Toronto tele-retinal screening program for detection of diabetic retinopathy and macular edema

Implementation of Artificial Intelligence-Based Diabetic Retinopathy Screening in a Tertiary Care Hospital in Quebec: Prospective Validation Study

BACKGROUND

Diabetic retinopathy (DR) affects about 25% of people with diabetes in Canada. Early detection of DR is essential for preventing vision loss.

OBJECTIVE

We evaluated the real-world performance of an artificial intelligence (AI) system that analyzes fundus images for DR screening in a Quebec tertiary care center.

METHODS

We prospectively recruited adult patients with diabetes at the Centre hospitalier de l'Université de Montréal (CHUM) in Montreal, Quebec, Canada. Patients underwent dual-pathway screening: first by the Computer Assisted Retinal Analysis (CARA) AI system (index test), then by standard ophthalmological examination (reference standard). We measured the AI system's sensitivity and specificity for detecting referable disease at the patient level, along with its performance for detecting any retinopathy and diabetic macular edema (DME) at the eye level, and potential cost savings.

RESULTS

This study included 115 patients. CARA demonstrated a sensitivity of 87.5% (95% CI 71.9-95.0) and specificity of 66.2% (95% CI 54.3-76.3) for detecting referable disease at the patient level. For any retinopathy detection at the eye level, CARA showed 88.2% sensitivity (95% CI 76.6-94.5) and 71.4% specificity (95% CI 63.7-78.1). For DME detection, CARA had 100% sensitivity (95% CI 64.6-100) and 81.9% specificity (95% CI 75.6-86.8). Potential yearly savings from implementing CARA at the CHUM were estimated at CAD $245,635 (US $177,643.23, as of July 26, 2024) considering 5000 patients with diabetes.

CONCLUSIONS

Our study indicates that integrating a semiautomated AI system for DR screening demonstrates high sensitivity for detecting referable disease in a real-world setting. This system has the potential to improve screening efficiency and reduce costs at the CHUM, but more work is needed to validate it.

Follow-up in a point-of-care diabetic retinopathy program in Pittsburgh: a non-concurrent retrospective cohort study

BACKGROUND

The Point-of-Care Diabetic Retinopathy Examination Program (POCDREP) was initiated in 2015 at the University of Pittsburgh/UPMC in response to low diabetic retinopathy (DR) examination rates, a condition affecting a quarter of people with diabetes mellitus (PwDM) and leading to blindness. Early detection and treatment are critical with DR prevalence projected to triple by 2050. Approximately, half of PwDM in the U.S. undergo yearly examinations, and there are reported varying follow-up rates with eye care professionals, with limited data on the factors influencing these trends. POCDREP aimed to address screening and follow-up gap, partnering with diverse healthcare entities, including primary care sites, free clinics, and federally qualified health centers.

METHODS

A non-concurrent retrospective cohort study spanning 2015-2018 examined data using electronic health records of patients who underwent retinal imaging. Imaging was performed using 31 cameras across various settings, with results interpreted by ophthalmologists. Follow-up recommendations were made for cases with vision-threatening DR (VTDR), incidental findings, or indeterminate results. Factors influencing follow-up were analyzed, including demographic, clinical, and imaging-related variables. We assessed the findings at follow-up of patients with indeterminate results.

RESULTS

Out of 7,733 examinations (6,242 patients), 32.25% were recommended for follow-up. Among these, 5.57% were classified as having VTDR, 14.34% had other ocular findings such as suspected glaucoma and age-related macular degeneration (AMD), and 12.13% were indeterminate. Of those recommended for follow-up, only 30.87% were assessed by eye care within six months. Older age, marriage, and severe DR were associated with higher odds of following up. Almost two thirds (64.35%) of the patients with indeterminate exams were found with a vision-threatening disease at follow-up.

CONCLUSION

The six-month follow-up rate was found to be suboptimal. Influential factors for follow-up included age, marital status, and the severity of diabetic retinopathy (DR). While the program successfully identified a range of ocular conditions, screening initiatives must extend beyond mere disease detection. Ensuring patient follow-up is crucial to DR preventing programs mission. Recommended strategies to improve follow-up adherence include education, incentives, and personalized interventions. Additional research is necessary to pinpoint modifiable factors that impact adherence and to develop targeted interventions.

Diabetic retinopathy screening integrated in a multidisciplinary diabetes care clinic: a pilot project

OBJECTIVE

To characterize patients referred for diabetic retinopathy (DR) screening in a unique multidisciplinary diabetes care clinic at a tertiary care centre.

METHODS

A retrospective study was conducted involving patients who were referred to the Cardiac and Renal Endocrine Clinic at a tertiary care centre (University Health Network) for DR screening between April 2019-March 2020 and November 2020-August 2021. Patients' demographics; micro- and macrovascular disease measurements; visual acuity, intraocular pressure, fundus imaging, and optical coherence tomography results were collected and analyzed.

RESULTS

Of the 64 patients who attended the clinic, 21 patients (33%) with type 2 diabetes had on-site DR screening. The remaining 43 patients had DR screening within 6 months of the appointment or were under ophthalmology care with annual screening visits elsewhere. Of the 21 patients who underwent retinopathy screening, 7 patients (33%) had DR: 4 had mild nonproliferative DR, 2 had moderate nonproliferative DR, 1 had proliferative DR, and 1 had macular edema. Patients with DR had a significantly longer diabetes duration than patients without DR (24.5 ± 10.2 years vs 12.5 ± 5.8 years; p = 0.0247). No significant differences were observed in glycemic control, blood pressure, lipid profiles, kidney function, visual acuity, or intraocular pressure.

CONCLUSIONS

Our analysis suggests a potential benefit of integrated DR screening in patients with long-standing diabetes as part of a multidisciplinary diabetes care clinic to diagnose and manage DR. Future work is needed to further develop such clinics and investigate their long-term effect on patient outcomes.

Prevalence of self-reported visual impairment among people in Canada with and without diabetes: findings from population-based surveys from 1994 to 2014

BACKGROUND

Diabetes, a leading cause of visual impairment, is on the rise in Canada. We assessed trends in the prevalence of visual impairment among people in Canada with and without diabetes to inform the development of strategies and policies for the management of visual impairment.

METHODS

We analyzed self-reported data from respondents aged 45 years and older in 7 cycles of nationwide surveys (National Population Health Survey and Canadian Community Health Survey) from 1994/95 to 2013/14. The age- and sex-standardized prevalence of visual impairment was calculated. We assessed comparisons by levels of education and income, using sex-standardized prevalence owing to sparse data.

RESULTS

Among people in Canada with diabetes, the age- and sex-standardized prevalence of visual impairment was 7.37% (95% confidence interval [CI] 5.31%-9.43%) in 1994/95 and 1996/97 combined, decreasing to 3.03% (95% CI 2.48%-3.57%) in 2013/14, giving a standardized prevalence ratio of 0.41 (95% CI 0.30-0.56) comparing 2013/14 with 1994/95 and 1996/97 combined. Among people in Canada without diabetes, visual impairment prevalence decreased from 3.72% (95% CI 3.31%-4.14%) in 1994/95 and 1996/97 combined to 1.69% (95% CI 1.52%-1.87%) in 2013/14, with a standardized prevalence ratio of 0.45 (95% CI 0.40-0.52). Decreased sex-standardized prevalence of visual impairment was observed among people with high and low education levels and incomes among those with and without diabetes.

INTERPRETATION

Visual impairment prevalence was roughly 2 times higher among those with versus without diabetes in all survey years; from 1994 to 2014, visual impairment prevalence decreased among those with and without diabetes irrespective of education and income levels. These results suggest effective collective efforts by clinicians, researchers, the public and government.

Assessing the feasibility, acceptability, and fidelity of a tele-retinopathy-based intervention to encourage greater attendance to diabetic retinopathy screening in immigrants living with diabetes from China and African-Caribbean countries in Ottawa, Canada: a protocol

BACKGROUND

Diabetic retinopathy is a leading cause of preventable blindness in Canada. Clinical guidelines recommend annual diabetic retinopathy screening for people living with diabetes to reduce the risk and progression of vision loss. However, many Canadians with diabetes do not attend screening. Screening rates are even lower in immigrants to Canada including people from China, Africa, and the Caribbean, and these groups are also at higher risk of developing diabetes complications. We aim to assess the feasibility, acceptability, and fidelity of a co-developed, linguistically and culturally tailored tele-retinopathy screening intervention for Mandarin-speaking immigrants from China and French-speaking immigrants from African-Caribbean countries living with diabetes in Ottawa, Canada, and identify how many from each population group attend screening during the pilot period.

METHODS

We will work with our health system and patient partners to conduct a 6-month feasibility pilot of a tele-retinopathy screening intervention in a Community Health Centre in Ottawa. We anticipate recruiting 50-150 patients and 5-10 health care providers involved in delivering the intervention for the pilot. Acceptability will be assessed via a Theoretical Framework of Acceptability-informed survey with patients and health care providers. To assess feasibility, we will use a Theoretical Domains Framework-informed interview guide and to assess fidelity, and we will use a survey informed by the National Institutes of Health framework from the perspective of health care providers. We will also collect patient demographics (i.e., age, gender, ethnicity, health insurance status, and immigration information), screening outcomes (i.e., patients with retinopathy identified, patients requiring specialist care), patient costs, and other intervention-related variables such as preferred language. Survey data will be descriptively analyzed and qualitative data will undergo content analysis.

DISCUSSION

This feasibility pilot study will capture how many people living with diabetes from each group attend the diabetic retinopathy screening, costs, and implementation processes for the tele-retinopathy screening intervention. The study will indicate the practicability and suitability of the intervention in increasing screening attendance in the target population groups. The study results will inform a patient-randomized trial, provide evidence to conduct an economic evaluation of the intervention, and optimize the community-based intervention.

Prevalence and predictors for being unscreened for diabetic retinopathy: a population-based study over a decade

OBJECTIVE

To determine the population-level predictors for being unscreened for diabetic retinopathy (DR) among individuals with diabetes in a developed country.

DESIGN

A retrospective population-based repeated-cross-sectional study.

PARTICIPANTS

All individuals with diabetes (types 1 and 2) aged ≥20 years in the universal health care system in Ontario were identified in the 2011-2013 and 2017-2019 time periods.

METHODS

The Mantel-Haenszel test was used for the relative risk (RR) comparison of subcategories stratified by the 2 cross-sectional time periods.

RESULTS

A total of 1 145 645 and 1 346 578 individuals with diabetes were identified in 2011-2013 and 2017-2019, respectively. The proportion of patients unscreened for DR declined very slightly from 35% (n = 405 967) in 2011-2013 to 34% (n = 455 027) in 2017-2019 of the population with diabetes (RR = 0.967; 95% CI, 0.964-0.9693; p < 0.0001). Young adults aged 20-39 years of age had the highest proportion of unscreened patients (62% and 58% in 2011-2013 and 2017-2019, respectively). Additionally, those who had a lower income quintile (RR = 1.039; 95% CI, 1.036-1.044; p < 0.0001), were recent immigrants (RR = 1.286; 95% CI, 1.280-1.293; p < 0.0001), lived in urban areas (RR = 1.149; 95% CI, 1.145-1.154; p < 0.0001), had a mental health history (RR = 1.117; 95% CI, 1.112-1.122; p < 0.0001), or lacked a connection to a primary care provider (RR = 1.656; 95% CI, 1.644-1.668; p < 0.0001) had a higher risk of being unscreened.

CONCLUSIONS

This population-based study suggests that over 1 decade, 33% of individuals with diabetes are unscreened for DR, and young age, low income, immigration, residing in a large city, mental health illness, and no primary care access are the main predictors.

EVALUATION OF THE INCLUSION OF SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY IN A TELEMEDICINE DIABETIC RETINOPATHY SCREENING PROGRAM: A Real Clinical Practice

PURPOSE

To evaluate whether combining spectral domain optical coherence tomography with monoscopic fundus photography using a nonmydriatic camera (MFP-NMC) improves the accuracy of diabetic macular edema (DME) referrals in a teleophthalmology diabetic retinopathy screening program.

METHODS

We conducted a cross-sectional study with all diabetic patients aged 18 years or older who attended screening from September 2016 to December 2017. We assessed DME according to the three MFP-NMC and the four spectral domain optical coherence tomography criteria. The sensitivity and specificity obtained for each criterion were estimated by comparing them with the ground truth of DME.

RESULTS

This study included 3,918 eyes (1,925 patients; median age, 66 years; interquartile range, 58-73; females, 40.7%; once-screened, 68.1%). The prevalence of DME ranged from 1.22% to 1.83% and 1.54% to 8.77% on MFP-NMC and spectral domain optical coherence tomography, respectively. Sensitivity barely reached 50% in MFP-NMC and less for the quantitative criteria of spectral domain optical coherence tomography. When macular thickening and anatomical signs of DME were considered, sensitivity increased to 88.3% and the false DMEs and non-gradable images were reduced.

CONCLUSION

Macular thickening and anatomical signs showed the highest suitability for screening, with a sensitivity of 88.3% and a specificity of 99.8%. Notably, MFP-NMC alone missed half of the true DMEs that lacked indirect signs.

Examining the Role of Telemedicine in Diabetic Retinopathy

With the increasing prevalence of diabetic retinopathy (DR), screening is of the utmost importance to prevent vision loss for patients and reduce financial costs for the healthcare system. Unfortunately, it appears that the capacity of optometrists and ophthalmologists to adequately perform in-person screenings of DR will be insufficient within the coming years. Telemedicine offers the opportunity to expand access to screening while reducing the economic and temporal burden associated with current in-person protocols. The present literature review summarizes the latest developments in telemedicine for DR screening, considerations for stakeholders, barriers to implementation, and future directions in this area. As the role of telemedicine in DR screening continues to expand, further work will be necessary to continually optimize practices and improve long-term patient outcomes.

Mailed Letter Versus Phone Call to Increase Diabetic-Related Retinopathy Screening Engagement by Patients in a Team-Based Primary Care Practice: Prospective, Single-Masked, Randomized Trial

BACKGROUND

Vision loss from diabetic-related retinopathy (DR) is preventable through regular screening.

OBJECTIVE

The purpose of this study was to test different patient engagement approaches to expand a teleophthalmology program at a primary care clinic in the city of Toronto, Canada.

METHODS

A teleophthalmology program was set up in a large, urban, academic, team-based primary care practice. Patients older than 18 years with type 1 or type 2 diabetes were randomized to one of the following 4 engagement strategies: phone call, mail, mail plus phone call, or usual care. Outreach was conducted by administrative staff within the clinic. The primary outcome was booking an appointment for DR screening.

RESULTS

A total of 23 patients in the phone, 28 in the mail, 32 in the mail plus phone call, and 27 in the control (usual care) group were included in the analysis. After the intervention and after excluding patients who said they were screened, 88% (15/17) of patients in the phone, 11% (2/18) in the mail, and 100% (21/21) in the mail and phone group booked an appointment with the teleophthalmology program compared to 0% (0/12) in the control group. Phoning patients positively predicted patients booking a teleophthalmology appointment (P<.001), whereas mailing a letter had no effect.

CONCLUSIONS

Patient engagement to book DR screening via teleophthalmology in an urban, academic, team-based primary care practice using telephone calls was much more effective than patient engagement using letters or usual care. Practices that have access to a local DR screening program and have resources for such engagement strategies should consider using them as a means to improve their DR screening rates.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03927859; https://clinicaltrials.gov/ct2/show/NCT03927859.

Perceptions of a Teleophthalmology Screening Program for Diabetic Retinopathy in Adults With Type 1 and Type 2 Diabetes in Urban Primary Care Settings

OBJECTIVES

Teleophthalmology has improved diabetic retinopathy screening, and should be expanded in urban areas, where most unscreened individuals reside. In this study we explored facilitators and barriers of teleophthalmology in primary care settings in Toronto, Canada.

METHODS

Semistructured interviews were conducted with 7 health-care providers and 7 individuals with diabetes to explore their perspectives of teleophthalmology in urban primary care settings. Interview data were analyzed using interpretive thematic analysis to generate themes.

RESULTS

Six themes were identified. Facilitators included patient-centred implementation, access to teleophthalmology at primary care sites and patients' trust in their providers' recommendations. Barriers included patients' lack of understanding of diabetic retinopathy and the health-care system, providers' lack of interest and the need to streamline administrative processes.

CONCLUSIONS

Although teleophthalmology was well-received by patients, there was limited interest from primary care providers. Strategies for increasing uptake include increasing primary care providers' awareness of teleophthalmology's value in urban centres, improving administrative processes and centralizing patient recruitment.

Diagnostic accuracy of teleretinal screening for detection of diabetic retinopathy and age-related macular degeneration: a systematic review and meta-analysis

Objective

To evaluate the diagnostic accuracy of teleretinal screening compared with face-to-face examination for detection of diabetic retinopathy (DR) and age-related macular degeneration (AMD).

Methods and analysis

This study adhered to the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA). A comprehensive search of OVID MEDLINE, EMBASE and Cochrane CENTRAL was performed from January 2010 to July 2021. QUADAS-2 tool was used to assess methodological quality and applicability of the studies. A bivariate random effects model was used to perform the meta-analysis. Referrable DR was defined as any disease severity equal to or worse than moderate non-proliferative DR or diabetic macular oedema (DMO).

Results

28 articles were included. Teleretinal screening achieved a sensitivity of 0.91 (95% CI: 0.82 to 0.96) and specificity of 0.88 (0.74 to 0.95) for any DR (13 studies, n=7207, Grading of Recommendations, Assessment, Development and Evaluation (GRADE) low). Accuracy for referrable DR (10 studies, n=6373, GRADE moderate) was lower with a sensitivity of 0.88 (0.81 to 0.93) and specificity of 0.86 (0.79 to 0.90). After exclusion of ungradable images, the specificity for referrable DR increased to 0.95 (0.90 to 0.98), while the sensitivity remained nearly unchanged at 0.85 (0.76 to 0.91). Teleretinal screening achieved a sensitivity of 0.71 (0.49 to 0.86) and specificity of 0.88 (0.85 to 0.90) for detection of AMD (three studies, n=697, GRADE low).

Conclusion

Teleretinal screening is highly accurate for detecting any DR and DR warranting referral. Data for AMD screening is promising but warrants further investigation.

PROSPERO registration number

CRD42020191994.

Evidence-based Canadian guidelines for tele-retina screening for diabetic retinopathy: recommendations from the Canadian Retina Research Network (CR2N) Tele-Retina Steering Committee

OBJECTIVE

The purpose of this report is to develop a consensus for Canadian national guidelines specific to a tele-medicine approach to screening for diabetic retinopathy (DR) using evidence-based and clinical data.

METHODS

Canadian Tele-Screening Grading Scales for DR and diabetic macular edema (DME) were created primarily based on severity grading scales outlined by the International Clinical Diabetic Retinopathy Disease Severity Scale (ICDR) and the Scottish DR Grading Scheme 2007. Other grading scales used in international screening programs and the clinical expertise of the Canadian Retina Research Network members and retina specialists nationwide were also used in the creation of the guidelines.

RESULTS

National Tele-Screening Guidelines for DR and DME with and without optical coherence tomography (OCT) images are proposed. These outline a diagnosis and management algorithm for patients presenting with different stages of DR and/or DME. General guidelines detailing the requirements for imaged retina fields, image quality, quality control, and follow-up care and the role of visual acuity, pupil dilation, OCT, ultra-wide-field imaging, and artificial intelligence are discussed.

CONCLUSIONS

Tele-retina screening can help to address the need for timely and effective screening for DR, whose prevalence continues to rise. A standardized and evidence-based national approach to DR tele-screening has been proposed, based on DR/DME grading using two 45° image fields or a single widefield or ultra-wide-field image, preferable use of OCT imaging, and a focus on local quality control measures.

Sociodemographics Associated With Risk of Diabetic Retinopathy Detected by Tele-Ophthalmology: 5-Year Results of the Toronto Tele-Retinal Screening Program

OBJECTIVES

Our aim in this study was to describe screening outcomes and sociodemographic characteristics of patients in an urban tele-ophthalmology screening program for diabetic retinopathy (DR).

METHODS

A prospective cohort study was conducted on adults with diabetes type 1 or type 2 enrolled in the Toronto Tele-Retinal Screening Program between September 2013 and March 2019.

RESULTS

A total of 1,374 screenings were completed, of which 344 (25%) detected DR. Of all participants, 17% did not have provincial health coverage and 21% never had an eye exam. Of the 587 patients who completed sociodemographic questionnaires, the majority (84%) were born outside of Canada, and only 62% preferred English as their spoken language. Forty percent reported a household income of <$25,000, with these participants having an increased likelihood of detectable DR (odds ratio [OR], 1.83; p<0.01).

CONCLUSIONS

Participants with low income are more likely to screen positive for DR. Tele-ophthalmologic screening can be effective in an urban, culturally diverse and socioeconomically disadvantaged population.

Barriers to and enablers of attendance at diabetic retinopathy screening experienced by immigrants to Canada from multiple cultural and linguistic minority groups

AIM

To identify barriers to/enablers of attendance at eye screening among three groups of immigrantsto Canada from cultural/linguistic minority groups living with diabetes.

METHODS

Using a patient-oriented research approach leveraging Diabetes Action Canada's patient engagement platform, we interviewed a purposeful sample of people with type 2 diabetes who had immigrated to Canada from: Pakistan (interviews in Urdu), China (interviews in Mandarin) and French-speaking African and Caribbean nations (interviews in French). We collected and analysed data based on the Theoretical Domains Framework covering key modifiable factors that may operate as barriers to or enablers of attending eye screening. We used directed content analysis to code barrier/enabler domains. Barriers/enablers were mapped to behaviour change techniques to inform future intervention development.

RESULTS

We interviewed 39 people (13 per group). Many barriers/enablers were consistent across groups, including views about harms caused by screening itself, practical appointment issues including forgetting, screening costs, wait times and making/getting to an appointment, lack of awareness about retinopathy screening, language barriers, and family and clinical support. Group-specific barriers/enablers included a preference to return to one's country of birth for screening, the impact of winter, and preferences for alternative medicine.

CONCLUSION

Our results can inform linguistic and culturally competent interventions to support immigrants living with diabetes in attending eye screening to prevent avoidable blindness.

Impact of Intersecting Systems of Oppression on Diabetic Retinopathy Screening Among Those Who Identify as Women of Low Socioeconomic Status: Protocol for a Convergent Mixed Methods Study

Background

By 2025, 5 million Canadians will be diagnosed with diabetes, and women from lower socioeconomic groups will likely account for most new diagnoses. Diabetic retinopathy is a primary vision complication of diabetes and a leading cause of blindness among adults, with 26% prevalence among women. Tele-retina is a branch of telemedicine that delivers eye care remotely. Screening for diabetic retinopathy has great potential to reduce the incidence of blindness, yet there is an adverse association among screening, income, and gender.

Objective

We aim to explore gender disparity in the provision of tele-retina program services for diabetic retinopathy screening in a cohort of women of low socioeconomic status (SES) receiving services in South Riverdale Community Health Centre (SRCHC) between 2014 and 2019.

Methods

Using a convergent mixed methods design, we want to understand patients’, providers’, administrators’, and decision makers’ perceptions of the facilitators and barriers associated with the implementation and adoption of tele-retina. Multivariate logistic regression will be utilized to assess the association among client characteristics, referral source, and diabetic retinopathy screening. Guided by a grounded theory approach, systematic coding of data and thematic analysis will be utilized to identify key facilitators and barriers to the implementation and adoption of tele-retina.

Results

For the quantitative component, we anticipate a cohort of 2500 patients, and we expect to collect data on the overall patterns of tele-retina program use, including descriptions of program utilization rates (such as data on received and completed diabetic retinopathy screening referrals) along the landscape of patient populations receiving these services. For the qualitative component, we plan to interview up to 21 patients and 14 providers, administrators, and decision makers, and to conduct up to 14 hours of observations alongside review of relevant documents. The interview guide is being developed in collaboration with our patient partners. Through the use of mixed methods research, the inquiry will be approached from different perspectives. Mixed methods will guide us in combining the rich subjective insights on complex realities from qualitative inquiry with the standard generalizable data that will be generated through quantitative research. The study is under review by the University Health Network Research Ethics Board (19-5628). We expect to begin recruitment in winter 2021.

Conclusions

In Ontario, the screening rate for diabetic retinopathy among low income groups remains below 65%. Understanding the facilitators and barriers to diabetic retinopathy screening may be a prerequisite in the development of a successful screening program. This study is the first Ontario study to focus on diabetic retinopathy screening practices in women of low SES, with the aim to improve their health outcomes and revolutionize access to quality care.

International Registered Report Identifier (IRRID)

PRR1-10.2196/23492

Diabetic Retinopathy Screening: A Systematic Review of Qualitative Literature

OBJECTIVES

Diabetic retinopathy is a common microvascular complication that leads to vision loss. Despite national and international organizations developing guidelines for diabetic retinopathy screening, patients with diabetes remain unscreened. Our aim was to understand facilitators and barriers influencing diabetic retinopathy screening attendance and to examine factors that promote program success.

METHODS

MEDLINE, Embase, PsycINFO and CINAHL from inception until September 23, 2019 were used for data collection. Studies were included if they were original qualitative research articles, included adults >18 years of age and assessed diabetic retinopathy screening programs or retinopathy screening as a component of a general diabetes care program. A "best-fit" framework synthesis methodology was used for this analysis.

RESULTS

Twenty-nine articles involving 1,433 participants were identified. Six themes of barriers to, and facilitators of, diabetic retinopathy screening were identified, including access to screening, knowledge and information sharing, training and skills competency, service delivery, cultural competency and psychological factors. Cost and competing interests were common barriers to access; lack of knowledge about screening services was also a frequently reported barrier. Both patients and providers identified the need for improved service delivery, especially the referral and follow-up process. Providers recognized the need for additional training, patients enumerated several psychological barriers to screening uptake and cultural considerations were believed to be important, particularly among indigenous communities.

CONCLUSIONS

To improve screening uptake, the identified challenges must be addressed while also reinforcing the facilitators. Furthermore, program administrators could model new and unsuccessful screening programs after the successful ones while also considering local peculiarities.

Tele-retina screening of diabetic retinopathy among at-risk populations: an economic analysis

OBJECTIVES

To assess the cost-effectiveness of the pilot Toronto tele-retina screening program in comparison with existing standard of care (SOC) diabetic retinopathy (DR) screening for patients with diabetes mellitus and in a simulated Pan-Ontarian cohort.

METHODS

Decision trees were constructed to compare tele-retina to SOC in the pilot and Pan-Ontarian cohort. Cost-effectiveness was assessed as cost per case detected (true-positive) and cost per case correctly diagnosed (true-positive and true-negative results).

RESULTS

Pilot program screening costs were $95.77 and $137.56 for tele-retina and SOC, respectively. In the base-case analysis, cost per case correctly detected was $379.06 with tele-retina and $985.56 with SOC, and the cost per case correctly diagnosed was $109.29 and $315.22, respectively. In the sensitivity analysis, cost per case correctly detected was $467.29 with tele-retina and $894.93 with SOC, and the cost per case correctly diagnosed was $136.88 and $250.35, respectively. Pan-Ontarian screening costs were $57.58 and $137.56 for tele-retina and SOC, respectively. The cost per case correctly detected was $281.10 with tele-retina and $982.00 with SOC, and the cost per case correctly diagnosed was $82.21 and $314.14, respectively. For both pilot and Pan-Ontarian sensitivity analyses, tele-retina remained the dominant strategy (ICER <0).

CONCLUSIONS

Findings from this study suggest that tele-retina is a more cost-effective means of screening for diabetic retinopathy than the SOC in urban and rural underscreened communities. Subsequent economic studies should focus on evaluations that consider the impact of tele-retina on the prevention of severe vision loss in underscreened urban and rural communities.