Geographic Variation in the Use of Diagnostic Testing of Patients with Newly Diagnosed Open-Angle Glaucoma

Association between metformin use and the risk of developing open-angle glaucoma among patients with diabetes: a retrospective cohort study and meta-analysis

PURPOSE

Recent studies examining the neuroprotective effects of metformin on open-angle glaucoma (OAG) have failed to provide consistent results. In this study, we investigated the association between metformin use and OAG.

METHODS

Data were obtained from a sample cohort of the Korean National Health Insurance database. Patients diagnosed with type-2 diabetes (T2DM) between 2004 and 2013 were included. We performed propensity score-matched analysis in a matched cohort (N = 20,646). The risk of the newly developed OAG was estimated using a Cox proportional hazards model. Including the present study, the meta-analysis included five studies to calculate the pooled risk for OAG based on metformin use.

RESULTS

In the adjusted model, the analysis revealed no statistical association between metformin use and OAG incidence (hazard ratio [HR] 1.05; 95% confidence interval [CI] 0.79-1.40; P = 0.738). The highest tercile of metformin use demonstrated no statistical significance (HR 0.93 [95% CI 0.63-1.37]; P = 0.703). No significant dose-dependent association was observed between the cumulative dose and incidence of OAG (P-value for trend = 0.336). In a meta-analysis of four published articles and the present study, the common-effects and random-effects models indicated conflicting results in terms of significance. The random effects model demonstrated no significant association (pooled risk ratio 0.53; 95% CI 0.24-1.19; P = 0.123).

CONCLUSION

We found no significant association between metformin use and OAG incidence in patients with T2DM in this population-based cohort study and meta-analysis. Further studies are needed to investigate the association between metformin use and the risk of OAG among patients with T2DM.

Social Vulnerability, Prevalence of Glaucoma, and Incidence of Glaucoma Surgery in the California Medicare Population

PURPOSE

To examine associations of Centers for Disease Control and Prevention/Agency for Toxic Substances and Disease Registry Social Vulnerability Index (SVI) scores with prevalence of glaucoma and incidence of glaucoma surgery in 2019 California Medicare beneficiaries.

DESIGN

Retrospective cross-sectional study.

PARTICIPANTS

2019 California Medicare beneficiaries ≥ 65 years old with part A and part B coverage.

METHODS

The exposure of interest was SVI score, which was assessed overall and by themes. Outcomes included prevalence of glaucoma in the study population and incidence of glaucoma surgery in beneficiaries with glaucoma. Logistic regression modeling was performed to assess associations between quartiles of each type of SVI score, prevalence of glaucoma, and incidence of glaucoma surgery, controlling for age, sex, race/ethnicity, Charlson Comorbidity Index score, pseudophakia, and age-related macular degeneration.

MAIN OUTCOME MEASURES

Prevalence of any glaucoma, primary open angle glaucoma (POAG), secondary open angle glaucoma (SOAG), and angle closure glaucoma in all beneficiaries. Incidence of any glaucoma surgery, trabeculectomy, tube shunt, minimally invasive glaucoma surgery (MIGS), and cyclophotocoagulation (CPC) in beneficiaries with glaucoma.

RESULTS

Of 5 725 245 beneficiaries in the total study population, there were 215 814 (3.8%) with any glaucoma, and of those with glaucoma, 10 135/215 814 (4.7%) underwent glaucoma surgery. In adjusted analyses for overall SVI score, where higher levels of SVI refer to higher levels of social vulnerability, there were decreased odds of any glaucoma (adjusted odds ratio [aOR] = 0.83; 95% confidence interval [CI] = 0.82, 0.84 for Q4 vs. Q1), POAG (aOR = 0.85; 95% CI = 0.84, 0.87 for Q4 vs. Q1), and SOAG (aOR = 0.59; 95% CI = 0.55, 0.63 for Q4 vs. Q1) in higher (Q4) vs. lower (Q1) SVI quartile. There were increased odds of any glaucoma surgery (aOR = 1.19; 95% CI = 1.12, 1.26 for Q4 vs. Q1), MIGS (aOR = 1.24; 95% CI = 1.15, 1.33 for Q4 vs. Q1), and CPC (aOR = 1.49; 95% CI = 1.29, 1.76 for Q4 vs. Q1) for higher (Q4) vs. lower (Q1) SVI quartile.

CONCLUSIONS

In the 2019 California Medicare population, there were variable associations between SVI score, prevalence of glaucoma, and incidence of glaucoma surgery. Further investigation is needed to understand the role of social, economic, and demographic factors in glaucoma care on the individual and structural levels.

FINANCIAL DISCLOSURE(S)

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

Disparities in Eye Care Access and Utilization: A Narrative Review

This narrative review summarizes the literature on factors related to eye care access and utilization in the United States. Using the Healthy People 2030 framework, this review investigates social determinants of health associated with general and follow-up engagement, screenings, diagnostic visits, treatment, technology, and teleophthalmology. We provide hypotheses for these documented eye care disparities, featuring qualitative, patient-centered research. Lastly, we provide recommendations in the hopes of appropriately eliminating these disparities and reimagining eye care.

Comparison of 10-2 and 24-2 Perimetry to Diagnose Glaucoma Using OCT as an Independent Reference Standard

PURPOSE

To compare the performance of the 10-2 test versus 24-2 standard automated perimetry (SAP) test for the diagnosis of glaucoma using OCT as an independent standard for glaucomatous damage.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 1375 pairs of 10-2 and 24-2 SAP tests from 569 eyes of 339 subjects were used for the analysis. A total of 440 (77%) eyes had a diagnosis of glaucoma, and 129 (23%) eyes were normal. All participants underwent 10-2 and 24-2 SAP tests within 30 days.

METHODS

Glaucomatous severity was quantified based on OCT macula ganglion cell layer (mGCL) and circumpapillary retinal nerve fiber layer. The area under the receiver operating characteristic (ROC) curve (AUC) was used to compare 10-2 and 24-2 metrics for discriminating healthy eyes from those of glaucoma, at different levels of disease severity.

MAIN OUTCOME MEASURES

Areas under the ROC curves and sensitivities at fixed specificities of 80% and 95%.

RESULTS

The overall AUC for mean deviation (MD) for the 24-2 test (0.808) was significantly higher than that of the 10-2 test (0.742; P < 0.001). When compared at different stages of the disease, the 24-2 test performed generally better than the 10-2 test, notably in the earlier stages of the disease. For early damage (first quartile), the 24-2 MD had an AUC of 0.658 versus 0.590 for 10-2 MD (P = 0.018). For advanced damage (fourth quartile), corresponding values were 0.954 vs. 0.903 (P = 0.013). Similar trends were observed when glaucoma severity was defined based on structural macular damage with mGCL thickness.

CONCLUSIONS

The 24-2 SAP test had better diagnostic accuracy compared with that of the 10-2 test for detecting equivalent levels of glaucomatous damage, as measured by quantitative assessment of retinal nerve fiber layer and macula by OCT.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Comparison between the Recommendations of Glaucoma Specialists and OCT Report Specialists for Further Ophthalmic Evaluation in a Community-Based Screening Study

PURPOSE

To compare glaucoma referral patterns between glaucoma and OCT report specialists and to determine what influence, if any, a designated OCT reading could have on a glaucoma specialist's judgments.

DESIGN

Retrospective, exploratory study.

SUBJECTS

We included 483 eyes (243 individuals) from high-risk New York City neighborhoods screened as part of a mobile van glaucoma screening study from July 2017 to October 2017.

METHODS

All participants underwent comprehensive testing, including visual acuity, commercial OCT imaging, gonioscopy, intraocular pressure, frequency-doubling testing, and funduscopic assessment. Three glaucoma specialists independently evaluated all the collected data to determine whether a further glaucoma workup referral was recommended. Two OCT report specialists evaluated only the OCT image for each eye using the commercial report as well as a specialized, customized report. In phase II, the glaucoma specialists then re-evaluated a subset of these eyes, this time with an OCT report specialist's judgments made available.

MAIN OUTCOME MEASURES

Comparison of glaucoma specialist referrals made by glaucoma specialists versus OCT report specialists.

RESULTS

Intergrader agreement between glaucoma specialists was 60% (κ = 0.43) and between report specialists was 95% (κ = 0.77). There was an agreement between a single OCT report specialist and the consensus (2 of 3) of glaucoma specialists in 74% of eyes (κ= 0.32). Of the eyes studied, 25% were referred for further glaucoma evaluation by the glaucoma specialists alone and 1% were referred for further glaucoma workup by only the report specialist. With the addition of the report specialist's judgments, referral pattern changes varied by glaucoma specialist but overall agreement increased to 85% (κ = 0.53).

CONCLUSIONS

There was a fair level of agreement regarding glaucoma referral recommendations between glaucoma specialists with access to comprehensive screening data and OCT report specialists with access to only OCT data. Overall agreement increased when the designated OCT evaluation was made available to the glaucoma specialists. These results may aid in the design of future large-scale glaucoma screening studies.

Disparities in Vision Health and Eye Care

Significant disparities in vision health and eye care exist. To achieve health equity, we must understand the root causes and drivers of health disparities and inequities, including social determinants of health and systemic racism.

Artificial Intelligence for Glaucoma: Creating and Implementing Artificial Intelligence for Disease Detection and Progression

On September 3, 2020, the Collaborative Community on Ophthalmic Imaging conducted its first 2-day virtual workshop on the role of artificial intelligence (AI) and related machine learning techniques in the diagnosis and treatment of various ophthalmic conditions. In a session entitled "Artificial Intelligence for Glaucoma," a panel of glaucoma specialists, researchers, industry experts, and patients convened to share current research on the application of AI to commonly used diagnostic modalities, including fundus photography, OCT imaging, standard automated perimetry, and gonioscopy. The conference participants focused on the use of AI as a tool for disease prediction, highlighted its ability to address inequalities, and presented the limitations of and challenges to its clinical application. The panelists' discussion addressed AI and health equities from clinical, societal, and regulatory perspectives.

Rates of Visual Field Change in Patients With Glaucoma and Healthy Individuals: Findings From a Median 25-Year Follow-up

Importance

Estimating the rate of glaucomatous visual field change provides practical assessment of disease progression and has implications for management decisions.

Objective

To assess the rates of visual field change in patients receiving treatment for glaucoma compared with healthy individuals over an extensive follow-up period and to quantify the impact of important covariates for these rates.

Design, Setting, and Participants

This prospective longitudinal cohort study was conducted in a hospital-based setting from January 1991 to February 2020. The study included 40 patients receiving treatment for open-angle glaucoma and 29 healthy participants. One eye of each participant was randomly selected as the study eye.

Exposures

Patients with glaucoma and healthy participants received testing with standard automated perimetry every 6 months. Individual rates of mean sensitivity change were computed using ordinary least-squares regression analysis, and linear mixed-effects modeling was used to estimate the mean rates of mean sensitivity change in the 2 groups and the impact of baseline mean sensitivity, baseline age, and follow-up intraocular pressure for rate estimates.

Main Outcomes and Measures

Rate of mean sensitivity change in patients with glaucoma and healthy participants.

Results

A total of 40 patients with glaucoma (median age, 53.07 years [IQR, 48.34-57.97 years]; 21 men [52%]) and 29 healthy participants (median age, 48.80 years [IQR, 40.40-59.07 years], 17 women [59%]) were followed up for a median of 25.65 years (IQR, 22.49-27.02 years) and 19.56 years (IQR, 16.19-26.21 years), respectively. Most participants (65 individuals [94%]) self-identified as White, with the exception of 2 patients with glaucoma (1 self-identified as Black and 1 as South Asian) and 2 healthy participants (both self-identified as South Asian). The mean follow-up intraocular pressure of patients with glaucoma (median, 15.83 mm Hg [IQR, 13.05-17.33 mm Hg]) was similar to that of healthy participants (median, 14.94 mm Hg [IQR, 13.28-16.01 mm Hg]; P = .25). In an ordinary least-squares regression analysis, 31 patients (78%) with glaucoma had rates of mean sensitivity change within the range of healthy participants (ie, between -0.20 dB/y and 0.15 dB/y). Linear mixed-effects modeling revealed that the mean (SE) rate of mean sensitivity change in healthy participants was 0.003 (0.033) dB/y (95% CI, -0.062 to 0.068; P = .93). In comparison, patients with glaucoma had a mean (SE) rate of mean sensitivity change that was -0.032 (0.052) dB/y faster, but this difference was not statistically significant (95% CI, -0.134 to 0.070; P = .53). Among covariates, only baseline mean sensitivity was associated with the rate of mean sensitivity change (mean [SE], 0.021 [0.010] dB/y/dB; 95% CI, 0.002-0.041; P = .03).

Conclusions and Relevance

The results of this cohort study suggest that over a median follow-up of more than 25 years, the rate of visual field change in patients receiving treatment for glaucoma was comparable to that of healthy individuals. These findings could guide practitioners in making management decisions.

Value of 10-2 Visual Field Testing in Glaucoma Patients with Early 24-2 Visual Field Loss

PURPOSE

To determine whether the 10-2 test of the Humphrey Field Analyzer detected a higher proportion of abnormal visual fields compared with the 24-2 test in the central 10° of patients with early glaucomatous visual field damage.

DESIGN

Prospective observational study.

PARTICIPANTS

Patients with open-angle glaucoma and healthy control participants.

METHODS

All participants underwent a 24-2 and 10-2 test. Only the 12 central test locations of the 24-2 test were included to analyze equivalent visual field areas. The performance of the 2 tests was compared across 4 pointwise criteria: total deviation (TD) and pattern deviation (PD) analyses at the 5% and 2% levels. Analyses also were conducted for 2 pairs of follow-up tests, each performed 4 months apart.

MAIN OUTCOME MEASURES

(1) Area under the receiver operating characteristic curve (AUC), (2) sensitivity at identically matched specificity for the 4 criteria, (3) overlap (entire field and by quadrant) of abnormal visual fields with both tests, and (4) repeatability of the findings in 2 subsequent follow-up tests.

RESULTS

One eye each of 97 glaucoma patients (median mean deviation, -2.31 dB) and 65 control participants were included in the study. The AUCs for the 24-2 and 10-2 tests were not significantly different for any of the 4 criteria and ranged from 0.88 to 0.93 and from 0.91 to 0.94, respectively. At matched specificity, the sensitivity of the 24-2 test was significantly higher for all criteria except for PD analysis at 5%. In patients with an abnormal field with either test, the overlap varied from 60% to 86% depending on the criterion, whereas by quadrant, concordance ranged from 70% to 87%. Over the follow-up, the repeatability of test results (both 24-2 and 10-2 abnormal, either abnormal, or both normal) was achieved in 55% to 70% of patients.

CONCLUSIONS

In this study of glaucoma patients with early damage with the 24-2 test, there was little evidence that adding the 10-2 test revealed additional undetected defects in the central visual field. It may be more prudent to reserve 10-2 testing for following up selected patients with higher risk of central visual field progression.

Systematic review of the appropriateness of eye care delivery in eye care practice

BACKGROUND

Health care systems are continually being reformed, however care improvement and intervention effectiveness are often assumed, not measured. This paper aimed to review findings from published studies about the appropriateness of eye care delivery, using existing published evidence and/or experts' practice and to describe the methods used to measure appropriateness of eye care.

METHODS

A systematic search was conducted using Medline, Embase and CINAHL (2006 to September 2016). Studies reporting the processes of eye care delivery against existing published evidence and/or experts' practice were selected. Data was extracted from published reports and the methodological quality using a modified critical appraisal tool. The primary outcomes were percentage of appropriateness of eye care delivery. This study was registered with PROSPERO, reference CRD42016049974.

RESULTS

Fifty-seven studies were included. Most studies assessed glaucoma and diabetic retinopathy and the overall methodological quality for most studies was moderate. The ranges of appropriateness of care delivery were 2-100% for glaucoma, 0-100% for diabetic retinopathy and 0-100% for other miscellaneous conditions. Published studies assessed a single ocular condition, a sample from a single centre or a single domain of care, but no study has attempted to measure the overall appropriateness of eye care delivery.

CONCLUSIONS

These findings indicated a wide range of appropriateness of eye care delivery, for glaucoma and diabetic eye care. Future research would benefit from a comprehensive approach where appropriateness of eye care is measured across multiple conditions with a single methodology, to guide priorities within eye care delivery and monitor quality improvement initiatives.

Determinants in Initial Treatment Choice for Diabetic Macular Edema

PURPOSE

To assess how patient choices (out-of-pocket costs, insurance plan, geographic region) impact initiation of therapy for diabetic macular edema (DME).

DESIGN

Retrospective cohort study using administrative medical claims data from a large, national insurer.

PARTICIPANTS

All patients newly diagnosed with DME from 2013 through 2016 were observed for 90 days after diagnosis or until first treatment was received.

METHODS

Multivariate logistic regression was used to create odds ratios comparing different baseline demographic and patient-related factors.

MAIN OUTCOME MEASURES

The primary outcome was the odds of receiving the different possible initial treatments for DME (anti-vascular endothelial growth factor [VEGF], focal laser treatment, steroids, or observation), no treatment, and not following up.

RESULTS

Of the 6220 newly diagnosed DME patients, 3010 (48.4%) underwent a follow-up examination within 90 days of diagnosis, and of those, 1453 patients (48.3%) received treatment in the observation window, including 614 (20.4%) with bevacizumab, 191 (6.3%) with ranibizumab or aflibercept, 560 (18.6%) with focal laser, 38 (1.3%) with steroid injection, and 50 (1.7%) with an injection of an unspecified drug. Having a copay (vs. $0) lowered the odds of receiving any treatment (odds ratio [OR] = 0.60; 95% confidence interval [CI], 0.51-0.71; P < 0.001) and of receiving each treatment individually (anti-VEGF treatment: OR = 0.72; 95% CI, 0.59-0.88; bevacizumab: OR = 0.73; 95% CI, 0.59-0.91; ranibizumab or aflibercept: OR, 0.70; 95% CI, 0.49-0.99; focal laser: OR = 0.44; 95% CI, 0.35-0.55; P < 0.001). Contrary to having a copay, having a high deductible and type of insurance plan were not associated with initiating treatment (P > 0.41 for all comparisons). Patients in the Northeast showed lower odds of initiating anti-VEGF treatment (OR = 0.60; 95%CI, 0.44-0.82; P < 0.001) and specifically bevacizumab (OR = 0.47; 95% CI, 0.33-0.67; P < 0.001). Furthermore, Northeast patients who were treated with anti-VEGF showed a higher odds of receiving ranibizumab or aflibercept compared with bevacizumab (OR = 2.39; 95% CI, 1.31-4.37; P < 0.001). Southern Midwest patients showed a higher odds of treatment (anti-VEGF: OR = 1.35; 95%CI, 1.02-1.77; P < 0.001; bevacizumab: OR = 1.40; 95% CI, 1.04-1.87; focal laser: OR = 1.39; 95% CI, 1.01-1.89; P < 0.001).

CONCLUSIONS

Patient choices such as copays and where they live are important factors in determining the initial choice of treatment for DME.

Establishing a Regional Glaucoma Physician Collaborative to Improve Quality of Care

PURPOSE

Improving adherence to practice guidelines can improve patient safety and quality of care. We sought to establish a regional glaucoma physician collaborative to evaluate and improve adherence to the American Academy of Ophthalmology's Primary Open-angle Glaucoma (POAG) Preferred Practice Pattern (PPP) guidelines.

DESIGN

Prospective interventional study.

METHODS

The collaborative consisted of 13 glaucoma specialists from 3 practices in Michigan. All consecutive POAG new patient visits were reviewed from each study site to determine physician adherence to the 13 major examination elements of the PPP. In phase 1 of the study, physician adherence rates for each of the recommended examination elements were combined and averaged for all groups. Averages for the collaborative were reported to each site, and each physician received his or her individual adherence rates. Physicians discussed strategies to improve overall adherence to the PPP. Adherence rates were collected in phase 2 to determine if feedback and sharing of strategies resulted in improved adherence.

RESULTS

A total of 274 new POAG patient visits from phase 1 and 280 visits from phase 2 were reviewed. After accounting for multiple comparisons, overall improvement approached statistical significance for the evaluation of visual function (91.2% to 96.1%, P < .02) and target intraocular pressure determination (73.7% to 83.2%, P < .01). Improvement for other measures that had a high rate of adherence at baseline (eg, ocular history, pupil examination, and central corneal thickness measurement) was not statistically significant.

CONCLUSIONS

It is feasible to establish a regional glaucoma physician collaborative to improve standardization of care for patients with newly diagnosed POAG.

The value of visual field testing in the era of advanced imaging: clinical and psychophysical perspectives

White‐on‐white standard automated perimetry (SAP) is widely used in clinical and research settings for assessment of contrast sensitivity using incremental light stimuli across the visual field. It is one of the main functional measures of the effect of disease upon the visual system. SAP has evolved over the last 40 years to become an indispensable tool for comprehensive assessment of visual function. In modern clinical practice, a range of objective measurements of ocular structure, such as optical coherence tomography, have also become invaluable additions to the arsenal of the ophthalmic examination. Although structure‐function correlation is a highly desirable determinant of an unambiguous clinical picture for a patient, in practice, clinicians are often faced with discordance of structural and functional results, which presents them with a challenge. The construction principles behind the development of SAP are used to discuss the interpretation of visual fields, as well as the problem of structure‐function discordance. Through illustrative clinical examples, we provide useful insights to assist clinicians in combining a range of clinical results obtained from SAP and from advanced imaging techniques into a coherent picture that can help direct clinical management.

Organizational Benchmarks for Test Utilization Performance: An Example Based on Positivity Rates for Genetic Tests

OBJECTIVES

Health care organizations are under increasing pressure to deliver value by improving test utilization management. Many factors, including organizational factors, could affect utilization performance. Past research has focused on the impact of specific interventions in single organizations. The impact of organizational factors is unknown. The objective of this study is to determine whether testing patterns are subject to organizational effects, ie, are utilization patterns for individual tests correlated within organizations.

METHODS

Comparative analysis of ordering patterns (positivity rates for three genetic tests) across 659 organizations. Hierarchical regression was used to assess the impact of organizational factors after controlling for test-level factors (mutation prevalence) and hospital bed size.

RESULTS

Test positivity rates were correlated within organizations.

CONCLUSIONS

Organizations have a statistically significant impact on the positivity rate of three genetic tests.