To determine the incremental cost-effectiveness of a new telemedicine technician-based assessment relative to an existing model of family physician (FP)-based assessment of diabetic retinopathy (DR) ...in Singapore from the health system and societal perspectives.
Model-based, cost-effectiveness analysis of the Singapore Integrated Diabetic Retinopathy Program (SiDRP).
A hypothetical cohort of patients aged 55 years with type 2 diabetes previously not screened for DR.
The SiDRP is a new telemedicine-based DR screening program using trained technicians to assess retinal photographs. We compared the cost-effectiveness of SiDRP with the existing model in which FPs assess photographs. We developed a hybrid decision tree/Markov model to simulate the costs, effectiveness, and incremental cost-effectiveness ratio (ICER) of SiDRP relative to FP-based DR screening over a lifetime horizon. We estimated the costs from the health system and societal perspectives. Effectiveness was measured in terms of quality-adjusted life-years (QALYs). Result robustness was calculated using deterministic and probabilistic sensitivity analyses.
The ICER.
From the societal perspective that takes into account all costs and effects, the telemedicine-based DR screening model had significantly lower costs (total cost savings of S$173 per person) while generating similar QALYs compared with the physician-based model (i.e., 13.1 QALYs). From the health system perspective that includes only direct medical costs, the cost savings are S$144 per person. By extrapolating these data to approximately 170 000 patients with diabetes currently being screened yearly for DR in Singapore's primary care polyclinics, the present value of future cost savings associated with the telemedicine-based model is estimated to be S$29.4 million over a lifetime horizon.
While generating similar health outcomes, the telemedicine-based DR screening using technicians in the primary care setting saves costs for Singapore compared with the FP model. Our data provide a strong economic rationale to expand the telemedicine-based DR screening program in Singapore and elsewhere.
To test the assumption that the National Eye Institute Visual Function Questionnaire (NEI VFQ) measures visual functioning, assess the validity of its subscales, and, if flawed, revise the ...questionnaire and derive a shortened version with sound psychometric properties.
Flinders Medical Centre, Adelaide, Australia.
Patients from the cataract surgery waiting list self-administered and completed the 39-item NEI VFQ (NEI VFQ-39). Rasch analysis was applied, and the psychometric performance of the entire questionnaire and each subscale was tested. Instrument revision was performed in the context of Rasch analysis statistics.
Five hundred thirty-six patients (mean age 73.8 years) completed the questionnaire. Response categories for 2 question types were not used as intended so dysfunctional categories were combined. The NEI VFQ-39 and the 25-item version (NEI VFQ-25) had good precision but evidence of multidimensionality (more than 1 construct in 1 score), questions that did not fit the construct, suboptimum targeting of item difficulty to person ability, and dysfunctional subscales (8 NEI VFQ-39; 12 NEI VFQ-25). Questions could be reorganized into 2 constructs (a visual functioning scale and a socioemotional scale) that, after misfitting questions were removed, gave valid measurement of each construct and preserved 3 subscales. Removing redundancy from these long-form subscales yielded valid short-form scales.
Several NEI VFQ subscales were not psychometrically sound; as an overall measure, it is flawed by multidimensionality. This was repaired by segregation into visual functioning and socioemotional scales. Valid long and short forms of the scales could enhance application of the questionnaire.
IMPORTANCE: A deep learning system (DLS) is a machine learning technology with potential for screening diabetic retinopathy and related eye diseases. OBJECTIVE: To evaluate the performance of a DLS ...in detecting referable diabetic retinopathy, vision-threatening diabetic retinopathy, possible glaucoma, and age-related macular degeneration (AMD) in community and clinic-based multiethnic populations with diabetes. DESIGN, SETTING, AND PARTICIPANTS: Diagnostic performance of a DLS for diabetic retinopathy and related eye diseases was evaluated using 494 661 retinal images. A DLS was trained for detecting diabetic retinopathy (using 76 370 images), possible glaucoma (125 189 images), and AMD (72 610 images), and performance of DLS was evaluated for detecting diabetic retinopathy (using 112 648 images), possible glaucoma (71 896 images), and AMD (35 948 images). Training of the DLS was completed in May 2016, and validation of the DLS was completed in May 2017 for detection of referable diabetic retinopathy (moderate nonproliferative diabetic retinopathy or worse) and vision-threatening diabetic retinopathy (severe nonproliferative diabetic retinopathy or worse) using a primary validation data set in the Singapore National Diabetic Retinopathy Screening Program and 10 multiethnic cohorts with diabetes. EXPOSURES: Use of a deep learning system. MAIN OUTCOMES AND MEASURES: Area under the receiver operating characteristic curve (AUC) and sensitivity and specificity of the DLS with professional graders (retinal specialists, general ophthalmologists, trained graders, or optometrists) as the reference standard. RESULTS: In the primary validation dataset (n = 14 880 patients; 71 896 images; mean SD age, 60.2 2.2 years; 54.6% men), the prevalence of referable diabetic retinopathy was 3.0%; vision-threatening diabetic retinopathy, 0.6%; possible glaucoma, 0.1%; and AMD, 2.5%. The AUC of the DLS for referable diabetic retinopathy was 0.936 (95% CI, 0.925-0.943), sensitivity was 90.5% (95% CI, 87.3%-93.0%), and specificity was 91.6% (95% CI, 91.0%-92.2%). For vision-threatening diabetic retinopathy, AUC was 0.958 (95% CI, 0.956-0.961), sensitivity was 100% (95% CI, 94.1%-100.0%), and specificity was 91.1% (95% CI, 90.7%-91.4%). For possible glaucoma, AUC was 0.942 (95% CI, 0.929-0.954), sensitivity was 96.4% (95% CI, 81.7%-99.9%), and specificity was 87.2% (95% CI, 86.8%-87.5%). For AMD, AUC was 0.931 (95% CI, 0.928-0.935), sensitivity was 93.2% (95% CI, 91.1%-99.8%), and specificity was 88.7% (95% CI, 88.3%-89.0%). For referable diabetic retinopathy in the 10 additional datasets, AUC range was 0.889 to 0.983 (n = 40 752 images). CONCLUSIONS AND RELEVANCE: In this evaluation of retinal images from multiethnic cohorts of patients with diabetes, the DLS had high sensitivity and specificity for identifying diabetic retinopathy and related eye diseases. Further research is necessary to evaluate the applicability of the DLS in health care settings and the utility of the DLS to improve vision outcomes.
The evidence linking dietary intake with diabetic retinopathy (DR) is growing but unclear. We conducted a systematic review of the association between dietary intake and DR.
We systematically ...searched PubMed, Embase, Medline, and the Cochrane Central register of controlled trials, for publications between January 1967 and January 2017 using standardized criteria for diet and DR. Interventional and observational studies investigating micro- and macro-nutrient intakes; food and beverage consumptions; and dietary patterns were included. Study quality was evaluated using a modified Newcastle-Ottawa scale for observational studies, and the Cochrane collaboration tool for interventional studies.
Of 4265 titles initially identified, 31 studies (3 interventional, 28 Observational) were retained. Higher intakes of dietary fibre, oily fish, and greater adherence to a Mediterranean diet were protective of DR. Conversely, high total caloric intake was associated with higher risk of DR. No significant associations of carbohydrate, vitamin D, and sodium intake with DR were found. Associations of antioxidants, fatty acids, proteins and alcohol with DR remain equivocal.
Dietary fibre, oily fish, a Mediterranean diet and a reduced caloric intake are associated with lower risk of DR. Longitudinal data and interventional models are warranted to confirm our findings and better inform clinical guidelines.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Importance
Previous work has reported a link between diabetic retinopathy/diabetic macular edema (DR/DME) and psychosocial functioning, although the extent and direction of the association remains ...uncertain.
Objective
To determine the relationship between DR/DME and psychosocial functioning, the latter an umbrella term used to capture the emotional and social aspects of functioning which may include, for example, depression; depressive disorder; anxiety; vision-specific distress; diabetes-specific distress and emotional and social well-being.
Evidence review
PubMed, Embase, Medline and the Cochrane Central register were systematically searched for relevant interventional and observational quantitative studies using standardised criteria. Studies with DR/DME and psychosocial functioning as exposures or outcomes were accepted. Study quality was evaluated using the modified Newcastle–Ottawa scale for observational studies, and the modified Down’s and Black checklist for interventional studies.
Findings
Of 1827 titles initially identified, 42 were included in the systematic review. They comprised of four interventions (one RCT, three non-RCTs) and 38 observational studies (33 cross sectional, five prospective). In studies with DR/DME as the exposure (
n
= 28), its severity and related vision impairment were consistently associated with poor psychosocial outcomes, mostly higher incidence of depression and depressive symptoms. Baseline depression and depressive symptoms were also associated with greater DR incidence and progression of DR. Medical intervention strategies showed significant improvement in psychosocial outcomes in patients with DR, such as significant improvements in mental health domain scores of the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ 25).
Conclusion and relevance
Severity of DR, DME and associated vision loss are significantly associated with poor psychosocial outcomes. Aspects of depression and its symptoms show a bi-directional association, with increased incidence and progression of DR significant in those with baseline depression or depressive symptoms. Based on these findings, we propose two areas that may benefit from targeted interventions: (1) Prevention of development of poor psychological outcomes by preventing and delaying progression of DR/DME; and (2) Improved detection and management of poor psychological functioning by improving screening tools and multidisciplinary care for patients. Subsequent longitudinal studies can further help establish the underlying relationship between the two measures.
A critical component that influences the measurement properties of a patient-reported outcome (PRO) instrument is the rating scale. Yet, there is a lack of general consensus regarding optimal rating ...scale format, including aspects of question structure, the number and the labels of response categories. This study aims to explore the characteristics of rating scales that function well and those that do not, and thereby develop guidelines for formulating rating scales.
Seventeen existing PROs designed to measure vision-related quality of life dimensions were mailed for self-administration, in sets of 10, to patients who were on a waiting list for cataract extraction. These PROs included questions with ratings of difficulty, frequency, severity, and global ratings. Using Rasch analysis, performance of rating scales were assessed by examining hierarchical ordering (indicating categories are distinct from each other and follow a logical transition from lower to higher value), evenness (indicating relative utilization of categories), and range (indicating coverage of the attribute by the rating scale).
The rating scales with complicated question format, a large number of response categories, or unlabelled categories, tended to be dysfunctional. Rating scales with five or fewer response categories tended to be functional. Most of the rating scales measuring difficulty performed well. The rating scales measuring frequency and severity demonstrated hierarchical ordering but the categories lacked even utilization.
Developers of PRO instruments should use a simple question format, fewer (four to five) and labelled response categories.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To evaluate the prevalence and risk factors for diabetic retinopathy (DR) in the Singapore Epidemiology of Eye Diseases (SEED) Study.
Population-based, cross-sectional study.
Persons of Malay, ...Indian, and Chinese ethnicity aged 40+ years, living in Singapore.
Diabetes was defined as nonfasting plasma glucose ≥200 mg/dl (11.1 mmol/l), glycated hemoglobin A1c (HbA1c) >6.5%, self-reported physician-diagnosed diabetes, or the use of glucose-lowering medication. Retinal photographs, were graded for the presence and severity of DR using the modified Airlie House classification system.
Diabetic retinopathy, diabetic macular edema (DME), vision-threatening diabetic retinopathy (VTDR), defined as the presence of severe nonproliferative or proliferative DR, or clinically significant macular edema (CSME).
Of the 10 033 subjects, 2877 (28.7%) had diabetes and gradable photographs for analysis. The overall age-standardized prevalence (95% confidence interval CI) was 28.2% (25.9-30.6) for any DR, 7.6% (6.5-9.0) for DME, and 7.7% (6.6-9.0) for VTDR. Indians had a higher prevalence of any DR (30.7% vs. 26.2% in Chinese and 25.5% in Malays, P = 0.012); a similar trend was noted for any DME (P = 0.001) and CSME (P = 0.032). Independent risk factors for any DR were Indian ethnicity (odds ratio OR, 1.41; 95% CI, 1.09-1.83, vs. Chinese), diabetes duration (OR, 1.10; 95% CI, 1.08-1.11, per year), HbA1c (OR, 1.25; 95% CI, 1.18-1.32, per %), serum glucose (OR, 1.03; 95% CI, 1.00-1.06, per mmol/l), and systolic blood pressure (OR, 1.14; 95% CI, 1.09-1.19, per 10 mmHg). Diastolic blood pressure (OR, 0.74; 95% CI, 0.65-0.84, per 10 mmHg increase), total cholesterol (OR, 0.87; 95% CI, 0.80-0.95, per mmol/l increase), and low-density lipoprotein (LDL) cholesterol (OR, 0.83; 95% CI, 0.74-0.92, per mmol/l increase) were associated with lower odds of any DR. Risk factors were largely similar across the 3 ethnic groups.
Indian Singaporeans have a higher prevalence of DR and DME compared with Chinese and Malays. Major risk factors for DR in this study were similar across the 3 ethnic groups. Addressing these risk factors may reduce the impact of DR in Asia, regardless of ethnicity.
IMPORTANCE: This study is needed to clarify inconsistent findings regarding the association between diabetes-related eye complications and psychological well-being. OBJECTIVE: To examine the ...association between severity of diabetic retinopathy (DR) and diabetic macular edema (DME) with symptoms of depression and anxiety in adults with diabetes. DESIGN, SETTING, AND PARTICIPANTS: A cross-sectional study was conducted in a tertiary eye hospital in Melbourne, Australia. The study comprised 519 participants with diabetes. The median duration of diabetes was 13.0 (interquartile range, 14.0) years. The study was conducted from March 1, 2009, to December 24, 2010. EXPOSURES: Patients underwent a comprehensive eye examination in which dilated fundus photographs (disc and macula centered) were obtained and graded for the presence and severity of DR and DME. Presenting distance uniocular and binocular visual acuity were assessed using a 3-m logMAR chart. MAIN OUTCOMES AND MEASURES: Symptoms of depression and anxiety were measured using the Hospital Anxiety and Depression Scale (HADS), which comprises 7 questions specific to anxiety and 7 specific to depression with scores ranging from 0 to 21; scores higher than 8 signify possible anxiety or depression. The ordinal raw scores of the HADS questionnaire were transformed to estimates of interval measure using Rasch analysis and evaluated as continuous variables. Participants also completed standardized interview-administered questionnaires. Blood samples were assessed for hemoglobin A1c, fasting blood glucose, and serum lipids. Multiple linear regression models were used to determine the associations between the severity of DR and DME with symptoms of anxiety and depression and commonality analysis was used to quantify the unique variance explained. RESULTS: Of the 519 participants in the study, 170 individuals (32.8%) were female; mean (SD) age was 64.9 (11.6) years. Raw scores indicated that 80 individuals (15.4%) screened positive for depressive symptoms and 118 persons (22.7%) screened positive for symptoms of anxiety. In multivariate analysis using Rasch scores, severe nonproliferative DR (NPDR)/PDR was independently associated with greater depressive symptoms (regression coefficient β = 0.69; 95% CI, 0.03-1.34) after controlling for sociodemographic factors and clinical characteristics, including visual acuity. A history of depression or anxiety accounted for 60.6% (95% CI, 23.9%-83.2%) of the unique variance in depressive symptoms, and severe NPDR or PDR contributed to 19.1% (95% CI, 1.7%-44.4%) of the total explained variance of depressive symptoms. Diabetic macular edema was not associated with depressive symptoms. No association between DR and symptoms of anxiety was identified. CONCLUSIONS AND RELEVANCE: Severe NPDR or PDR, but not DME, was independently associated with depressive symptoms. The severity of DR could be an indicator to prompt monitoring of depression in at-risk individuals with diabetes. Further work is required to replicate these findings and determine the clinical significance of the association.
IMPORTANCE: Previous studies on the relationship between diabetic retinopathy (DR) and cardiovascular disease (CVD) focused on the early stages of DR. Understanding whether patients with type 2 ...diabetes and severe stages of DR (diabetic macular edema DME and proliferative diabetic retinopathy PDR) have a higher risk of CVD will allow physicians to more effectively counsel patients. OBJECTIVE: To examine the association of severe stages of DR (DME and PDR) with incident CVD in patients with type 2 diabetes. DATA SOURCES: English-language publications were reviewed for articles evaluating the relationship of DR and CVD in MEDLINE, EMBASE, Current Contents, and the Cochrane Library from inception (January 1, 1950) to December 31, 2014, using the search terms diabetic retinopathy OR macular edema AND stroke OR cerebrovascular disease OR coronary artery disease OR heart failure OR myocardial infarction OR angina pectoris OR acute coronary syndrome OR coronary artery disease OR cardiomyopathy. STUDY SELECTION: Among 656 studies screened for eligibility, 7604 individuals were included from 8 prospective population-based studies with data on photographic-based DR grading, follow-up visits, and well-defined incident CVD end point. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers conducted a systematic search of the 4 databases, and a single pooled database was developed. Incidence rate ratios (IRRs) were estimated for patients with DME, PDR, and vision-threatening DR, compared with persons without these conditions, by using individual participant data followed by a standard inverse-variance meta-analysis (2-step analysis). The review and analyses were performed from January 1, 2009, to January 1, 2017. MAIN OUTCOME AND MEASURES: Incident CVD, including coronary heart disease, stroke, or death from cardiovascular causes. RESULTS: Among 7604 patients with type 2 diabetes, the prevalence of DME was 4.6% and PDR, 7.4%. After a mean follow-up of 5.9 years (range, 3.2-10.1 years), 1203 incident CVD events, including 916 coronary heart disease cases, were reported. Persons with DME or PDR were more likely to have incident CVD (IRR, 1.39; 95% CI, 1.16-1.67) and fatal CVD (IRR, 2.33; 95% CI, 1.49-3.67) compared with those without DME or PDR. CONCLUSIONS AND RELEVANCE: Patients with type 2 diabetes and DME or PDR have an increased risk of incident CVD, which suggests that these persons should be followed up more closely to prevent CVD.
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