes in her personal capacity.
- These weekly articles are coordinated by Lovemore Kadenge, an independent consultant, managing consultant of Zawale Consultants (Private) Limited, past president of the Zimbabwe Economics Society and Chartered Governance & Accountancy Institute in Zimbabwe.- kadenge.zes@gmail.com or mobile: - +263 772 382 852