Prevalence of uncorrected refractive errors, presbyopia and spectacle coverage in marine fishing communities in South India: Rapid Assessment of Visual Impairment (RAVI) project

Cross-sectional study of prevalence, causes and trends in visual impairment in Nirmal District, Telangana, India: Nirmal Eye Evaluation for Trends study

OBJECTIVE

To determine the prevalence, causes and risk factors associated with visual impairment (VI) in the Nirmal district of Telangana, India, using extended Rapid Assessment of Visual Impairment (RAVI) methodology.

DESIGN

Cross-sectional study.

SETTING

Community setting.

PARTICIPANTS

Participants aged ≥16 years were enumerated from 90 randomly selected clusters and 4629/5400 (85.7%) participants were examined. Presenting visual acuity (VA) was assessed using a Snellen chart with E optotypes at a 6 m distance. Near vision was assessed binocularly using an N notation chart with tumbling E optotypes at a 40 cm distance. An anterior segment examination done followed by distance direct ophthalmoscopy at 50 cm. Non-mydriatic fundus images were obtained. VI was defined as presenting VA worse than 6/12 in the better eye. The prevalence of VI in the current study was compared with a RAVI study conducted in 2014 to assess the trends in VI among those aged ≥40 years.

PRIMARY OUTCOME

Prevalence, causes and risk factors for VI.

RESULTS

Among those examined, 55% were women, 53% had at least school-level education, 2.3% self-reported diabetes and 8.7% self-reported hypertension. The prevalence of VI was 8.81% (95% CI 8.01% to 9.67%). Overall, uncorrected refractive errors (49.5%) were the leading cause of VI, followed by cataracts (40.2%) and posterior segment diseases (4.9%). Among those aged ≥40 years, the prevalence of VI declined by 19.3% compared with the 2014 baseline study (from 20.2% to 16.3%; p<0.01).

CONCLUSION

The extended RAVI study conducted in the Nirmal district showed a considerable decline in the prevalence of VI. Targeted interventions are needed to provide adequate eye care for the high-risk groups in this district.

Near vision impairment and effective refractive error coverage for near vision in Andhra Pradesh, India - The Akividu Visual Impairment Study (AVIS)

CLINICAL RELEVANCE

Near Vision Impairment (NVI) is common in developing countries. A substantial proportion of NVI can be addressed by providing spectacles. Innovative eye care programmes are needed to address NVI. Population-based epidemiological studies can provide vital data to plan such eye care service delivery models.

BACKGROUND

To report the prevalence of NVI and effective Refractive Error Coverage (eREC) for near vision in West Godavari and Krishna districts in Andhra Pradesh, south India.

METHODS

A population-based cross-sectional study was carried out using a Rapid Assessment of Visual Impairment methodology. Presenting and pinhole distance visual acuity were assessed followed by near vision assessment using a N notation chart at a fixed distance of 40 cm. If the presenting near vision was worse than N8, the best corrected near visual acuity was recorded with age appropriate near vision correction. NVI was defined as presenting near vision worse than N8 among those without distance vision impairment (6/18 or better in the better eye). Effective Refractive Error Coverage for near was calculated as the proportion of individuals with an adequate correction to the total participants, including those with inadequate, adequate, and no correction for near vision.

RESULTS

Data of 2,228 participants aged ≥40 years were analysed. The mean age of these participants was 54.0 ± 10.4 years; 53.8% were women; 44.5% had no formal education. The prevalence of NVI was 27.1% (95% CI: 25.2-29.0%). NVI significantly associated with 70 and above age group (adjusted OR: 1.97; 95% CI: 1.45-3.70). Participants with formal education had lower odds for NVI (adjusted OR: 0.75; 95 % CI: 0.68-0.83). The eREC for near vision was 48.0%.

CONCLUSION

NVI affects over a quarter of people aged ≥40 years in the West Godavari and Krishna districts of Andhra Pradesh. However, eREC is under 50% and there is scope for improving this by establishing eye care services to achieve universal eye health for all.

BCLA CLEAR Presbyopia: Epidemiology and impact

The global all-ages prevalence of epidemiologically-measured 'functional' presbyopia was estimated at 24.9% in 2015, affecting 1.8 billion people. This prevalence was projected to stabilise at 24.1% in 2030 due to increasing myopia, but to affect more people (2.1 billion) due to population dynamics. Factors affecting the prevalence of presbyopia include age, geographic location, urban versus rural location, sex, and, to a lesser extent, socioeconomic status, literacy and education, health literacy and inequality. Risk factors for early onset of presbyopia included environmental factors, nutrition, near demands, refractive error, accommodative dysfunction, medications, certain health conditions and sleep. Presbyopia was found to impact on quality-of-life, in particular quality of vision, labour force participation, work productivity and financial burden, mental health, social wellbeing and physical health. Current understanding makes it clear that presbyopia is a very common age-related condition that has significant impacts on both patient-reported outcome measures and economics. However, there are complexities in defining presbyopia for epidemiological and impact studies. Standardisation of definitions will assist future synthesis, pattern analysis and sense-making between studies.

Prevalence of uncorrected distance refractive errors and associated risk factors in employees of an academic centre

BACKGROUND

Uncorrected refractive error (RE) may affect the work performance of adults in the workplace. The aim of current study was to determine the prevalence of corrected and uncorrected RE, and the determinants of uncorrected RE in adult employees of a university.

METHODS

This was a cross-sectional study of Tehran University Medical Sciences' staff. Besides demographic and some specific questionnaires, ophthalmic examinations including the measurement of uncorrected visual acuity (UCVA), best spectacles corrected visual acuity (BCVA), and presenting visual acuity were performed for all participants. The need for spectacles was defined as UCVA worse than 6/12 in the better eye that could be corrected to better than 6/12 with spectacles based on subjective refraction.

RESULTS

In total, 4460 individuals with mean age of 42.32 ± 8.80 were included in the study. The VA of the better eye was 0.01 ± 0.05 logMAR for BCVA, 0.13 ± 0.26 for UCVA, and 0.05 ± 0.12 for presenting VA. Prevalence of RE was 15.7%, including uncorrected RE of 5% and spectacles coverage (corrected RE) of 10.7%. The proportion of individuals with elementary education and poor-fair status of general health were 1.62 times higher in the uncorrected group. In the univariate analysis, type of occupation (office versus non-office workers), socioeconomic status, and insurance of employees were not related to uncorrected RE (all P > 0.4). Myopia was the only factor associated with uncorrected RE in logistic regression analysis (odds ratio = 2.73, 95%CI = 1.02-7.31, P = 0.04).

CONCLUSION

The prevalence of uncorrected RE and spectacle coverage were 5% and 10.7%, respectively. Myopia was almost three times more likely to be associated among employees with uncorrected RE.

Uncorrected refractive error in a university community

Aims and Background

To determine the prevalence and pattern of uncorrected refractive error among staff of a Nigerian university.

Patient and Methods

A cross-sectional study of consecutive staff of the University of Nigeria, Nsukka, Nigeria who presented for a 10-day free eye screening program. Demographic data and data on eye care awareness and knowledge were obtained with a combination of self-administered and interviewer-administered questionnaires in the English language. Clinical examinations included visual acuity taken at 6 m with Snellen's chart; noncontact tonometry; pen-torch eye examination; and direct ophthalmoscopy; autorefraction and subjective refraction.

Results

One thousand and eighty-three subjects aged 18-82 years (mean = 44.1 ± 12.15 years) comprising 568 females (52.4%) and 515 males (47.6%) were screened. Eighty-nine subjects (8.3%) were visually impaired and five subjects (0.5%) were blind. Three hundred and fifty-six subjects were diagnosed with refractive error (356/1083; 32.9%), out of which 149 subjects (41.9%) were uncorrected. The prevalence of uncorrected refractive error in this study population was 13.8%. Astigmatism was the commonest refractive error, whereas hypermetropia and hypermetropic astigmatism were the commonest spherical and astigmatic errors, respectively.

Conclusion

A significant proportion of the staff of this Nigerian university still lives with uncorrected refractive error with its attendant consequences. Regular eye checks should be done by the staff of our universities and effort should be intensified in eye care awareness creation among the populace, including the apparently enlightened communities.

Estimating need and coverage for five priority assistive products: a systematic review of global population-based research

INTRODUCTION

To improve access to assistive products (APs) globally, data must be available to inform evidence-based decision-making, policy development and evaluation, and market-shaping interventions.

METHODS

This systematic review was undertaken to identify studies presenting population-based estimates of need and coverage for five APs (hearing aids, limb prostheses, wheelchairs, glasses and personal digital assistants) grouped by four functional domains (hearing, mobility, vision and cognition).

RESULTS

Data including 656 AP access indicators were extracted from 207 studies, most of which (n=199, 96%) were cross-sectional, either collecting primary (n=167) or using secondary (n=32) data. There was considerable heterogeneity in assessment approaches used and how AP indicators were reported; over half (n=110) used a combination of clinical and self-reported assessment data. Of 35 studies reporting AP use out of all people with functional difficulty in the corresponding functional domains, the proportions ranged from 4.5% to 47.0% for hearing aids, from 0.9% to 17.6% for mobility devices, and from 0.1% to 86.6% for near and distance glasses. Studies reporting AP need indicators demonstrated >60% unmet need for each of the five APs in most settings.

CONCLUSION

Variation in definitions of indicators of AP access have likely led to overestimates/underestimates of need and coverage, particularly, where the relationship between functioning difficulty and the need for an AP is complex. This review demonstrates high unmet need for APs globally, due in part to disparate data across this sector, and emphasises the need to standardise AP data collection and reporting strategies to provide a comparable evidence base to improve access to APs.

Prevalence of presbyopia, spectacles coverage and barriers for unmet need among adult population of rural Jhajjar, Haryana

Background:

Presbyopia is a major cause for near visual impairment among adults. Presbyopia induced visual impairment can be corrected easily by spectacles. We aimed to study the prevalence of presbyopia among adults aged ≥35 years and spectacles coverage among them. We also studied the unmet need for presbyopia along with the barriers to uptake of services.

Methods:

This is a population-based cross-sectional study conducted among adults aged ≥35 years in a rural district of Haryana. Near vision assessment and semistructured interview schedule were administered by a team of trained ophthalmic assistant, social worker and health assistant.

Results:

A total of 3832 adults aged ≥35 years were enumerated, from which 3246 (84.7%) were examined. Prevalence of presbyopia was found to be 42.9% (95% confidence interval 41.2–44.6). Participants with increasing age, literacy and women had higher prevalence, and those that were employed and belonged to below poverty line economic status had lower prevalence of presbyopia. Spectacles coverage among presbyopes was found to be 25.8%. There was an inverse association between unmet need for presbyopia and women, increasing education status and office work. Lack of felt need and personal reasons were the most common barriers for unmet need due to presbyopia.

Conclusions:

There is high prevalence of presbyopia among adult population, with spectacles coverage being low. Awareness activities along with affordable, accessible and socially acceptable services for those affected with presbyopia would be one of the key components of management.

Global disease burden of uncorrected refractive error among adolescents from 1990 to 2019

Background

To estimate the global disease burden of uncorrected refractive error (URE) among adolescents and assess the contributions of various risk factors to disability-adjusted life-years (DALYs) due to URE.

Methods

Global, regional and country-level DALY numbers and rates due to URE among adolescents were acquired from the Global Burden of Disease Study 2019 database. Human Development Index (HDI), Socio-Demographic Index (SDI) and other country-level data were obtained from other open databases as potential indicators. Regression analysis was used to evaluate associations between DALY rates among adolescents and potential predictors.

Results

Global DALYs due to URE among adolescents rose by 8% between 1990 and 2019 but moderately decreased by 4.8% during this period after adjusting for population size. Female adolescents showed higher DALY rates. DALY rates sharply increased from 5 to 9 years of age, then rose more slowly, reaching a plateau before 20 years of age. Country-level DALY rates in 2019 were positively associated with HDI, SDI, and urbanization rates but negatively correlated with primary school dropout rates. Higher disease burden of adolescents visually impaired from URE was associated with lower primary school dropout rates (β = − 0.257, 95% CI − 0.376 to − 0.138, P < 0.001) and higher urbanization rates (β = 0.257, 95% CI 0.067 to 0.256, P = 0.001).

Conclusions

Higher socioeconomic status, urbanization rates and education levels are associated with a heavier disease burden of URE among adolescents. The findings of this study can provide a reference for policy making on resource allocation for URE prevention and control in teenagers.

The prevalence and correlates of vision impairment and glasses ownership among ethnic minority and Han schoolchildren in rural China

PURPOSE

To determine the prevalence of visual impairment and glasses ownership among Han Chinese and Hui minority junior high school children in Ningxia Hui Autonomous Region, China.

DESIGN

Population-based cross-sectional study.

METHODS

Vision screening was conducted on 20,376 children (age 12-15 years) in all 124 rural junior high schools in Ningxia. Personal and family characteristics, glasses ownership, and academic performance were assessed through a survey questionnaire and standardized mathematics test, respectively.

RESULTS

The prevalence of visual acuity (VA) ≤6/12 in either eye was significantly higher among Han (54.5%) than Hui (45.2%) children (P<0.001), and was significantly positively associated with age, female sex, Han ethnicity, parental outmigration for work, shorter time spent outside during recess, shorter time spent watching television and higher time spent studying. Among children with VA≤6/12 in both eyes, only 56.8% of Han and 41.5% of Hui children had glasses (P<0.001). Glasses ownership was significantly associated with worse vision, greater family wealth, female sex, higher test scores, age, parental outmigration for work, understanding of myopia and glasses, higher time spent studying and Han ethnicity.

CONCLUSION

One of the first of its kind, this report on Han and Hui ethnic schoolchildren confirms a high prevalence of visual impairment among both populations, but slightly higher among the Han. Both groups, especially the Hui, have low rates of glasses ownership. Future interventions and policies designed to improve glasses usage should focus on populations with lower incomes and seek to correct erroneous beliefs about the safety of glasses and efficacy of traditional eye exercises.

Prevalence and factors associated with uncorrected presbyopia in a rural population of Japan: the Locomotive Syndrome and Health Outcome in Aizu Cohort Study

PURPOSE

To investigate the prevalence and factors associated with uncorrected presbyopia among rural community dwellers in Japan.

STUDY DESIGN

A population-based cross-sectional study was conducted in 2011 among community dwellers aged 40-74 years who received specific health checkups in Minamiaizu and Tadami, Fukushima Prefecture, Japan.

METHODS

Uncorrected presbyopia was considered as when the distance-corrected visual acuity in the better eye was ≥0.5 and the near-presenting visual acuity in the better eye was <0.4, regardless of distance refractive status. Multiple logistic regression analysis was employed to calculate the odds ratios (ORs) for uncorrected presbyopia and to adjust for possible confounders.

RESULTS

A total of 2054 individuals participated in the specific health checkups. In the 1156 individuals (response rate: 56.28%) analyzed in the study, the mean (SD) age was 63.0 (8.7) years, the percentage of women was higher (57.87%), and the prevalence of uncorrected presbyopia was 26.38% (95% CI 23.86%-29.03%). Multivariate analysis revealed that the factors associated with uncorrected presbyopia were older age (adjusted OR: 1.054 [95% CI: 1.034-1.075]), female sex (adjusted OR: 1.388 [95% CI: 1.006-1.915]), and distance-presenting vision impairment (adjusted OR: 2.651 [95% CI: 1.697-4.143]).

CONCLUSION

Approximately one-quarter of the participants in this study from a rural population of Japan did not have adequate near vision. It is recommended that a public health intervention should be enacted to correct presbyopia, especially in the older age group, women, and those with uncorrected refractive errors.

Prevalence of Uncorrected Refractive Error and Its Risk Factors; Tehran Geriatric Eye Study (TGES)

Purpose: To determine the age-sex-standardized prevalence of uncorrected refractive error and its determinantsMethods: This population-based cross-sectional study was conducted on 3310 people aged≥ 60 years in Tehran, Iran in 2019. Need for spectacles was defined as uncorrected visual acuity worse than 20/40 in better eye that could be corrected to more than 20/40 with suitable spectacles. Met need was defined as proportion of individuals with need for spectacles whose visual acuity was 20/40 or better with current spectacles. Unmet need was defined as proportion of individuals with need for spectacles who needed but did not have spectacles or their visual acuity was worse than 20/40 with current spectacles while suitable spectacles improved their visual acuity to 20/40 or better.Results: The age-sex-standardized prevalence of need for spectacles, met need, and unmet need was 16.67% (95% CI: 15.33-18.09), 7.81% (95% CI: 6.95-8.78), and 8.85% (95% CI: 7.77-10.07), respectively. Myopic subjects had the highest prevalence of need for spectacles (24.06%, 95% CI: 21.47-26.87). The odds ratio of met and unmet need in subjects≥ 80 years versus those aged 60-65 years was 0.36 (p-value: 0.009) and 2.34 (p-value: <0.001), respectively. The odds ratio of met and unmet need in subjects with a university education versus illiterate subjects was 1.72 (p-value: 0.045) and 0.42 (p-value: 0.007), respectively.Conclusion: The prevalence of uncorrected refractive error was lower in this study compared to previous studies. The met need rate was lower in subjects with older age and lower education levels.

Near-vision impairment and effective near-vision spectacle coverage in two districts in Telangana, India: a population-based cross-sectional study

OBJECTIVES

To investigate the prevalence of near-vision impairment (NVI) and effective spectacle coverage for near vision in those aged ≥40 years in Khammam and Warangal district in Telangana, India.

DESIGN

A population-based cross-sectional study.

SETTING

Khammam and Warangal district in Telangana, India.

PARTICIPANTS

Of 6000 people enumerated, 5357 were examined (89%). 4526 participants without distance vision impairment were included in the analysis.

MAIN OUTCOME MEASURES

The study teams visited selected households and conducted eye examinations. NVI was defined as binocular presenting near vision worse than N6. 'Unmet need' was deemed to be present if the unaided near vision was worse than N6 and improved to N6 with near correction among the participants who did not have spectacles for near vision. 'Met need' was deemed to be present when unaided near vision was worse than N6 but improving to N6 with their spectacles. The 'undermet need' was deemed to be present when aided near vision was worse than N6 but improved to N6 with correction. Based on these definitions, e-near-vision coverage (%) is calculated as follows: e-NVC (%)=met need/(met need+undermet need+unmet need) × 100.

RESULTS

The mean age was 53.5 years (SD: 10.8 years), 2534/4526 (55.8%) were women, 1819/4526 (41.8%) had at least primary school education and 2368/4526 (52.3%) were from the Khammam district. The prevalence of NVI was 55.8% (95% CI 72.5 to 75.1; n=3343). Overall, the e-NVC (%) was 31.8%. It was 40.0% in Khammam and 23.2% in Warangal.

CONCLUSION

NVI is common in Khammam and Warangal districts in Telangana with inadequate effective near-vision coverage. Effective service delivery models are needed to reach out and provide services to address NVI to achieve universal eye health coverage in the region.

Patient and Economic Burden of Presbyopia: A Systematic Literature Review

Purpose

The objective of this systematic literature review (SLR) was to collate, report, and critique published evidence related to epidemiology and patient and economic burden of presbyopia.

Patients and Methods

A systematic literature search was conducted in MEDLINE^®, Embase^®, and Cochrane Library databases from the time of inception through October 2018 using Cochrane methodology. Studies published in English language reporting on epidemiology and patient and economic burden of presbyopia were included.

Results

Initial systematic literature search yielded 2,228 citations, of which 55 met the inclusion criteria (epidemiology, 44; patient burden, 14; economic burden, 1) and were included in this review. Globally, 1.09 billion people are estimated to be affected by presbyopia. The reported presbyopia prevalence varied across regions and by age groups, with the highest prevalence of 90% reported in the Latin America region in adults ≥35 years. Presbyopic patients report up to 22% decrease in quality-of-life (QoL) score, and up to 80% patients with uncorrected presbyopia report difficulty in performing near-vision related tasks. About 12% of presbyopes required help in performing routine activities, and these visual limitations reportedly induce distress and low self-esteem in presbyopia patients. Uncorrected presbyopia led to a 2-fold increased difficulty in near-vision-related tasks and a >8-fold increased difficulty in very demanding near-vision-related tasks. Further, uncorrected presbyopia leads to a decrement in patients’ QoL, evident by the low utility values reported in the literature. Annual global productivity losses due to uncorrected and under-corrected presbyopia in working-age population (<50 years) were estimated at US$ 11 billion (0.016% of the global domestic product (GDP) in 2011, which increased to US$ 25.4 billion if all people aged <65 years were assumed to be productive.

Conclusion

Uncorrected presbyopia affects patients’ vision-related quality of life due to difficulty in performing near-vision-related tasks. In addition, un-/under-corrected presbyopia could lead to productivity losses in working-age adults.

Use of spectacles for distance vision: coverage, unmet needs and barriers in a rural area of North India

Background

Uncorrected refractive errors contribute enormously to the burden of avoidable visual impairment worldwide. There is a huge disparity in different parts of the globe in context to spectacle coverage for distance vision. This study was undertaken with objectives of determining prevalence of spectacle coverage, unmet needs and associated factors among adults in a rural community of north India.

Methods

A community-based cross-sectional study was carried out within selected clusters of Jhajjar district of Haryana. All participants aged > 15 years underwent visual acuity assessment by LogMAR “E” screening chart. Participants with presenting visual acuity < 6/12 in any eye and all current spectacle users underwent detailed ophthalmic examination and refraction. Additional details about spectacles, barriers for their use and willingness to pay for them were collected. Participants with met and unmet need for spectacle use at visual acuity > 6/12 was computed. These are reported as proportions with 95% confidence intervals. Associated factors with unmet need were determined using bivariable and multivariable logistic regression analysis.

Results

A total of 6910 participants were examined. The current spectacle use was 7.5% (95% Confidence Interval CI: 6.5, 8.7). The spectacle coverage was found in 33.3% (95% CI: 30.0, 36.7) participants among those in need. The unmet need was found in 10.8% of participants (95% CI: 10.1, 11.6). On multivariable analysis, odds of unmet need was associated with age, gender, level of education and marriage status. The most common barrier for refractive correction was lack of perceived need for refraction and its correction.

Conclusion

There is substantial unmet need for distance vision spectacles in this population. It is imperative that multi-component intervention be implemented to improve spectacle coverage in this rural north Indian setting.

Temporal trends in the prevalence of spectacle use and spectacle coverage in India

BACKGROUND

This study aims to assess the temporal trends in the prevalence of spectacle use and spectacle coverage for refractive errors in population-based studies conducted during 2011-2012 and 2017 among those aged ≥ 40 years in the state of Telangana, India. An intervention in the form of 10 vision centres and a secondary centre was established in one district (Khammam) after the 2011-2012 study and another district (Warangal) was left to secular trends.

METHODS

In both the studies, multi-stage cluster random sampling methodology was used to select the participants. In addition to a clinical examination, a questionnaire was used for collecting information on current and previous use of spectacles, type of spectacles and details of the spectacle providers. The same questionnaire was used in both the studies.

RESULTS

In total, 2,485 participants were examined in the 2011-2012 study and 2,711 participants were examined in the 2017 study in Khammam. Similarly, 2,438 and 2,646 participants were examined in Warangal in the two studies, respectively. In Khammam, the age and gender-adjusted prevalence of current spectacle use increased from 30.0 per cent (95% CI 28.2-31.9) to 34.8 per cent (95% CI 33.0-36.6) in the 2011-2012 and 2017 studies, respectively (p < 0.01). However, in the Warangal district, the age and gender-adjusted prevalence of current spectacle use declined from 32.8 per cent (95% CI 31.0-34.7) to 27.6 per cent (95% CI 25.9-29.3) during the 2011-2012 and 2017 studies, respectively (p < 0.01). In Khammam, the spectacle coverage increased from 26.9 per cent to 35.6 per cent, but it declined from 43.8 per cent to 35.7 per cent in Warangal between the studies in 2011-2012 and 2017.

CONCLUSIONS

An increase in spectacle use and coverage was observed in Khammam where the secondary centre and vision centres were established, compared to Warangal where there was no such intervention. The results suggest a positive impact of the intervention in the Khammam district and suggest replication of the model to address the burden of uncorrected refractive errors.

Prevalence of refractive errors, uncorrected refractive error, and presbyopia in adults in India: A systematic review

Purpose:

The objective of this review is to estimate the prevalence of refractive errors, uncorrected refractive error (URE), and uncorrected presbyopia in adults aged ≥30 years in India.

Methods:

The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed. A detailed literature search was performed to include all studies published from India from the year 1990 using the Cochrane Library, Medline, and Embase. Refractive error was defined by >0.50 D ametropia. URE was defined by presenting visual acuity (PVA) worse than 6/18 improving with pinhole or spectacle correction, and uncorrected presbyopia by near vision <N8 improving with correction in the absence of distance URE.

Results:

Fifteen studies were included from South India, one each from Western and Central India, and one study covered 15 states across India. The prevalence of RE of at least 0.50 D of spherical equivalent ametropia was 53.1% [(95% confidence interval (CI): 37.2–68.5), of which myopia and hyperopia was 27.7% and 22.9%, respectively. The prevalence of URE was 10.2% (95% CI: 6.9–14.8), but heterogeneity in these estimates was very high. The prevalence of uncorrected presbyopia was 33% (95% CI: 19.1–51.0).

Conclusion:

This review highlights the magnitude of refractive errors among adults in India. More studies are needed using standard methods in regions where there is a lack of information on UREs. Programs delivering spectacles for adults in India will need to primarily focus on reading glasses to correct presbyopia along with spectacles for hyperopia and myopia.

Temporal trends in the prevalence and causes of visual impairment in the South Indian state of Telangana: a population-based cross-sectional study

OBJECTIVES

To investigate the temporal trends in the prevalence and causes of visual impairment (VI) in South India.

DESIGN

Population-based cross-sectional studies conducted during the years 2011-2012 and 2017 using identical study methods and in geographical locations are compared. The L V Prasad Eye Institute established services in Khammam and not in Warangal district after the 2011-2012 study.

SETTING

Khammam and Warangal districts in Telangana, India.

PARTICIPANTS

In total, 5357 participants aged ≥40 years were examined from two districts in the 2011-2012 study and 4923 participants were examined in the 2017 study.

MAIN OUTCOME MEASURES

Age-adjusted and gender-adjusted temporal trends in the prevalence and causes of VI.Blindness and moderate VI (MVI) were defined as presenting visual acuity worse than 6/60 and 6/18-6/60 in the better eye, respectively. VI included MVI and blindness.

RESULTS

Nearly 2500 participants were examined in each location in both the 2011-2012 and 2017 studies. In Khammam district, overall VI declined by 2.5% from 15.5% to 13.0% (p<0.001). While there was no significant change in MVI (p=0.566), blindness declined by 3.0% from 5.4% to 2.4% (p<0.001). In Warangal district, the overall VI remained unchanged (p=0.60). While MVI increased by 3% from 9.3% to 12.3% (p=0.001), blindness declined by 3.5% from 6.5% to 3.0% (p<0.001). While MVI due to cataract increased in both districts, there was a significant decline in MVI due to refractive errors in Khammam.

CONCLUSION

There was a significant decline in VI in Khammam district but not in Warangal district. The differential trends in prevalence and causes of VI can be explained by the availability and uptake of eye care services in these two districts.

Rapid assessment of avoidable blindness in Papua New Guinea: a nationwide survey

Objective

To estimate the prevalence and main causes of blindness and vision impairment in people aged 50 years and older in Papua New Guinea (PNG).

Design

National cross-sectional population-based survey in National Capital District (NCD), Highlands, Coastal and Islands regions.

Methods

Adults aged 50 years and above were recruited from 100 randomly selected clusters. Each participant underwent monocular presenting and pinhole visual acuity (VA) assessment and lens examination. Those with pinhole VA<6/12 in either eye had a dilated fundus examination to determine the primary cause of reduced vision. Those with obvious lens opacity were interviewed on barriers to cataract surgery.

Results

A total of 4818 adults were examined. The age-adjusted and sex-adjusted prevalence of blindness (VA <3/60), severe vision impairment (SVI, VA <6/60 but ≥3/60), moderate vision impairment (MVI, VA <6/18 but ≥6/60) and early vision impairment (EVI, VA <6/12 but ≥6/18) was 5.6% (95% CI 4.9% to 6.3%), 2.9% (95% CI 2.5% to 3.4%), 10.9% (95% CI 9.9% to 11.9%) and 7.3% (95% CI 6.6% to 8.0%), respectively. The main cause of blindness, SVI and MVI was cataract, while uncorrected refractive error was the main cause of EVI. A significantly higher prevalence of blindness, SVI and MVI occurred in the Highlands compared with NCD. Across all regions, women had lower cataract surgical coverage and spectacle coverage than men.

Conclusions

PNG has one of the highest reported prevalence of blindness globally. Cataract and uncorrected refractive error are the main causes, suggesting a need for increased accessible services with improved resources and advocacy for enhancing eye health literacy.

Early Intervention and Nonpharmacological Therapy of Myopia in Young Adults

Myopia is a condition of the eye where parallel rays focus in front of, instead of on, the retina, which results in excessive refractive power of the cornea or the lens or eyeball elongation. Studies carried out in recent years show that the etiology of myopia is complex with genetic and environmental factors playing a role. Refraction defects decrease the quality of vision, while progressing myopia can lead to partial loss of vision, which can be particularly dramatic in young adults. Therefore, it is so crucial to take appropriate actions aimed at preventing myopia progression. This is a review of nonpharmacological therapeutic possibilities of refraction defect prevention in young adults, with special regard to myofascial therapy, osteopathy, and massage of acupuncture points surrounding the eye.

Spectacles use in a rural population in the state of Telangana in South India

CONTEXT

Uncorrected refractive errors are the leading cause of visual impairment.

AIMS

To assess the prevalence and patterns of spectacles use among those aged ≥40 years in the South Indian state of Telangana.

SETTINGS AND DESIGN

This was a population-based, cross-sectional study, in which 6150 people were enumerated from 123 clusters in the two districts of Telangana state (Adilabad and Mahbubnagar) using a two-stage cluster random sampling methodology.

MATERIALS AND METHODS

Participants were visited in their households and presenting visual acuity (VA) was assessed in all cases followed by pinhole VA if presenting VA was worse than 6/12. A questionnaire was used to collect information on the current and previous spectacles use, type of spectacles, and details of the spectacles provider.

STATISTICAL ANALYSIS USED

Stata statistical software version 12.

RESULTS

Among 5881 participants examined, 53.7% were women, and 82% had no formal education. The prevalence of current spectacles use was 28.8% (95% confidence interval: 27.6-30.0). On applying multiple logistic regression analysis, spectacles use was significantly associated with older age groups, female gender, higher levels of education, and residing in Adilabad district. Bifocals were the most commonly used type of spectacles (56.3%), and private eye clinics (70.3%) were the leading service providers. The spectacles coverage was 53.6%.

CONCLUSIONS

We reported on prevalence and patterns of spectacles use using a large representative sample and a high response rate. More than half of those who may benefit from spectacles were using them, suggestive of a reasonable primary eye care coverage in the two districts studied.

Prevalence of visual impairment due to uncorrected refractive error: Results from Delhi-Rapid Assessment of Visual Impairment Study

AIM

To estimate the prevalence of visual impairment (VI) due to uncorrected refractive error (URE) and to assess the barriers to utilization of services in the adult urban population of Delhi.

MATERIALS AND METHODS

A population-based rapid assessment of VI was conducted among people aged 40 years and above in 24 randomly selected clusters of East Delhi district. Presenting visual acuity (PVA) was assessed in each eye using Snellen's "E" chart. Pinhole examination was done if PVA was <20/60 in either eye and ocular examination to ascertain the cause of VI. Barriers to utilization of services for refractive error were recorded with questionnaires.

RESULTS

Of 2421 individuals enumerated, 2331 (96%) individuals were examined. Females were 50.7% among them. The mean age of all examined subjects was 51.32 ± 10.5 years (standard deviation). VI in either eye due to URE was present in 275 individuals (11.8%, 95% confidence interval [CI]: 10.5-13.1). URE was identified as the most common cause (53.4%) of VI. The overall prevalence of VI due to URE in the study population was 6.1% (95% CI: 5.1-7.0). The elder population as well as females were more likely to have VI due to URE (odds ratio [OR] = 12.3; P < 0.001 and OR = 1.5; P < 0.02). Lack of felt need was the most common reported barrier (31.5%).

CONCLUSIONS

The prevalence of VI due to URE among the urban adult population of Delhi is still high despite the availability of abundant eye care facilities. The majority of reported barriers are related to human behavior and attitude toward the refractive error. Understanding these aspects will help in planning appropriate strategies to eliminate VI due to URE.

Near visual impairment and spectacle coverage in Telangana, India

IMPORTANCE

The study highlights the burden of near visual impairment (NVI) in India.

BACKGROUND

NVI is a common condition that can be addressed through provision of spectacles. The study aims to assess the prevalence of NVI and spectacle coverage among those aged ≥40 years in south Indian state of Telangana.

DESIGN

Population-based cross-sectional study using a rapid assessment methodology.

PARTICIPANTS

Five thousand one hundred forty participants enumerated from 123 clusters in two districts and have presenting distance visual acuity of ≥6/18 in the better eye.

METHODS

Presenting near vision was assessed binocularly at a fixed distance of 40 cm using a log MAR chart with tumbling E optotypes in ambient lighting conditions. If the presenting near vision was worse than 6/12 (log MAR 0.3), then it was re-assessed with addition lens appropriate to the age. NVI was defined as binocular presenting near vision worse than 6/12.

MAIN OUTCOME MEASURES

Prevalence of NVI and spectacle coverage.

RESULTS

The mean age of the participants was 51.1 years (standard deviation: 9.3 years), and 46.5% (n = 2392) were women. About 80% (n = 4142) of them had no education, and 21.9% (n = 1126) were using spectacles for near vision. Nearly half of the participants were from Adilabad district (n = 2665). The prevalence of NVI was 58.3% (95% confidence interval: 56.9-59.6). NVI was associated with older age groups, male gender and no education. The spectacle coverage was 26.5%.

CONCLUSIONS AND RELEVANCE

NVI is common in rural Telangana with low spectacle coverage. Service delivery programs should use a multi-pronged approach to address the burden of NVI.

The prevalence of uncorrected refractive errors in underserved rural areas

Purpose

To determine the prevalence of uncorrected refractive errors, need for spectacles, and the determinants of unmet need in underserved rural areas of Iran.

Methods

In a cross-sectional study, multistage cluster sampling was done in 2 underserved rural areas of Iran. Then, all subjects underwent vision testing and ophthalmic examinations including the measurement of uncorrected visual acuity (UCVA), best corrected visual acuity, visual acuity with current spectacles, auto-refraction, retinoscopy, and subjective refraction. Need for spectacles was defined as UCVA worse than 20/40 in the better eye that could be corrected to better than 20/40 with suitable spectacles.

Results

Of the 3851 selected individuals, 3314 participated in the study. Among participants, 18.94% [95% confidence intervals (CI): 13.48–24.39] needed spectacles and 11.23% (95% CI: 7.57–14.89) had an unmet need. The prevalence of need for spectacles was 46.8% and 23.8% in myopic and hyperopic participants, respectively. The prevalence of unmet need was 27% in myopic, 15.8% in hyperopic, and 25.46% in astigmatic participants. Multiple logistic regression showed that education and type of refractive errors were associated with uncorrected refractive errors; the odds of uncorrected refractive errors were highest in illiterate participants, and the odds of unmet need were 12.13, 5.1, and 4.92 times higher in myopic, hyperopic and astigmatic participants as compared with emmetropic individuals.

Conclusion

The prevalence of uncorrected refractive errors was rather high in our study. Since rural areas have less access to health care facilities, special attention to the correction of refractive errors in these areas, especially with inexpensive methods like spectacles, can prevent a major proportion of visual impairment.

The met and unmet need for refractive correction and its determinants in 7-year-old children

Refractive errors are the leading cause of visual impairment and at the same time the most treatable cause of visual impairment in children and students. The aim of this study is to determine the prevalence of the unmet need for refractive correction and the spectacle coverage rate among 7-year-old Iranian children with refractive errors. The present cross-sectional study was performed in 2013 through multistage cluster sampling across eight cities in Iran. For all students, noncycloplegic autorefraction was done by a technician. The unmet need for glasses was defined as the ratio of people who did not have glasses or their vision with their current glasses was worse than 6/12 despite achieving 6/12 or better visual acuity with proper correction. A total of 67 schools were selected by multistage cluster sampling; 4106 subjects participated in the study (response rate, 89%), and 48.2% ( n = 1979) were girls. The prevalence of spectacle need was 4.11% (95% confidence interval [CI: 3.19–5.04]), the unmet need was 2.74% (95% CI [1.89–3.59]), and the spectacle coverage rate (met need/[met need + unmet need]) was 33.3%. Also, the unmet need in children whose families were in the lower income quartile was 7.14 times the rate seen in children in the upper income quartile. The concentration index for the unmet need was −.27 (±.05). The findings of this study confirm that in light of the detrimental effects of refractive errors in schoolchildren’s academic progress and their future, identification of the students who live in poorer families and have multiple risk factors for developing vision disorders should be a health priority.

Spectacle coverage and spectacles use among elderly population in residential care in the south Indian state of Andhra Pradesh

Background. There is limited research conducted on uncorrected refractive errors, presbyopia, and spectacles use among the elderly population in residential care in developing countries such as India. We conducted a cross-sectional study among elderly in residential care to assess the spectacle coverage and spectacles usage in the south Indian state of Andhra Pradesh. Methods. All 524 residents in the 26 “homes for aged” institutions in the district were enumerated. Eye examination was performed that included visual acuity (VA) assessment for distant and near vision. A questionnaire was used to collect information on spectacles use. Results. 494/524 individuals were examined, 78% were women, and 72% had no education. The mean age of participants was 70 years. The spectacle coverage for refractive errors was 35.1% and 23.9% for presbyopia. The prevalence of current use and past use of spectacles was 38.5% (95% CI: 34.2–42.8; n = 190) and 17.2% (95% CI: 13.9–42.8), respectively. Conclusions. There is low spectacle coverage for both refractive errors and presbyopia among elderly individuals in residential care in the south Indian state of Andhra Pradesh. Appropriate service delivery systems should be developed to reach out this vulnerable group of seniors on a priority basis.

Presbyopia, spectacles use and spectacle correction coverage for near vision among cloth weaving communities in Prakasam district in South India

PURPOSE

To assess the prevalence of presbyopia, spectacles use and spectacle correction coverage for near vision among weaving communities in Prakasam district in the South Indian state of Andhra Pradesh.

METHODS

A population based cross sectional study was conducted among a population aged ≥40 years. Distance visual acuity was assessed at 6 m. Near vision was assessed using N notation charts at a fixed distance of 40 cm. Presbyopia was defined as binocular unaided near vision <N8 and improving to ≥N8 with near addition lenses. Functional presbyopia was defined as presenting near vision <N8 and improving to ≥N8 with near addition lenses. A questionnaire was used to collect information on spectacles use. In order to calculate spectacle correction coverage for presbyopia, met presbyopia need was defined as the percentage of people who presented with presbyopia correction and achieved binocular N8 using it. Unmet presbyopia need was defined as the percentage of people who had either under corrected or uncorrected binocular near vision worse than N8 that would improve with correction to at least N8.

RESULTS

Of 2848/3000 enumerated subjects (94.0%) participated. Four hundred individuals with distance visual impairment were excluded from the analysis. Among the remaining 2448 individuals, 46% were male and 49.1% had no formal education. The mean age among males was higher compared to females (p < 0.01). Based on unaided near vision, the prevalence of presbyopia was 61.8% (95% CI: 59.9-63.7) and the prevalence of functional presbyopia was 35.1% (95% CI: 33.2-37.0). Using multivariable analysis, it was found that functional presbyopia was significantly associated with female gender, no education and lack of spectacle use. Spectacle correction coverage was 43.2%. Among the 781 individuals who had no correction at the time of examination, 122 (15.6%) subjects reported having used spectacles previously. The reasons for discontinuation of spectacles were discomfort with spectacles (n = 57; 46.7%), damaged or lost spectacles (n = 45; 36.9%), ability to see clearly even without spectacles (n = 12; 9.8%) and other reasons (n = 8; 6.6%).

CONCLUSION

Although the prevalence of presbyopia (61.8%) was comparable with other studies, the prevalence of functional presbyopia (35.1%) was lower and linked with higher spectacle correction coverage (43.2%) in this weaving community. However, it still highlights a large unmet need and spectacle correction coverage that could be improved by the provision of good quality, affordable spectacles, which may also improve spectacles use.

Integrated model of primary and secondary eye care for underserved rural areas: the L V Prasad Eye Institute experience

Blindness is a major global public health problem and recent estimates from World Health Organization (WHO) showed that in India there were 62 million visually impaired, of whom 8 million are blind. The Andhra Pradesh Eye Disease Study (APEDS) provided a comprehensive estimate for prevalence and causes of blindness for the state of Andhra Pradesh (AP). It also highlighted that uptake of services was also an issue, predominantly among lower socio-economic groups, women, and rural populations. On the basis of this analysis, L V Prasad Eye Institute (LVPEI) developed a pyramidal model of eye care delivery. This article describes the LVPEI eye care delivery model. The article discusses infrastructure development, human resource development, and service delivery (including prevention and promotion) in the context of primary and secondary care service delivery in rural areas. The article also alludes to opportunities for research at these levels of service delivery and the amenability of the evidence generated at these levels of the LVPEI eye health pyramid for advocacy and policy planning. In addition, management issues related to the sustainability of service delivery in rural areas are discussed. The article highlights the key factors required for the success of the LVPEI rural service delivery model and discusses challenges that need to be overcome to replicate the model. The article concludes by noting the potential to convert these challenges into opportunities by integrating certain aspects of the existing healthcare system into the model. Examples include screening of diabetes and diabetic retinopathy in order to promote higher community participation. The results of such integration can serve as evidence for advocacy and policy.