Strategies to Screen for Diabetic Retinopathy in Chinese Patients with Newly Diagnosed Type 2 Diabetes: A Cost-Effectiveness Analysis

Risk factors for diabetic retinopathy, diabetic macular edema, and sight-threatening diabetic retinopathy

OBJECTIVE

To identify the risk factors for the development of diabetic retinopathy (DR), diabetic macular edema (DME), and sight-threatening DR (STDR) based on a city-wide diabetes screening program.

RESEARCH DESIGN AND METHODS

Diabetic patients were prospectively recruited between June 2016 and December 2022. All patients underwent dilated fundus photography centered on the disc and macula or macular spectral domain optical coherence tomography (SD-OCT) scan. Complete medical history was documented. Systematic examination, blood analysis, and urinalysis were performed. Multivariate logistic regression analysis adjusting for age and sex was conducted.

RESULTS

Out of 7274 diabetic patients, 6840 had gradable images, among which 3054 (42.0%) were graded as DR, 1153 (15.9%) as DME, and 1500 (20.6%) as STDR. The factors associated with DR, DME, and STDR included younger age (odds ratio [OR]: 0.96, 0.97, and 0.96 respectively), lower BMI (OR: 0.97, 0.95, and 0.95 respectively), longer duration of diabetes (OR: 1.07, 1.03, and 1.05 respectively) and positive of urinary albumin (OR: 2.22, 2.56, and 2.88 respectively). Other associated factors included elevated blood urea nitrogen (OR: 1.22, 1.28, and 1.27 respectively), higher LDL-cholesterol, lower blood hemoglobin (OR: 0.98, 0.98, and 0.98), insulin intake, presence of diabetic foot pathologies and diabetic peripheral neuropathy. We also identified novel risk factors, including high serum potassium (OR: 1.37, 1.46, and 1.55 respectively), high-serum sodium (OR: 1.02, 1.02, and 1.04 respectively). Better family income was a protective factor for DR, DME, and STDR. Alcohol consumption once a week was also identified as a protective factor for DR.

CONCLUSIONS

Similar risk factors for DR, DME, and STDR were found in this study. Our data also indicates high serum sodium, high serum potassium, low blood hemoglobin, and level of family income as novel associated factors for DR, DME, and STDR, which can help with DR monitoring and management.

Measuring Quality of Life in Diabetic Retinal Disease: A Narrative Review of Available Patient-Reported Outcome Measures

Topic

Several patient-reported outcome measures (PROMs) are available to measure health-related quality of life (HRQoL) in patients with late-stage clinical diabetic retinal diseases (DRDs). However, an understanding of the psychometric properties of PROMs is needed to assess how they could relate to severity levels of a revised DRD grading system. This narrative review assessed the available generic-, vision-, and DRD-related PROMs used in DRD research and highlights areas for improvement.

Clinical Relevance

Diabetic retinal disease is a common complication of diabetes and can lead to sight-threatening complications with a devastating effect on HRQoL.

Methods

The Quality of Life working group is one of 6 working groups organized for the DRD Staging System Update Effort, a project of the Juvenile Diabetes Research Foundation Mary Tyler Moore Vision Initiative. PubMed, Cochrane Library, Embase, and Google Scholar databases were searched using core keywords to retrieve ophthalmology-related review articles, randomized clinical trials, and prospective, observational, and cross-sectional studies in the English language. A detailed review of 12 PROMs (4 QoL questionnaires and 8 utilities) that met a minimum level of evidence (LOE) was conducted. The relevance of each PROM to DRD disease stage and Biomarker Qualification guidelines (Biomarkers, EndpointS, and other Tools) categories was also defined.

Results

The National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ-25), Impact of vision impairment-computerized adaptive testing, and Diabetic Retinopathy and Macular Edema Computerized Adaptive Testing System had a LOE of II in detecting change due to late-stage DRD (diabetic macular edema), although several areas for improvement (e.g., psychometrics and generalizability) were identified. Other PROMs, particularly the utilities, had a LOE of III due to cross-sectional evidence in late-stage clinical DRD. Although the NEI VFQ-25 has been the most widely used PROM in late-stage DRD, more work is required to improve its multidimensional structure and other psychometric limitations. No PROM was deemed relevant for subclinical or early/mid-DRD.

Conclusion

This narrative review found that the most commonly used PROM is NEI VFQ-25, but none meets the ideal psychometric, responsiveness, and clinical setting digital administration requirements that could be included in an updated DRD staging system for diagnosis and monitoring of DRD progression.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Telehealth Screening for Diabetic Retinopathy: Economic Modeling Reveals Cost Savings

Introduction: The use of telehealth screening (TS) for diabetic retinopathy (DR) consists of fundus photography in a primary care setting with remote interpretation of images. TS for DR is known to increase screening utilization and reduce vision loss compared with standard in-person conventional diabetic retinal exam (CDRE). Anti-vascular endothelial growth factor intravitreal injections have become standard of care for the treatment of DR, but they are expensive. We investigated whether TS for DR is cost-effective when DR management includes intravitreal injections using national data. Materials and Methods: We compared cost and effectiveness of TS and CDRE using decision-tree analysis and probabilistic sensitivity analysis with Monte Carlo simulation. We considered the disability weight (DW) of vision impairment and 1-year direct medical costs of managing patients based on Medicare allowable rates and clinical trial data. Primary outcomes include incremental costs and incremental effectiveness. Results: The average annual direct cost of eye care was $196 per person for TS and $275 for CDRE. On average, TS saves $78 (28%) compared with CDRE and was cost saving in 88.9% of simulations. The average DW outcome was equivalent in both groups. Discussion: Although this study was limited by a 1-year time horizon, it provides support that TS for DR can reduce costs of DR management despite expensive treatment with anti-VEGF agents. TS for DR is equally effective as CDRE at preserving vision. Conclusions: Annual TS for DR is cost saving and equally effective compared with CDRE given a 1-year time horizon.

Cost-effectiveness and cost-utility of traditional and telemedicine combined population-based age-related macular degeneration and diabetic retinopathy screening in rural and urban China

BACKGROUND

To assess the cost-effectiveness and cost-utility of a population-level traditional and telemedicine combined age-related macular degeneration (AMD) and diabetic retinopathy (DR) screening program in rural and urban China.

METHODS

Decision-analytic Markov models were conducted to evaluate the costs and benefits of traditional and telemedicine combined AMD and DR screening from a societal perspective. A cohort of all participants aged 50 years old and above was followed through a total of 30 1-year Markov cycles. Separate analyses were performed for rural and urban settings. Relevant parameters such as the prevalence of AMD and DR, transition probability, compliance with screening and treatment, screening sensitivity, specificity, utility, and mortality were collected from published studies specific to China, other Asian counties' studies, or unpublished data sources such as the National Committee for the Prevention of Blindness. Costs of screening, full examination, and treatment come from the real medical environments and unified pricing of Beijing Municipal Medical Insurance Bureau. Primary outcomes were incremental cost-utility ratios (ICURs) using quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) using years of blindness avoided. One-way deterministic and simulated probabilistic sensitivity analyses were conducted to reflect uncertainty.

FINDINGS

Under the status quo, the total expected medical costs for a 50-year-old patient with AMD or DR were $869·59 and $1,514·18 in rural and urban settings, respectively. Both traditional and telemedicine screening were highly cost-effective. In rural settings, ICURs were $191 (95% confidence interval [CI]: $66 to $239) and $199 (95% CI: $-12 to $217), and ICERs were $2,436 (95% CI: $1,089 to $3,254) and $2,441 (95% CI: $1,452 to $3,900) for traditional and telemedicine screening separately. Even more surprising, both screening strategies dominated no screening in urban settings. Our results were insensitive and robust to extensive sensitivity analyses. Among all acceptable screening intervals (from 1 to 5 years), annual screening could not only produce biggest benefits but also keep ICERs less than three times and one time the per capita gross domestic product (GDP) in rural and urban settings separately. When compared with traditional screening, ICERs of telescreening were less than three times the per capita GDP in rural settings ($2,559 to $8,809) and less than one time the per capita GDP in urban settings (less than $5,564), annual telescreening produced the biggest benefits, it could avert 119 and 270 years of blindness in rural and urban areas separately when 100,000 people were screened.

INTERPRETATION

We performed decision-analytic Markov models for combined AMD and DR screening in rural and urban China, and the results showed that population-level combined screening for AMD and DR is likely to be highly cost-effective in both rural and urban China for people over 50 years old. Optimal screening may have an interval of every year based on teleophthalmology platforms. In the future, China should pay more attention to chronic eye diseases and the government should establish a sound chronic disease management system and make every patient enjoy equal medical services.

FUNDING

National Natural Science Foundation of China, NSFC (82171051); the Major Innovation Platform of Public Health & Disease Control and Prevention, Renmin University of China and Beijing Nova program (Z191100001119072).

Cost-Utility Analysis of Screening for Diabetic Retinopathy in China

Background. Diabetic retinopathy (DR) has been primarily indicated to cause vision impairment and blindness, while no studies have focused on the cost-utility of telemedicine-based and community screening programs for DR in China, especially in rural and urban areas, respectively.Methods. We developed a Markov model to calculate the cost-utility of screening programs for DR in DM patients in rural and urban settings from the societal perspective. The incremental cost-utility ratio (ICUR) was calculated for the assessment.Results. In the rural setting, the community screening program obtained 1 QALY with a cost of $4179 (95% CI 3859 to 5343), and the telemedicine screening program had an ICUR of $2323 (95% CI 1023 to 3903) compared with no screening, both of which satisfied the criterion of a significantly cost-effective health intervention. Likewise, community screening programs in urban areas generated an ICUR of $3812 (95% CI 2906 to 4167) per QALY gained, with telemedicine screening at an ICUR of $2437 (95% CI 1242 to 3520) compared with no screening, and both were also cost-effective. By further comparison, compared to community screening programs, telemedicine screening yielded an ICUR of 1212 (95% CI 896 to 1590) per incremental QALY gained in rural setting and 1141 (95% CI 859 to 1403) in urban setting, which both meet the criterion for a significantly cost-effective health intervention.Conclusions. Both telemedicine and community screening for DR in rural and urban settings were cost-effective in China, and telemedicine screening programs were more cost-effective.

Cost-effectiveness of the Da Qing diabetes prevention program: A modelling study

Objective

The Da Qing Diabetes Prevention program (DQDP) was a randomized lifestyle modification intervention conducted in 1986 for the prevention and control of type 2 diabetes in individuals with impaired glucose tolerance. The current study estimated long-term cost-effectiveness of the program based on the health utilities from the Chinese population.

Methods

A Markov Monte Carlo model was developed to estimate the impact of the intervention from the healthcare system perspective. The analysis was run over 30-year and lifetime periods and costs were estimated respectively as health management service costs. Baseline characteristics and intervention effects were assessed from the DQDP. Utilities and costs were generated from relevant literature. The outcome measures were program cost per quality-adjusted life-years (QALYs) gained and incremental cost-effectiveness ratio (ICER) of the intervention. Sensitivity analyses and threshold analyses were performed.

Results

Using a 30-year horizon, the intervention strategy was cost-saving and was associated with better health outcomes (increase of 0.74 QALYs per intervention participant). Using a lifetime horizon, the intervention strategy was cost-saving and was associated with additional 1.44 QALYs. Sensitivity analyses showed that the overall ICER was most strongly influenced by the hazard ratio of cardiovascular disease event.

Conclusions

The Da Qing lifestyle intervention in a Chinese population with impaired glucose tolerance is likely to translate into substantial economic value. It is cost-saving over a 30-year time and lifetime frame.

A Clinical Decision Support System for Diabetic Retinopathy Screening: Creating a Clinical Support Application

BACKGROUND

The aim of this study was to build a clinical decision support system (CDSS) in diabetic retinopathy (DR), based on type 2 diabetes mellitus (DM) patients.

METHOD

We built a CDSS from a sample of 2,323 patients, divided into a training set of 1,212 patients, and a testing set of 1,111 patients. The CDSS is based on a fuzzy random forest, which is a set of fuzzy decision trees. A fuzzy decision tree is a hierarchical data structure that classifies a patient into several classes to some level, depending on the values that the patient presents in the attributes related to the DR risk factors. Each node of the tree is an attribute, and each branch of the node is related to a possible value of the attribute. The leaves of the tree link the patient to a particular class (DR, no DR).

RESULTS

A CDSS was built with 200 trees in the forest and three variables at each node. Accuracy of the CDSS was 80.76%, sensitivity was 80.67%, and specificity was 85.96%. Applied variables were current age, gender, DM duration and treatment, arterial hypertension, body mass index, HbA1c, estimated glomerular filtration rate, and microalbuminuria.

DISCUSSION

Some studies concluded that screening every 3 years was cost effective, but did not personalize risk factors. In this study, the random forest test using fuzzy rules permit us to build a personalized CDSS.

CONCLUSIONS

We have developed a CDSS that can help in screening diabetic retinopathy programs, despite our results more testing is essential.

Automated Diabetic Retinopathy Image Assessment Software: Diagnostic Accuracy and Cost-Effectiveness Compared with Human Graders

OBJECTIVE

With the increasing prevalence of diabetes, annual screening for diabetic retinopathy (DR) by expert human grading of retinal images is challenging. Automated DR image assessment systems (ARIAS) may provide clinically effective and cost-effective detection of retinopathy. We aimed to determine whether ARIAS can be safely introduced into DR screening pathways to replace human graders.

DESIGN

Observational measurement comparison study of human graders following a national screening program for DR versus ARIAS.

PARTICIPANTS

Retinal images from 20 258 consecutive patients attending routine annual diabetic eye screening between June 1, 2012, and November 4, 2013.

METHODS

Retinal images were manually graded following a standard national protocol for DR screening and were processed by 3 ARIAS: iGradingM, Retmarker, and EyeArt. Discrepancies between manual grades and ARIAS results were sent to a reading center for arbitration.

MAIN OUTCOME MEASURES

Screening performance (sensitivity, false-positive rate) and diagnostic accuracy (95% confidence intervals of screening-performance measures) were determined. Economic analysis estimated the cost per appropriate screening outcome.

RESULTS

Sensitivity point estimates (95% confidence intervals) of the ARIAS were as follows: EyeArt 94.7% (94.2%-95.2%) for any retinopathy, 93.8% (92.9%-94.6%) for referable retinopathy (human graded as either ungradable, maculopathy, preproliferative, or proliferative), 99.6% (97.0%-99.9%) for proliferative retinopathy; Retmarker 73.0% (72.0 %-74.0%) for any retinopathy, 85.0% (83.6%-86.2%) for referable retinopathy, 97.9% (94.9%-99.1%) for proliferative retinopathy. iGradingM classified all images as either having disease or being ungradable. EyeArt and Retmarker saved costs compared with manual grading both as a replacement for initial human grading and as a filter prior to primary human grading, although the latter approach was less cost-effective.

CONCLUSIONS

Retmarker and EyeArt systems achieved acceptable sensitivity for referable retinopathy when compared with that of human graders and had sufficient specificity to make them cost-effective alternatives to manual grading alone. ARIAS have the potential to reduce costs in developed-world health care economies and to aid delivery of DR screening in developing or remote health care settings.