In the West and other developed countries, it’s often easy to forget that not so long ago being overweight wasn’t the norm, obesity was rare, and a whole host of diseases attributed to poor lifestyle choices weren’t common. Alas, bad diets and junk food, decreased levels of exercise, and a number of other issues have made diseases related to lifestyles like diabetes all the more common. They say that when the United States sneezes the rest of the world catches a cold… So when the country adds another inch to its waistline does the planet then realize that its blood sugar levels are rising dangerously fast?
It’s a metaphor of course but it stands up to scrutiny. As countries experience increased development and approach Western standards of living they often experience a rise in lifestyle-related conditions like diabetes. In ophthalmology, we then observe an increase in ocular complications like diabetic retinopathy (DR), a complication caused by high blood sugar levels that damage the retina. Patients usually experience little to no symptoms as the retina slowly sustains damage until they began to experience vision problems and/or vision loss, making early diagnosis absolutely crucial.
As Africa continues its economic development, diabetes becomes an increasingly problematic health issue, with the number of people with the disease in sub-Saharan Africa projected to increase from 19.4 million in 2019 to 47.1 million by 2045. Out of this population, it’s estimated that 35% of people with diabetes will have some form of DR and about 10% have vision-threatening DR, either proliferative DR or diabetic macula edema (DME). As we’ve mentioned DR often exhibits few symptoms, and as most blindness caused by DR can be prevented through early detection, screening is of the utmost importance.1
Stopping a Diseases Without Symptoms
But how do you do that in a continent such as Africa, populated by countries that often have severely lacking healthcare infrastructure and rural populations that are difficult or impossible to reach by conventional methods, to name a mere couple of problems? That’s the task faced by the Diabetic Retinopathy Network (DR-NET), established in 2014 by the Queen Elizabeth Diamond Jubilee Trust to prevent avoidable blindness across the Commonwealth. This group is comprised of countries that are predominantly former British colonies, and the program partners eyecare professionals in low- and middle-income countries, particularly in Africa, with clinics in the United Kingdom, to improve the quantity and quality of eye care training and service delivery.
Eight countries in Africa are included in this network which is aiming to establish, implement and improve DR screening and treatment services. The different DR programs on the continent have adapted and implemented methods of screening, referral and treatment to their resource-limited context, sharing challenges and solutions with each other through the DR-NET. These projects have collectively screened over 190,000 people with diabetes and have treated more than 37,000 with vision-threatening diabetic retinopathy (VTDR). In Africa, 21 DR centers screened 117,000 people with DM and treated over 20,000 for VTDR.1
While these numbers are impressive on their own they’re a pin-drop continentally speaking, and DR-NET has pointed out that there is a paucity of evidence and research on DR in Africa. It’s currently considering research papers in two countries that are part of its network.
The first is a case study on a partnership set up to improve the development of DR national guidelines in Ghana, and the second focuses on the rationale for integrating DR services into pre-existing diabetic services in Kenya. There’s also a separate case study from both Ghana and Uganda on the outcomes and challenges of using anti-VEGF for the treatment of diabetic macular edema, which should also make for good reading.
Insights from Samba Land
While we wait for more information about these studies, can we postulate how well increased DR screening will work long term, are there studies in (fairly) comparable locations that we can examine? Of course, there are we wouldn’t be cruel to you, and we took a look at Feasibility of Screening for Diabetic Retinopathy Using Artificial Intelligence in Brazil, which was only published in October last year. The study used an artificial intelligence (AI) device that was embedded in a portable retinal camera and was centered in Sergipe State, an area characterized by high rates of poverty and illiteracy with no specialized retina care.
Despite screening being offered free of charge in a convenient location for locals, from a total of 2,052 eligible individuals, only 1,083 attended the screening. The researchers stated that this highlighted the socioeconomic barriers that prevent access to eye examination in the poorest regions of Brazil. The image acquisition was performed by trained healthcare technicians, with automatic evaluation by the system, and instant remote evaluation by retinal specialists in selected cases.2
With such low levels of uptake amongst the local populace it’s not surprising that the researchers behind the Brazillian study concluded that lack of awareness about diseases, complications, and prevention among the public is a major issue. They said that comprehensive efforts and communication campaigns should therefore be made to engage members of the lay community to increase awareness and adherence rates, both about diabetes generally and its ocular complications specifically. They also recommended using home screenings for patients unable to go to the examination site, whenever feasibly possible.2
Given the relative similarity between Sergipe State and much of the continent of Africa (high levels of poverty, low educational attainment, and literacy, widespread lack of medical knowledge and awareness, etc), we can predict that DR-NET’s efforts could run into the same challenges. Time will tell whether or not they’ll be able to overcome them and we’ll be keen to learn more about the network’s studies in Kenya and Ghana, and how well they’ll compare to their Brazillian counterpart. While strong positive results with good outcomes for patients may be some time away, if clinicians are able to educate more Africans about the dangerous ocular consequences of diabetes, they should be able to save vision and lives as the continent’s waistline begins to expand.
- Bascaran C, Zondervan M, Walker C, Astbury NJ, Foster A. Diabetic Retinopathy in Africa. Eye (Lond). 2022;36(Suppl 1):1-3.
- Malerbi FK, Melo GB. Feasibility of Screening for Diabetic Retinopathy Using Artificial Intelligence, Brazil. Bull World Health Organ. 2022;100(10):643-647.