A glaucoma equity profile: correlating disease distribution with service provision and uptake in a population in Northern England, UK

Differentiating stages of functional vision loss from glaucoma using the Disc Damage Likelihood Scale and cup:disc ratio

BACKGROUND

Glaucoma staging is critical for treatment planning but has rarely been tested in severe/end-stage disease. We compared the performance of the Disc Damage Likelihood Scale (DDLS) and cup:disc ratio (CDR) using a functional glaucoma staging system (GSS) as the reference standard.

METHODS

Post hoc analysis of a randomised controlled trial at the Eye Department of Kilimanjaro Christian Medical Centre, Tanzania. Eligible participants (aged ≥18 years) with open-angle glaucoma, intraocular pressure (IOP) of >21 mm Hg, were randomised to timolol 0.5% eye drops or selective laser trabeculoplasty. Fundoscopy established vertical and horizontal CDRs and DDLS. Visual acuity and static visual fields were graded (GSS). The study used area under the receiver operating characteristic (AROC) curves and Spearman's rank correlation coefficients to compare staging systems. Logistic regression with generalised estimating equations determined risk factors of functional severe/end-stage glaucoma.

RESULTS

382 eyes (201 participants) were evaluated; 195 (51%) had severe or end-stage glaucoma; mean IOP was 26.7 (SD 6.9) mm Hg. DDLS yielded an AROC of 0.90 (95% CI 0.87 to 0.93), vertical cup:disc ratio (vCDR) of 0.88 (95% CI 0.85 to 0.91, p=0.048) for identifying severe/end-stage disease. Correlation coefficients comparing GSS to DDLS and vCDRs were 0.73 and 0.71, respectively. Advanced structural stages, vision impairment, higher IOP and less financial resources were risk factors of functional severe/end-stage glaucoma.

CONCLUSION

This study indicates that both structural staging systems can differentiate severe/end-stage glaucoma from less severe disease, with a moderate advantage of DDLS over CDR. Clinical examination of the optic disc plays an important role in addition to functional assessment when managing severe/end-stage glaucoma.

Measures of multiple deprivation and visual field loss in glaucoma clinics in England: lessons from big data

BACKGROUND/OBJECTIVES

To examine the association between multiple deprivation with late diagnosis and rapid worsening of glaucoma in patients in English hospital eye services (HES).

METHODS

602,439 visual fields (VFs) were extracted from five regionally different glaucoma clinics in England. Mean Deviation (MD) worse than -12 dB was used as a surrogate definition for advanced VF loss at diagnosis in patients with ≥2 reliable VF records. MD loss worse than -1 dB per year was used to define rapid VF progression in patients with ≥6 VFs. Patient data were stratified into deciles of the Index of Multiple Deprivation (IMD) from residential postcodes.

RESULTS

There was an association between IMD and advanced VF loss at diagnosis in 44,956 patients with 18% (293/1608) and 11% (771/6929) in the most and least deprived IMD decile, respectively. Age-corrected odds ratio (OR) for having advanced VF loss at entry into HES was 1.42 (95% confidence interval [CI] 1.21-1.67) and 0.75 (95% CI: 0.66-0.85) in the most and least deprived IMD decile respectively (reference = fifth decile). In 15,094 patients with follow up data (median [interquartile range] of 6.9 [4.5, 10.0] years), the proportion having rapid VF progression did not differ across the IMD spectrum.

CONCLUSION

Large-scale VF data from clinics indicates that glaucoma severity at presentation to English HES is associated with levels of multiple deprivation. We found no evidence to suggest likelihood of having rapid VF progression during follow-up is associated with IMD; this hints at equity of glaucoma care and outcomes once patients are in English HES.

Socio-economic differences in accessing NHS spectacles amongst children with differing refractive errors living in Scotland

BACKGROUND/OBJECTIVES

Adults living in more deprived areas are less likely to attend an eye examination, resulting in greater visual impairment from undiagnosed eye disease and a widening of health inequalities. It is unknown if the introduction of free NHS eye examinations and help with spectacle costs has benefited children in Scotland. This study aimed to explore factors associated with accessing NHS spectacles including level of deprivation, refractive error, urbanity and age.

SUBJECTS/METHODS

NHS-financed General Ophthalmic Services (GOS) 3 supplement the cost of spectacles for children under 16 years. Administrative data on the spectacle refraction dispensed were obtained from Information Services Division (ISD) for mainland Scotland, 2018, and categorised by: Emmetropes/low hyperopes (reference group), myopes and moderate/high hyperopes. Data were linked to the Scottish Index of Multiple Deprivation (SIMD) quintile.

RESULTS

Data included 108, 043 GOS 3 claims. Greater deprivation was associated with greater GOS 3 claims p = 0.041. This was most evident in emmetropic/low hyperopic children and in moderate/high hyperopic children. GOS 3 claims in the myopes group increased with age across all SIMD and decreased with age in the moderate/high hyperope group (all p < 0.001). GOS 3 claims were not associated with urbanity for all Health Boards (p = 0.13).

CONCLUSIONS

Children in areas of greater deprivation and in more rural areas are not disadvantaged in accessing NHS spectacles. This did not vary by refractive error group. This suggests that health policy in Scotland is accessible to those from all deprivation levels and refractive errors.

The Global Extent of Undetected Glaucoma in Adults: A Systematic Review and Meta-analysis

TOPIC

Glaucoma is the leading cause of irreversible blindness, despite having good prognosis with early treatment. We evaluated the global extent of undetected glaucoma and the factors associated with it in this systematic review and meta-analysis.

CLINICAL RELEVANCE

Undetected glaucoma increases the risk of vision impairment, which leads to detrimental effects on the quality-of-life and socioeconomic well-being of those affected. Detailed information on the extent and factors associated with undetected glaucoma aid in the development of public health interventions.

METHODS

We conducted a systematic review and meta-analysis of population-based studies published between January 1, 1990, and June 1, 2020. Article search was conducted in online databases (PubMED, Web-of-Science), grey literatures (OpenGrey), and nongovernment organization reports. Our outcome measure was the proportion of glaucoma cases that were undetected previously. Manifest glaucoma included any form of glaucoma reported in the original studies and may include primary open-angle glaucoma (POAG), primary angle-closure-glaucoma, secondary glaucoma, or a combination thereof. Undetected glaucoma was defined as glaucoma cases that were undetected prior to diagnosis in the respective study. Random-effect meta-analysis was used to estimate the pooled proportion of undetected glaucoma. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the Meta-analysis of Observational Studies in Epidemiology guidelines in our study.

RESULTS

We identified 61 articles from 55 population-based studies (n = 189 359 participants; n = 6949 manifest glaucoma). Globally, more than half of all glaucoma cases were undetected previously on average in each geographical region. Africa (odds ratio [OR], 12.70; 95% confidence interval [CI], 4.91-32.86) and Asia (OR, 3.41; 95% CI, 1.63-7.16) showed higher odds of undetected glaucoma as compared with Europe. Countries with low Human Development Index (HDI; <0.55) showed a higher proportion of undetected manifest glaucoma as compared with countries of medium to very high HDI (≥0.55; all P < 0.001). In 2020, 43.78 million POAG cases were projected to be undetected, of which 76.7% were in Africa and Asia.

DISCUSSION

Undetected glaucoma is highly prevalent across diverse communities worldwide and more common in Africa and Asia. Strategies to improve detection are needed to prevent excess visual disability and blindness resulting from glaucoma.

Exploring the effect of optometrist practice type on NHS funded sight test outcome

PURPOSE

The United Kingdom (UK) National Health Service (NHS) currently provides sight tests at no cost to patients for all those aged <16 or ≥60. Some 'at-risk' patients and those in receipt of means-tested benefits are eligible for a NHS sight test between the ages of 16 and 60. In the UK, community optometrists typically either work in independent or national chain practices (multiples). The present study aims to explore whether practice type has any association with sight test outcome. As sight tests are essential in detecting early childhood visual problems, we also aim to explore children's first sight tests.

METHOD

Data from 664,480 NHS sight test claims submitted in Essex from April 2015 to September 2016 were analysed using regression analysis. Practice type (multiple, independent) and children's first sight test were examined with respect to socio-economic status (SES, based on index of multiple deprivation rankings), age and sight test outcome.

RESULTS

The median age for a first NHS sight test was 6 years old and was clinically independent of SES. Children's first sight tests typically resulted in neither a spectacle prescription being issued nor an onwards referral. Patients that attend multiples are significantly more likely to receive a new prescription, relative to no prescription, compared to a patient attending an independent (p<.001).

CONCLUSIONS

Inequalities in sight test outcome appear to exist with differing type of practice (independent or multiple). Choice of practice type appears to be influenced by SES. Children have their first sight test at a later age than recommended.

Geographical inequalities in uptake of NHS funded eye examinations: Poisson modelling of small-area data for Essex, UK

Background

Small-area analysis of National Health Service (NHS)-funded sight test uptake in Leeds showed significant inequalities in access among people aged <16 or ≥60.

Methods

Data were extracted from 604 126 valid General Ophthalmic Services (GOS)1 claim forms for eye examinations for Essex residents between October 2013 and July 2015. Expected GOS1 uptake for each lower super output area was based on England annual uptake. Poisson regression modelling explored associations in GOS1 uptake ratio with deprivation.

Results

People aged ≥60 or <16 living in the least deprived quintile were 15% and 26%, respectively, more likely to have an NHS funded eye examination than the most deprived quintile, although all are equally entitled. GOS1 uptake is higher in the more deprived quintiles among 16-59-year old, as means tested social benefits are the main eligibility criteria in this age-group. Inequalities were also observed at local authority level.

Conclusions

Inequalities in access among people ≥60 years were not as large as those reported in Leeds, although inequalities in <16-year old were similar. However, demonstrable inequalities in this data set over a longer time period and a larger and more diverse area than Leeds, reinforce the argument that interventions are needed to address eye examination uptake inequalities.

Distribution of optometric practices relative to deprivation index in Scotland

Background

The UK National Health Service aims to provide universal availability of healthcare, and eye-care availability was a primary driver in the development of the Scottish General Ophthalmic Services (GOS) model. Accordingly, a relatively equal distribution of optometry practices across socio-economic areas is required. We examined practice distribution relative to deprivation.

Methods

672 practices were sampled from nine Health Boards within Scotland. Practices were assigned a deprivation ranking by referencing their postcode with the Scottish Index of Multiple Deprivation (SIMD) tool (Scottish Executive National Statistics: General Report. 2016).

Results

Averaged across Health Boards, the share of practices for the five deprivation quintiles was 25, 33, 18, 14 and 11% from most to least deprived area, respectively. Although there was some variation of relative practice distribution in individual Health Boards, 17 of the 45 regions (nine Health Boards, five quintiles) had a close balance between population and share of practices. There was no clear pattern of practice distribution as a function of deprivation rank. Analysis revealed good correlation between practice and population share for each Health Board, and for the combined data (R² = 0.898, P < 0.01).

Conclusion

Distribution of optometry practices is relatively balanced across socio-economic areas, suggesting that differences in eye-examination uptake across social strata are unrelated to service availability.

Health Inequalities Associated with Post-Stroke Visual Impairment in the United Kingdom and Ireland: A Systematic Review

The aim of this study was to report on the health inequalities facing stroke survivors with visual impairments as described in the current literature. A systemic review of the literature was conducted to investigate the potential health inequalities facing stroke survivors with subsequent visual impairments. A quality-of-evidence and risk-of-bias assessment was conducted for each of the included articles using the appropriate tool dependent on the type of article. Only four articles discussed health inequalities affecting stroke survivors with visual impairment specifically. A further 23 articles identified health inequalities after stroke, and 38 reported on health inequalities within the visually impaired UK or Irish population. Stroke survivors with visual impairment face inconsistency in eye care provision nationally, along with variability in the assessment and management of visual disorders. The subgroups identified as most at risk were females; black ethnicity; lower socioeconomic status; older age; and those with lower education attainment. The issue of inconsistent service provision for this population must be addressed in future research. Further research must be conducted in order to firmly establish whether or not stroke survivors are at risk of the aforementioned sociodemographic and economic inequalities.

Geographical variation in glaucoma prescribing trends in England 2008-2012: an observational ecological study

OBJECTIVES

To explore (1) the national trend in population-adjusted prescription rates for glaucoma and ocular hypertension (OHT) in England and (2) any geographical variation in glaucoma/OHT prescribing trends and its association with established risk factors for primary open-angle glaucoma (POAG) at the population level.

DESIGN

Observational ecological study.

SETTING

Primary care in England 2008-2012.

PARTICIPANTS

All patients who received 1 or more of the 37 778 660 glaucoma/OHT prescription items between 2008 and 2012.

PRIMARY AND SECONDARY OUTCOME MEASURE METHODS

Glaucoma/OHT prescription statistics for England and its constituent primary care trusts (PCTs) between 2008 and 2012 were divided by annual population estimates to give prescription rates per 100 000 population aged ≥40 years. To examine regional differences, prescription rates and the change in prescription rates between 2008 and 2012 for PCTs were separately entered into multivariable linear regression models with the population proportion aged ≥60 years; the proportion of males; the proportion of West African Diaspora (WAD) ethnicity; PCT funding per capita; Index of Multiple Deprivation 2010 score and its domains.

RESULTS

Between 2008 and 2012, glaucoma/OHT prescriptions increased from 28 029 to 31 309 items per 100 000 population aged ≥40 years. Between PCTs, nearly a quarter of the variation in prescription rates in 2008 and 2012 could be attributed to age, WAD ethnicity and male gender. The change in prescription rates between 2008 and 2012 was only modestly correlated with age (p=0.003, β=0.234), and income deprivation (p=0.035, β=-0.168).

CONCLUSIONS

Increased population-adjusted glaucoma/OHT prescription rates in the study period were likely due to increased detection of POAG and OHT cases at risk of POAG. Between PCTs, regional variation in overall prescription rates was partly attributable to demographic risk factors for POAG, although the change in prescription rates was only modestly correlated with the same risk factors, suggesting potential variation in practice.

Measures of socioeconomic status and self-reported glaucoma in the U.K. Biobank cohort

PURPOSE

To determine ocular, demographic, and socioeconomic associations with self-reported glaucoma in the U.K. Biobank.

METHODS

Biobank is a study of U.K. residents aged 40-69 years registered with the National Health Service. Data were collected on visual acuity, intraocular pressure (IOP), corneal biomechanics, and questionnaire from 112,690 participants. Relationships between ocular, demographic, and socioeconomic variables with reported diagnosis of glaucoma were examined.

RESULTS

In all, 1916 (1.7%) people in U.K. Biobank reported glaucoma diagnosis. Participants reporting glaucoma were more likely to be older (mean 61.4 vs. 56.7 years, P<0.001) and male (2.1% vs. 1.4%, P=0.001). The rate of reported glaucoma was significantly higher in Black (3.28%, P<0.001) and Asian (2.14%, P=0.009) participants compared with White participants (1.62%, reference). Cases of reported glaucoma had a higher mean IOP (18 mm Hg both eyes, P<0.001), lower corneal hysteresis (9.96 right eye, 9.89 left eye, P<0.001), and lower visual acuity (0.09 logMAR right eye, 0.08 logMAR left eye, P<0.001) compared with those without (16 mm Hg both eyes, hysteresis 10.67 right eye, 10.63 left eye, 0.03 logMAR right eye, 0.02 logMAR left eye). The mean Townsend deprivation index was -0.72 for those reporting glaucoma and -0.95 for those without (P<0.001), indicating greater relative deprivation in those reporting glaucoma. Multivariable logistic regression showed that people in the lowest income group (<£18,000/year) were significantly more likely to report a diagnosis of glaucoma compared with any other income level (P<0.01). We observed increasing glaucoma risk across the full range of income categories, with highest risk among those of lowest income, and no evidence of a threshold effect.

CONCLUSIONS

In a large U.K. cohort, individuals reporting glaucoma had more adverse socioeconomic characteristics. Study of the mechanisms explaining these effects may aid our understanding of health inequality and will help inform public health interventions.

Area deprivation and age related macular degeneration in the EPIC-Norfolk Eye Study

Objectives

To investigate the relationship between area deprivation, individual socio-economic status (SES) and age related macular degeneration (AMD).

Study design

Cross sectional study nested within a longitudinal cohort study.

Methods

Data were collected in the EPIC-Norfolk Eye Study by trained nurses, using standardized protocols and lifestyle questionnaires. The English Index of multiple deprivation 2010 (IMD) was derived from participants' postcodes. AMD was identified from standardized grading of fundus photographs. Logistic regression was used to examine associations between IMD, SES and AMD.

Results

5344 pairs (62.0% of total 8623) of fundus photographs were of sufficient quality for grading of AMD. Of 5182 participants with complete data, AMD was identified in 653 participants (12.60%, 95%CI = 11.7–13.5%). Multivariable logistic regression showed that people living in the most affluent 5% of areas had nearly half the odds of AMD compared to those living in comparatively more deprived areas (OR = 0.56, 95% CI = 0.36–0.89, P = 0.02), after adjusting for age, sex, education, social class and smoking.

Conclusions

The authors found that living in the most affluent areas exerted a protective effect on AMD, independently of education and social class. Further investigation into underlying mechanisms will inform potential interventions to reduce health inequalities relating to AMD.

•

The relationship between area deprivation and AMD diagnosed from fundus photographs was examined.

•

Data from 5182 participants from the EPIC-Norfolk Eye study were analyzed.

•

Predominantly early AMD was identified in 653 participants (12.6%).

•

People living in more affluent areas had nearly half the risk of AMD.

•

Results require interpretation with caution due to the healthy population studied.

The relationship between socio-economic status and access to eye health services in the UK: a systematic review

OBJECTIVES

Lower socio-economic status has been shown to adversely affect access to general health care. This study aims to determine the existence and nature of an association between socio-economic status and access to eye health services in the UK.

STUDY DESIGN

Systematic review.

METHODS

Search terms were run in four databases and reviewed against a pre-agreed set of inclusion and exclusion criteria by two independent reviewers. Quality of studies was assessed according to calculations of statistical significance, size of effect, primary research question and a quality score against an adapted STROBE checklist.

RESULTS

Good quality studies included in the review most commonly concluded that lower socio-economic groups had less access to eye health services than higher socio-economic groups. However there were a comparable number of studies that concluded that there was no association. This discrepancy was largely attributed to different ways of measuring socio-economic status, access, and types of eye health services, and so studies did not compare the same thing. The evidence base was of low quality, limiting the ability of this review to make definitive conclusions.

CONCLUSIONS

The review concluded that there is equal and weak evidence of lower socio-economic groups having reduced access to eye health services in the UK, and there being no association. This subject would benefit from further research to improve the quality of the evidence base.

Addressing inequalities in eye health with subsidies and increased fees for General Ophthalmic Services in socio-economically deprived communities: a sensitivity analysis

OBJECTIVES

Poor knowledge of eye health, concerns about the cost of spectacles, mistrust of optometrists and limited geographical access in socio-economically deprived areas are barriers to accessing regular eye examinations and result in low uptake and subsequent late presentation to ophthalmology clinics. Personal Medical Services (PMS) were introduced in the late 1990 s to provide locally negotiated solutions to problems associated with inequalities in access to primary care. An equivalent approach to delivery of optometric services could address inequalities in the uptake of eye examinations.

STUDY DESIGN

One-way and multiway sensitivity analyses.

METHODS

Variations in assumptions were included in the models for equipment and accommodation costs, uptake and length of appointments. The sensitivity analyses thresholds were cost-per-person tested below the GOS1 fee paid by the NHS and achieving break-even between income and expenditure, assuming no cross-subsidy from profits from sales of optical appliances.

RESULTS

Cost per test ranged from £ 24.01 to £ 64.80 and subsidy required varied from £ 14,490 to £ 108,046. Unused capacity utilised for local enhanced service schemes such as glaucoma referral refinement reduced the subsidy needed.

CONCLUSIONS

In order to support the financial viability of primary eye care in socio-economically deprived communities, income is required from additional subsidies or from sources other than eye examinations, such as ophthalmic or other optometric community services. This would require a significant shift of activity from secondary to primary care locations. The subsidy required could also be justified by the utility gain from earlier detection of preventable sight loss.

Geographical inequalities in uptake of NHS-funded eye examinations: small area analysis of Leeds, UK

BACKGROUND

Preventable sight loss is an indicator within the Public Health Outcome Framework 2013-2018 for England. Routinely available optometric data do not permit small area analysis of access inequalities.

METHODS

Data were extracted from 17 680 General Ophthalmic Services (GOS1) claim forms for eye examinations conducted in Leeds during February and March 2011. The expected number of GOS1 uptake for each lower super output area was based on the GOS1 national annual uptake. A Poisson regression model was used to explore associations in the GOS1 uptake ratio with deprivation and gender.

RESULTS

People aged 60 or over or under 16 living in the least deprived quintile are 71 and 23%, respectively, more likely to have an NHS-funded eye examination than someone in that age group in the most deprived quintile, although all are equally entitled. Uptake is higher in the more deprived quintiles among 16-59 year olds, as means tested social benefits are the main eligibility criteria in this age group. There were no statistically significant gender differences in uptake.

CONCLUSIONS

Interventions are needed to address eye examination uptake inequalities. However, in order to better inform commissioning and planning eye care services more complete data with additional detail are required. GOS1 forms ought to be submitted electronically linked to additional demographic and clinical data to allow public health analysis. Ideally, private eye examination data should also be captured.

Improving access to optometry services for people at risk of preventable sight loss: a qualitative study in five UK locations

Background

Reducing preventable sight loss is an increasing priority for public health and health care providers. We examined the factors affecting people's use of optometry services in population groups at increased risk of sight loss.

Methods

This is a qualitative study in five UK locations. In England, participants were from the Pakistani and Black Caribbean communities; in Scotland from the Pakistani community; and in Northern Ireland and Wales from white socio-economically deprived communities. Thirty-four focus groups were conducted (n = 289). The study included people who attend optometry services and people not engaged with services.

Results

Barriers to access included limited awareness of eye health and eye disease, concern about the cost of spectacles and the appropriateness of optometry in a commercial setting. Attendance at the optometrist was primarily symptom led. A positive previous experience or continuing relationship with the optometrist helped to alleviate the barriers and promote attendance.

Conclusion

Addressing the disparity between the broader messages about eye health and the current perception of the function of optometry could help improve access to services. Uptake may be improved through the co-production of interventions that better resonate with local communities. Non-retail service delivery options should be explored.

Area deprivation, individual socioeconomic status and low vision in the EPIC-Norfolk Eye Study

Background

Poor vision is associated with lower socioeconomic status, but less is known about its relationship to area deprivation.

Methods

The European Prospective Investigation into Cancer and Nutrition study Norfolk Eye Study was a cross-sectional study of 8563 participants with completed eye examinations. Logarithm of the minimum angle of resolution (logMAR) visual acuity (VA) was measured using standard protocols and low vision (LV) was defined as Snellen equivalent (VA) ≤6/12 in the better eye. Uncorrected refractive error (URE) was defined as improvement of VA by 2 logarithm of the minimum angle of resolution lines with pinhole. The lowest 5% of index of multiple deprivation rank was used to define the most deprived areas. The index of multiple deprivation is a composite measure using routine data from seven domains of deprivation to identify the most disadvantaged areas in England. Logistic regression was used to examine univariable and multivariable associations with LV.

Results

Ninety-six participants with missing data were excluded, leaving 8467 for analysis (98.9%). The mean age of the study group was 68.7 years (SD=8.1, range=48–92), with 55.1% women. LV was present in 263 participants (3.1%, 95% CI 2.7 to 3.5%). LV was associated with deprivation after adjusting for age, sex, education, social class and cataract surgery (OR=1.7, 95% CI 1.1 to 2.6, p=0.03), but this effect was mitigated by additionally adjusting for URE (OR=1.5, 95% CI 1.0 to 2.4, p=0.09).

Conclusions

People with LV are more likely to live in the most deprived areas; this association was independent of socioeconomic status and partly mediated by URE. Targeting URE in deprived areas may reduce health inequalities associated with LV.