Reducing the frequency of eye screening in patients with diabetes from annually to every other year would delay detection of sight-threatening diabetic retinopathy (STDR) and proliferative diabetic retinopathy (PDR), according to real-world data from a multi-ethnic population-based retrospective cohort study.
Among over 82,000 patients with diabetes in the London area, diagnosis of STDR would have been delayed by 1 year in 56.3% of patients, while diagnosis of PDR would have been delayed in 43.6%, reported Christopher Owen, PhD, of St. George’s University of London, and colleagues in the British Journal of Ophthalmology.
“These delays, particularly among those with the most serious diabetic eye disease — those with PDR — could easily result in sight loss,” Owen told MedPage Today.
An estimated 7.7 million people in the U.S. suffer from diabetic retinopathy, a leading cause of blindness. The American Diabetes Association and the American Academy of Ophthalmology Retina Panel recommend routine dilated eye exams for patients with diabetes starting 5 years after diagnosis for type 1 diabetes and at the time of diagnosis and annually (or every 2 years) thereafter for type 2 diabetes.
Owen and colleagues conducted their analysis in light of a 2016 U.K. recommendation to reduce the frequency of diabetic eye screening from annually to once every 2 years, as it is considered “safe and cost-effective, potentially reducing the number of appointments and workload,” they wrote. However, they noted “while biennial screening among those at low risk of sight loss has been approved, uptake thus far has been limited (despite the potential resource and cost savings).”
Of note, several groups would have had higher rates of delayed diagnoses if annual screening was changed to biennial, including Black patients and those in the youngest and oldest age groups.
The standardized cumulative rates of delayed STDR diagnoses per 100,000 persons for each ethnic group were 1,904 for Black people, 1,276 for South Asian people, and 844 for white people. For PDR diagnoses, the overall numbers were much lower, but rates were still higher among Black people (90 per 100,000) compared with white (46 per 100,000) and South Asian people (44 per 100,000).
Delayed STDR events per 100,000 persons were highest among those younger than 45 and those 65 and over — 1,504 and 1,248 events versus 1,178 for those ages 45 to <55 years and 987 for those ages 55 to <65 years. There were fewer PDR events among the youngest age groups (36 per 100,000), but markedly more among the oldest age group (95 per 100,000).
“This was not surprising as we know these groups have higher rates of diabetes complications,” Owen said. “The youngest age groups may not control their diabetes as well as they should, and older people may be at increased risk of complications due to other health conditions.”
“Those of Black ethnic origin may be at higher risk of diabetes complications due to differences in health and lifestyle, which may mean they are more susceptible,” he added. “Delays in seeing these people will result in more being identified at a later stage when they are at greater risk of sight loss.”
In an interview with MedPage Today, Ninel Gregori, MD, of the University of Miami Miller School of Medicine in Florida and a clinical spokesperson for the American Academy of Ophthalmology, said the study is valid and “provides interesting information on healthcare disparities among different ethnicities. It also adds additional information regarding the need for annual screenings.”
Gregori noted that screening can be conducted via a full eye examination with dilation of the pupil or via a diabetic teleretinal screening, in which a picture of the retina is read by an eye professional. “We need to improve access to teleretinal screening, which should be done via a camera in primary care physician offices. That should be part of the routine diabetic evaluations. We also need to think about utilizing AI for screening purposes to make it more affordable.”
For this study, Owen and colleagues included 82,792 patients in North-East London who were screened from 2012 through 2021. All patients had no diabetic retinopathy on two prior consecutive screening visits with up to 8 years of follow-up.
Mean age at baseline was 56.7, 52% were men, 37% were white, 36% were South Asian, and 16% were Black. Nearly all of the patients (95%) had type 2 diabetes.
Over a mean of 4.3 years, there were 1,788 incident cases of STDR and 103 incident cases of PDR.
Study limitations included the use of annual screening data to simulate biennial screening, Owen and team noted. “These findings may give an over-optimistic indication of compliance, as implementing biennial screening may worsen adherence to an extended screening regimen.”
“However, these findings using real-world data reflect clinical practice,” they added. “A randomized controlled clinical trial would be the gold standard of assessing the impact of biennial screening, but such a study would need to be large to compare impact across different age and ethnic groups.”
The study was funded by the Wellcome Trust, the NHS Transformation Directorate, and the Health Foundation.
Owen and Gregori have no disclosures. Some study co-authors reported relationships with industry.
British Journal of Ophthalmology
Source Reference: Olvera-Barrios A, et al “Two-year recall for people with no diabetic retinopathy: a multi-ethnic population-based retrospective cohort study using real-world data to quantify the effect” Br J Ophthalmol 2023; DOI: 10.1136/bjo-2023-324097.