Frequency Doubling Technology Perimetry and Changes in Quality of Life of Glaucoma Patients: A Longitudinal Study

Visual field loss and falls requiring hospitalisation: results from the eFOVID study

BACKGROUND

Visual fields are important for postural stability and ability to manoeuvre around objects.

OBJECTIVE

Examine the association between visual field loss and falls requiring hospitalisation in adults aged 50 +.

METHODS

Older adults aged 50+ with and without visual field loss were identified using a fields database obtained from a cross-section of ophthalmologists' practices in Western Australia (WA). Data were linked to the Hospital Morbidity Data Collection and WA Hospital Mortality System to identify participants who experienced falls-related hospitalisations between 1990 and 2019. A generalised linear negative binomial regression model examined the association between falls requiring hospitalisation for those with and without field loss, based on the better eye mean deviation (mild: -2 to -6 dB, moderate: -6.01 dB to -12 dB, severe < -12.01 dB) in the most contemporaneous visual field test (3 years prior or if not available, 2 years after the fall), after adjusting for potential confounders.

RESULTS

A total of 31 021 unique individuals of whom 6054 (19.5%) experienced 11 818 falls requiring hospitalisation during a median observation time of 14.1 years. Only mean deviation index of <-12.01 dB (severe) was significantly associated with an increased rate of falls requiring hospitalisations by 14% (adjusted IRR 1.14, 95% CI 1.0-1.25) compared with no field loss, after adjusting for potential confounders. Other factors included age, with those aged 80+ having an increased rate (IRR 29.16, 95% CI 21.39-39.84), other comorbid conditions (IRR 1.49, 95% CI 1.38-1.60) and diabetes (IRR 1.25, 95% CI 1.14-1.37). Previous cataract surgery was associated with a decreased rate of falls that required hospitalisations by 13% (IRR 0.87, 95% CI 0.81-0.95) compared with those who did not have cataract surgery.

CONCLUSION

The findings highlight the importance of continuous clinical monitoring of visual field loss and injury prevention strategies for older adults with visual field loss.

Endpoints for clinical trials in ophthalmology

With the identification of novel targets, the number of interventional clinical trials in ophthalmology has increased. Visual acuity has for a long time been considered the gold standard endpoint for clinical trials, but in the recent years it became evident that other endpoints are required for many indications including geographic atrophy and inherited retinal disease. In glaucoma the currently available drugs were approved based on their IOP lowering capacity. Some recent findings do, however, indicate that at the same level of IOP reduction, not all drugs have the same effect on visual field progression. For neuroprotection trials in glaucoma, novel surrogate endpoints are required, which may either include functional or structural parameters or a combination of both. A number of potential surrogate endpoints for ophthalmology clinical trials have been identified, but their validation is complicated and requires solid scientific evidence. In this article we summarize candidates for clinical endpoints in ophthalmology with a focus on retinal disease and glaucoma. Functional and structural biomarkers, as well as quality of life measures are discussed, and their potential to serve as endpoints in pivotal trials is critically evaluated.

Vision-Related Quality of Life Among Healthy, Preperimetric Glaucoma, and Perimetric Glaucoma Patients

PURPOSE

To investigate the association of vision-related quality of life (VRQOL) with the central visual field and macular ganglion cell complex (GCC) thickness in healthy control participants, patients with preperimetric glaucoma, and patients with perimetric glaucoma.

DESIGN

Retrospective cross-sectional study.

METHODS

A total of 39 healthy, 34 preperimetric glaucoma, and 145 perimetric glaucoma patients completed the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ). A linear mixed-effect models was used to investigate the association between the glaucoma stage as measured by binocular 10-2 visual field mean sensitivity (VFMS) and GCC thickness with the Rasch-calibrated NEI-VFQ score.

RESULTS

A total of 436 eyes from 218 participants (mean age = 67.2 [95% CI = 65.1 to 69.2] years) were enrolled. VRQOL calculated by the NEI-VFQ Rasch-calibrated score was worst for patients with perimetric glaucoma (50.7 [95% CI = 47.2 to 54.2]), followed by patients with preperimetric glaucoma (41.2 [95% CI = 34.5 to 47.9]) and healthy controls (29.3 [95% CI = 24.0 to 34.7]. Worse VRQOL had a moderate association with a worse global binocular 10-2 VFMS (-3.4 [95% CI = -5.0 to -1.9] dB per 1 score; P < .001; adjusted R² = 0.27), but not with a thinner global GCC in the better eye (-0.1 [95% CI = -0.2 to 0.1] µm per 1 score; P =.0485; adjusted R² = 0.17).

CONCLUSIONS

These findings suggest that patients with perimetric and preperimetric glaucoma have worse VRQOL than patients with healthy eyes. As compared to macular thickness measurements, the central visual field is more strongly associated with VRQOL and may better help to identify patients in need of intervention.

Association of an Objective Structural and Functional Reference Standard for Glaucoma with Quality of Life Outcomes

PURPOSE

To compare self-reported quality-of-life (QoL) outcomes of patients diagnosed as normal, glaucoma suspect, and glaucoma based on an objective reference standard for glaucomatous optic neuropathy (GON).

DESIGN

Cross-sectional study.

PARTICIPANTS

1884 eyes of 1019 patients were included in the study.

METHODS

The data was sourced from the Duke Glaucoma Registry. Eyes were classified according to the presence and topographic correspondence of functional and structural damage, as assessed by parameters from standard automated perimetry (SAP) and spectral-domain OCT (SD-OCT). The objective diagnosis of the worse eye was used to define patient-level diagnosis. To assess QoL in the diagnostic groups, 14 unidimensional vision-related items of the National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) were used to assess QoL in the diagnostic groups. Association between NEI VFQ-25 Rasch-calibrated scores and diagnostic groups was assessed through multivariable regression that controlled for confounding demographic and socioeconomic variables such as age, sex, race, income, marriage status, insurance status, and highest education level.

MAIN OUTCOME MEASURES

NEI VFQ-25 Rasch scores compared with objective criteria diagnosis based on SAP mean deviation (MD) and SD-OCT retinal nerve fiber layer (RNFL) thickness.

RESULTS

Overall, eyes classified as normal, glaucoma suspect, and glaucoma had decreasing mean scores in SAP MD (0.2 ± 1.0 dB, -0.9 ± 2.4 dB, -6.2 ± 7.0 dB, respectively; P < 0.001) and SD-OCT RNFL thickness (97.8 ± 9.5 μm, 89.0 ± 13.1 μm, 64.5 ± 12.8 μm, respectively; P < 0.001). The mean Rasch-calibrated NEI VFQ-25 score was significantly different among normal, suspect, and glaucoma groups (82.9 ± 13.0, 78.2 ± 14.8, and 72.6 ± 16.2, respectively; P < 0.001). When adjusted for confounding socioeconomic variables, glaucoma patients had significantly worse QoL than those classified as normal (β = -6.8 Rasch score units; P < 0.001).

CONCLUSION

A glaucoma diagnosis, based on an objective reference standard for GON, was significantly associated with worse Rasch-adjusted scores of QoL. Utilization of such objective criteria may provide clinically relevant metrics with potential to improve comparability of research findings and validation of newly proposed diagnostic tools.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Association Between Ganglion Cell Complex Thinning and Vision-Related Quality of Life in Glaucoma

Importance

Faster structural changes may be associated with worse vision-related quality of life in patients with glaucoma.

Objectives

To evaluate the association between the rate of ganglion cell complex thinning and the Vision Function Questionnaire in glaucoma.

Design, Setting, and Participants

This retrospective analysis of a longitudinal cohort was designed in October 2021. Patients were enrolled from the Diagnostic Innovations in Glaucoma Study and the African Descent and Glaucoma Evaluation Study. Two hundred thirty-six eyes of 118 patients with diagnosed or suspected glaucoma were followed up with imaging for a mean of 4.1 years from September 2014 to March 2020.

Main Outcomes and Measures

The Vision Function Questionnaire was evaluated using the 25-item National Eye Institute Visual Function at the last follow-up visit. Ganglion cell complex thickness was derived from macular optical coherence tomography scans and averaged within 3 circular areas (3.4°, 5.6°, and 6.8° from the fovea) and superior and inferior hemiregions. Linear mixed-effects models were used to investigate the association between the rate of ganglion cell complex thinning and Rasch-calibrated Vision Function Questionnaire score.

Results

The mean (SD) age was 73.2 (8.7) years, 65 participants (55.1%) were female, and 53 participants (44.9%) were African American. Race was self-reported by the participants. Mean composite Rasch-calibrated National Eye Institute Visual Function Questionnaire score was 50.3 (95% CI, 45.9-54.6). A faster annual rate of global ganglion cell complex thinning in the better eye was associated with a higher disability reflected by the composite National Eye Institute Visual Function Questionnaire score (-15.0 [95% CI, -28.4 to -1.7] per 1 μm faster; P = .03). When stratified by degrees from the fovea, the 5.6° and 6.8° areas were associated with the composite National Eye Institute Visual Function Questionnaire Rasch-calibrated score (-14.5 [95% CI, -27.0 to -2.0] per 1 μm faster; R2 = 0.201; P = .03; and -23.7 [95% CI, -45.5 to -1.9] per 1 μm faster; R2 = 0.196; P = .02, respectively), and -8.0 (95% CI, -16.8 to 0.8) per 1 μm faster for the 3.4° area (R2 = 0.184; P = .07) after adjusting for confounding factors.

Conclusions and Relevance

These findings suggest that faster and sectoral central location of ganglion cell complex thinning provides useful information in determining the risk of vision-related quality of life in glaucoma. Monitoring macular structure may be useful for determining the risk of functional impairment in glaucoma.

A Review of Studies of the Association of Vision-Related Quality of Life with Measures of Visual Function and Structure in Patients with Glaucoma in the United States

Purpose: To investigate the association of quality of life (QoL) with ocular structure and function in glaucoma patients, and to identify which aspects of QoL are most closely tied to Visual Field (VF) and Visual Acuity (VA).Methods: We conducted a comprehensive review of studies on QoL in glaucoma patients using PubMed, Web of Science, and Google Scholar (from 1 January 1997 to 7 December 2019). A total of 21 studies in the United States that used the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ) or 51-item NEI VFQ were included. A descriptive analysis of data from the selected studies was conducted. The association between QoL scores and visual function and structure was investigated by ranking the strength of association on a scale from 1 (weakest) to 12 (strongest).Results: Studies reported correlations between QoL scores and Visual Structure. Associations were also reported between QoL and Visual Function both cross-sectionally and longitudinally, with a stronger association of VF and VA with distance activities (average ranking 9.1 and 9.6), vision-specific dependency (8.7 and 8.9), and driving (8.6 and 9.7). Vision-specific mental health (6.5 and 4.9), vision-specific social functioning (8.4 and 6.2), and vision-specific role difficulties (7.1 and 6.6) domains were more associated with VF than with VA.Conclusion: Our study was the first to quantify and rank the strength of association between visual function and QoL domains. Driving and psycho-social QoL domains tended to be most affected by glaucoma-related deterioration of visual function. QoL scores could be used for more patient-centered disease management.

Beyond intraocular pressure: Optimizing patient-reported outcomes in glaucoma

Glaucoma, an irreversible blinding condition affecting 3-4% adults aged above 40 years worldwide, is set to increase with a rapidly aging global population. Raised intraocular pressure (IOP) is a major risk factor for glaucoma where the treatment paradigm is focused on managing IOP using medications, laser, or surgery regimens. However, notwithstanding IOP and other clinical parameters, patient-reported outcomes, including daily functioning, emotional well-being, symptoms, mobility, and social life, remain the foremost concerns for people being treated for glaucoma. These outcomes are measured using objective patient-centered outcome measures (PCOMs) and subjective patient-reported outcome measures (PROMs). Studies using PCOMs have shown that people with glaucoma have several mobility, navigational and coordination challenges; reading and face recognition deficits; and are slower in adapting to multiple real-world situations when compared to healthy controls. Similarly, studies have consistently demonstrated, using PROMs, that glaucoma substantially and negatively impacts on peoples' self-reported visual functioning, mobility, independence, emotional well-being, self-image, and confidence in healthcare, compared to healthy individuals, particularly in those with late-stage disease undergoing a heavy treatment regimen. The patient-centred effectiveness of current glaucoma treatment paradigms is equivocal due to a lack of well-designed randomized controlled trials; short post-treatment follow-up periods; an inappropriate selection or availability of PROMs; and/or an insensitivity of currently available PROMs to monitor changes especially in patients with newly diagnosed early-stage glaucoma. We provide a comprehensive, albeit non-systematic, critique of the psychometric properties, limitations, and recent advances of currently available glaucoma-specific PCOMs and PROMs. Finally, we propose that item banking and computerized adaptive testing methods can address the multiple limitations of paper-pencil PROMs; customize their administration; and have the potential to improve healthcare outcomes for people with glaucoma.

Improving the Feasibility of Glaucoma Clinical Trials Using Trend-Based Visual Field Progression Endpoints

Purpose

There have been concerns that short-term clinical trials for evaluating new treatments in glaucoma would require prohibitively large sample sizes when using visual field endpoints, given that glaucoma is often a slowly progressive disease. This study sought to determine the required sample size for such trials using event-based analyses, and whether it can be reduced using trend-based analyses.

Design

Longitudinal, observational study.

Participants

321 eyes of 240 glaucoma participants followed under routine clinical care using 242 visual field for an average of 10 years.

Methods

Sample size requirements were derived using computer simulations that reconstructed "real-world" visual fields by combining estimates of point-wise variability according to different threshold levels and rates of change obtained from the clinical glaucoma cohort. A clinical trial lasting 2 years with testing every 3 months was simulated, assuming that the new treatment halted visual field change in various percentages of participants (or "responders"). Treatment efficacy was evaluated by: (a) Difference in incidence of point-wise event-based progression (similar to the commercially available Guided Progression Analysis), and (b) Difference in rate of visual field mean deviation (MD) change between groups using linear mixed models (LMMs).

Main Outcome Measures

Sample size to detect a statistically significance difference between groups.

Results

Between-group trend-based analyses using LMMs reduced sample size requirements by 85-90% across the range of new treatment effects when compared to the conventional point-wise event-based analysis. To detect the effect of a new treatment that halted progression in 30% of the participants under routine clinical care (equal to a 30% reduction in average rate of MD change) with 90% power, for example, 1924 participants would be required per group using event-based analysis, but only 277 participants per group if LMMs were used.

Conclusions

The feasibility of future glaucoma clinical trials can be substantially improved by evaluating differences in the rate of visual field change between groups.

What Is the Amount of Visual Field Loss Associated With Disability in Glaucoma?

PURPOSE

To propose a new methodology for classifying patient-reported outcomes in glaucoma and for quantifying the amount of visual field damage associated with disability in the disease.

DESIGN

Cross-sectional study.

METHODS

A total of 263 patients with glaucoma were included. Vision-related disability was assessed by the National Eye Institute Visual Function Questionnaire (NEI VFQ-25). A latent class analysis (LCA) model was applied to analyze NEI VFQ-25 data and patients were divided into mutually exclusive classes according to their responses to the questionnaires. Differences in standard automated perimetry (SAP) mean deviation (MD) and integrated binocular mean sensitivity (MS) values between classes were investigated. The optimal number of classes was defined based on goodness-of-fit criteria, interpretability, and clinical utility.

RESULTS

The model with 2 classes, disabled and nondisabled, had the best fit with an entropy of 0.965, indicating excellent separation of classes. The disabled group had 48 (18%) patients, whereas 215 (82%) patients were classified as nondisabled. The average MD of the better eye in the disabled group was -5.98 dB vs -2.51 dB in the nondisabled group (P < .001). For the worse eye, corresponding values were -13.36 dB and -6.05 dB, respectively (P < .001).

CONCLUSION

Application of an LCA model allowed categorization of patient-reported outcomes and quantification of visual field levels associated with disability in glaucoma. A damage of approximately -6 dB for SAP MD, indicating relatively early visual field loss, may already be associated with significant disability if occurring in the better eye.

Comparison of Visual Field Point-Wise Event-Based and Global Trend-Based Analysis for Detecting Glaucomatous Progression

Purpose

To compare global trend-based and point-wise event-based analysis for detecting visual field progression in eyes with glaucoma.

Methods

The study included a cohort of 367 glaucoma eyes from 265 participants seen over a mean follow-up period of 10 years to develop a computer simulation model of "real-world" visual field results. Progression was evaluated with point-wise event-based analysis using the Guided Progression Analysis (GPA) and global trend-based analysis using the mean deviation (MD) and visual field index (VFI) measures. The specificities of the methods were matched based on a simulated dataset of stable glaucoma eyes, to allow an adequate comparison of their sensitivities for detecting progression.

Results

The 5-year cumulative false-positive rate for the GPA alert of "possible progression" and "likely progression" (significant change from baseline at two and three consecutive visits, respectively) were 34.0% and 7.0%, respectively. At matched specificities, 27.7% eyes were detected as having progressed after 5 years using the GPA "likely progression" criterion, while 24.6% and 23.8% were detected as having progressed using the global trend-based analysis with MD and VFI, respectively. There was a moderate level of agreement between the GPA and global trend-based analyses.

Conclusions

Pointwise event-based and global trend-based methods had similar performances to detect glaucoma progression when rigorously matched for specificity.

Translational Relevance

Although both point-wise event- and global trend-based analyses perform similarly, they could provide complementary information that could be exploited to improve the overall detection of progression in clinical practice and clinical trials.

Impact of Different Visual Field Testing Paradigms on Sample Size Requirements for Glaucoma Clinical Trials

Visual field testing is an important endpoint in glaucoma clinical trials, and the testing paradigm used can have a significant impact on the sample size requirements. To investigate this, this study included 353 eyes of 247 glaucoma patients seen over a 3-year period to extract real-world visual field rates of change and variability estimates to provide sample size estimates from computer simulations. The clinical trial scenario assumed that a new treatment was added to one of two groups that were both under routine clinical care, with various treatment effects examined. Three different visual field testing paradigms were evaluated: a) evenly spaced testing, b) United Kingdom Glaucoma Treatment Study (UKGTS) follow-up scheme, which adds clustered tests at the beginning and end of follow-up in addition to evenly spaced testing, and c) clustered testing paradigm, with clusters of tests at the beginning and end of the trial period and two intermediary visits. The sample size requirements were reduced by 17–19% and 39–40% using the UKGTS and clustered testing paradigms, respectively, when compared to the evenly spaced approach. These findings highlight how the clustered testing paradigm can substantially reduce sample size requirements and improve the feasibility of future glaucoma clinical trials.

Predicting the Integrated Visual Field with Wide-Scan Optical Coherence Tomography in Glaucoma Patients

PURPOSE

This study aimed to calculate a predicted integrated visual field (IVF) based on predicted monocular visual fields (MVFs) derived, with a new method, from wide-scan optical coherence tomography (OCT) data.

MATERIALS AND METHODS

Visual field testing used the central (6 × 4) 24 points of the Humphrey Field Analyzer 24-2 program. OCT scans of a corresponding retinal area, centered on the fovea, were divided into a 6 × 4 grid. The thickness of the macular retinal nerve fiber layer (mRNFL), ganglion cell layer + inner plexiform layer (GCIPL), and mRNFL + GCIPL (GCC) was measured in each grid area. Next, a support vector machine was used to create a MVF prediction model, with training data from 101 eyes of 60 glaucoma patients. Then, the prediction model was validated with data from 108 eyes of 54 glaucoma patients, for MVF and IVF. A simulated IVF was created by merging bilateral simulated MVFs.

RESULTS

The overall average of the median 95% prediction interval length for the MVF prediction model (measured in dB) was 10.0, 18.3, and 11.3 for the mRNFL, GCIPL, and GCC, respectively. In the validation data, the overall average root mean squared error (dB) between actual and predicted sensitivity for the IVF was 9.6, 10.5, and 9.5 for the mRNFL, GCIPL, and GCC, respectively, in the 24 grid areas. The intraclass correlation coefficient between average actual and predicted IVF was 0.61, 0.44, and 0.59 in the mRNFL, GCIPL, and GCC, respectively, in the 24 grid areas.

CONCLUSIONS

We calculated a predicted IVF based on predicted MVFs that were derived, with a new method, from OCT data and validated the accuracy of the calculated IVF. This technique should improve glaucoma management in cases when standard visual field testing is difficult.

Predicting Vision-Related Disability in Glaucoma

PURPOSE

To present a new methodology for investigating predictive factors associated with development of vision-related disability in glaucoma.

DESIGN

Prospective, observational cohort study.

PARTICIPANTS

Two hundred thirty-six patients with glaucoma followed up for an average of 4.3±1.5 years.

METHODS

Vision-related disability was assessed by the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) at baseline and at the end of follow-up. A latent transition analysis model was used to categorize NEI VFQ-25 results and to estimate the probability of developing vision-related disability during follow-up. Patients were tested with standard automated perimetry (SAP) at 6-month intervals, and evaluation of rates of visual field change was performed using mean sensitivity (MS) of the integrated binocular visual field. Baseline disease severity, rate of visual field loss, and duration of follow-up were investigated as predictive factors for development of disability during follow-up.

MAIN OUTCOME MEASURES

The relationship between baseline and rates of visual field deterioration and the probability of vision-related disability developing during follow-up.

RESULTS

At baseline, 67 of 236 (28%) glaucoma patients were classified as disabled based on NEI VFQ-25 results, whereas 169 (72%) were classified as nondisabled. Patients classified as nondisabled at baseline had 14.2% probability of disability developing during follow-up. Rates of visual field loss as estimated by integrated binocular MS were almost 4 times faster for those in whom disability developed versus those in whom it did not (-0.78±1.00 dB/year vs. -0.20±0.47 dB/year, respectively; P < 0.001). In the multivariate model, each 1-dB lower baseline binocular MS was associated with 34% higher odds of disability developing over time (odds ratio [OR], 1.34; 95% confidence interval [CI], 1.06-1.70; P = 0.013). In addition, each 0.5-dB/year faster rate of loss of binocular MS during follow-up was associated with a more than 3.5 times increase in the risk of disability developing (OR, 3.58; 95% CI, 1.56-8.23; P = 0.003).

CONCLUSIONS

A new methodology for classification and analysis of change in patient-reported quality-of-life outcomes allowed construction of models for predicting vision-related disability in glaucoma.

Fast Visual Field Progression Is Associated with Depressive Symptoms in Patients with Glaucoma

PURPOSE

To evaluate the association between the rates of progressive visual field loss and the occurrence of depressive symptoms in patients with glaucoma followed over time.

DESIGN

Prospective observational cohort study.

PARTICIPANTS

The study included 204 eyes of 102 patients with glaucomatous visual field defects on standard automated perimetry (SAP).

METHODS

All patients had Geriatric Depression Scale (GDS) questionnaires and visual field tests obtained over a mean follow-up time of 2.2±0.6 years. Change in depressive symptoms was assessed by calculating the difference between GDS scores at the last follow-up visit from those at baseline. Rates of visual field loss were assessed by SAP. An integrated binocular visual field was estimated from the monocular SAP tests, and rates of change in mean sensitivity (MS) over time were obtained from linear mixed models. Regression models were used to investigate the association between progressive visual field loss and changes in depressive symptoms, adjusting for potentially confounding clinical and socioeconomic variables.

MAIN OUTCOME MEASURES

The association between rates of change in binocular SAP MS and change in GDS questionnaire scores.

RESULTS

There was a significant correlation between change in the GDS scores during follow-up and change in binocular SAP sensitivity. Each 1 decibel (dB)/year change in binocular SAP MS was associated with a change of 2.0 units in the GDS scores during the follow-up period (P = 0.025). In a multivariable model adjusting for baseline disease severity, change in visual acuity, age, gender, race, Montreal Cognitive Assessment score, education, income, and comorbidity index, each 1 dB/year change in binocular SAP MS was associated with a change of 3.0 units in the GDS score (P = 0.019).

CONCLUSIONS

Faster visual field progression was associated with the occurrence of depressive symptoms in patients with glaucoma.