Diabetic Eye Screening Programme Research Articles

Individualised screening for diabetic retinopathy: the ISDR study—rationale, design and methodology for a randomised controlled trial comparing annual and individualised risk-based variable-interval screening

IntroductionCurrently, all people with diabetes (PWD) aged 12 years and over in the UK are invited for screening for diabetic retinopathy (DR) annually. Resources are not increasing despite a 5%...

Prevalence of and Risk Factors for Diabetic Retinopathy in a Rural Chinese Population: The Yangxi Eye Study.

To investigate the prevalence and determinants of diabetic retinopathy (DR) among older adults in rural Southern China. Using random cluster sampling, persons aged 50 years or older were randomly selected in rural Yangxi County, Guangdong Province, China. All participants underwent a standardized interview, fundus photography, and point of service glycosylated hemoglobin A1c (HbA1c) testing. Diabetes mellitus (DM) was diagnosed based on confirmed medical history or HbA1c ≥6.5%. Fundus photographs were graded for DR and diabetic macular edema (DME) based on the United Kingdom National Diabetic Eye Screening Program guidelines. Prevalence of and risk factors for DR and vision-threatening diabetic retinopathy (VTDR) were evaluated. Among 5825 subjects who participated (90.7% response rate) in the Yangxi Eye Study, 562 (9.6%) were diagnosed with DM, including 79 (14.1%) known and 483 new (85.9%) cases. Among DM cases, 476 (84.7%) had gradable fundus photos. The prevalence of any DR and VTDR were 8.19% (95% confidence interval [CI] 5.9-11.0) and 5.25% (95% CI 3.43-7.66), respectively. These figures were 23.9% and 12.7% for known and 5.43% and 3.95% for new DM cases. Risk factors for any DR were higher HbA1c level (OR [odds ratio] per unit 1.34, P < 0.001), longer duration of DM (OR per year = 2.29, P < 0.001) and having previously undergone cataract surgery (OR 4.11, P < 0.030). Our study found a lower prevalence of DR among adults 50 years and older than in previously reports. Perhaps this difference can be explained by the short duration of most cases.

Accuracy of trained rural ophthalmologists versus non-medical image graders in the diagnosis of diabetic retinopathy in rural China

Background/aimsTo determine the diagnostic accuracy of trained rural ophthalmologists and non-medical image graders in the assessment of diabetic retinopathy (DR) in rural China.MethodsConsecutive patients with diabetes mellitus were examined from...

Diabetes – 2 The single common grading pathway, grading overview and non-sight threatening disease

Continuing our series on diabetic retinopathy, Peter Mitchell offers an overview of the Grading Scheme used in English National Diabetic Eye Screening Programme and discusses the management of non-sight threatening diabetes eye disease detected during the grading process based on the final outcome grade.

Diabetes – part 1 - An overview of the NHS Diabetic Eye Screening (DES) programme

Peter Mitchell discuss the principles and protocols of the English National Diabetic Eye Screening Programme and examines its impact upon the detection and management of diabetes eye disease and how appropriate referral when sight-threatening eye disease is detected can prevent sight loss.

A classification model for predicting diabetic retinopathy based on patient characteristics and biochemical measures

Purpose: In the United Kingdom (UK), The NHS Diabetic Eye Screening Program offers an annual eye examination to all people with diabetes aged 12 or over, aiming at the early detection of people at high risk of visual loss due to diabetic retinopathy. The purpose of this study was the design of a model to predict patients at risk of developing retinopathy with the use of patient characteristics and clinical measures. Methods: We investigated data from 2011 to 2016 from the population-based Diabetic Eye Screening Program in East Anglia. The data comprised retinal eye screening results, patient characteristics, and routine biochemical measures of HbA1c, blood pressure, Albumin to Creatinine ratio (ACR), estimated Glomerular Filtration rate (eGFR), serum creatinine, cholesterol and Body Mass Index (BMI). Individuals were classified according to the presence or absence of retinopathy as indicated by their retinal eye examinations. A lasso regression, random forest, gradient boosting machine and regularized gradient boosting model were built and cross-validated for their predictive ability. Results: A total of 6,375 subjects with recorded information for all available biochemical measures were identified from the cohorts. Of these, 5,969 individuals had no signs of diabetic retinopathy. Of the remainder 406 individuals with signs of diabetic retinopathy, 352 had background diabetic retinopathy and 54 had referable diabetic retinopathy. The highest value of the10-fold cross-validated Area under the Curve (AUC) was achieved by the gradient boosting machine 0.73 ± 0.03 and the minimum required set of variables to yield this performance included 4 variables: duration of diabetes, HbA1c, ACR and age. A subsequent analysis on the predictive power of the biochemical measures showed that when HbA1c and ACR measurements were available for longer time periods, the performance of the models was greatly enhanced. When HbA1c and ACR measurements for a 5-year period prior to the event of study were available, gradient boosting machine cross-validated AUC was 0.77 ± 0.04 in comparison to the cross-validated AUC of 0.68 ± 0.04 when only information for the 1-year period for these variables was available. Similarly, an increment from 0.70 ± 0.02 to 0.75 ± 0.04 was observed with random forest. The dataset with the 1-year measurements comprised 4,857 subjects, of whom, 4,572 had no retinopathy and the remainder 285 had signs of retinopathy. The dataset with the 5-year measurements comprised 757 subjects, of whom, 696 had no retinopathy and the remainder 51 had signs of retinopathy. Conclusions: The utilization of patient information and routine biochemical measures can be used to identify patients at risk of developing retinopathy. The effective differentiation between patients with and without retinopathy could significantly reduce the number of screening visits without compromising patients’ health.

Incentives in Diabetic Eye Assessment by Screening (IDEAS) trial: a three-armed randomised controlled trial of financial incentives

BackgroundThe UK national diabetic eye screening (DES) programme invites diabetic patients aged &gt; 12 years annually. Simple and cost-effective methods are needed to increase screening uptake. This trial tests the impact on uptake of two financial incentive schemes, based on behavioural economic principles.ObjectivesTo test whether or not financial incentives encourage screening attendance. Secondarily to understand if the type of financial incentive scheme used affects screening uptake or attracts patients with a different sociodemographic status to regular attenders. If financial incentives were found to improve attendance, then a final objective was to test cost-effectiveness.DesignThree-armed randomised controlled trial.SettingDES clinic within St Mary’s Hospital, London, covering patients from the areas of Kensington, Chelsea and Westminster.ParticipantsPatients aged ≥ 16 years, who had not attended their DES appointment for ≥ 2 years.Interventions(1) Fixed incentive – invitation letter and £10 for attending screening; (2) probabilistic (lottery) incentive – invitation letter and 1% chance of winning £1000 for attending screening; and (3) control – invitation letter only.Main outcome measuresThe primary outcome was screening attendance. Rates for control versus fixed and lottery incentive groups were compared using relative risk (RR) and risk difference with corresponding 95% confidence intervals (CIs).ResultsA total of 1274 patients were eligible and randomised; 223 patients became ineligible before invite and 1051 participants were invited (control,n = 435; fixed group,n = 312; lottery group,n = 304). Thirty-four (7.8%, 95% CI 5.29% to 10.34%) control, 17 (5.5%, 95% CI 2.93% to 7.97%) fixed group and 10 (3.3%, 95% CI 1.28% to 5.29%) lottery group participants attended. Participants offered incentives were 44% less likely to attend screening than controls (RR 0.56, 95% CI 0.34 to 0.92). Examining incentive groups separately, the lottery group were 58% less likely to attend screening than controls (RR 0.42, 95% CI 0.18 to 0.98). No significant differences were found between fixed incentive and control groups (RR 0.70, 95% CI 0.35 to 1.39) or between fixed and lottery incentive groups (RR 1.66, 95% CI 0.65 to 4.21). Subgroup analyses showed no significant associations between attendance and sociodemographic factors, including gender (female vs. male, RR 1.25, 95% CI 0.77 to 2.03), age (≤ 65 years vs. &gt; 65 years, RR 1.26, 95% CI 0.77 to 2.08), deprivation [0–20 Index of Multiple Deprivation (IMD) decile vs. 30–100 IMD decile, RR 1.12, 95% CI 0.69 to 1.83], years registered [mean difference (MD) –0.13, 95% CI –0.69 to 0.43], and distance from screening location (MD –0.18, 95% CI –0.65 to 0.29).LimitationsDespite verification, some address details may have been outdated, and high ethnic diversity may have resulted in language barriers for participants.ConclusionsThose receiving incentives were not more likely to attend a DES than those receiving a usual invitation letter in patients who are regular non-attenders. Both fixed and lottery incentives appeared to reduce attendance. Overall, there is no evidence to support the use of financial incentives to promote diabetic retinopathy screening. Testing interventions in context, even if they appear to be supported by theory, is important.Future workFuture research, specifically in this area, should focus on identifying barriers to screening and other non-financial methods to overcome them.Trial registrationCurrent Controlled Trials ISRCTN14896403.FundingThis project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full inHealth Services and Delivery Research; Vol. 5, No. 15. See the NIHR Journals Library website for further project information.

The English National Screening Programme for diabetic retinopathy 2003\u20132016

The aim of the English NHS Diabetic Eye Screening Programme is to reduce the risk of sight loss amongst people with diabetes by the prompt identification and effective treatment if necessary of sight-threatening diabetic retinopathy, at the appropriate stage during the disease process. In order to achieve the delivery of evidence-based, population-based screening programmes, it was recognised that certain key components were required. It is necessary to identify the eligible population in order to deliver the programme to the maximum number of people with diabetes. The programme is delivered and supported by suitably trained, competent, and qualified, clinical and non-clinical staff who participate in recognised ongoing Continuous Professional Development and Quality Assurance schemes. There is an appropriate referral route for those with screen-positive disease for ophthalmology treatment and for assessment of the retinal status in those with poor-quality images. Appropriate assessment of control of their diabetes is also important in those who are screen positive. Audit and internal and external quality assurance schemes are embedded in the service. In England, two-field mydriatic digital photographic screening is offered annually to all people with diabetes aged 12 years and over. The programme commenced in 2003 and reached population coverage across the whole of England by 2008. Increasing uptake has been achieved and the current annual uptake of the programme in 2015–16 is 82.8% when 2.59 million people with diabetes were offered screening and 2.14 million were screened. The benefit of the programme is that, in England, diabetic retinopathy/maculopathy is no longer the leading cause of certifiable blindness in the working age group.

Can Commercially Available Handheld Retinal Cameras Effectively Screen Diabetic Retinopathy?

Organizations that care for people with diabetes have increasingly adopted telemedicine-based diabetic retinopathy screening (TMDRS) as a way to increase adherence to recommended retinal exams. Recently, handheld retinal cameras have emerged as a low-cost, lightweight alternative to traditional bulky tabletop retinal cameras. Few published clinical trials have been performed on handheld retinal cameras. Peer-reviewed articles about commercially available handheld retinal cameras have concluded that they are a usable alternative for TMDRS, however, the clinical results presented in these articles do not meet criteria published by the United Kingdom Diabetic Eye Screening Programme and the American Academy of Ophthalmology. The future will likely remedy the shortcomings of currently available handheld retinal cameras, and will create more opportunities for preventing diabetic blindness.

An observational study to assess if automated diabetic retinopathy image assessment software can replace one or more steps of manual imaging grading and to determine their cost-effectiveness.

Diabetic retinopathy screening in England involves labour-intensive manual grading of retinal images. Automated retinal image analysis systems (ARIASs) may offer an alternative to manual grading. To determine the screening performance and cost-effectiveness of ARIASs to replace level 1 human graders or pre-screen with ARIASs in the NHS diabetic eye screening programme (DESP). To examine technical issues associated with implementation. Observational retrospective measurement comparison study with a real-time evaluation of technical issues and a decision-analytic model to evaluate cost-effectiveness. A NHS DESP. Consecutive diabetic patients who attended a routine annual NHS DESP visit. Retinal images were manually graded and processed by three ARIASs: iGradingM (version 1.1; originally Medalytix Group Ltd, Manchester, UK, but purchased by Digital Healthcare, Cambridge, UK, at the initiation of the study, purchased in turn by EMIS Health, Leeds, UK, after conclusion of the study), Retmarker (version 0.8.2, Retmarker Ltd, Coimbra, Portugal) and EyeArt (Eyenuk Inc., Woodland Hills, CA, USA). The final manual grade was used as the reference standard. Arbitration on a subset of discrepancies between manual grading and the use of an ARIAS by a reading centre masked to all grading was used to create a reference standard manual grade modified by arbitration. Screening performance (sensitivity, specificity, false-positive rate and likelihood ratios) and diagnostic accuracy [95% confidence intervals (CIs)] of ARIASs. A secondary analysis explored the influence of camera type and patients' ethnicity, age and sex on screening performance. Economic analysis estimated the cost per appropriate screening outcome identified. A total of 20,258 patients with 102,856 images were entered into the study. The sensitivity point estimates of the ARIASs were as follows: EyeArt 94.7% (95% CI 94.2% to 95.2%) for any retinopathy, 93.8% (95% CI 92.9% to 94.6%) for referable retinopathy and 99.6% (95% CI 97.0% to 99.9%) for proliferative retinopathy; and Retmarker 73.0% (95% CI 72.0% to 74.0%) for any retinopathy, 85.0% (95% CI 83.6% to 86.2%) for referable retinopathy and 97.9% (95% CI 94.9 to 99.1%) for proliferative retinopathy. iGradingM classified all images as either 'disease' or 'ungradable', limiting further iGradingM analysis. The sensitivity and false-positive rates for EyeArt were not affected by ethnicity, sex or camera type but sensitivity declined marginally with increasing patient age. The screening performance of Retmarker appeared to vary with patient's age, ethnicity and camera type. Both EyeArt and Retmarker were cost saving relative to manual grading either as a replacement for level 1 human grading or used prior to level 1 human grading, although the latter was less cost-effective. A threshold analysis testing the highest ARIAS cost per patient before which ARIASs became more expensive per appropriate outcome than human grading, when used to replace level 1 grader, was Retmarker £3.82 and EyeArt £2.71 per patient. The non-randomised study design limited the health economic analysis but the same retinal images were processed by all ARIASs in this measurement comparison study. Retmarker and EyeArt achieved acceptable sensitivity for referable retinopathy and false-positive rates (compared with human graders as reference standard) and appear to be cost-effective alternatives to a purely manual grading approach. Future work is required to develop technical specifications to optimise deployment and address potential governance issues. The National Institute for Health Research (NIHR) Health Technology Assessment programme, a Fight for Sight Grant (Hirsch grant award) and the Department of Health's NIHR Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital and the University College London Institute of Ophthalmology.

Stratifying the NHS Diabetic Eye Screening Programme: into the unknown?

In this commentary, we consider the recent recommendation by the UK National Screening Committee (NSC) that people with diabetes at low risk of sight loss should be invited to screening every 2 years rather than annually [1]. We broadly support this recommendation but believe that there are important outstanding questions that require attention before such a policy is implemented. We discuss the decision in the context of the history of the NHS Diabetic Eye Screening Programme (NDESP) and reflect on the current state of evidence, including work cited by the NSC [1–4].

Diabetic eye screening: A pragmatic approach

Introduction: The primary aim of the NHS diabetic eye screening programme (DESP) is to reduce the risk of sight loss among people with diabetes. This is achieved through prompt identification and effective treatment of sight-threatening diabetic retinopathy. Currently, no nationally agreed referral standards for non-diabetic retinopathy that may also be identified on screening images exist. Methods: Referrals of ‘arterial emboli’ from a single DESP to one local hospital eye clinic over a one-year period were analysed, with information collected on assessments and pathways for each patient. Results: Retinal arterial emboli do not have ophthalmic treatment but require a full systemic workup due to the potential for cardiovascular and cerebrovascular complications in these already higher risk patients. Referral to the eye clinic introduces undue and avoidable delay in pertinent investigations being carried out. Conclusions: We propose and have implemented a new shorter pathway for the referral of patients with retinal arterial emboli from the screening programme directly to the hospital's rapid access stroke clinic, where necessary investigations can be initiated in a timely and structured manner. This will lead to better risk stratification for medical and surgical treatment at an earlier time point, resulting in better and safer care for patients. It will also reduce the number of unnecessary appointments in the outpatient eye clinic, saving both cost and time.

Diagnosis of retinopathy in children younger than 12 years of age: implications for the diabetic eye screening guidelines in the UK.

AimTo assess whether the current starting age of 12 is suitable for diabetic retinopathy (DR) screening and whether diabetes duration should be taken into account when deciding at what age to start screening patients.Materials and methodsA retrospective analysis of 143 patients aged 12 years or younger who attended diabetic eye screening for the first time in the Birmingham, Solihull and Black Country Diabetic Eye Screening Programme was performed.ResultsThe mean age of the patients was 10.7 (7-12) years with 73 out of 143 aged below 12 years and 70 were 12 years of age. 98% had type 1 diabetes and mean diabetes duration was 5 (1 month-11 years) years. For those younger than 12 years, 7/73 (9.6%) had background DR (BDR), of these mean diabetes duration was 7 years (6-8). The youngest patient to present with DR was aged 8 years. In those aged 12 years, 5/70 (7.1%) had BDR; of these mean diabetes duration was 8 years (6-11). No patient developed DR before 6 years duration in either group.ConclusionsThe results show that no patient younger than the age of 12 had sight-threatening DR (STDR), but BDR was identified. Based on the current mission statement of the Diabetic Eye Screening Programme to identify STDR, 12 years of age is confirmed as the right age to start screening, but if it is important to diabetic management to identify first development of DR, then screening should begin after 6 years of diabetes diagnosis.

Does delay in referral of proliferative diabetic retinopathy from the diabetic eye screening programme lead to visual loss?

AimsTo ascertain the effect on visual acuity (VA) of a delay in Hospital Eye Service (HES) consultation for patients referred with proliferative diabetic retinopathy (PDR; R3) from the Diabetic Eye Screening Programme (DESP).MethodsAll patients referred to Moorfields Eye Hospital from DESP between April and December 2013 with a referral diagnosis of PDR in at least one eye were eligible. Screening programme VA was compared with VA at first HES appointment and final follow-up appointment. Reasons for any VA loss were noted.ResultsA total of 86 patients were included. Of these, 28 (33%) were seen in more than 4 weeks after their DESP referral. At first HES appointment, 39 (45%) patients were graded as having active PDR in at least one eye. Delay in referral did not significantly predict the likelihood of vision loss in all patients referred (χ(2), P=0.49) or in just those patients with a definitive HES diagnosis of active PDR (χ(2), P=1.00). In only 3 patients with active PDR was a delay in presentation thought to have led directly to VA loss.ConclusionsThere may be minimal short-term visual consequence in several weeks of delayed referral for many patients with a diagnosis of R3. However, the national guidance remains important. This is due to the occasional patient at very high risk of vision loss and the many gains for the patients in terms of time to properly assess medical and ocular conditions and counsel and consent them for treatment where necessary.

Incentives in Diabetic Eye Assessment by Screening (IDEAS): study protocol of a three-arm randomized controlled trial using financial incentives to increase screening uptake in London.

BackgroundDiabetes is an increasing public health problem in the UK and globally. Diabetic retinopathy is a microvascular complication of diabetes, and is one of the leading causes of blindness in the UK working age population. The diabetic eye screening programme in England aims to invite all people with diabetes aged 12 or over for retinal photography to screen for the presence of diabetic retinopathy. However, attendance rates are only 81 %, leaving many people at risk of preventable sight loss.MethodsThis is a three arm randomized controlled trial to investigate the impact of different types of financial incentives (based on principles from behavioral economics) on increasing attendance at diabetic eye screening appointments in London. Eligible participants will be aged 16 or over, and are those who have been invited to screening appointments annually, but who have not attended, or telephoned to rearrange an appointment, within the last 24 months.Eligible participants will be randomized to one of three conditions:Control condition (usual invitation letter)Fixed incentive condition (usual invitation letter, including a voucher for £10 if they attend their appointment)Probabilistic incentive condition (invitation letter, including a voucher for a 1 in 100 chance of winning £1000 if they attend their appointment).Participants will be sent invitation letters, and the primary outcome will be whether or not they attend their appointment. One thousand participants will be included in total, randomized with a ratio of 1.4:1:1. In order to test whether the incentive scheme has a differential impact on patients from different demographic or socio-economic groups, information will be recorded on age, gender, distance from screening center, socio-economic status and length of time since they were last screened. A cost-effectiveness analysis will also be performed.DiscussionThis study will be the first trial of financial incentives for improving uptake of diabetic eye screening. If effective, the intervention may suggest a cost-effective way to increase screening rates, thus reducing unnecessary blindness.Trial registrationISRCTN14896403, 25 February 2016

Telemedicine and Diabetic Retinopathy: Review of Published Screening Programs.

Diabetic Retinopathy (DR) is a leading cause of blindness worldwide even though successful treatments exist. Improving screening and treatment could avoid many cases of vision loss. However, due to an increasing prevalence of diabetes, traditional in-person screening for DR for every diabetic patient is not feasible. Telemedicine is one viable solution to provide high-quality and efficient screening to large number of diabetic patients. To provide a narrative review of large DR telemedicine screening programs. Articles were identified through a comprehensive search of the English-language literature published between 2000 and 2014. Telemedicine screening programs were included for review if they had published data on at least 150 patients and had available validation studies supporting their model. Screening programs were then categorized according to their American Telemedicine Association Validation Level. Seven programs from the US and abroad were identified and included in the review. Three programs were Category 1 programs (Ophdiat, EyePacs, and Digiscope), two were Category 2 programs (Eye Check, NHS Diabetic Eye Screening Program), and two were Category 3 programs (Joslin Vision Network, Alberta Screening Program). No program was identified that claimed category 4 status. Programs ranged from community or city level programs to large nationwide programs including millions of individuals. The programs demonstrated a high level of clinical accuracy in screening for DR. There was no consensus amongst the programs regarding the need for dilation, need for stereoscopic images, or the level of training for approved image graders. Telemedicine programs have been clinically validated and successfully implemented across the globe. They can provide a high-level of clinical accuracy for screening for DR while improving patient access in a cost-effective and scalable manner.

Development of a cost-effectiveness model for optimisation of the screening interval in diabetic retinopathy screening.

The English NHS Diabetic Eye Screening Programme was established in 2003. Eligible people are invited annually for digital retinal photography screening. Those found to have potentially sight-threatening diabetic retinopathy (STDR) are referred to surveillance clinics or to Hospital Eye Services. To determine whether personalised screening intervals are cost-effective. Risk factors were identified in Gloucestershire, UK using survival modelling. A probabilistic decision hidden (unobserved) Markov model with a misgrading matrix was developed. This informed estimation of lifetime costs and quality-adjusted life-years (QALYs) in patients without STDR. Two personalised risk stratification models were employed: two screening episodes (SEs) (low, medium or high risk) or one SE with clinical information (low, medium-low, medium-high or high risk). The risk factor models were validated in other populations. Gloucestershire, Nottinghamshire, South London and East Anglia (all UK). People with diabetes in Gloucestershire with risk stratification model validation using data from Nottinghamshire, South London and East Anglia. Personalised risk-based algorithm for screening interval; cost-effectiveness of different screening intervals. Data were obtained in Gloucestershire from 12,790 people with diabetes with known risk factors to derive the risk estimation models, from 15,877 people to inform the uptake of screening and from 17,043 people to inform the health-care resource-usage costs. Two stratification models were developed: one using only results from previous screening events and one using previous screening and some commonly available GP data. Both models were capable of differentiating groups at low and high risk of development of STDR. The rate of progression to STDR was 5 per 1000 person-years (PYs) in the lowest decile of risk and 75 per 1000 PYs in the highest decile. In the absence of personalised risk stratification, the most cost-effective screening interval was to screen all patients every 3 years, with a 46% probability of this being cost-effective at a £30,000 per QALY threshold. Using either risk stratification models, screening patients at low risk every 5 years was the most cost-effective option, with a probability of 99-100% at a £30,000 per QALY threshold. For the medium-risk groups screening every 3 years had a probability of 43-48% while screening high-risk groups every 2 years was cost-effective with a probability of 55-59%. The study found that annual screening of all patients for STDR was not cost-effective. Screening this entire cohort every 3 years was most likely to be cost-effective. When personalised intervals are applied, screening those in our low-risk groups every 5 years was found to be cost-effective. Screening high-risk groups every 2 years further improved the cost-effectiveness of the programme. There was considerable uncertainty in the estimated incremental costs and in the incremental QALYs, particularly with regard to implications of an increasing proportion of maculopathy cases receiving intravitreal injection rather than laser treatment. Future work should focus on improving the understanding of risk, validating in further populations and investigating quality issues in imaging and assessment including the potential for automated image grading. Integrated Research Application System project number 118959. The National Institute for Health Research Health Technology Assessment programme.

Access to a local Digital Diabetic Retinopathy Screening Service

Background: Diabetic retinopathy is the second most frequent cause of registerable blindness in the working-age population in the UK. Despite the implementation of the NHS Diabetic Eye Screening Programme in England and Wales, many patients with diabetes continue to become sight impaired. Aim: The purpose of this study was to better understand the impact of a Digital Diabetic Retinopathy Screening Service (DDRSS) provided to residents of Walsall in the West Midlands, UK. Methods: An analysis of data from the UK National Diabetes Audit and a plot of the location of DDRSS providers against a ‘heat map’ of the resident population density of those aged 60 years and over in Walsall provided a gauge of the impact of the service, including accessibility to and reach of the service. Results: DDRSS providers were not necessarily located in residential areas of older people, nor within a 15-minute walking distance for a significant proportion of residents. The DDRSS pathway extensively involves community optometrists but appears to under-deliver in meeting the key performance indicators of the service. Conclusions: There is a need to better understand the barriers to the uptake of the DDRSS in Walsall. The feasibility of a mobile DDRSS service is also being considered so that the areas not within easy access of residents can be provided with the screening service. Further consideration should be given to the provision of the service to patients in their homes, and in residential homes and day-care centres.

Influence of primary care practices on patients' uptake of diabetic retinopathy screening: a qualitative case study.

BackgroundThe NHS Diabetic Eye Screening Programme aims to reduce the risk of sight loss among people with diabetes in England by enabling prompt diagnosis of sight-threatening retinopathy. However, the rate of screening uptake between practices can vary from 55% to 95%. Existing research focuses on the impact of patient demographics but little is known about GP practice-related factors that can make a difference.AimTo identify factors contributing to high or low patient uptake of retinopathy screening.Design and settingQualitative case-based study; nine purposively selected GP practices (deprived/affluent; high/low screening uptake) in three retinopathy screening programme areas.MethodsSemi-structured interviews were conducted with patients, primary care professionals, and screeners. A comparative case-based analysis was carried out to identify factors related to high or low screening uptake.ResultsEight possible factors that influenced uptake were identified. Five modifiable factors related to service and staff interactions: communication with screening services; contacting patients; integration of screening with other care; focus on the newly diagnosed; and perception of non-attenders. Three factors were non-modifiable challenges related to practice location: level of deprivation; diversity of ethnicities and languages; and transport and access. All practices adopted strategies to improve uptake, but the presence of two or more major barriers made it very hard for practices to achieve higher uptake levels.ConclusionsA range of service-level opportunities to improve screening attendance were identified that are available to practices and screening teams. More research is needed into the complex interfaces of care that make up retinopathy screening.

Grader agreement, and sensitivity and specificity of digital photography in a community optometry-based diabetic eye screening program.

BackgroundDigital retinal photography with mydriasis is the preferred modality for diabetes eye screening. The purpose of this study was to evaluate agreement in grading levels between primary and secondary graders and to calculate their sensitivity and specificity for identifying sight-threatening disease in an optometry-based retinopathy screening program.MethodsThis was a retrospective study using data from 8,977 patients registered in the North Nottinghamshire retinal screening program. In all cases, the ophthalmology diagnosis was used as the arbitrator and considered to be the gold standard. Kappa statistics were used to evaluate the level of agreement between graders.ResultsAgreement between primary and secondary graders was 51.4% and 79.7% for detecting no retinopathy (R0) and background retinopathy (R1), respectively. For preproliferative (R2) and proliferative retinopathy (R3) at primary grading, agreement between the primary and secondary grader was 100%. Where there was disagreement between the primary and secondary grader for R1, only 2.6% (n=41) were upgraded by an ophthalmologist. The sensitivity and specificity for detecting R3 was 78.2% and 98.1%, respectively. None of the patients upgraded from any level of retinopathy to R3 required photocoagulation therapy. The observed kappa between the primary and secondary grader was 0.3223 (95% confidence interval 0.2937–0.3509), ie, fair agreement, and between the primary grader and ophthalmology for R3 was 0.5667 (95% confidence interval 0.4557–0.6123), ie, moderate agreement.ConclusionThese data provide information on the safety of a community optometry-based retinal screening program for screening as a primary and as a secondary grader. The level of agreement between the primary and secondary grader at a higher level of retinopathy (R2 and R3) was 100%. Sensitivity and specificity for R3 were 78.2% and 98.1%, respectively. None of the false-negative results required photocoagulation therapy.