Addressing the Growing Burden of Diabetic Retinopathy: Challenges and Innovations in Screening

Editor:

Rachelle Srinivas, DO

Dr. Rachelle Srinivas is a neuro-ophthalmology fellow at Michigan State University. She is the current Director of Public Health in OGT.

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The increasing prevalence of diabetes mellitus has led to a rise in microvascular complications, including diabetic retinopathy (DR), which can cause a range of retinal vascular abnormalities, with the most severe cases resulting in significant visual impairment (1). 

INTRODUCTION

In 2020, approximately 3.28 million people worldwide suffered from visual impairment due to diabetic retinopathy [2], with Africa reporting the highest prevalence, followed by North America and the Caribbean [3]. The burden of DR is expected to continue to increase, with a projected worldwide prevalence of 160.50 million by 2045 [3]. 

Globally, low- and middle-income countries bear a heavier burden of the disease, with regions of highest prevalence often facing limited access to healthcare. Diabetic retinopathy is a major cause of visual impairment, particularly among working-age adults. Among those affected by DR, females have been found to have a higher prevalence of DR and a more significant increase in blindness due to DR compared to males [2, 4, 5]. 

SOURCE OF DISPARITY

The rise in patients with diabetes is expected to disproportionately affect low and middle-income counties compared to high-income counties [2, 6, 7]. Many areas with a high prevalence of DR are also associated with limited access to healthcare and inadequate resources and management [2]. Additionally, the prevalence of DR is associated with reduced economic productivity and educational and employment opportunities, further exacerbating the challenges these patients face [2]. 

PREVENTION METHODS EMPLOYED TO ADDRESS THE ISSUE

Early screening and treatment of DR are essential to reduce the risk of patients developing severe irreversible visual impairment [2]. The implementation of improved screening methods and effective therapeutic strategies in high-income countries has resulted in reduced rates of DR-related visual impairment. However, low—and middle-income settings face the challenges of a high burden of disease coupled with low resources [2].

TELEMEDICINE

Recent technological innovations, such as telemedicine and portable devices provide promising methods to increase the accessibility of screening services [8, 9, 10, 11, 12, 13]. Telemedicine allows for increased accessibility of screening as ophthalmologists can remotely evaluate digital fundus photography and provide suggestions for further follow-up and treatment [8, 13]. Studies evaluating the use of telemedicine for DR screening have shown promising results with high patient satisfaction and the ability to detect disease early [13]. Additionally, telemedicine can help providers meet the high need for screening that might otherwise prove challenging due to the limited availability of office visits. 

PORTABLE SCREENING DEVICES

There is also ongoing research evaluating the utility of portable devices such as handheld fundus cameras and smartphone-based fundus cameras for screening, and these tools have been implemented in screening initiatives in low-income regions [8, 10, 11, 13, 14]. Such portable devices provide a cost-efficient alternative to traditional fundus cameras and have the added benefit of easy portability without extensive training needed for operators [8, 9, 10, 11, 12]. The Zeiss Visuscout 100, Optomed Aurora, and Volk Pictor Plus are three models of handheld fundus cameras that have shown promising results so far and have been shown to capture photos that are of sufficient quality for DR screening [10, 11, 12, 14]. Several smartphone-based devices and imaging systems have also shown encouraging results [9, 14]. 

ARTIFICIAL INTELLIGENCE

In addition, the emerging rise in artificial intelligence (AI) has also led to efforts to incorporate AI with screening [15]. Studies have found encouraging results regarding DR detection by AI algorithms [6]. The use of AI for DR screening could further help alleviate the mismatch between the high burden of disease and a limited number of providers, and it could also allow for faster provision of results so patients can receive timely referrals and treatment as needed. 

CONCLUSION

Visual impairment due to the complications of diabetic disease is a concerning public health issue that is projected to increase in prevalence and disproportionately affect low and middle-income countries. Fortunately, screening and timely treatment can effectively improve patient outcomes, and there are exciting innovations and methods that can contribute to the accessibility and cost-efficiency of screening efforts.

REFERENCES

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