Incidence of diabetic retinopathy in people with type 2 diabetes mellitus attending the Diabetic Retinopathy Screening Service for Wales: retrospective analysis

Incidence of diabetic retinopathy and its predictors among adult patients with diabetes in Ethiopia: a frailty model

Background

Diabetic retinopathy (DR) is becoming a more widespread public concern worldwide, leading to visual impairments. It has become the leading cause of blindness among working-age adults globally, despite established treatments that can reduce the risk by 60%.

Objective

This study aimed to determine the incidence of diabetic retinopathy and its predictors among adult patients with diabetes in public hospitals in Central and Southern Ethiopia.

Methods

A hospital-based follow-up study was conducted in selected public hospitals in Central and Southern Ethiopia. A total of 376 participants of newly diagnosed adult diabetes were enrolled from 2015-2023 and the follow-up the date was from date of enrolment to the development of events. The data were collected by reviewing their records and entered in Epi-data version 4.6.0.2 and exported to STATA version 14 for analysis. Descriptive statistics of the variables were obtained. The Weibull model with gamma frailty distribution was fitted. Bivariable and multivariable analyses were done, and variables with a p-value less than 0.05 and a corresponding 95% confidence interval in the final model were used. The model of adequacy was checked.

Results

376 adult diabetic patient records were reviewed with the mean baseline age (± standard deviation) of 34.8±10 years. The univariate frailty was statistically significant (Theta=0.236 (0.131, 0.496)). A total of 376 adult patients with diabetes were followed for 682.894 person-years. Overall, an incidence rate of 14.06/100 person-years. Proteinuria (AHR = 2.21: 95% CI: 1.45, 3.57), cardiovascular disease (AHR = 2.23: 95% CI: 1.34, 4.03), and type II DM (AHR = 2.87: 95% CI: 1.30, 6.13) were identified as significant predictors of diabetic retinopathy.

Conclusion

Overall incidence rate of diabetic retinopathy was high. The most effective way to protect our vision from diabetic retinopathy is to manage diabetes effectively and offer support to high-risk individuals with diabetes. Therefore, healthcare professionals and relevant health authorities should target on addressing these factors in their initiatives to prevent diabetic retinopathy in diabetic patients.

Comparison of trauma and diabetes mellitus-induced transtibial amputees in terms of gait parameters and functional capacity

BACKGROUND

The aim of this study was to compare gait parameters, balance, weight-bearing symmetry, functional capacity, functional mobility, prosthesis satisfaction, and quality of life between individuals with diabetes mellitus-induced and traumatic transtibial amputations (TTAs).

METHODS

Ten individuals with traumatic transtibial amputation and 10 individuals with diabetes mellitus-induced transtibial amputation were included in the study. All participants in both the trauma and diabetes groups used a vacuum-assisted suction suspension system (VASS) and a carbon composite foot transtibial prosthesis. Gait analysis and weight-bearing symmetry were assessed using a computerized gait analysis system. Balance was evaluated with the Biodex Balance System (BBS), functional capacity with the Six-Minute Walk Test (6MWT), functional mobility with the Timed Up and Go Test (TUG) and the Stair Climbing Test (SCT), prosthesis satisfaction with the Trinity Amputation and Prosthesis Experience Scale (TAPES), and quality of life with the Short Form-36 (SF-36).

RESULTS

When comparing the traumatic and diabetic groups, significant differences favoring the trauma group were found in the following parameters: stride length (SL) (p=0.004), amputated limb step length (ASL) (p=0.019), non-affected limb step length (NSL) (p=0.005), balance assessment parameters of general postural stability (p=0.000), anteroposterior (A-P) postural stability (p=0.000), mediolateral (M-L) postural stability (p=0.007), SCT performance (p=0.000), and the activity restriction subsection of TAPES (p=0.029). No significant differences were observed in gait velocity, cadence, step width, weight-bearing percentage of the amputated and non-affected limbs, TUG performance, SF-36 scores, or the psychosocial adjustment, prosthesis satisfaction, and daily use time subsections of the TAPES.

CONCLUSION

In this study, the use of a VASS prosthesis in both traumatic and diabetic amputees had a positive effect on out-comes in the diabetic group, resulting in comparable results to those of the traumatic group. The fact that diabetic amputees used their prostheses as frequently as traumatic amputees, remained active, and benefited from the choice of prosthesis and suspension system provides valuable insights for healthcare professionals as a facilitating factor in rehabilitation.

Incidence of diabetic retinopathy and predictors among adult patients with diabetes in central and southern Ethiopia: a multicentre retrospective cohort study

OBJECTIVES

This study aimed to determine the incidence of diabetic retinopathy (DR) and predictors among adult patients with diabetes in central and southern Ethiopia.

DESIGN

A hospital-based retrospective cohort study was conducted.

SETTING

The study was conducted in selected public hospitals in central and southern Ethiopia.

PARTICIPANTS

A total of 376 adult participants newly diagnosed with diabetes were enrolled from 2015 to 2023, and the follow-up date was from the date of enrolment to the development of events.

OUTCOME MEASURES

The data were collected by reviewing their records and entered in EpiData V.4.6.0.2 and exported to STATA V.14 for analysis. Descriptive statistics of the variables were obtained. The Cox proportional hazards assumption was checked. The Cox regression model was used to determine the median time to develop DR and identify predictors of DR. Bivariable and multivariable analyses were done; variables with a value of p<0.05 and a corresponding 95% CI in the final model were used. The model of adequacy was checked.

RESULTS

Records of a total of 376 adult patients with diabetes were reviewed with a mean baseline age (±SD) of 34.8±10 years. Of the total study participants, half (189, 50.3%) were female. A total of 376 adult patients with diabetes were followed for 45 752 person-months (PMs). Overall, the incidence rate was 11.7 per 1000 PMs of observation. Positive proteinuria (adjusted HR (AHR)=2.19; 95% CI 1.18 to 4.08), hypertension (HTN) (AHR=2.23; 95% CI 1.39 to 3.55) and type 2 diabetes mellitus (AHR=2.89; 95% CI 1.19 to 7.05) were independently significant predictors of DR.

CONCLUSION

The overall incidence rate of DR (type 1 and type 2) was high. Adult patients with diabetes with HTN, proteinuria and type of diabetes were independent predictors of DR. The best strategy to protect our eyesight from DR is to control high glucose level and giving due attention to high-risk individuals with diabetes. Thus, health professionals and concerned health authorities should target these factors in their efforts to prevent DR among diabetics.

Changes in urine dipstick proteinuria and its relation to the risk of diabetic retinopathy and neuropathy

BACKGROUND

Proteinuria is considered as a predictor for cardiovascular complications in diabetes mellitus (DM). However, no study has examined the association between changes in proteinuria and the risk of diabetic microvascular complications.

METHODS

Study participants were 71,825 DM patients who received urine dipstick test for proteinuria both in 2003-2004 and 2006-2007. They were categorized into four groups according to changes in proteinuria over 3 years (negative: negative → negative, resolved: proteinuria ≥ 1+ → negative, incident: negative → proteinuria ≥ 1+, persistent: proteinuria ≥ 1+ → proteinuria ≥ 1+). Cox-proportional hazard model was used in assessing the adjusted hazard ratios (HR) and 95% confidence interval (CI) for incidence of retinopathy, and neuropathy (adjusted HR [95% CI]).

RESULT

In all of DM patients, risk for comprehensive incidence of retinopathy and neuropathy increased in all types of proteinuria changes. In type 1 DM, HR for retinopathy and neuropathy generally increased in order of negative (reference), resolved (2.175 [1.150-4.114] and 1.335 [0.909-1.961]), incident (2.088 [1.185-3.680] and 1.753 [1.275-2.409]), and persistent proteinuria (1.314 [0.418-4.134] and 2.098 [1.274-3.455]). This pattern of relationship was similarly observed in type 2 DM for retinopathy and neuropathy: negative (reference), resolved (1.490 [1.082-2.051] and 1.164 [0.988-1.371]), incident (1.570 [1.161-2.123] and 1.291 [1.112-1.500]), and persistent proteinuria (2.309 [1.407-3.788] and 1.272 [0.945-1.712]).

CONCLUSION

Risk for diabetic retinopathy and neuropathy generally increased in order of negative, resolved, incident, and persistent proteinuria. Once manifested proteinuria was associated with the increased risk of diabetic retinopathy and neuropathy even after remission of proteinuria.

Prevalence of diabetic retinopathy and its risk factors in rural patients with type 2 diabetes referring to Beijing Huairou Hospital, China

BACKGROUND

China has the largest population of diabetic patients worldwide. A diverse population and regional discrepancy in access to health care and diabetes management may lead to unique risk factors for diabetic retinopathy (DR) in different regions of China. This study aimed to evaluate the prevalence and risk factors of DR in rural patients with type 2 diabetes.

METHODS

This hospital-based cross-sectional study recruited a sample of 704 type 2 diabetic patients from rural areas referred to Beijing Huairou Hospital, China, from June 1, 2022, to June 1, 2023. The medical history, demographic information, and results of laboratory examinations of patients were collected and analyzed. The diagnosis of DR were performed by experienced ophthalmologists using mydriatic fundus photography.

RESULTS

Out of all patients, 53.8% were male and 46.2% were female. The mean age of patients and duration of diabetes were 54.9 ± 13.0 and 6.2 ± 4.5 years, respectively. The DR prevalence was 16.8%. The independent risk factors for DR in multivariate analysis were diabetes duration > 10 years (OR = 9.16, 95%CI = 5.49-15.30), fasting plasma glucose ≥ 7.2 mmol/L (OR = 3.25, 95%CI = 1.42-7.42), glycosylated hemoglobin ≥ 7% (OR = 6.49, 95%CI = 2.59-16.23), hypertension (OR = 1.59, 95%CI = 1.05-2.40), hyperlipidemia (OR = 2.16, 95%CI = 1.30-3.59), diabetic nephropathy (OR = 1.95, 95%CI = 1.17-3.23), high uric acid level (OR = 3.57, 95%CI = 1.56-8.15), high albumin to creatinine ratio (OR = 2.48, 95%CI = 1.06-5.82), and insulin treatment (OR = 1.79, 95%CI = 1.12-2.88).

CONCLUSIONS

This study evaluated the DR prevalence and its associated risk factors among type 2 diabetic patients from rural areas in Beijing's Huairou District, China. Paying attention to these risk factors may be useful in screening high-risk diabetic patients for DR and adopting early preventive and therapeutic interventions.

Extending the diabetic retinopathy screening intervals in Singapore: methodology and preliminary findings of a cohort study

BACKGROUND

The Diabetic Retinopathy Extended Screening Study (DRESS) aims to develop and validate a new DR/diabetic macular edema (DME) risk stratification model in patients with Type 2 diabetes (DM) to identify low-risk groups who can be safely assigned to biennial or triennial screening intervals. We describe the study methodology, participants' baseline characteristics, and preliminary DR progression rates at the first annual follow-up.

METHODS

DRESS is a 3-year ongoing longitudinal study of patients with T2DM and no or mild non-proliferative DR (NPDR, non-referable) who underwent teleophthalmic screening under the Singapore integrated Diabetic Retinopathy Programme (SiDRP) at four SingHealth Polyclinics. Patients with referable DR/DME (> mild NPDR) or ungradable fundus images were excluded. Sociodemographic, lifestyle, medical and clinical information was obtained from medical records and interviewer-administered questionnaires at baseline. These data are extracted from medical records at 12, 24 and 36 months post-enrollment. Baseline descriptive characteristics stratified by DR severity at baseline and rates of progression to referable DR at 12-month follow-up were calculated.

RESULTS

Of 5,840 eligible patients, 78.3% (n = 4,570, median [interquartile range [IQR] age 61.0 [55-67] years; 54.7% male; 68.0% Chinese) completed the baseline assessment. At baseline, 97.4% and 2.6% had none and mild NPDR (worse eye), respectively. Most participants had hypertension (79.2%) and dyslipidemia (92.8%); and almost half were obese (43.4%, BMI ≥ 27.5 kg/m2). Participants without DR (vs mild DR) reported shorter DM duration, and had lower haemoglobin A1c, triglycerides and urine albumin/creatinine ratio (all p < 0.05). To date, we have extracted 41.8% (n = 1909) of the 12-month follow-up data. Of these, 99.7% (n = 1,904) did not progress to referable DR. Those who progressed to referable DR status (0.3%) had no DR at baseline.

CONCLUSIONS

In our prospective study of patients with T2DM and non-referable DR attending polyclinics, we found extremely low annual DR progression rates. These preliminary results suggest that extending screening intervals beyond 12 months may be viable and safe for most participants, although our 3-year follow up data are needed to substantiate this claim and develop the risk stratification model to identify low-risk patients with T2DM who can be assigned biennial or triennial screening intervals.

From randomised controlled trials to real-world data: Clinical evidence to guide management of diabetic macular oedema

Randomised clinical trials (RCTs) are generally considered the gold-standard for providing scientific evidence for treatments' effectiveness and safety but their findings may not always be generalisable to the broader population treated in routine clinical practice. RCTs include highly selected patient populations that fit specific inclusion and exclusion criteria. Although they may have a lower level of certainty than RCTs on the evidence hierarchy, real-world data (RWD), such as observational studies, registries and databases, provide real-world evidence (RWE) that can complement RCTs. For example, RWE may help satisfy requirements for a new indication of an already approved drug and help us better understand long-term treatment effectiveness, safety and patterns of use in clinical practice. Many countries have set up registries, observational studies and databases containing information on patients with retinal diseases, such as diabetic macular oedema (DMO). These DMO RWD have produced significant clinical evidence in the past decade that has changed the management of DMO. RWD and medico-administrative databases are a useful resource to identify low frequency safety signals. They often have long-term follow-up with a large number of patients and minimal exclusion criteria. We will discuss improvements in healthcare information exchange technologies, such as blockchain technology and FHIR (Fast Healthcare Interoperability Resources), which will connect and extend databases already available. These registries can be linked with existing or emerging retinal imaging modalities using artificial intelligence to aid diagnosis, treatment decisions and provide prognostic information. The results of RCTs and RWE are combined to provide evidence-based guidelines.

Five-Year Incidence of Proliferative Diabetic Retinopathy and Associated Risk Factors in a Nationwide Cohort of 201 945 Danish Patients with Diabetes

Purpose

To evaluate the proliferative diabetic retinopathy (PDR) progression rates and identify the demographic and clinical characteristics of patients who later developed PDR compared with patients who did not progress to that state.

Design

A national 5-year register-based cohort study including 201 945 patients with diabetes.

Subjects

Patients with diabetes who had attended the Danish national screening program (2013-2018) for diabetic retinopathy (DR).

Methods

We used the first screening episode as the index date and included both eyes of patients with and without subsequent progression of PDR. Data were linked with various national health registries to investigate relevant clinical and demographic parameters. The International Clinical Retinopathy Disease Scale was used to classify DR, with no DR as level 0, mild DR as level 1, moderate DR as level 2, severe DR as level 3, and PDR as level 4.

Main Outcome Measures

Hazard ratios (HRs) for incident PDR for all relevant demographic and clinical parameters and 1-, 3-, and 5-year incidence rates of PDR according to baseline DR level.

Results

Progression to PDR within 5 years was identified in 2384 eyes of 1780 patients. Proliferative diabetic retinopathy progression rates from baseline DR level 3 at 1, 3 and 5 years were 3.6%, 10.9%, and 14.7%, respectively. The median number of visits was 3 (interquartile range, 1-4). Progression to PDR was predicted in a multivariable model by duration of diabetes (HR, 4.66 per 10 years; 95% confidence interval [CI], 4.05-5.37), type 1 diabetes (HR, 9.61; 95% CI, 8.01-11.53), a Charlson Comorbidity Index score of > 0 (score 1: HR, 4.62; 95% CI, 4.14-5.15; score 2: HR, 2.28; 95% CI, 1.90-2.74; score ≥ 3: HR, 4.28; 95% CI, 3.54-5.17), use of insulin (HR, 5.33; 95% CI, 4.49-6.33), and use of antihypertensive medications (HR, 2.23; 95% CI, 1.90-2.61).

Conclusions

In a 5-year longitudinal study of an entire screening nation, we found increased risk of PDR with increasing baseline DR levels, longer duration of diabetes, type 1 diabetes, systemic comorbidity, use of insulin, and blood pressure-lowering medications. Most interestingly, we found lower risk of progression from DR level 3 to PDR compared with that in previous studies.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Fructosamine as a predictor of incident diabetic microvascular disease in a population with high prevalence of red cell disorders: A cohort study

AIMS

Fructosamine can be used to estimate glycaemia in individuals in whom HbA1c may be unreliable. We aimed to establish clinically useful fructosamine treatment targets in a population with a high prevalence of conditions affecting erythrocyte survival, including variant haemoglobin and G6PD deficiency.

METHODS

Fructosamine was measured on a clinical basis in individuals in whom HbA1c was suspected to be unreliable by their primary physician. Study endpoints were incident retinopathy and albuminuria in individuals with Prediabetes (n = 60), Type 1 (n = 161) or Type 2 diabetes (n = 1350) during follow up of 4.4 ± 2.3 years.

RESULTS

Fructosamine ≥ 250 umol/L was significantly associated with incident retinopathy, and fructosamine ≥ 300 umol/L with incident microalbuminuria, in univariate analysis and adjusted for established risk factors. Fructosamine ≥ 250 umol/L was also significantly associated with incident retinopathy in individuals with HbA1c < 7.0% (53 mmol/mol) at inclusion.

CONCLUSIONS

In this patient population, a single measurement of fructosamine significantly and independently predicts incident retinopathy in individuals with HbA1c < 7.0% (53 mmol/mol). Routine measurement of fructosamine on at least one occasion is recommended as part of assessment of prediabetes or diabetes mellitus in populations with a high prevalence of conditions affecting erythrocyte lifespan.

Intraretinal Microvascular Abnormalities and Venous Beading Have Different Genetic Profiles in Caucasian Patients with Non-Proliferative Diabetic Retinopathy

Diabetic Retinopathy (DR) is a leading cause of preventable visual impairment in the working age population. Despite the increasing prevalence of DR, there remain gaps in our understanding of its pathophysiology. This is a prospective case-control study comparing the genetic profiles of patients with no DR vs. non-proliferative DR (NPDR) focusing on intraretinal microvascular abnormalities (IRMA) and venous beading (VB) in Caucasians. A total of 596 participants were recruited to the study; 199 with moderate/severe NPDR and 397 with diabetes for at least 5 years without DR. Sixty-four patients were excluded due to technical issues. In total, 532 were analysed; 181 and 351 were in the NPDR group and no DR group, respectively. Those with severe IRMA and VB had distinctly different genetic profiles from each other and from the no DR group, which further supports the theory that these two features of DR might have different etiologies. This also suggests that IRMA and VB are independent risk factors for the development of PDR and may have different pathophysiologies. If these findings are confirmed in larger studies, this could pave the way for personalised treatment options for those more at risk of developing different features of NPDR.

Analysis of independent risk factors for progression of different degrees of diabetic retinopathy as well as non-diabetic retinopathy among type 2 diabetic patients

Purpose

To study the independent risk factors for development of different degrees of diabetic retinopathy (DR) as well as non-DR (NDR) among type 2 diabetic patients.

Methods

This cross-sectional study included 218 patients with type 2 diabetes between January 2022 and June 2022. All the patients were divided into two groups: the DR group and the NDR group. The DR group was subdivided into the mild, moderate and severe non-proliferative DR (NPDR) group and the proliferative DR (PDR) group. Data recorded for all patients included age, gender, duration of diabetes, blood pressure, glycated hemoglobin (HbA1c), fasting blood glucose (FBG), blood lipids, best corrected visual acuity (BCVA), intraocular pressure (IOP), axial length (AL), anterior chamber depth (ACD), and renal function. Logistic regression methods were used to analyze the risk factors for DR.

Results

The prevalence of DR in type 2 diabetes was 28.44%. The duration of diabetes, age, mean arterial pressure (MAP), HbA1c, FBG, urinary albumin/creatinine ratio (UACR), BCVA, AL, and ACD were significantly different between the DR and the NDR groups (p < 0.05). Multivariate logistic regression analysis identified age, FBG, UACR, and AL as the independent risk factors for DR (OR = 0.843, 2.376, 1.049, 0.005; p = 0.034, 0.014, 0.016, p < 0.001).

Conclusion

Young age, short AL, higher levels of FBG and UACR were the independent risk factors for the progression of DR in type 2 diabetes.

Epidemiology of Treated Diabetes Ocular Complications in France 2008-2018-The LANDSCAPE French Nationwide Study

AIM

LANDSCAPE aimed to estimate the annual incidence and prevalence of treated diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) between 2008 and 2018.

METHODS

This French nationwide observational study used data from the French National Health Insurance Databases covering 99% of the French population. Data about healthcare consumption were used to identify adults treated with anti-VEGFs or dexamethasone implants (for DME) and with pan-retinal photocoagulation (for PDR). All French patients newly treated between 2008 and 2018 were included. Incidence and prevalence of treated DME and PDR were estimated for the age-matched general population and the population with diabetes in France. Sociodemographic characteristics and medical history were described in both populations.

RESULTS

We identified 53,584 treated DME patients and 127,273 treated PDR patients between 2008 and 2018, and 11,901 DME and 11,996 PDR new incident patients in 2018. The treated DME incidence in 2018 was 2.5 per 10,000 in the general population and 37.3 per 10,000 in the population with diabetes. Prevalence in 2018 was 9.5 and 143.7 per 10,000 in the respective populations. Treated PDR incidence in 2018 was 2.3 per 10,000 in the general population and 31.2 per 10,000 in the population with diabetes. Prevalence in 2018 was 19.9 and 270.3 per 10,000 in the respective populations. Incidence and prevalence were not age-dependent. Incidence of treated PDR incidence was relatively stable from 2008-2018. Incidence of treated DME incidence rose from 2012-2018, probably due to widening access to newly available treatments, such as anti-VEGFs.

CONCLUSIONS

We provide exhaustive nationwide data on the incidence and prevalence of treated diabetic ocular complications in France over a 10-year period.

Prevalence and incidence of diabetic retinopathy (DR) in the UK population of Gloucestershire

Purpose

To estimate prevalence and incidence of diabetic retinopathy (DR) in a UK region by severity between 2012 and 2016 and risk factors for progression to proliferative DR (PDR).

Methods

Electronic medical records from people with diabetes (PWD) ≥18 years seen at the Gloucestershire Diabetic Eye Screening Programme (GDESP) and the hospital eye clinic were analysed (HEC). Prevalence and incidence of DR per 100 PWD (%) by calendar year, grade and diabetes type were estimated using log‐linear regression. Progression to PDR and associated risk factors were estimated using parametric survival analyses.

Results

Across the study period, 35 873 PWD had at least one DR assessment. They were aged 66 (56–75) years (median (interquartile range)), 57% male, 5 (1–10) years since diabetes diagnosis, 93% Type 2 diabetes. Prevalence of DR decreased from 38.9% (95% CI: 38.1%, 39.8%) in 2012 to 36.6% (95% CI: 35.9%, 37.3%) in 2016 (p < 0.001). Incidence of any DR decreased from 10.9% (95% CI: 10.4%, 11.5%) in 2013 to 8.5% (95% CI: 8.1%, 9.0%) in 2016 (p < 0.001). Prevalence of PDR decreased from 3.5% (95% CI: 3.3%, 3.8%) in 2012 to 3.1% (95% CI 2.9%, 3.3%) in 2016 (p = 0.008). Incidence of PDR did not change over time. HbA_1c and bilateral moderate–severe NPDR were statistically significant risk factors associated with progression to PDR.

Conclusions

Incidence and prevalence of DR decreased between 2012 and 2016 in this well‐characterized population of the UK.

Diabetic Retinopathy and Insulin Insufficiency: Beta Cell Replacement as a Strategy to Prevent Blindness

Diabetic retinopathy (DR) is a potentially devastating complication of diabetes because it puts patients at risk of blindness. Diabetes is a common cause of blindness in the U.S. and worldwide and is dramatically increasing in global prevalence. Thus new approaches are needed to prevent this dreaded complication. There is extensive data that indicates beta cell secretory failure is a risk factor for DR, independent of its influence on glycemic control. This perspective article will provide evidence for insufficient endogenous insulin secretion as an important factor in the development of DR. The areas of evidence discussed are: (a) Presence of insulin receptors in the retina, (b) Clinical studies that show an association of beta cell insufficiency with DR, (c) Treatment with insulin in type 2 diabetes, a marker for endogenous insulin deficiency, is an independent risk factor for DR, (d) Recent clinical studies that link DR with an insulin deficient form of type 2 diabetes, and (e) Beta cell replacement studies that demonstrate endogenous insulin prevents progression of DR. The cumulative data drive our conclusion that beta cell replacement will have an important role in preventing DR and/or mitigating its severity in both type 1 diabetes and insulinopenic type 2 diabetes.

Risk Factors for Progression to Referable Diabetic Eye Disease in People With Diabetes Mellitus in Auckland, New Zealand: A 12-Year Retrospective Cohort Analysis

PURPOSE

To evaluate the prevalence and risk factors for the development of any and referable diabetic eye disease in a multi-ethnic New Zealand population with diabetes mellitus attending a regional retinal screening service.

METHODS

Retrospective observational cohort study of people living with diabetes who attended the Auckland Regional Diabetic Retinal Screening Programme 2006-2018 inclusive (n = 41,786).

RESULTS

Any retinopathy/maculopathy was present at first screening for 48.2% [95% confidence interval (CI): 45.8%-50.6%] / 37.8% (95% CI: 35.5%- 40.1%) of people with Type 1 and 25% (95% CI: 24.6%-25.4%) / 21.9% (95% CI: 21.5%-22.3%) with Type 2 diabetes. Referable retinopathy at baseline screening was 4.4% (95% CI: 3.6%-5.3%) and 1.6% (95% CI: 1.5%-1.7%) among people with Type 1 and Type 2 diabetes mellitus, respectively. After 4 years, cumulative incidence for referable retinopathy /referable maculopathy was 12/36 per 1000 people with Type 1 and 2.4/16 per 1000 people with Type 2 diabetes. Independent hazards for disease progression varied for the diabetes cohort types but baseline grade, duration of diabetes, and HbA1c were common to all.

CONCLUSIONS

Referable diabetic eye disease at the first screening and after 4 years of follow-up is uncommon. Lengthening of the screening intervals for people with no or mild diabetic eye disease at first screening assessment could be considered.

Association of the Monocyte-to-High-Density Lipoprotein Cholesterol Ratio With Diabetic Retinopathy

Background: Chronic inflammation in type 2 diabetes mellitus (T2DM) is an essential contributor to the development of diabetic retinopathy (DR). The monocyte–to–high-density lipoprotein cholesterol (HDL-C) ratio (MHR) is a novel and simple measure related to inflammatory and oxidative stress status. However, little is known regarding the role of the MHR in evaluating the development of DR.

Methods: A total of 771 patients with T2DM and 607 healthy controls were enrolled in this cross-sectional study. MHR determination and eye examination were performed. The association of MHR with the prevalence of DR in T2DM patients was analyzed.

Results: The MHR in patients with DR was significantly higher than that in both non-DR diabetic patients (P < 0.05) and healthy controls (P < 0.01). No significance was observed in the MHR of different DR severity grades. Moreover, the MHR was similar between patients with non-macular oedema and those with macular oedema. Logistic regression analysis demonstrated that MHR was independently associated with the prevalence of DR in diabetic patients [odds ratio (OR) = 1.438, 95% confidence interval (CI): 1.249–1.655, P < 0.01]. After additional stratification by HbA1c level and diabetic duration, the MHR was still independently associated with the prevalence of DR.

Conclusions: Our study suggests that the MHR can be used as a marker to indicate the prevalence of DR in patients with T2DM.

Incidence of sight-threatening diabetic retinopathy in an established urban screening programme: An 11-year cohort study

AIMS

Systematic annual screening to detect sight-threatening diabetic retinopathy (STDR) is established in the United Kingdom. We designed an observational cohort study to provide up-to-date data for policy makers and clinical researchers on incidence of key screening endpoints in people with diabetes attending one screening programme running for over 30 years.

METHODS

All people with diabetes aged ≥12 years registered with general practices in the Liverpool health district were offered inclusion. Data sources comprised: primary care (demographics, systemic risk factors), Liverpool Diabetes Eye Screening Programme (retinopathy grading), Hospital Eye Services (slit lamp biomicroscopy assessment of screen positives).

RESULTS

133,366 screening episodes occurred in 28,384 people over 11 years. Overall incidences were: screen positive 6.7% (95% CI 6.5-6.8), screen positive for retinopathy 3.1% (3.0-3.1), unassessable images 2.6% (2.5-2.7), other significant eye diseases 1.0% (1.0-1.1). 1.6% (1.6-1.7) had sight-threatening retinopathy confirmed by slit lamp biomicroscopy. The annual incidence of screen positive and screen positive for retinopathy showed consistent declines from 8.8%-10.6% and 4.4%-4.6% in 2007/09 to 4.4%-6.8% and 2.3%-2.9% in 2013/17, respectively. Rates of STDR (true positive) were consistently below 2% after 2008/09. Screen positive rates were higher in first time attenders (9.9% [9.4-10.2] vs. 6.1% [6.0-6.2]) in part due to ungradeable images (4.1% vs. 2.3%) and other eye disease (2.4% vs. 0.8%). 4.5% (3.9-5.2) of previous non-attenders had sight-threatening retinopathy. Compared with people with type 2 diabetes, those with type 1 disease demonstrated higher rates of screen positive (11.9% vs. 6.0%) and STDR (6.4% vs. 1.2%). Overall prevalence of any retinopathy was 27.2% (27.0-27.4).

CONCLUSIONS

In an established screening programme with a stable population screen, positive rates show a consistent fall over time to a low level. Of those who are screen positive, fewer than 50% are screen positive for diabetic retinopathy. Most are due to sight threatening maculopathy. The annual incidence of STDR is under 2% suggesting future work on redefining screen positive and supporting extended intervals for people at low risk. Higher rates of screen positive and STDR are seen in first time attenders. Those who have never attended for screening should be specifically targeted.

Characteristics of repeat non-attenders at Diabetes Eye Screening Wales, a national community-based diabetes-related retinopathy screening service, during 2003-2018

AIMS

To understand factors associated with repeat non-attendance at screening for diabetes-related retinopathy.

METHODS

Retrospective observational study using anonymised data from Diabetic Eye Screening Wales for people with a full history of screening invitations and attendances was linked with primary and secondary care records held in the Secure Anonymised Information Linkage Databank. Repeat non-attendance was defined as no record of attendance during any 36-month period despite three cycles of annual screening invitations. The associations between repeat non-attendance and potential risk factors were examined using multivariable logistic regression analysis, stratified according to type 1 and type 2 diabetes.

RESULTS

A total of 18% with type 1 diabetes (1146/6513) and 8% with type 2 diabetes (12,475/156,525) were repeat non-attenders. Participants attending their very first appointment were least likely to become repeat non-attenders [odds ratio (95% confidence interval)]: type 1 diabetes: 0.12 (0.09, 0.17) and type 2 diabetes: 0.08 (0.07, 0.09). For both types of diabetes, those of a younger age, living in areas of higher deprivation and subject to multiple house moves were at greater risk of becoming repeat non-attenders.

CONCLUSION/INTERPRETATION

A more tailored approach is needed for the younger population, those living in areas of higher deprivation and/or undergoing multiple residential relocation and to ensure attendance at their initial appointment to minimise future repeat non-attendance.

Declined incidence of patients treated for vision-threatening diabetic retinopathy in South Korea: a 12-year nationwide population-based study

PURPOSE

To determine the age- and sex-specific annual incidence rates of patients treated for VTDR and the factors associated with increased treatment rates in patients with type 2 diabetes mellitus (T2DM) in South Korea.

METHODS

This was a nationwide, retrospective, 12-year, population-based study. Patients aged over 30 years who were diagnosed with T2DM between 2006 and 2017 were included in this study. We evaluated the national health claims data acquired from the Korean National Health Insurance Service database. Main outcome measures were the annual incidence rates of patients treated for VTDR and the associated risk factors.

RESULTS

The age-adjusted annual incidence rate of patients treated for VTDR significantly decreased from 10.05 per 1000 T2DM patients in 2006 to 6.11 in 2017 (β =  - 0.3192, P < 0.0001). The sex-adjusted annual incidence rate also significantly decreased in both men (β =  - 0.2861, P < 0.0001) and women (β =  - 0.3666, P < 0.0001). Cox hazard analysis showed that factors such as insulin use, young age, chronic kidney disease and male sex were significantly associated with increased rate of treatments for VTDR. In addition, the risk was lower for rural than for metropolitan residents.

CONCLUSIONS

Despite the increase in the number of T2DM patients in South Korea, the incidence rate of patients treated for VTDR decreases with early diagnosis and appropriate treatment. Therefore, it is important to detect and manage high-risk groups early to prevent visual impairment due to VTDR.

Disease burden of diabetes, diabetic retinopathy and their future projections in the UK: cross-sectional analyses of a primary care database

OBJECTIVES

To estimate the current disease burden, trends and future projections for diabetes mellitus (DM) and diabetic retinopathy (DR) in the IQVIA Medical Research Data (IMRD).

PARTICIPANTS/DESIGN/SETTING

We performed a cross-sectional study of patients aged 12 and above to determine the prevalence of DM and DR from the IMRD database (primary care database) in January 2017, involving a total population of 1 80 824 patients with DM. We also carried out a series of cross-sectional studies to investigate prevalence trends, and then applied a double exponential smoothing model to forecast the future burden of DM and DR in the UK.

RESULTS

The crude DM prevalence in 2017 was 5.2%. The DR, sight-threatening retinopathy (STR) and diabetic maculopathy prevalence figures in 2017 were 33.78%, 12.28% and 7.86%, respectively, in our IMRD cross-sectional study. There were upward trends in the prevalence of DM, DR and STR, most marked and accelerating in STR in type 1 DM but slowing in type 2 DM, and in the overall prevalence of DR.

CONCLUSION

Our results suggest differential rising trends in the prevalence of DM and DR. Preventive strategies, as well as treatment services planning, can be based on these projected prevalence estimates. Improvements that are necessary for the optimisation of care pathways, and preparations to meet demand and capacity challenges, can also be based on this information. The limitations of the study can be overcome by a future collaborative study linking DR screening and hospital eye services data.

Progress of artificial intelligence in diabetic retinopathy screening

Diabetic retinopathy (DR) is one of the leading causes of blindness worldwide, and the limited availability of qualified ophthalmologists restricts its early diagnosis. For the past few years, artificial intelligence technology has developed rapidly and has been applied in DR screening. The upcoming technology provides support on DR screening and improves the identification of DR lesions with a high sensitivity and specificity. This review aims to summarize the progress on automatic detection and classification models for the diagnosis of DR.

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

AIMS

We 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.

METHODS

In 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.

RESULTS

All 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.

CONCLUSIONS

This 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.

[Interdisciplinary communication: ophthalmologists' letters to practices specializing in diabetic patients]

BACKGROUND

Ophthalmologists' letters and medical reports play an important role in the interdisciplinary cooperation between general practitioner, internist, diabetologist and ophthalmologist providing means of information and communication for the avoidance, delay and treatment of diabetic retinopathy (DR).

METHODS

In a cross-sectional study (NCT02311504) the ophthalmologicsts' letters and other clinical parameters were extracted from electronic patient records (EPR) of 810 patients with diabetes. Files were classified into different categories of formats, tested with respect to topicality and content structure and analyzed according to the topic complex of the national treatment guidelines for retinal complications.

RESULTS

In 59% of the patients an ophthalmologist's medical report was identified in the EPR. Of these, 26% were computer-generated documents, 73% were handwritten. 55% used the standard form of the national guidelines, 21% were self-designed formats, 16% detailed letters, 5% short reports and 3% short messages. The information was written on average 19 months ago. Of the documents 25% were older than 2 years at the time of the study. Of the patients 75% visited an ophthalmologist in the previous 12 months, yielding a report rate of only 40%. The prevalence of DR reported in the forms was 12%, in detailed letters 32%.

CONCLUSION

Although standardized forms are widely distributed in the ophthalmologists' communication with diabetologists, there is room for improvement in the face of the low report rate to enable a timely consideration of relevant findings. The high number of handwritten documents shows the large untapped potential of electronic formats in the interdisciplinary communication.

Epidemiology of moderately severe and severe non-proliferative diabetic retinopathy in South West England

Aims

To estimate the incidence of early treatment diabetic retinopathy study (ETDRS) level 47 and 53 and progression to treatment with panretinal photocoagulation (PRP) for proliferative DR (PDR).

Methods

Log-linear regression was used to estimate the incidence of level 47–53 or worse for 33,009 people with diabetes (PWD) in Gloucestershire during 2013–2016 by calendar year and diabetes type, based on the first recording. Progression was analysed in Gloucestershire and Bristol with a parametric survival analysis examining the association of baseline and time-varying demographic and clinical factors on time to PRP after the first recording of level 47–53.

Results

Incidence decreased from 0.57 (95% confidence intervals (CI) 0.48–0.67) per 100 PWD in 2013 to 0.35 (95% CI 0.29–0.43) in 2016 (p < 0.001). For progression, 338 eligible PWD from Gloucestershire and 418 from Bristol were followed for a median of 1.4 years; 78 and 83% had Type 2 diabetes and a median (interquartile range) of 15 (10–22) and 17 (11–25) years duration of diagnosed diabetes respectively. Three years from the incident ETDRS 47–53, 18.9% and 17.2% had received PRP respectively. For Gloucestershire, severe IRMA and updated mean HbA_1c were associated with an increase in the risk of initiating PRP (hazard ratio 3.14 (95% CI: 1.60–6.15) and 1.21 (95% CI: 1.06–1.38 per 10 mmol/mol) respectively).

Conclusion

This study provides additional understanding of this population and shows that a high proportion of patients with ETDRS levels 47–53 need to be monitored as they are at high risk of progressing to PDR.

Screening for Diabetic Retinopathy with Extended Intervals, Safe and Without Compromising Adherence: A Retrospective Cohort Study

INTRODUCTION

Screening for diabetic retinopathy (DR) prevents blindness through the early detection of sight-threatening retinal microvascular lesions that respond to timely local treatment. However, the provision of easy and regular access to DR screening programs is currently being challenged by the increasing prevalence of diabetes. One proposed solution is to extend the screening interval for patients at low risk for progression of retinopathy. To date, most providers of screening programs have hesitated to implement a strategy of extended intervals due to the lack of data on whether adherence and safety are compromised when retinal examinations occur less frequently. In the study reported here, we investigated adherence to the screening program and progression of retinopathy in patients with type 2 diabetes participating in a DR screening program with extended intervals.

METHODS

This was a retrospective study that included 1000 patients with type 2 diabetes mellitus who attended a screening program for DR. The patients were consecutively placed into a low-risk patient cohort with no retinopathy or into an intermediate-risk patient cohort with mild retinopathy (each cohort n = 500). Screening intervals were 36 months for the low-risk cohort and 18 months for the intermediate-risk cohort.

RESULTS

The 1000 subjects enrolled in the study had a median age of 68 (interquartile range 12) years and 60.4% were men. At the follow-up screening visit, data on 102 subjects were not included in the analysis of adherence rate due to death, severe systemic illness, other concurrent eye disease or migration. Among the 898 remaining subjects, adherence to the screening program was 93.7% (413/443) in the 36-month group and 98.3% (449/455) in the 18-month group (p < 0.0001). Non-adherence decreased with increasing age (odds ratio 0.92, 95% confidence interval 0.888-0.954, p = 0.0005). At follow-up, 65 subjects showed progression of retinopathy; none had worse than moderate retinopathy. Risk factors for DR and treatment for hyperglycemia, hypertension and hyperlipidemia were compared among subjects in the low-risk cohort: non-adherent subjects did not differ from their adherent counterparts without progression of DR, but the former had a shorter duration of diabetes and higher diastolic blood pressure than adherent subjects with progression of DR (4.5 vs. 7.5 years, p = 0.007; and 80 vs. 75 mmHg, p = 0.02, respectively).

CONCLUSION

The results suggest that screening DR at extended intervals can be achieved with high adherence rates without compromising patient safety. However, younger subjects and those at higher risk of progression may require extra attention.

Cost-effectiveness of biennial screening for diabetes related retinopathy in people with type 1 and type 2 diabetes compared to annual screening

OBJECTIVE

Examine the health and economic impact of extending screening intervals in people with Type 2 diabetes (T2DM) and Type 1 diabetes (T1DM) without diabetes-related retinopathy (DR).

SETTING

Diabetic Eye Screening Wales (DESW).

STUDY DESIGN

Retrospective observational study with cost-utility analysis (CUA) and Decremental Cost-Effectiveness Ratios (DCER) study.

INTERVENTION

Biennial screening versus usual care (annual screening).

INPUTS

Anonymised data from DESW were linked to primary care data for people with two prior screening events with no DR. Transition probabilities for progression to DR were estimated based on a subset of 26,812 and 1232 people with T2DM and T1DM, respectively. DCER above £20,000 per QALY was considered cost-effective.

RESULTS

The base case analysis DCER results of £71,243 and £23,446 per QALY for T2DM and T1DM respectively at a 3.5% discount rate and £56,822 and £14,221 respectively when discounted at 1.5%. Diabetes management represented by the mean HbA_1c was 7.5% for those with T2DM and 8.7% for T1DM.

SENSITIVITY ANALYSIS

Extending screening to biennial based on HbA_1c, being the strongest predictor of progression of DR, at three levels of HbA_1c 6.5%, 8.0% and 9.5% lost one QALY saving the NHS £106,075; £58,653 and £31,626 respectively for T2DM and £94,696, £37,646 and £11,089 respectively for T1DM. In addition, extending screening to biennial based on the duration of diabetes > 6 years for T2DM per QALY lost, saving the NHS £54,106 and for 6-12 and > 12 years for T1DM saving £83,856, £23,446 and £13,340 respectively.

CONCLUSIONS

Base case and sensitivity analyses indicate biennial screening to be cost-effective for T2DM irrespective of HbA_1c and duration of diabetes. However, the uncertainty around the DCER indicates that annual screening should be maintained for those with T1DM especially when the HbA_1c exceeds 80 mmol/mol (9.5%) and duration of diabetes is greater than 12 years.

Burden of disease and costs associated with type 2 diabetes in emerging and established markets: systematic review analyses

Objectives: To estimate the clinical and economic burden of type 2 diabetes (T2D) in established (EST) and emerging markets (EMG).Methods: Three systematic literature reviews were conducted in MEDLINE and Embase to capture all relevant publications reporting 1) the epidemiology of T2D and complications in T2D and 2) the economic burden of T2D and associated complications.Results: In total, 294 studies were included in this analysis. Evidence indicates a high and increasing overall prevalence of T2D globally, ranging up to 23% in EMG markets and 14% in EST markets. Undiagnosed cases were higher in EMG versus EST markets (up to 67% vs 38%), potentially due to a lack of education and disease awareness in certain regions, that could lead to important clinical and economic consequences. Poor glycemic control was associated with the development of several complications (e.g. retinopathy, cardiovascular diseases and nephropathy) that increase the risk of morbidity and mortality. Direct costs were up to 9-fold higher in patients with vs without T2D-related complications.Conclusions: The burden of T2D, related complications and inherent costs are higher in emerging versus established market countries. This review explores potential strategies to reduce costs and enhance outcomes of T2D treatment in developing countries.

Ten-year incidence and assessment of safe screening intervals for diabetic retinopathy: the OPHDIAT study

BACKGROUND

To estimate the 10-year incidence of referable diabetic retinopathy (DR) in a French population with type 1 and 2 diabetes mellitus (DM). A secondary objective was the assessment of safe screening intervals in patients with diabetes without retinopathy.

METHODS

Observational, prospective and multicentric study between June 2004 and September 2017 based on a regional screening programme for DR in the Paris region. The incidence of referable DR in patients without retinopathy at baseline was calculated by the Turnbull survival estimator. A safe screening interval was defined as a 95% probability of remaining without referable DR.

RESULTS

Among the 25 745 participants with type 1 (n=6086) or type 2 (n=19 659) DM, the 10-year cumulative incidence of referable DR was 19.10% (95% CI 17.21% to 21.14%) and 17.03% (15.78% to 18.35%), median (IQR) follow-up=3.33 (4.24) years. The safe screening interval for patients without DR at the first examination for type 1 and 2 DM was 2.2 (95% CI 2.0 to 2.4) and 3.0 (2.9 to 3.1) years, respectively. In a subgroup of low-risk patients with type 2 DM, the safe screening interval was 4.2 (3.8 to 4.6) years.

CONCLUSIONS

These data suggest that in Paris area, a 2-year, 3-year and 4-year screening interval was considered safe for type 1 DM, type 2 DM and for low-risk patients with type 2 DM, respectively, without DR at the first examination. While these data might be used to support the consideration of extending screening intervals, a randomised clinical trial would be suitable to confirm the safety for patients with DM.

Trends in Diabetic Retinopathy, Visual Acuity, and Treatment Outcomes for Patients Living With Diabetes in a Fundus Photograph-Based Diabetic Retinopathy Screening Program in Bangladesh

IMPORTANCE

Diabetic retinopathy (DR) is the leading cause of low vision among working-age adults. An estimated 6.9 million people in Bangladesh were living with diabetes in 2017, which is projected to increase to more than 10 million people in 2025. Currently, no standardized and/or large-scale DR screening program exists in Bangladesh.

OBJECTIVE

To develop a novel fundus photograph-based eye screening model for early detection of DR to prevent vision loss in Bangladeshi individuals with diabetes.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, 49 264 patients with diabetes underwent opportunistic eye screening at 2 eye hospitals and 1 diabetic hospital in Bangladesh between June 1, 2010, and September 30, 2017. The data set was analyzed from April 8 to December 30, 2018. Technicians were trained to obtain 2-field digital fundus photographs and to grade each according to a standardized DR severity scale. Each patient was counseled and triaged for treatment using defined DR referral criteria.

MAIN OUTCOMES AND MEASURES

Primary DR grading outcomes, visual acuity, and treatment outcomes.

RESULTS

A total of 49 264 patients (54.3% male; mean [SD] age, 50.8 [12.3] years) underwent DR screening during a 7-year period. The DR prevalence rate across all 3 sites was 33% (95% CI, 33%-33%). Prevalence rates varied by center (Chittagong, 64.6% [95% CI, 64.0%-65.0%]; Dhaka, 39.8% [95% CI, 39.0%-41.0%]; and Feni, 13.0% [95% CI, 13.0%-14.0%]). Across all age groups, male patients were at higher risk of prevalent DR than female patients (odds ratio, 1.99; 95% CI, 1.90-2.07). The prevalence was 3.9% for preproliferative DR, 7.8% for proliferative DR, and 19.2% for maculopathy. Individuals with DR had significantly worse visual acuity than those with no DR (best-corrected visual acuity, 0.35 vs 0.21 logMAR; P < .001). The rate of moderate visual impairment was 12.2%, and the rate of blindness was 2.5%. Primary treatments included laser photocoagulation (n = 1637), intravitreal injection (n = 1440), and vitrectomy (n = 309).

CONCLUSIONS AND RELEVANCE

Screening Bangladeshi individuals known to have diabetes using fundus photography identified large numbers of patients with sight-threatening proliferative DR, maculopathy, and visual impairment or blindness. Expansion of eye screening services in Bangladesh is warranted as part of a national government eye care and diabetes health policy.

IDF Diabetes Atlas: A review of studies utilising retinal photography on the global prevalence of diabetes related retinopathy between 2015 and 2018

AIMS

The purpose of this study is to assess the prevalence of diabetic retinopathy (DR) world-wide from articles published since 2015 where the assessment of the presence and severity of DR was based on retinal images.

METHODS

A total of 4 databases were searched for the MESH terms diabetic retinopathy and prevalence. Of 112 publications 32 studies were included and individual data pooled for analysis. The presence of any DR or diabetic macular edema (DME) was recorded and severity as mild, moderate or severe non-proliferative DR (NPDR), proliferative DR (PDR) and DME and/or clinically significant macular edema (CSME). The level of severity of DR reported refer to persons with diabetes and not individual eyes.

RESULTS

The global prevalence of DR and DME, for the period 2015 to 2019 were 27.0% for any DR comprising of 25.2%, NPDR, 1.4% PDR and 4.6% DME. The lowest prevalence was in Europe at 20.6% and South East Asia at 12.5% and highest in Africa at 33.8%, Middle East and North Africa 33.8%, and the Western Pacific region at 36.2%.

CONCLUSIONS

This study illustrated difficulties in deriving a meaningful global prevalence rate for DR and DME due to the lack of uniformity in defining the study populations, methodological differences, retinal image capture and grading criteria. Therefore, international consensus is required using a minimal data set for future studies.

Incidence of sight-threatening diabetic retinopathy in people with Type 2 diabetes mellitus and numbers needed to screen: a systematic review

AIM

To investigate the incidence of sight-threatening diabetic retinopathy in Type 2 diabetes mellitus.

BACKGROUND

In most countries, yearly or biennial screening intervals for diabetic retinopathy in people with Type 2 diabetes are recommended. Fewer screening sessions reduce the effort required of people with Type 2 diabetes and reduce healthcare costs.

METHODS

We conducted a search of PubMed, Embase, Web of Science and the COCHRANE Library for studies published betweeen 1 January 2000 and 1 January 2017. Eligible studies were those that included general populations of >100 people with Type 2 diabetes mellitus. Additional study population criteria were absence of moderate diabetic retinopathy or more severe diabetic retinopathy at last screening session and at least two gradable retinal screening sessions. Outcomes of interest in the included studies were moderate and severe non-proliferative diabetic retinopathy (R2), proliferative diabetic retinopathy (R3) or maculopathy (M1), collectively known as sight-threatening or referable diabetic retinopathy.

RESULTS

A total of 17 studies were included. In people with Type 2 diabetes without or with only mild diabetic retinopathy at baseline, the average incidence rates of sight-threatening diabetic retinopathy were ~1 per 100 person-years and ~8 per 100 person-years, respectively. The average numbers needed to screen to detect one case of sight-threatening diabetic retinopathy were 175 and 19 in people without and with mild retinopathy at last screening, respectively.

CONCLUSION

In people with Type 2 diabetes without retinopathy at last screening, the incidence of severe sight-threatening retinopathy at the subsequent screening session was low. In people with mild retinopathy, progression to sight-threatening diabetic retinopathy was nearly 10-fold higher. This review supports lengthening of the screening interval of patients with Type 2 diabetes without retinopathy at last screening session.

Prevalence, incidence and future projection of diabetic eye disease in Europe: a systematic review and meta-analysis

To examine the prevalence and incidence of diabetic eye disease (DED) among individuals with diabetes in Europe, a systematic review to identify all published European prevalence and incidence studies of DED in individuals with diabetes managed in primary health care was performed according to the MOOSE and PRISMA guidelines. The databases Medline, Embase and Web of Science were searched to 2 September 2017. Meta-analyses and meta-regressions were performed. The pooled prevalence estimates were applied to diabetes prevalence rates provided by the International Diabetes Foundation atlas and Eurostat population data, and extrapolated to the year 2050. Data of 35 prevalence and four incidence studies were meta-analyzed. Any diabetic retinopathy (DR) and diabetic macular edema (DME) were prevalent in 25.7% (95% CI 22.8-28.8%) and 3.7% (95% CI 2.2-6.2%), respectively. In meta-regression, the prevalence of DR in persons with type 1 diabetes was significantly higher compared to persons with type 2 diabetes (54.4% vs. 25.0%). The pooled mean annual incidence of any DR and DME in in persons with type 2 diabetes was 4.6% (95% CI 2.3-8.8%) and 0.4% (95% CI 0.5-1.4%), respectively. We estimated that persons with diabetes affected by any DED in Europe will increase from 6.4 million today to 8.6 million in 2050, of whom 30% require close monitoring and/or treatment. DED is estimated to be present in more than a quarter of persons with type 2 diabetes and half of persons with type 1 diabetes underlining the importance of regular monitoring. Future health services need to be planned accordingly.

Retinopathy among Chinese subjects with type 2 diabetes mellitus in Shanghai: A community-based follow-up study

OBJECTIVE

To determine the incidence, progression, and regression rates of diabetic retinopathy (DR), as well as their associated factors, in Chinese type 2 diabetic patients.

METHODS

Diabetic patients who participated in a previous survey were recruited for a 1-year follow-up study. Nonmydriatic fundus photographs were acquired to assess the severity of DR as per the International Clinical Diabetic Retinopathy Disease Severity Scale (2002). Factors that potentially influence DR outcomes, including its incidence, progression, and regression, were identified via statistical analyses.

RESULTS

We initially recruited 2453 subjects, among whom 2331 were followed and included in the final analysis. The incidences of new and progressed (ie, ≥2 scale steps) DR were 10.6% and 6.1%, respectively. Moreover, 7.3% of patients with established DR at baseline experienced complete regression. Multivariate logistic regression analysis revealed that high glycosylated haemoglobin (HbA1c) (odds ratio [OR] = 1.50, P = .021) and hyperlipidaemia (OR = 1.46, P = .025) were independent predictors of DR development, high HbA1c (OR = 4.16, P = .027) and macroalbuminuria (OR = 5.60, P = .010) predicted DR progression, and low HbA1c (OR = 0.20, P = .001) and low triglyceride levels (OR = 0.34, P = .026) were associated with DR regression.

CONCLUSIONS

Albumin and HbA1c levels should be closely monitored as signs of progressive retinal damage in diabetic subjects. Optimized control of glucose and triglyceride levels is vital for reducing the incidence of DR or promoting its regression in afflicted patients.

Apocynin ameliorates diabetic retinopathy in rats: Involvement of TLR4/NF-κB signaling pathway

Diabetic retinopathy is a diabetes complication. During diabetic retinopathy development, the TLR4/NF-κB pathway is up-regulated. Apocynin is a nicotinamide adenine dinucleotide phosphate oxidase blocker which can reduce the superoxide radicals. It is demonstrated that apocynin can inhibit TLR4/NF-κB pathway in rats. We aim to figure out whether apocynin treatment is benefit for the diabetic retinopathy in rat model. The diabetes in rats was induced by streptozotocin. The treatment of apocynin (16 mg/kg/day) or vehicle in diabetic rat model was maintained for 12 weeks. The expression levels of relative genes in this research were shown through Western blot and qRT-PCR. Morphology of the retinas was shown by Hematoxylin-Eosin staining. The treatment of apocynin ameliorated biochemical indexes in diabetic rats and rescued the morphology of the retinas. After a 12 weeks apocynin treatment, the cell apoptosis, oxidative stress, and inflammatory in retina was reduced in diabetic rats. TLR4/NF-κB signaling pathway activity in diabetic rat retina was inhibited by apocynin. Based on our study, the treatment of apocynin ameliorates diabetic retinopathy in rats. The TLR4/NF-κB signaling pathway inhibition by apocynin is involved in this process. This result indicated a great therapeutic potential of apocynin in diabetic retinopathy treatment.

Label-free quantitation of glycated hemoglobin in single red blood cells by transient absorption microscopy and phasor analysis

As a stable and accurate biomarker, glycated hemoglobin (HbA1c) is clinically used to diagnose diabetes with a threshold of 6.5% among total hemoglobin (Hb). Current methods such as boronate affinity chromatography involve complex processing of large-volume blood samples. Moreover, these methods cannot measure HbA1c fraction at single-red blood cell (RBC) level, thus unable to separate the contribution from other factors such as RBC lifetime. Here, we demonstrate a spectroscopic transient absorption imaging approach that is able to differentiate HbA1c from Hb on the basis of their distinct excited-state dynamics. HbA1c fraction inside a single RBC is derived quantitatively through phasor analysis. HbA1c fraction distribution of diabetic blood is apparently different from that of healthy blood. A mathematical model is developed to derive the long-term blood glucose concentration. Our technology provides a unique way to study heme modification and to derive clinically important information void of bloodstream glucose fluctuation.

Deep learning in estimating prevalence and systemic risk factors for diabetic retinopathy: a multi-ethnic study

In any community, the key to understanding the burden of a specific condition is to conduct an epidemiological study. The deep learning system (DLS) recently showed promising diagnostic performance for diabetic retinopathy (DR). This study aims to use DLS as the grading tool, instead of human assessors, to determine the prevalence and the systemic cardiovascular risk factors for DR on fundus photographs, in patients with diabetes. This is a multi-ethnic (5 races), multi-site (8 datasets from Singapore, USA, Hong Kong, China and Australia), cross-sectional study involving 18,912 patients (n = 93,293 images). We compared these results and the time taken for DR assessment by DLS versus 17 human assessors - 10 retinal specialists/ophthalmologists and 7 professional graders). The estimation of DR prevalence between DLS and human assessors is comparable for any DR, referable DR and vision-threatening DR (VTDR) (Human assessors: 15.9, 6.5% and 4.1%; DLS: 16.1%, 6.4%, 3.7%). Both assessment methods identified similar risk factors (with comparable AUCs), including younger age, longer diabetes duration, increased HbA1c and systolic blood pressure, for any DR, referable DR and VTDR (p > 0.05). The total time taken for DLS to evaluate DR from 93,293 fundus photographs was ~1 month compared to 2 years for human assessors. In conclusion, the prevalence and systemic risk factors for DR in multi-ethnic population could be determined accurately using a DLS, in significantly less time than human assessors. This study highlights the potential use of AI for future epidemiology or clinical trials for DR grading in the global communities.

Diabetic retinopathy: a complex pathophysiology requiring novel therapeutic strategies

INTRODUCTION

Diabetic retinopathy (DR) is the leading cause of vision loss in the working age population of the developed world. DR encompasses a complex pathology, and one that is reflected in the variety of currently available treatments, which include laser photocoagulation, glucocorticoids, vitrectomy and agents which neutralize vascular endothelial growth factor (VEGF). Whilst these options demonstrate modest clinical benefits, none is yet to fully attenuate clinical progression or reverse damage to the retina. This has led to an interest in developing novel therapies for the condition, such as mediators of angiopoietin signaling axes, immunosuppressants, nonsteroidal anti-inflammatory drugs (NSAIDs), oxidative stress inhibitors and vitriol viscosity inhibitors. Further, preclinical research suggests that gene therapy treatment for DR could provide significant benefits over existing treatments options.

AREAS COVERED

Here we review the pathophysiology of DR and provide an overview of currently available treatments. We then outline recent advances made towards improved patient outcomes and highlight the potential of the gene therapy paradigm to revolutionize DR management.

EXPERT OPINION

Whilst significant progress has been made towards our understanding of DR, further research is required to enable the development of a detailed spatiotemporal model of the disease. In addition, we hope that improvements in our knowledge of the condition facilitate therapeutic innovations that continue to address unmet medical need and improve patient outcomes, with a focus on the development of targeted medicines.

The Prevalence and Risk Factors for Diabetic Retinopathy in Shiraz, Southern Iran

Globally, diabetic retinopathy (DR) is one of the leading causes of blindness, that diminishes quality of life. This study aimed to describe the prevalence of DR, and its associated risk factors. This cross-sectional study was carried out among 478 diabetic patients in a referral center in Fars province, Iran. The mean±standard deviation age of the participants was 56.64±12.45 years old and DR prevalence was 32.8%. In multivariable analysis, lower education levels (adjusted odds ratio [aOR], 0.43; 95% confidence interval [CI], 0.24 to 0.76), being overweight (aOR, 1.70; 95% CI, 1.02 to 2.83) or obese (aOR, 1.88; 95% CI, 1.09 to 3.26), diabetes duration of 10 to 20 years (aOR, 2.35; 95% CI, 1.48 to 3.73) and over 20 years (aOR, 5.63; 95% CI, 2.97 to 10.68), receiving insulin (aOR, 1.99; 95% CI, 1.27 to 3.10), and having chronic diseases (aOR, 1.71; 95% CI, 1.02 to 2.85) were significantly associated with DR. In conclusion, longer diabetes duration and obesity or having chronic diseases are strongly associated with DR suggesting that control of these risk factors may reduce both the prevalence and impact of retinopathy in Iran.

Glucagon-Like Peptide 1 Receptor Agonists and the Risk of Incident Diabetic Retinopathy

OBJECTIVE

Previous studies suggested that glucagon-like peptide 1 receptor agonists (GLP-1 RAs) may initially worsen and possibly increase the risk of diabetic retinopathy. However, data on this possible association remain limited. Thus, this population-based study aimed to determine whether use of GLP-1 RAs is associated with an increased risk of incident diabetic retinopathy.

RESEARCH DESIGN AND METHODS

Using the U.K. Clinical Practice Research Datalink (CPRD), we conducted a cohort study among 77,115 patients with type 2 diabetes initiating antidiabetic drugs between January 2007 and September 2015. Adjusted hazard ratios (HRs) and 95% CIs of incident diabetic retinopathy were estimated using time-dependent Cox proportional hazards models, comparing use of GLP-1 RAs with current use of two or more oral antidiabetic drugs. In an ancillary analysis, new users of GLP-1 RAs were compared with new users of insulin.

RESULTS

During 245,825 person-years of follow-up, 10,763 patients were newly diagnosed with diabetic retinopathy. Compared with current use of two or more oral antidiabetic drugs, use of GLP-1 RAs was not associated with an increased risk of incident diabetic retinopathy overall (HR 1.00, 95% CI 0.85-1.17). Compared with insulin, GLP-1 RAs were associated with a decreased risk of diabetic retinopathy (HR 0.67, 95% CI 0.51-0.90).

CONCLUSIONS

The associations with diabetic retinopathy varied according to the type of comparator. When compared with use of two or more oral antidiabetic drugs, use of GLP-1 RAs was not associated with an increased risk of incident diabetic retinopathy. The apparent lower risk of diabetic retinopathy associated with GLP-1 RAs compared with insulin may be due to residual confounding.

Eriodictyol inhibits high glucose-induced oxidative stress and inflammation in retinal ganglial cells

Diabetic retinopathy (DR) is one of the most common microvascular complications of diabetes mellitus and is considered as a leading cause of blindness. Oxidative stress and inflammation are significant drivers for the development of DR. Eriodictyol, a flavonoid compound, was proved to possess anti-inflammatory, antioxidative, and antidiabetic activities. However, the role of eriodictyol in DR has not been unveiled. In the current study, we explored the protective effects of eriodictyol on high glucose (HG)-induced rat retinal ganglial cells (RGCs). The results suggested that eriodictyol improved cell viability of HG-induced rat RGC-5 cells in a dose-dependent manner. Eriodictyol reduced the reactive oxygen species production and increased the activities of superoxide dismutase, glutathione peroxidase and catalase in rat RGC-5 cells in response to HG stimulation. The production of proinflammatory cytokines including tumor necrosis factor alpha and interleukin-8 was diminished after eriodictyol treatment. Eriodictyol also suppressed cell apoptosis induced HG in rat RGC-5 cells. Furthermore, eriodictyol enhanced the nuclear translocation of nuclear factor erythroid-2 (E2)-related factor 2 (Nrf2) and elevated the expression of antioxidant enzyme heme-oxygenase-1 (HO-1). These findings suggested that eriodictyol protects the RGC-5 cells from HG-induced oxidative stress, inflammation, and cell apoptosis through regulating the activation of Nrf2/HO-1 pathway.

Saving sight in China and beyond: the Lifeline Express model

Cataract and diabetic retinopathy are leading causes of blindness globally. Lifeline Express (LEX) has pioneered the provision of cataract surgery in rural China from custom-built trains and eye centres nationwide. Over the past two decades, LEX has provided free cataract surgery for over 180 000 patients in China. In China, half of the adult population has prediabetes and 113 million adults have diabetes. Recognising the rising threat of diabetic retinopathy, LEX has expanded to providing free diabetic retinopathy screening nationwide by establishing 29 Diabetic Retinopathy Screening Centres across China. Source of referrals included host hospitals, the community and out-reach mobile vans equipped with fundus cameras. Fundi photos taken in the mobile vans were electronically transferred to primary graders. LEX also leveraged the widespread smartphone use to provide electronic medical reports via WeChat, the most popular instant messenger app in China. From April 2014 to December 2016, 34 506 patients with diabetes underwent screening, of which 27.2% (9,396) were identified to have diabetic retinopathy. China's latest national health strategy ('Healthy China 2030 Plan') has championed the 'prevention first' principle and early screening of chronic diseases. LEX has accordingly evolved to extend its services to save sight in China-from cataract surgery to diabetic retinopathy screening and most recently outreaching beyond its national borders in a pilot South-South collaboration. With health at the top of the China's developmental agenda and the country's growing role in global health-LEX's large-scale telemedicine-enabled programme could represent a potentially scalable model for nationwide diabetic retinopathy screening elsewhere.

Incidence of diabetes retinopathy and determinants of time to diabetes retinopathy among diabetes patients at Tikur Anbessa Hospital, Ethiopia: a retrospective follow up study

OBJECTIVE

Data regarding diabetes retinopathy and associated factors are currently lacking in Ethiopia. The study aims to determine the incidence and determinants of time to diabetes retinopathy among diabetes mellitus patients at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia.

RESULTS

The incidence of diabetes retinopathy is a rapidly growing burden of disease in Ethiopia. The incidence rate of diabetes retinopathy was 2.65 (95% CI 2. 54, 4.05) per 1000 person-years observation. Moreover, 70 (18.57%, 95% CI 14.63, 22.5) DM patients developed diabetes retinopathy. The median time was 74.07 months (with IQR 53.60, 89.88). Male sex (AHR = 1.94, 95% CI = 1.10, 3.39), type 2 DM (AHR = 4.01, 95% CI = 1.34, 12.00), creatinine (AHR = 2.59, 95% CI = 1.91, 3.52), borderline triglyceride (AHR = 2.87, 95% CI 1.33, 6.21) and high triglyceride levels (AHR = 2.59, 95% CI = 1.31, 4.97) were positively correlated factors to diabetes retinopathy occurrence. Multisectoral, population-based approaches are needed to reduce type 2 DM complications.

Excess visceral adiposity is associated with diabetic retinopathy in a multiethnic Asian cohort with longstanding type 2 diabetes

Purpose/Aim: Diabetic retinopathy (DR) is the most common diabetic microvascular complication, and it typically develops after 10 years of diabetes diagnosis. The primary aim of this study was to evaluate the association between adiposity and DR susceptibility among individuals with longstanding type 2 diabetes mellitus (T2D).

MATERIALS AND METHODS

In this cross-sectional study, DR was assessed by fundus photography in 953 T2D subjects. DR prevalence by categories of T2D duration was evaluated. In a sub-cohort analysis, subjects having T2D for ≥10 years were divided into DR (N = 241) and non-DR (N = 377) groups. Measures of adiposity including body mass index (BMI), waist circumference (WC), and visceral fat area (VFA) were analyzed. Urinary albumin:creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR) were measured.

RESULTS

DR prevalence markedly increased 10 years after T2D diagnosis (p < 0.001). Among subjects with T2D duration ≥10 years, BMI, WC, and VFA were elevated in DR compared with non-DR (all p < 0.05). Contrasting with BMI and WC, the association between VFA and DR sustained adjustment for demographics, metabolic factors, and insulin treatment (OR: 1.060, 95% CI: 1.004-1.119, p = 0.035). However, the association became insignificant after controlling for ACR and eGFR. Mediation analysis revealed that ACR and eGFR explained 47.3% of the relationship between VFA and DR.

CONCLUSIONS

The findings suggest that visceral adiposity is associated with DR in individuals with longstanding T2D. This relationship may be attributable to generalized vascular injury as reflected by coexisting renal burden. Therefore, effective management of visceral adiposity and ameliorating renal burden may ameliorate susceptibility to DR.

Abnormally Low or High Ankle-Brachial Index Is Associated With the Development of Diabetic Retinopathy in Type 2 Diabetes Mellitus

Although some studies have reported an association between peripheral artery disease (PAD) and diabetic retinopathy (DR) in patients with diabetes, whether or not a causal relationship exists is unknown. The aim of this study was to investigate whether PAD, as indicated by an abnormally low or high ankle-brachial index (ABI), is associated with the development of DR in patients with type 2 diabetes mellitus (DM) without DR. We enrolled 414 (221 men and 193 women) patients with type 2 DM who underwent ABI measurements at our outpatient clinic. PAD was defined as an abnormally low (<0.9) or high (≥1.3) ABI in either leg, and DR was defined as being non-proliferative or proliferative. Of the enrolled patients, 69 (16.7%) had an ABI <0.9 or ≥1.3. The median follow-up period was 23 (15–40) months, during which 74 (17.9%) patients developed DR. In multivariate analysis, an ABI <0.9 or ≥1.3 was independently associated with the development of DR (vs. ABI ≥0.9 to <1.3; hazard ratio, 2.186; 95% confidence interval, 1.261 to 3.789; p = 0.005). An abnormal ABI was associated with the development of DR in our patients with type 2 DM without DR.

Ophthalmic and clinical factors that predict four-year development and worsening of diabetic retinopathy in type 1 diabetes

AIMS

To investigate the role of ophthalmic imaging markers - namely retinal thickness measures and corneal nerve morphology - in predicting four-year development and worsening of diabetic retinopathy (DR) in type 1 diabetes (T1DM).

METHODS

126 eyes of 126 participants with T1DM were examined at baseline and after four years. Diabetic retinopathy (DR) was graded using the Early Treatment Diabetic Retinopathy Study scale. HbA_1c, nephropathy, neuropathy, cardiovascular factors, and retinal thickness using optical coherence tomography (OCT) and corneal nerve fiber length (CNFL) using corneal confocal microscopy at baseline were assessed by univariate and step-wise multiple logistic regression, and their diagnostic capabilities for single and combined measures.

RESULTS

Four-year development of DR was 19% (13 of 68 without DR at baseline). Worsening of DR was seen in 43% (25 of 58 with DR at baseline). When adjusted for potential confounders, a lower CNFL (AUC=0.637, p=0.040, 64% sensitivity and 64% specificity at 14.9mm/mm² cut-off), higher triglycerides (AUC=0.669, p=0.012, 64% sensitivity, 62% specificity at 0.85mmol/L) and an elevated vibration threshold (AUC=0.708, p=0.002, 96% sensitivity, 40% specificity at 3.55Hz) were significant predictors for four-year worsening of DR.

CONCLUSIONS

Reduced CNFL, elevated vibration perception threshold and higher triglycerides can predict future worsening of DR.