Effect of Community Screening on the Demographic Makeup and Clinical Severity of Glaucoma Patients Receiving Care in Urban China

Association Between Sociodemographic Factors and Self-reported Glaucoma in the National Health Interview Survey: A Population-Based Analysis

PURPOSE

To investigate the association between social determinants of health (SDH) in the domains of social and community context, education access, environmental context, economic stability, and healthcare access, with glaucoma prevalence.

DESIGN

Cross-sectional study.

METHODS

The study population consisted of adult participants who answered glaucoma-related questions on the 2017 National Health Interview Survey (NHIS), the most recent iteration that includes glaucoma-related questions. The main outcome measures included the relationships between SDH-related factors and self-reported glaucoma diagnosis as well as self-reported glaucomatous vision loss were examined using univariable and multivariable regression models.

RESULTS

In total, 26,696 of 26,742 (99.83%) NHIS respondents were included, of whom 880 (3.30%) reported a glaucoma diagnosis and 275 (1.03%) reported glaucomatous vision loss. Participants were predominantly middle-aged (50.95 ± 18.60 years), female (54.75%), and non-Hispanic White (70.49%). In age-adjusted multivariable regression (n = 25,456), non-Hispanic Black race (odds ratio [OR] = 1.87, 99% CI = [1.37, 2.55], P < .001, compared to non-Hispanic White race) and poor health status (OR = 1.54, 99% CI = [1.00, 2.37], P = .01, compared to good health status) were significant predictors of glaucoma diagnosis. For glaucomatous vision loss, having an income below the poverty threshold (OR = 2.41, 99% CI = [1.12, 5.20], P = .003, compared to income ≥5 times the poverty threshold) was the only significant predictor in univariable analyses. No SDH-related factors were significantly associated with glaucomatous vision loss in multivariable analysis (n = 848). Multicollinearity was minimal (variation inflation factor<1.6 for all independent variables).

CONCLUSIONS

Non-Hispanic Black race and poor health status were associated with self-reported glaucoma diagnosis. Physicians and policymakers may consider SDH when assessing clinical risk and designing public health interventions.

Comparison of disease severity in glaucoma patients identified by screening in the 1990s and in routine clinical care in the 2010s in Sweden

BACKGROUND AND PURPOSE

In a previous study comparing the amount of visual field damage at presentation in patients having open-angle glaucoma (OAG) identified through screening and in patients diagnosed in routine clinical practice in the 1990s, the damage was considerably worse in the clinically diagnosed patients. In the present study we compare visual field damage at presentation in the same 402 screened patients with that seen in 281 newly detected previously untreated patients clinically diagnosed in the 2010s.

METHODS

The perimetric visual field index mean deviation (MD) was compared in the two groups of patients.

RESULTS

In the clinical patients diagnosed with bilateral visual field damage the median MD was -5.1 dB in the better eye and -13.0 dB in the worse eye. In the screened patients the median MD in the better eye was -6.5 dB and -11.5 dB in the worse eye. The differences between the clinical and screened patients were non-significant, p = 0.28 and p = 0.67 respectively. More clinical patients had severe visual field loss, defined as MD less than -20 dB, in the worse eye than in the screened patients, 18.5% versus 12.7% respectively, p = 0.037.

CONCLUSION

The visual field damage at presentation in clinically diagnosed OAG patients has improved in the past 20 years, but the proportion of patients with severe visual field loss in at least one eye, almost 20%, is still unacceptably high considering that severe visual field damage at presentation is the most important risk factor for later development of glaucoma blindness.

Development and Validation of an Internet-Based Remote Perimeter (Perimouse)

Purpose

We sought to validate the feasibility of Perimouse, an internet-based remote perimeter that allows for natural fixation and can be performed on most computers via a web page.

Methods

In this cross-sectional study, Perimouse evaluated the visual field of 45 healthy people and 27 patients with primary open-angle glaucoma on a laptop. Participants used a mouse cursor to locate new dots on the screen that were determined by preset saccade vectors. A "click and confirm" strategy was used to eliminate the unwanted visual search. Dot brightness was either fixed at 12 dB in the suprathreshold program (screening program) or variable in the threshold program. We compared Perimouse outcomes with the Humphrey Field Analyzer (HFA) 24-2 Swedish Interactive Testing Algorithm standard program.

Results

In the screening program, Perimouse showed moderate to high concordance with HFA. The intraclass coefficient ranged from 0.58 to 0.86 in different areas of Garway-Heath mapping. In the threshold program, normal subjects had threshold ranging from 19 to 16 dB, presenting sensitivity changes according to the "hill of vision". The test-retest difference was 0.09 dB. Habitual spectacle correction and environmental luminance (2-337 lux) had little impact on the central or peripheral threshold (P > 0.05). The correlation between Perimouse and HFA threshold sensitivity was strong (R = 0.950), although Perimouse mean defect was 4.40 dB higher than the HFA mean defect.

Conclusions

Perimouse is a reliable visual field test that correlates strongly with HFA. It shows potential for population screening and monitoring visual field defects.

Translational Relevance

Perimouse assesses the visual field using saccade vectors without eye trackers, enhancing its accessibility via a web page.

Decreased macular deep capillary plexus is associated with functional progression of normal tension glaucoma patients with unilateral visual field loss

PURPOSE

To investigate whether quantitative optical coherence tomography angiography (OCTA) metrics of the superficial/deep macular retina are associated with the development of visual field (VF) loss in the fellow eyes of normal tension glaucoma (NTG) patients with unilateral VF loss.

METHODS

A longitudinal study was conducted in which 61 eyes with normal VF (mean VF mean deviation -0.7±1.6 dB) from 61 NTG patients were included. All subjects underwent OCTA imaging, spectral-domain-OCT imaging and VF testing. OCTA metrics of superficial capillary plexus and deep capillary plexus (DCP) in the macular region were measured. Relationships between baseline OCTA metrics, demographics and ocular characteristics and the risk of VF glaucoma progression were analysed with a Cox proportional hazards model.

RESULTS

During a mean follow-up of 38 months, 11 fellow eyes (18.0%) with normal VF at baseline were determined to have VF progression, while 21.3% of affected eyes had VF progression. After adjustment for potential confounding factors, decreased baseline DCP in the fellow eyes was significantly associated with future VF progression (HR 1.33, 95% CI 1.03 to 1.73, p=0.031).

CONCLUSION

Decreased DCP was associated with a higher risk of developing VF damage in NTG patients with unilateral VF loss. Assessments of DCP may help improve the evaluation of the risk of functional deterioration in fellow eyes with an initially normal VF.

Quality assessment of non-mydriatic fundus photographs for glaucoma screening in primary healthcare centres: a real-world study

BACKGROUND

This study assessed the quality distribution of non-mydriatic fundus photographs (NMFPs) in real-world glaucoma screening and analysed its influencing factors.

METHODS

This cross-sectional study was conducted in primary healthcare centres in the Yinzhou District, China, from 17 March to 3 December 2021. The quality distribution of bilateral NMFPs was assessed by the Digital Reading Department of the Eye Hospital of Wenzhou Medical University. Generalised estimating equations and logistic regression models identified factors affecting image quality.

RESULTS

A total of 17 232 photographs of 8616 subjects were assessed. Of these, 11.9% of images were reliable for the right eyes, while only 4.6% were reliable for the left eyes; 93.6% of images were readable in the right eyes, while 90.3% were readable in the left eyes. In adjusted models, older age was associated with decreased odds of image readability (adjusted OR (aOR)=1.07, 95% CI 1.06~1.08, p<0.001). A larger absolute value of spherical equivalent significantly decreased the odds of image readability (all p<0.001). Media opacity and worse visual acuity had a significantly lower likelihood of achieving readable NMFPs (aOR=1.52, 95% CI 1.31~1.75; aOR=1.70, 95% CI 1.42~2.02, respectively, all p<0.001). Astigmatism axes within 31°~60° and 121°~150° had lower odds of image readability (aOR=1.35, 95% CI 1.11~1.63, p<0.01) than astigmatism axes within 180°±30°.

CONCLUSIONS

The image readability of NMFPs in large-scale glaucoma screening for individuals 50 years and older is comparable with relevant studies, but image reliability is unsatisfactory. Addressing the associated factors may be vital when implementing ophthalmological telemedicine in underserviced areas.

TRIAL REGISTRATION NUMBER

ChiCTR2200059277.

Impact of primary glaucoma on health-related quality of life in China: the handan eye study

BACKGROUND

We assessed health-related quality of life (HRQOL) and its determinants among rural glaucoma participants compared to age-matched normal controls in the population-based Handan Eye Study (HES), in rural Yongnian County, northern China.

METHODS

We enrolled 99 adults with glaucoma (mean age 63.0 ± 11.0 years), including primary open-angle glaucoma (POAG, n = 67) and primary angle-closure glaucoma (PACG, n = 32) and 102 controls (mean age 58.5 ± 5.3 years) with normal visual acuity and visual field and no history of glaucoma. Results of ophthalmic examinations and socioeconomic data were recorded. HRQOL was measured using the EQ-5D (converted to utility valves, UVs), and visual function (VF) and vision-related quality of life (VRQOL) were evaluated using the visual function-quality of life (VF-QOL) instrument.

PRIMARY AND SECONDARY OUTCOME MEASURES

EQ-5D and VF-QOL scores.

RESULTS

The mean UVs, VF, and VRQOL scores for glaucoma cases were 0.98 ± 0.04, 87.9 ± 15.2, and 95.5 ± 12.8, respectively, significantly worse than VF (94.4 ± 4.4) and VRQOL (100.0 ± 0.0) among controls, even after adjusting for age, gender, educational level, and family income (P = 0.015, P = 0.033). UVs were significantly lower among glaucoma participants with impaired VRQOL (55.4 ± 11.5) compared to those with normal VRQOL scores (99.1 ± 2.8) (UVs: 0.92 ± 0.08 vs. 0.99 ± 0.03, P = 0.036), also after adjustment for age and family income (P = 0.006). Participants with PACG had significantly lower VF and VRQOL scores compared to POAG (77.8 ± 21.4 vs. 92.9 ± 6.8, P < 0.001; 89.0 ± 18.1 vs. 98.7 ± 7.5, P < 0.001).

CONCLUSION

Participants with glaucoma have worse visual function and related quality of life compared to age-matched normal population controls. Participants with PACG have lower VF and VRQOL compared to those with POAG. UVs can be used for cost-effectiveness research and to support public health strategies for glaucoma in rural China.

Progressive Macular Vessel Density Loss Observed on Optical Coherence Tomography Angiography in Glaucoma Patients With Single-Hemifield Visual Field Defects

PRCIS

Faster hemispheric mVD loss was found in the affected hemifield of POAG patients without significant changes in hemispheric thickness. The progression of mVD loss was associated with the severity of VF damage.

PURPOSE

To evaluate the changes in macular vessel density (mVD) loss in primary open angle glaucoma (POAG) patients with visual field (VF) defects confined to 1 hemifield.

MATERIALS AND METHODS

This longitudinal cohort study used linear mixed models to evaluate the changes in the hemispheric mean total deviation (mTD), mVD, macular ganglion cell complex, macular ganglion cell-inner plexiform layer, and retinal nerve fiber layer between affected hemifields, unaffected hemifields, and healthy controls.

RESULTS

Twenty-nine POAG eyes and 25 healthy eyes were followed for an average of 29 months. In POAG eyes, the rates of decline in hemispheric mTD and hemispheric mVD in the affected hemifields were significantly faster than those in the unaffected hemifields (-0.42±1.24 vs. 0.02±0.69 dB/year, P =0.018 and -2.16±1.01 vs. -1.77±0.90% / year, P =0.031, respectively). There were no differences in the rate of hemispheric thickness change between the 2 hemifields. The rate of hemispheric mVD decline in both hemifields of POAG eyes was significantly faster than that of the healthy controls (All P <0.05). An association between the reduced mTD of the VF and the rate of hemispheric mVD loss in the affected hemifield was observed (r=0.484, P =0.008). Faster rates of mVD loss (β=-1.72±0.80, P =0.050) were significantly related to reduced hemispheric mTD in the multivariate analysis.

CONCLUSIONS

Faster hemispheric mVD loss was found in the affected hemifield of POAG patients without significant changes in hemispheric thickness. The progression of mVD loss was associated with the severity of VF damage.

The Patterns of Visual Field Defects in Primary Angle-Closure Glaucoma Compared to High-Tension Glaucoma and Normal-Tension Glaucoma

INTRODUCTION

The aim of this study was to compare the patterns of visual field (VF) defects in primary angle-closure glaucoma (PACG) to control groups of eyes with high-tension glaucoma (HTG) and normal-tension glaucoma (NTG).

METHODS

Forty-eight eyes with PACG were enrolled, and control eyes with HTG and NTG matched for age, sex, and mean deviation of VF defect were selected. VF tests were performed using the 24-2 program of the Humphrey field analyzer. VF defects were classified into six patterns with the Ocular Hypertension Treatment Study classification system and were categorized into three stages (early, moderate, and advanced). Each hemifield was divided into five regions according to the Glaucoma Hemifield Test (GHT). The mean total deviation (TD) of each GHT region was calculated.

RESULTS

Compared with HTG and NTG groups, the partial arcuate VF defects were more common in the PACG group. In the PACG group, the nasal GHT region in the inferior hemifield had the worst mean TD (-8.48 ± 8.62 dB), followed by the arcuate 1 (-7.81 ± 7.91 dB), arcuate 2 (-7.46 ± 7.43 dB), paracentral (-7.19 ± 7.98 dB), and central (-5.14 ± 6.24 dB) regions; the mean TD of the central region was significantly better than those for all other regions (all p < 0.05). A similar trend was observed in the superior hemifield in the PACG group but not the VF hemifields of the HTG and NTG groups.

CONCLUSION

Patterns of VF defect in PACG patients differ from those with HTG and NTG. This discrepancy might be due to the differences in the pathogenic mechanisms of glaucomatous optic neuropathy.

Performance of a Glaucoma Screening Program Compared With Opportunistic Detection in China

PRCIS

Health examination center-based screening provide a good supplement to clinic-based glaucoma care by detecting early-stage glaucoma, especially those with normal intraocular pressure (IOP) and less visual impairment.

PURPOSE

Opportunistic glaucoma screening for early case identification is of great value in the prevention of severe visual impairment, however, novel, low-cost models are needed. We aimed to determine whether health examination center-based glaucoma screening identifies diseases earlier than outpatient cases in China.

MATERIALS AND METHODS

In this case-control study, 76 patients with primary glaucoma identified from a health examination center-based glaucoma screening program and 272 consecutive outpatient cases at the same hospital were enrolled from March 21 to September 30, 2016. Demographic characteristics, best-corrected visual acuity, IOP, mean deviation (MD), and pattern standard deviation (PSD) on Humphrey visual field testing in the better-seeing eye were compared between groups.

RESULTS

Screening-detected glaucoma patients had significantly lower IOP (18.3±4.2 mm Hg) than out-patient cases (26.7±12.6 mm Hg, P <0.001). Most (71.1%) of the screening-detected patients had IOP<21 mm Hg compared with 37.1% in the clinic group ( P <0.001). Seventy-five patients (98.7%) in the screening group were diagnosed as primary open angle glaucoma, compared with 44.1% in the clinic group ( P <0.001). Screening-detected patients had significantly less visual impairment than the clinic group (6.6% vs. 38.6%, P <0.05). Mean MD (-4.4±5.0 dB) and PSD (4.4±3.6 dB) for the screening group were superior to the clinic group (MD: -16.5±10.5 dB, P <0.001; PSD: 6.5±3.7 dB, P <0.001).

CONCLUSION

The glaucoma screening program was effective at detecting early disease, especially normal tension glaucoma and supplemented opportunistic detection of glaucoma.

Research progress of exosomes in pathogenesis, diagnosis, and treatment of ocular diseases

Exosomes are natural extracellular vesicles with a diameter of 30-150 nm, which exist in biological fluids and contain biomolecules related to the parent cell, such as proteins, nucleic acids, lipids, etc. It has a wide range of biological functions, and participates in the regulation of important physiological and pathological activities of the body. It can be used as a biomarker for early diagnosis of ocular diseases, a potential therapeutic target, a targeted drug carrier, and has a high potential for clinical application. In this paper, we summarized the genesis mechanism, biological functions, research and application progress of exosomes, focused on the engineering strategy of exosomes, and summarized the advantages and disadvantages of common engineering exosome preparation methods. Systematically combed the role of exosomes in corneal diseases, glaucoma, and retinal diseases, to provide a reference for further understanding of the role of exosomes in the pathogenesis, diagnosis, and treatment of ocular diseases. Finally, we further summarized the opportunities and challenges of exosomes for precision medicine. The extension of exosome research to the field of ophthalmology will help advance current diagnostic and therapeutic methods. Tiny exosomes have huge potential.

Population-based associations between progression of normal-tension glaucoma and Yang-deficient constitution among Chinese persons

PURPOSE

To explore the association between constitution types as defined by traditional Chinese medicine (TCM) and risk for normal-tension glaucoma (NTG).

DESIGN

Population-based cohort study.

METHODS

Persons were identified in a population cohort aged ≥30 years with NTG, defined as having an untreated mean intraocular pressure measurement ≤21 mm Hg over six separate occasions, with no single reading >24 mm Hg (as in the Collaborative Normal Tension Glaucoma Study). The Body Constitution in Traditional Chinese Medicine Questionnaire was used to assess each participant's TCM constitution types. The association between various constitutions and visual field progression according to Early Manifest Glaucoma Trial criteria was assessed using Cox regression HR models.

RESULTS

Among 142 participants (245 eyes), 23 persons (17.6%) and 25 eyes (10.2%) progressed, over a mean (SD) follow-up duration of 3.49 (0.99) years. Progression rates were highest in participants with Yang-deficient constitution (n=19, 13.4%), among whom 7 (36.8%) exhibited worsening fields. After adjusting for sex, age, central corneal thickness, retinal nerve fibre layer thickness and mean deviation on visual field testing, Yang-deficient constitution (HR 4.63, 95% CI 1.77 to 12.1, p=0.002) and higher mean intraocular pressure during follow-up (HR 1.25, 95% CI 1.01 to 1.56, p=0.044) were associated with field progression.

CONCLUSIONS

Yang-deficient constitution and higher intraocular pressure are risk factors for visual field progression in NTG patients. Yang deficiency is characterised by abnormal vasoregulation, and these results may be consistent with prior studies linking NTG progression to Raynaud's phenomenon and migraine.

Effectiveness of community outreach screening for glaucoma in improving equity and access to eye care in Nigeria

PURPOSE

To determine the effectiveness of community outreach screening for glaucoma in improving equity and access to eye care in Nigeria.

METHODOLOGY

This was a prospective study in which two cohort of participants were recruited in Nigeria: 1 from 24 outreach screenings and another from consecutive patients presenting spontaneously to a tertiary eye clinic in Nigeria. Sociodemographic and clinical data were obtained from participants and compared.

RESULTS

Our sample consisted of 120 patients with glaucoma or suspected glaucoma (6.38% of 1881 screenees) recruited from the 24 outreach screenings, and another 123 patients with glaucoma who presented spontaneously at the eye clinic. Participants from the screenings were significantly older (p=0.012), less educated (p<0.001), had lower incomes (p<0.001), lower glaucoma knowledge scores and were less aware of their glaucoma (both p<0.001) and were more likely to be dependent on relations and children (p=0.002) compared with clinic participants. Of the 120 patients identified at the screenings and referred to the clinic for definitive care, 39 (32.5%) presented at the clinic within 3 months. Reasons for poor uptake of referral services were lack of a felt need and lack of money for transportation. Considering only patients who accepted referral, they were still less educated (p<0.001), poorer (p=0.001) and less knowledgeable about glaucoma (p=0.003) than spontaneous clinic presenters.

CONCLUSION

Outreach screening improved equity of access but its effects were somewhat reduced by poor uptake of referral care. Interventions such as free transportation and educational efforts may improve the uptake of referral services and maximise equity gains.

Disease Burden of Glaucoma in China: Findings from the Global Burden of Disease 2019 Study

Purpose

To provide evidence for future strategies in preventing glaucomatous blindness by investigating the disease burden in terms of age, year, and gender from 1990 to 2019 in China.

Methods

The prevalence and disability-adjusted life years (DALYs) of blindness and vision loss due to glaucoma in China were extracted from the Global Burden of Disease (GBD) 2019 study. Age-standardized data is presented in comparison to China’s neighboring countries.

Results

From 1990 to 2019, the prevalent cases and DALYs number with glaucomatous blindness and vision loss increased by 129.53% and 67.29%, respectively. Overall, higher age-standardized prevalence and DALYs rate were detected in males than in females between 1990 and 2019, and people aged 60 to 89 years suffered from a higher DALY number than other age groups in 2019. Among the neighboring countries, China ranked from fourth in 1990 (88.52, 95% uncertainty interval [UI]: 74.62 to 103.24, per 100,000 population) to third in 2019 (71.14, 95% UI: 59.34 to 84.42, per 100,000 population) in age-standardized prevalence while from fourth in 1990 (10.13, 95% UI: 6.68 to 14.46, per 100,000 population) to sixth in 2019 (5.98, 95% UI: 4.14 to 8.42, per 100,000 population) in age-standardized DALYs. Compared with other GBD regions, the largest decrease in age-standardized DALY rate due to glaucoma was found in China (−40.87%, 95% UI: −43.97% to −37.82%). A higher percentage decrease in age-standardized prevalence was also found in China (−19.66%, 95% UI: −22.44% to −17.09%).

Conclusion

Substantial increases in the prevalence of visual impairment and DALYs number of glaucoma were observed from 1990 to 2019. Efforts targeting glaucoma prevention and treatment in China are urgently required, especially for the elderly population and men.

Eye diseases burden in China in the past 30 years

To investigate the national burden of eye diseases in China from 1990 to 2019. The national burden of eye diseases in China, including case numbers, prevalence rate, age-standardized prevalence rate (ASR), disability-adjusted life year (DALY), DALY rate and age-standardized DALY rate (ASD) were calculated and stratified by sex and age. The trends of eye diseases burden from 1990 to 2019 and the correlation between eye diseases burden and human development index (HDI) were analyzed. In 2019, the total case number of eye diseases in China was 0.21 billion, the ASR was 9511/10, the total number of DALY was 4.72 million, and the ASD was 247.4/10. Near vision loss caused the greatest burden, followed by refraction disorders and cataract, with ASD being 73.8/10, 70.3/10 and 59.2/10, respectively. Men had lower risks of eye diseases than women. People aged old and old had the greatest burden of eye diseases. Compared with the year 1990, the total case number increased by 134.6% and DALY by 113.0% in 2019. The ASD of all decreased by 7.5%, and was negatively correlated with national HDI. Near vision loss, refraction disorders and cataract are of heavy disease burden in China. Although the ASD of eye diseases is decreased with the development of the national socioeconomic status, the eye diseases burden in China still increased with population growth and aging.

Intraocular asymmetry of visual field defects in primary angle-closure glaucoma, high-tension glaucoma, and normal-tension glaucoma in a Chinese population

Direct comparison data on spatial patterns of visual field (VF) defects among primary angle-closure glaucoma (PACG), high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) are not available. We aimed to compare the intraocular asymmetry of VF loss among patients with PACG, NTG and HTG across different severity levels. A total of 162 eyes of 114 patients with PACG, 111 eyes of 74 patients with HTG and 148 eyes of 102 patients with NTG were included. VF defects were categorized into 3 stages (early, moderate, and advanced), and each hemifield was divided into 5 regions according to the Glaucoma hemifield test (GHT). The mean total deviation (TD) of each GHT region was calculated. In the early stage, the paracentral, peripheral arcuate 1 and peripheral arcuate 2 regions in the superior hemifield in the NTG group had significantly worse mean TDs than their corresponding regions in the inferior hemifield. In the advanced stage, the central region in the superior hemifield in the PACG group had a significantly worse mean TD than that in the inferior hemifield. There was no significant difference in the mean TD for any of the five regions between hemifields across all severity levels in the in the HTG group. The superior hemifield was affected more severely than the inferior hemifield in all three subtypes of primary glaucoma. This asymmetric tendency was more pronounced in NTG than in PACG and HTG.

Visual disability among patients attending glaucoma clinic in a tertiary hospital

PURPOSE

To report visual impairment and blindness among the patients attending a glaucoma clinic in a tertiary university hospital and highlight the possible risk factors that could be addressed later.

METHODS

A retrospective analysis of the medical records of the patients attending the glaucoma clinic in Ain Shams University Hospitals over a period of one year was conducted. Visual impairment classification was done according to the International Classification of Diseases and Related Health Problems (ICD-11) based on the best-corrected visual acuity in the better-seeing eye. Data including diagnosis, history of previous surgery, and duration of glaucoma were extracted and analyzed.

RESULTS

The medical records of the first visit of 118 patients (58 males and 60 females) were included in this study. Secondary glaucoma was the most common type presented (38 patients, 32.2%), followed by primary open-angle glaucoma (35 patients, 29.6%). Sixty-seven patients (56.7%) were considered visually impaired, while seven patients (5.9%) were considered blind. Forty-one patients (34.7%) were considered mono-ocular blind.

CONCLUSION

There is a high incidence of visual impairment and blindness among glaucoma patients presented to the glaucoma clinic in the  tertiary hospital. A further nation-wide study and possibly, an early surveillance program for glaucoma are needed.

Interocular Asymmetry of Visual Field Loss, Intraocular Pressure and Corneal Parameters in Primary Open-angle Glaucoma

OBJECTIVES

To assess the association between the corneal biomechanical parameters and visual field (VF) loss in patients with asymmetric primary open-angle glaucoma (POAG).

METHODS

A total of 89 POAG patients (50 males, 56.2%) with asymmetric VF loss, aged 65.2 ± 13.3 years old, were enrolled in this study. Asymmetric VF loss was defined as an interocular difference of the global index mean deviation (MD) >2dB. Intraocular pressure (IOP), central corneal thickness (CCT) and corneal biomechanical parameters such as maximum amplitude at the apex of highest concavity (Def ampl HC) were measured. The worse eye was defined as the eye with a smaller MD.

RESULTS

The worse eyes had lower MD (-11.9 ± 6.7 dB vs. -5.3 ± 5.0 dB; P<0.001) and higher IOP (14.6 ± 3.3 vs.13.9 ± 2.6 mmHg, P=0.04) than the better eyes. There was no significant difference between the two groups for CCT. The interocular difference of MD (IDMD) was negatively correlated with the interocular difference of IOP (r=-0.22, P=0.04), while positively correlated with the interocular difference of Def ampl HC (r=0.27, P=0.01). In patients with moderate asymmetric VF loss (IDMD ≥6 dB), the Def ampl HC of the worse eyes group (1.07 ± 0.12 mm) were significantly lower than the better eyes group (1.10 ± 0.11 mm, p=0.02).

CONCLUSION

Asymmetric POAG was associated with asymmetry in IOP and corneal biomechanical parameters but not in CCT. Lower deflection amplitude and higher IOP was found in eyes with more severe visual field damage in POAG patients.

Effect of a complex intervention to improve post-vision screening referral compliance among pre-school children in China: A cluster randomized clinical trial

BACKGROUND

We investigated whether specific appointments for quality-assured care could increase referral uptake, often low in China, in children's vision screening.

METHODS

We randomized children aged 4-7 years in Yudu, Jiangxi, China, by school to Control (free school-based eye screening, parents of children failing screening recommended for further examination [usual practice]) or Intervention (identical examinations, with parents additionally provided with specific appointments for further examinations by quality-assured doctors at a designated local hospital). Both groups could select any hospital for referral exams, which were not free. Six months after screening, parents were interviewed on referral compliance at any hospital (primary outcome) and potential determinants. This trial is registered at the ClinicalTrials.gov, number NCT03251456.

FINDINGS

Among 9936 children at 63 schools randomized to Intervention (32 schools, 5053 [50·9%] children) or Control (31 schools, 4883 [49·1%] children), 1114 children (11·2%) failed screening. Among 513 referred Intervention children (46·1%, 32 schools, mean age 5·36 years, 53·0% boys) and 601 referred Control children (53·9%, 31 schools, mean age 5·30 years, 57·7% boys), 104 (20·3%) and 135 (22·5%) were lost to follow-up respectively. Under Intention to Treat analysis, assuming children lost to follow-up were non-compliant, Intervention children had significantly higher compliance than Controls (308/513 = 60·0% vs. 225/601 = 37·4%, P < 0·001). In regression models, Intervention group membership (Relative risk [RR] 1·53, 95% confidence interval, 1·36-1·72), travel time to hospital (RR: 0·97, 0·95-0·999), baseline glasses wear (RR: 1·37, 1·17-1·60), strabismus (RR: 1·17, 1·01-1·36) and worse uncorrected vision (RR: 1·41, 1·03-1·92) were associated with compliance.

INTERPRETATION

Providing specific appointments for quality-assured eye care improved referral compliance in this setting.

Design and baseline data of a population-based metabonomics study of eye diseases in eastern China: the Yueqing Ocular Diseases Investigation

Background

China is undergoing a massive transition toward an urban and industrial economy. These changes will restructure the demographics and economy which will eventually influence the future patterns of disease. The risk factors of vision-impairing eye diseases remain ambiguous and poorly understood. Metabolomics is an ideal tool to understand and shed light on the ocular disease mechanisms for earlier treatment. This article aims to describe the design, methodology and baseline data of the Yueqing Ocular Diseases Investigation (YODI), a developed county population-based study to determine the prevalence and primary causes of visual impairment; also with metabonomics analysis we aimed to identify, predict and suggest some preventive biomarkers that cause blindness.

Methods

A population-based, cross-sectional study. Randomized clustering sampling was used to identify adults aged 50 years and older in Xiangyang Town, Yueqing county-level City. The interviews covered demographic, behavioral, ocular risk factors and mental health state. The ocular examination included visual acuity, autorefraction, intraocular pressure, anterior and posterior segment examinations, fundus photography, retinal tomography and angiography, and visual field testing. Anthropometric measurements included height and weight, waist and hip circumference, blood pressure, pulse rate, electrocardiogram, and abdominal ultrasound scan. A venous blood sample was collected for laboratory tests and metabonomics studies.

Results

Of the 5319 individuals recruited for the YODI, 4769 (89.7%) subjects were enrolled for analyses. The median age was 62.0 years, and 45.6% were male. The educational level of illiteracy or semi-illiteracy, primary, middle and high school or above was 29.8%, 45.5%, 20.1%, and 3.3%, respectively. Majority of the participants were female, younger, and less educated when compared with nonparticipants. The average body mass index and waist-hip ratios were 24.4 ± 3.4 kg/m² and 0.9 ± 0.1 respectively. Blood sample collection reached a sample size of 1909 (479 from subjects with self-reported diabetes and 1430 from one-third of the 4290 subjects without self-reported diabetes).

Conclusions

The YODI provides population-based data with a high response rate (89.7%) on the prevalence and primary causes of major vision-impairing eye diseases in developed county areas in eastern China. Metabonomics analysis from YODI will provide further association of metabolic characteristics with the visual impairment eye diseases. The risk prediction model could be created and has the potential to be generalized to developed eastern areas in China for prevention.

Parapapillary Choroidal Microvasculature Dropout Is Associated With the Decrease in Retinal Nerve Fiber Layer Thickness: A Prospective Study

Purpose

To explore the correlation between longitudinal changes of peripapillary retinal nerve fiber layer (RNFL) thickness and the presence of parapapillary choroidal microvasculature dropout (MvD).

Methods

This is a longitudinal cohort study. All patients with normal-tension glaucoma (NTG) were recruited from the Wenzhou Glaucoma Progression Study. The presence of MvD was determined using optical coherence tomography (OCT) angiography and the RNFL thickness was evaluated by spectral-domain OCT. All assessments were performed both at baseline and at every 3-month follow-up for at least 18 months.

Results

Seventy-one eyes were included. The presence of MvD was observed in 23 NTG eyes (32.4%). Eyes with MvD had a thinner RNFL (68.8 ± 9.6 vs. 76.2 ± 16.7 μm, P = 0.016) and a faster rate of RNFL loss (-1.2 ± 1.5 vs. -0.4 ± 1.4 μm/y, P = 0.036) compared with those without MvD. In a univariate analysis of rates of RNFL loss, the presence of MvD at baseline (β = -0.83 ± 0.38, P = 0.033) was significantly associated with progressive RNFL loss. After adjusting for age, female sex, mean follow-up IOP, axial length, central corneal thickness, and mean deviation, the presence of MvD at baseline (β = -0.85 ± 0.41, P = 0.041) was significantly associated with faster rates of RNFL loss in the multivariate analysis.

Conclusions

There is a significant correlation between the presence of MvD and decrease in RNFL thickness in NTG patients. Our study further supported that the presence of MvD is a predictor of longitudinal RNFL damage in glaucoma.

Cost-effectiveness and cost-utility of population-based glaucoma screening in China: a decision-analytic Markov model

BACKGROUND

Glaucoma, particularly primary angle closure glaucoma (PACG), is a leading cause of global blindness. Nearly half of all people with PACG are of Chinese descent. Population-level glaucoma screening has generally not been found to be cost-effective in high-income countries; however, this assessment has rarely been done in low-income or middle-income countries. We aimed to assess the cost-effectiveness and cost-utility of population-level glaucoma screening in China.

METHODS

We developed decision-analytic Markov models for separate and combined screening for PACG and primary open angle glaucoma (POAG) to evaluate costs and benefits of community-level screening versus opportunistic case finding from a societal perspective. A cohort of individuals was followed in the model from age 50 years through a total of 30 1-year Markov cycles. Analyses were done separately for rural and urban settings. We did a meta-analysis of glaucoma prevalence studies in China to obtain prevalence estimates for PACG and POAG. Screening costs were taken from a Chinese screening programme and treatment costs from a tertiary Chinese eye hospital. Main outcomes were incremental cost-utility ratios (ICURs) using quality-adjusted life-years and incremental cost-effectiveness ratios (ICERs) using years of blindness avoided. We did one-way deterministic and simulated probabilistic sensitivity analyses to reflect uncertainty around ICURs and ICERs.

FINDINGS

Compared with no screening, combined screening of POAG and PACG in rural China is predicted to result in an ICUR of US$569 (95% CI 17 to 4180) and an ICER of $1280 (-58 to 7940), both of which are below the WHO cost-effectiveness threshold of one to three times rural gross domestic product. For the urban China setting, combined screening is predicted to result in fewer net costs and greater gain in health benefits than no screening. Findings were robust in all sensitivity analyses. Over 30 years, a total of 246 (95% CI 63 to 628) and 1325 (510 to 2828) years of blindness are predicted to be avoided for every 100 000 rural and urban residents screened, respectively.

INTERPRETATION

Population screening for glaucoma (POAG and PACG combined) is likely to be cost-effective in both urban and rural China. Future studies should investigate the effectiveness of interventions to improve acceptance of definitive care among people screened.

FUNDING

Ulverscroft Foundation, Wenzhou Medical University Research Fund, Zhejiang Province Health Innovation Talents Project, and Wenzhou's Ten Major Livelihood Issues 2015.