National Diabetic Retinopathy Screening Programme Research Articles

AI telemedicine screening in ophthalmology: health economic considerations

AI telemedicine screening in ophthalmology: health economic considerations

Long-term trends in incidence and prevalence of severe sight impairment due to diabetes in South East Scotland before and after implementation of diabetic retinopathy screening

The study set out to examine the impact of the introduction of a national diabetic retinopathy screening programme in Scotland in 2006 on incidence and trends in severe sight impairment (SSI) certification due to diabetes over three decades. We analysed SSI certification due to diabetic eye disease in Fife, Scotland, between 2010 and 2019 and compared it to previously published estimates from 1990 onwards. Population estimates of the general population and those with diabetes were obtained from the National Records of Scotland and the National Diabetes Register, NHS SCI Diabetes, respectively. Mean annual incidence of SSI in the population with diabetes, 1990–2019, before and after the introduction of diabetic retinopathy screening was compared using a Mann–Whitney U Test. Mean incidence in 2007–2019 was 19.8/100,000 and was significantly less than the period before the systematic screening, 1990–2006 (57.5/100,000, p < .001). Mean SSI incidence due to diabetes in Fife between 2010 and 2019 was significantly lower than in the previous decades ( p < .001) at 16.4 per 100,000 for the population with diabetes, per year ( SD 10.0; 95% confidence interval: [9.2, 23.5]) compared to 42.7 per 100,000 in 2000–2009 and 64.3 per 100,000 in 1990–1999. This study demonstrates a significant reduction in the annual incidence of SSI due to diabetes before and after the introduction of the screening programme provides evidence for the benefit of systematic diabetic retinopathy screening programmes. Other factors including improved management of diabetes and risk factors will have also had an impact emphasizing the importance of a multidisciplinary approach to the prevention of sight loss in diabetes.

Real-time diabetic retinopathy screening by deep learning in a multisite national screening programme: a prospective interventional cohort study

Diabetic retinopathy is a leading cause of preventable blindness, especially in low-income and middle-income countries (LMICs). Deep-learning systems have the potential to enhance diabetic retinopathy screenings in these settings, yet prospective studies assessing their usability and performance are scarce. We did a prospective interventional cohort study to evaluate the real-world performance and feasibility of deploying a deep-learning system into the health-care system of Thailand. Patients with diabetes and listed on the national diabetes registry, aged 18 years or older, able to have their fundus photograph taken for at least one eye, and due for screening as per the Thai Ministry of Public Health guidelines were eligible for inclusion. Eligible patients were screened with the deep-learning system at nine primary care sites under Thailand's national diabetic retinopathy screening programme. Patients with a previous diagnosis of diabetic macular oedema, severe non-proliferative diabetic retinopathy, or proliferative diabetic retinopathy; previous laser treatment of the retina or retinal surgery; other non-diabetic retinopathy eye disease requiring referral to an ophthalmologist; or inability to have fundus photograph taken of both eyes for any reason were excluded. Deep-learning system-based interpretations of patient fundus images and referral recommendations were provided in real time. As a safety mechanism, regional retina specialists over-read each image. Performance of the deep-learning system (accuracy, sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]) were measured against an adjudicated reference standard, provided by fellowship-trained retina specialists. This study is registered with the Thai national clinical trials registry, TCRT20190902002. Between Dec 12, 2018, and March 29, 2020, 7940 patients were screened for inclusion. 7651 (96·3%) patients were eligible for study analysis, and 2412 (31·5%) patients were referred for diabetic retinopathy, diabetic macular oedema, ungradable images, or low visual acuity. For vision-threatening diabetic retinopathy, the deep-learning system had an accuracy of 94·7% (95% CI 93·0-96·2), sensitivity of 91·4% (87·1-95·0), and specificity of 95·4% (94·1-96·7). The retina specialist over-readers had an accuracy of 93·5 (91·7-95·0; p=0·17), a sensitivity of 84·8% (79·4-90·0; p=0·024), and specificity of 95·5% (94·1-96·7; p=0·98). The PPV for the deep-learning system was 79·2 (95% CI 73·8-84·3) compared with 75·6 (69·8-81·1) for the over-readers. The NPV for the deep-learning system was 95·5 (92·8-97·9) compared with 92·4 (89·3-95·5) for the over-readers. A deep-learning system can deliver real-time diabetic retinopathy detection capability similar to retina specialists in community-based screening settings. Socioenvironmental factors and workflows must be taken into consideration when implementing a deep-learning system within a large-scale screening programme in LMICs. Google and Rajavithi Hospital, Bangkok, Thailand. For the Thai translation of the abstract see Supplementary Materials section.

Good perception of own lifestyle associated with poor attendance at Diabetic RetinaScreen Programme

Abstract Background Untreated diabetic retinopathy is the most common cause of sight loss in people of working age. The Diabetic RetinaScreen programme (DRS) is the national diabetic retinopathy screening programme in Ireland which commenced in 2013 with aim to prevent diabetic retinopathy and subsequent blindness, through free screening and ophthalmology services. High uptake is crucial for the effectiveness of the programme. This study aimed to determine the sociodemographic, lifestyle and healthcare factors associated with attendance at the DRS programme in Ireland, using data from a national cohort study, the Irish Longitudinal Study on Ageing (TILDA). Methods The TILDA wave-4 dataset (anonymised) was utilised for the current study. Questions on DRS invitation and attendance formed part of the wave 4 study questionnaire. Multivariate logistic regression was used to examine independent factors associated with attendance. SPSS was used for analysis. Results 418 respondents (7.3%) were invited to DRS and 373 (89.2%) attended. Among all those who were invited to DRS, 244 (58.4%) were male and 174 (41.6%) were female. The mean age was 69.8 years (53-84 years). Following multivariate logistic regression, following a good diet/taking exercise (OR = 0.29, 95% CI 0.10-0.82) was negatively associated with attendance, after adjustment for age, male gender, higher education and medical card. Conclusions Recognising factors linked with uptake is important to develop goal directed strategies. Interestingly those who stated they followed a good diet & took exercise and were compliant with DM prevention were less likely to attend DRS. Previous research has also indicated that a higher physical activity level is associated with higher self-perceived health status Key messages Persons with DM with good compliance to diet and exercise were found to have poor attendance at the DRS programme. Targeted advertising is required to raise awareness of diabetic retinopathy.

Factors associated with non-attendance in the Irish national diabetic retinopathy screening programme (INDEAR study report no. 2)

AimsWe aimed to determine the patient and screening-level factors that are associated with non-attendance in the Irish National Diabetic Retinal screening programme (Diabetic RetinaScreen). To accomplish this, we modelled a selection of predictors derived from the historical screening records of patients with diabetes.MethodsIn this cohort study, appointment data from the national diabetic retinopathy screening programme (RetinaScreen) were extracted and augmented using publicly available meteorological and geospatial data. A total of 653,969 appointments from 158,655 patients were included for analysis. Mixed-effects models (univariable and multivariable) were used to estimate the influence of several variables on non-attendance to screening appointments.ResultsAll variables considered for analysis were statistically significant. Variables of note, with meaningful effect, were age (OR: 1.23 per decade away from 70; 95% CI: [1.22–1.24]), type 2 diabetes (OR: 1.10; 95% CI: [1.06–1.14]) and socio-economic deprivation (OR: 1.12; 95% CI: [1.09–1.16]). A majority (52%) of missed appointments were from patients who had missed three or more appointments.ConclusionsThis study is the first to outline factors that are associated with non-attendance within the Irish national diabetic retinopathy screening service. In particular, when corrected for age and other factors, patients with type 2 diabetes had higher rates of non-attendance. Additionally, this is the first study of any diabetic screening programme to demonstrate that weather may influence attendance. This research provides unique insight to guide the implementation of an optimal and cost-effective intervention strategy to improve attendance.

Artificial intelligence for teleophthalmology-based diabetic retinopathy screening in a national programme: an economic analysis modelling study

Deep learning is a novel machine learning technique that has been shown to be as effective as human graders in detecting diabetic retinopathy from fundus photographs. We used a cost-minimisation analysis to evaluate the potential savings of two deep learning approaches as compared with the current human assessment: a semi-automated deep learning model as a triage filter before secondary human assessment; and a fully automated deep learning model without human assessment. In this economic analysis modelling study, using 39 006 consecutive patients with diabetes in a national diabetic retinopathy screening programme in Singapore in 2015, we used a decision tree model and TreeAge Pro to compare the actual cost of screening this cohort with human graders against the simulated cost for semi-automated and fully automated screening models. Model parameters included diabetic retinopathy prevalence rates, diabetic retinopathy screening costs under each screening model, cost of medical consultation, and diagnostic performance (ie, sensitivity and specificity). The primary outcome was total cost for each screening model. Deterministic sensitivity analyses were done to gauge the sensitivity of the results to key model assumptions. From the health system perspective, the semi-automated screening model was the least expensive of the three models, at US$62 per patient per year. The fully automated model was $66 per patient per year, and the human assessment model was $77 per patient per year. The savings to the Singapore health system associated with switching to the semi-automated model are estimated to be $489 000, which is roughly 20% of the current annual screening cost. By 2050, Singapore is projected to have 1 million people with diabetes; at this time, the estimated annual savings would be $15 million. This study provides a strong economic rationale for using deep learning systems as an assistive tool to screen for diabetic retinopathy. Ministry of Health, Singapore.

Towards developing a programme theory for the uptake of a national retinopathy screening programme in Ireland: a realist evaluation

Introduction: In 2013, the national diabetic retinopathy screening programme (NDRSP) was introduced in Ireland to offer free, regular retinopathy screening to people with diabetes. Ensuring a high uptake of a national retinopathy screening programme is challenging [1]. Non-attendance for screening has been identified as a risk factor for poor visual outcomes among those with diabetes [2]. Suboptimal uptake has been previously highlighted by regional screening programmes in Ireland, with attendance rates ranging from 49-80% [3-5]. Therefore, it is essential and timely to understand factors that facilitate or deter screening attendance as the NDRSP is implemented. The aim of this study was to identify and explain why the NDRSP was working (or not working), for whom and in what circumstances to produce outcomes. Methods: This study was guided by a realist evaluation framework and adopts a multi-stage mixed methods design. Qualitative data from documents and semi-structured interviews with a purposive sample of national stakeholders (n=19) were used to develop the initial programme theories. These theories were tested in two large primary health centre in Ireland. Quantitative data extracted the medical records of all adults aged ≥18 years with diabetes registered with the practices were collected to establish uptake rates. A qualitative component was conducted using semi-structured interviews. Sampling was based on four outcome groups identified during the quantitative component of the study: consenting, attending, non-attending, not consenting. Framework analysis was used to identify factors that influenced the decision to participate in the NDRSP. Results: Against the back drop of a variation in existing retinopathy screening services, it was expected that members of the target population would decide to attend the NDRSP and a national uptake of 80% would be achieved. A total of 581 people with diabetes were included in the quantitative analysis. Over a 14 month period, the uptake of the screening programme was 63%. Qualitative analysis suggested that a fear of blindness and a belief that retinopathy screening could reduce the risk of diabetes-related blindness enabled screening attendance. Having had a recent eye examination at another screening provider was a common reason for not attending the NDRSP. No relative advantage of attending the NDRSP over exiting screening providers was a barrier to consenting to the newly established service. Discussion/conclusion: Little is known about the characteristics which determine the uptake of retinal screening among those with diabetes in Ireland. Findings from this research will inform the ongoing implementation of the national diabetic retinopathy screening programme and its advertising and recruitment activities. Lessons learned: It is important that efforts to increase the uptake of the NDRSP include increasing the awareness around this change in service provision among members of the target population. Limitations: In the absence of national level data, quantitative analysis relied on data from two primary health care centres. Future research: This study is part of an ongoing evaluation of the National Clinical Programme for Diabetes. Findings from this research will be verified and refined during a multiple case study in four geographical regions in Ireland.

Modelling the cost-effectiveness of adopting risk-stratified approaches to extended screening intervals in the national diabetic retinopathy screening programme in Scotland.

To assess the cost-effectiveness of adopting risk-stratified approaches to extended screening intervals in the national diabetic retinopathy screening programme in Scotland. A continuous-time hidden Markov model was fitted to national longitudinal screening data to derive transition probabilities between observed non-referable and referable retinopathy states. These were incorporated in a decision model simulating progression, costs and visual acuity outcomes for a synthetic cohort with a covariate distribution matching that of the Scottish diabetic screening population. The cost-effectiveness of adopting extended (2-year) screening for groups with no observed retinopathy was then assessed over a 30-year time horizon. Individuals with a current grade of no retinopathy on two consecutive screening episodes face the lowest risk of progressing to referable disease. For the cohort as a whole, the incremental cost per quality-adjusted life year gained for annual vs. biennial screening ranged from approximately £74 000 (for those with no retinopathy and a prior observed grade of mild or observable background retinopathy) to approximately £232 000 per quality-adjusted life year gained (for those with no retinopathy on two consecutive screening episodes). The corresponding incremental cost-effectiveness ratios in the subgroup with Type 1 diabetes were substantially lower; approximately £22 000 to £85 000 per quality-adjusted life year gained, respectively. Biennial screening for individuals with diabetes who have no retinopathy is likely to deliver significant savings for a very small increase in the risk of adverse visual acuity and quality of life outcomes. There is greater uncertainty regarding the long-term cost-effectiveness of adopting biennial screening in younger people with Type 1 diabetes.

Trends in the incidence of visual impairment due to diabetic retinopathy in Ireland, 2004–2013

Background Diabetic retinopathy is a leading cause of visual impairment (VI). The last study to report the trends of blindness due to diabetic retinopathy was carried out in 2003 and since then a national diabetic retinopathy screening programme has been introduced (2013). Contemporary data are needed to evaluate the future impact of screening. The aim was to describe trends in the incidence and prevalence of blindness due to diabetic …

OP26 Trends in the incidence of visual impairment due to diabetic retinopathy among adults in the republic of ireland, 2004–2013

Background Diabetic retinopathy is a leading cause of visual impairment (VI). The last study to report the trends of VI due to diabetic retinopathy was carried out in 2003 and since then a national diabetic retinopathy screening programme has been introduced (2013). Contemporary data are needed to evaluate the future impact of screening. The aim was to describe trends in the incidence and prevalence of visual impairment due to diabetic retinopathy in the adult population in Ireland between 2004 and 2013. Methods Data on VI due to diabetic retinopathy in adults aged 18 years or over who are listed with the National Council for the Blind Ireland (NCBI), (January 2004–December 2013) were analysed. The number of new registrations due to diabetic retinopathy was obtained for each year. Population estimates for Ireland were obtained from the Central Statistics Office. Data from four nationally representative studies was used to estimate the annual prevalence of self-reported diagnosed diabetes in adults aged 18 years and over. Incidence and prevalence rates of VI due to diabetic retinopathy were calculated in both the adult population with diagnosed diabetes and the total adult population. Cuzick’s trend test was used to test for changes over time. Incidence and prevalence were expressed per 100,000 population. Analysis was carried out in Stata 13. Results In 2013, 601 adults with diabetic retinopathy were listed on the NCBI database, a prevalence of 403.5 (95% CI: 372.6–437.1) per 100 000 adult population with diabetes. From 2004 to 2013, 511 incident cases of VI due to diabetic retinopathy occurred; a higher proportion of new cases occurred in adults aged 66 years or over (≥66 years: 67% vs. 18–65 years: 33%). The incidence of VI due to diabetic retinopathy increased from 24.5 (95% CI: 16.3–36.9) in 2004 to 45.7 (95% CI: 36.0–57.9) in 2013 (p trend = 0.03) in the population with diabetes. Over the same time period, the incidence of VI due to diabetic retinopathy also increased in the general population from 7.5 per 100,000 [95% CI: 5.0–11.2] to 19.6 per 100,000 [95% CI: 15.5–24.9] (p trend = 0.01). Conclusion The incidence of VI due to diabetic retinopathy has increased over the past decade. This may be attributed in part to the rising prevalence of diabetes or an increase in detection due to the initiation of local retinal screening initiatives. Our findings will provide useful baseline statistics to monitor the impact of the national diabetic retinopathy screening program.

25th RCOphth Congress, President's Session paper: 25 years of progress in medical retina.

The quarter century since the foundation of the Royal College of Ophthalmologists has coincided with immense change in the subspecialty of medical retina, which has moved from being the province of a few dedicated enthusiasts to being an integral, core part of ophthalmology in every eye department. In age-related macular degeneration, there has been a move away from targeted, destructive laser therapy, dependent on fluorescein angiography to intravitreal injection therapy of anti-growth factor agents, largely guided by optical coherence tomography. As a result of these changes, ophthalmologists have witnessed a marked improvement in visual outcomes for their patients with wet age-related macular degeneration (AMD), while at the same time developing and enacting entirely novel ways of delivering care. In the field of diabetic retinopathy, this period also saw advances in laser technology and a move away from highly destructive laser photocoagulation treatment to gentler retinal laser treatments. The introduction of intravitreal therapies, both steroids and anti-growth factor agents, has further advanced the treatment of diabetic macular oedema. This era has also seen in the United Kingdom the introduction of a coordinated national diabetic retinopathy screening programme, which offers an increasing hope that the burden of blindness from diabetic eye disease can be lessened. Exciting future advances in retinal imaging, genetics, and pharmacology will allow us to further improve outcomes for our patients and for ophthalmologists specialising in medical retina, the future looks very exciting but increasingly busy.

Rates of referable eye disease in the Scottish National Diabetic Retinopathy Screening Programme

AimsDiabetic retinopathy screening aims to detect people at risk of visual loss due to proliferative diabetic retinopathy, but also refers cases of suspected macular oedema (maculopathy). At the introduction of...

Individual risk assessment and information technology to optimise screening frequency for diabetic retinopathy by Aspelund et al. (2011) Diabetologia 54:2525–2532

Individual risk assessment and information technology to optimise screening frequency for diabetic retinopathy by Aspelund et al. (2011) Diabetologia 54:2525–2532

Colour vision testing for diabetic retinopathy: a systematic review of diagnostic accuracy and economic evaluation

To determine the diagnostic performance and cost-effectiveness of colour vision testing (CVT) to identify and monitor the progression of diabetic retinopathy (DR). Major electronic databases including MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Database of Systematic Reviews were searched from inception to September 2008. A systematic review of the evidence was carried out according to standard methods. An online survey of National Screening Programme for Diabetic Retinopathy (NSPDR) clinical leads and programme managers assessed the diagnostic tools used routinely by local centres and their views on future research priorities. A decision tree and Markov model was developed to estimate the incremental costs and effects of adding CVT to the current NSPDR. In total, 25 studies on CVT met the inclusion criteria for the review, including 18 presenting 2 x 2 diagnostic accuracy data. The quality of studies and reporting was generally poor. Automated or computerised CVTs reported variable sensitivities (63-97%) and specificities (71-95%). One study reported good diagnostic accuracy estimates for computerised CVT plus retinal photography for detection of sight-threatening DR, but it included few cases of retinopathy in total. Results for pseudoisochromatic plates, anomaloscopes and colour arrangement tests were largely inadequate for DR screening, with Youden indices (sensitivity + specificity - 100%) close to zero. No studies were located that addressed patient preferences relating to CVT for DR. Retinal photography is universally employed as the primary method for retinal screening by centres responding to the online survey; none used CVT. The review of the economic evaluation literature found no previous studies describing the cost and effects of any type of CVT. Our economic evaluation suggested that adding CVT to the current national screening programme could be cost-effective if it adequately increases sensitivity and is relatively inexpensive. The deterministic base-case analysis indicated that the cost per quality-adjusted life-year gained may be 6364 pounds and 12,432 pounds for type 1 and type 2 diabetes respectively. However, probabilistic sensitivity analysis highlighted the substantial probability that CVT is not diagnostically accurate enough to be either an effective or a cost-effective addition to current screening methods. The results of the economic model should be treated with caution as the model is based on only one small study. There is insufficient evidence to support the use of CVT alone, or in combination with retinal photography, as a method for screening for retinopathy in patients with diabetes. Better quality diagnostic accuracy studies directly comparing the incremental value of CVT in addition to retinal photography are needed before drawing conclusions on cost-effectiveness. The most frequently cited preference for future research was the use of optical coherence tomography for the detection of clinically significant macular oedema.

Diabetes related complications – the Moorfields Diabetes Survey

Abstract Purpose: The aim of this study was to establish characteristics of patients with diabetes mellitus (DM) attending Moorfields Eye Hospital (MEH) before implementation of the national diabetic retinopathy (DR) screening programme. Methods: Patients with DM attending MEH Medical Retina Clinics during a 4 week time period were interviewed about DM, its complications and knowledge and expectations on laser treatment. Results: In 4 weeks, 830 patients with DM were identified, of whom 4.3% were registered partially sighted and 4.7% registered blind. 141 did not attend, 109 could/would not be interviewed and 580 interviews were conducted. Interviewed patients were similar to those not except for previous laser treatment (p=0.016). The median duration of DM was 10 years (0.3‐52 years); 74.3% had Type 2 DM; 64.8% had hypertension. A high proportion of patients had at least one diabetic complication (heart disease 24%; stroke 9.7%; diabetic neuropathy 48.9%; diabetic nephropathy 13.4%); 13.1% did not understand the relationship of DM with DR. In the past 61.5% and 64.1% patients had fluorescein angiography (FFA) and laser treatment; on the day of the interview 5.8% had FFA and 13.4% laser. Despite full consent, 51.6% did not understand how long it took the laser treatment to work or expected it to take effect immediately; 16.6% expected to have only one treatment ever. Only 20.9% were members of Diabetes UK. Conclusions: Patients currently attending eye clinics have many diabetes related complications. With full implementation of the National Screening Programme for DR this percentage is expected to rise. Careful planning of ophthalmic services needs to be undertaken to accommodate the need for services for patients with multiple diabetes related complications.

Current status of screening for diabetic retinopathy in the UK.

This article reviews the current status of retinopathy screening schemes in the UK. There is evidence that high-quality diabetic retinopathy screening schemes are in existence but provision is patchy. Many health authorities have ad hoc screening programmes reaching only about 60% of patients, with unacceptable or undocumented efficacy and minimal quality control. Several models of screening are currently in use with the current preferred option being camera-based screening. Digital imaging systems offer the best prospects for image acquisition, although at present evidence of adequate effectiveness only exists for 35 mm film-based systems. The final report of the National Diabetic Retinopathy Screening Programme commissioned by the UK National Screening Committee for inclusion into the national service framework for diabetes, is thus eagerly awaited and should set standards for screening programmes, in order to improve the care of all those with diabetes. Quality assurance will be the main driver in the immediate future of improvements in screening programmes. Research data will provide the evidence to refine techniques and set targets in the longer term, with the emphasis on cost-effectiveness and quality of life.

The potential impact of a National Diabetic Retinopathy Screening Programme on a department of medical illustration

Diabetic retinopathy screening programmes in the UK vary tremendously in quality, methods used, and frequency of screening. Indeed, many areas have no local screening service at all. The United Kingdom National Screening Committee has compiled and published a series of recommendations for a national risk reduction programme for diabetic retinopathy based on a screening programme. This paper will examine the primary recommendations of the committee and use the diabetic retinopathy screening programme currently running at Brighton Health Care NHS Trust as a model to demonstrate the potential impact the recommendations may have on an established programme. This will also give some indication of the resources required for any department not currently running a service.