Prevalence of Refractive Errors in a Population of Office-Workers in Buenos Aires, Argentina

Outdoor exposure in children from Buenos Aires Province, Argentina

OBJECTIVES

To evaluate myopia risk factors, mainly outdoor exposure and reading habits, in a country with low prevalence of myopia (Buenos Aires Province, Argentina).

METHODS

Consecutive children interviewed in a clinical private practice setting were autorefracted under cycloplegia with cyclopentolate 1%. Their parents consented to fill a questionnaire about schooling, tutorial classes, outdoor exposure, reading habits, and cellphone use, both on weekdays and weekends. The Spanish questionnaire was based on past English questionnaires of myopia clinical trials. The spherical equivalent of the right eye was used for the refractive distribution. The average daily hours spent for each activity were calculated.

RESULTS

This study involved 115 children aged 10.48 ± 3.65 years (range 5-18 years), with 56.5% being girls. Children had 8 h of schooling per day in 62.6% of cases, and only 14.8 % had tutorial classes after school. There were 38.3% myopes (<-0.50 D), 24.3% hyperopes (>+2.00 D) and the rest were emmetropes. The mean time that these children spent outdoors per day was 3.94 ± 1.45 h (27.60 ± 10.16 h per week). The total mean time spent reading and writing per day was 1.50 ± 0.98 h, and that spent using cellphones and tablets was 2.43 ± 1.66 h.

CONCLUSION

In an environment with low myopia prevalence, children spend almoast 4 h per day outdoors, much more than the usual recommendation of 2 h a day for myopia prevention.

Prevalence of refractive errors and color vision deficiency in a population of industry-workers in Abhar, Iran

Visual impairment due to refractive errors and color vision deficiency (CVD) can affect the visual abilities of workers in workplace. Identifying the prevalence of common visual problems helps us to prevent and treat occupational ocular problems.This study was conducted on 2600 males referring from companies for a routine medical exam to Occupational Medicine Center. In all subjects, visual acuity and refraction were measured. Assessment of color vision was performed by Ishihara color test. In present study, right eyes of subjects were selected to statistical analysis.The mean spherical equivalent was -0.19 ± 1.39 diopter with a range of -11.00 to +10.00 diopter. Whereas 71% of persons were emmetropic, 20% and 9% of them were myopic and hypermetropic, respectively. From a total subjects, 164 of them had CVD with prevalence of color blindness of 6.3%. In comparison with normal subjects, CVD had no significant effect on refractive findings of our subjects (P > .05).Our data present the prevalence of refractive errors and color blindness among Iranian industry-workers. Compared with other studies, our subjects have a lower prevalence of refractive errors, and similar rate of prevalence of color blindness.

Application of big-data for epidemiological studies of refractive error

PURPOSE

To examine whether data sourced from electronic medical records (EMR) and a large industrial spectacle lens manufacturing database can estimate refractive error distribution within large populations as an alternative to typical population surveys of refractive error.

SUBJECTS

A total of 555,528 patient visits from 28 Irish primary care optometry practices between the years 1980 and 2019 and 141,547,436 spectacle lens sales records from an international European lens manufacturer between the years 1998 and 2016.

METHODS

Anonymized EMR data included demographic, refractive and visual acuity values. Anonymized spectacle lens data included refractive data. Spectacle lens data was separated into lenses containing an addition (ADD) and those without an addition (SV). The proportions of refractive errors from the EMR data and ADD lenses were compared to published results from the European Eye Epidemiology (E3) Consortium and the Gutenberg Health Study (GHS).

RESULTS

Age and gender matched proportions of refractive error were comparable in the E3 data and the EMR data, with no significant difference in the overall refractive error distribution (χ2 = 527, p = 0.29, DoF = 510). EMR data provided a closer match to the E3 refractive error distribution by age than the ADD lens data. The ADD lens data, however, provided a closer approximation to the E3 data for total myopia prevalence than the GHS data, up to age 64.

CONCLUSIONS

The prevalence of refractive error within a population can be estimated using EMR data in the absence of population surveys. Industry derived sales data can also provide insights on the epidemiology of refractive errors in a population over certain age ranges. EMR and industrial data may therefore provide a fast and cost-effective surrogate measure of refractive error distribution that can be used for future health service planning purposes.

A Review of Current Concepts of the Etiology and Treatment of Myopia

Myopia occurs in more than 50% of the population in many industrialized countries and is expected to increase; complications associated with axial elongation from myopia are the sixth leading cause of blindness. Thus, understanding its etiology, epidemiology, and the results of various treatment regiments may modify current care and result in a reduction in morbidity from progressive myopia. This rapid increase cannot be explained by genetics alone. Current animal and human research demonstrates that myopia development is a result of the interplay between genetic and the environmental factors. The prevalence of myopia is higher in individuals whose both parents are myopic, suggesting that genetic factors are clearly involved in myopia development. At the same time, population studies suggest that development of myopia is associated with education and the amount time spent doing near work; hence, activities increase the exposure to optical blur. Recently, there has been an increase in efforts to slow the progression of myopia because of its relationship to the development of serious pathological conditions such as macular degeneration, retinal detachments, glaucoma, and cataracts. We reviewed meta-analysis and other of current treatments that include: atropine, progressive addition spectacle lenses, orthokeratology, and multifocal contact lenses.

Global and regional estimates of prevalence of refractive errors: Systematic review and meta-analysis

Purpose

The aim of the study was a systematic review of refractive errors across the world according to the WHO regions.

Methods

To extract articles on the prevalence of refractive errors for this meta-analysis, international databases were searched from 1990 to 2016. The results of the retrieved studies were merged using a random effect model and reported as estimated pool prevalence (EPP) with 95% confidence interval (CI).

Results

In children, the EPP of myopia, hyperopia, and astigmatism was 11.7% (95% CI: 10.5–13.0), 4.6% (95% CI: 3.9–5.2), and 14.9% (95% CI: 12.7–17.1), respectively. The EPP of myopia ranged from 4.9% (95% CI: 1.6–8.1) in South–East Asia to 18.2% (95% CI: 10.9–25.5) in the Western Pacific region, the EPP of hyperopia ranged from 2.2% (95% CI: 1.2–3.3) in South-East Asia to 14.3% (95% CI: 13.4–15.2) in the Americas, and the EPP of astigmatism ranged from 9.8% in South-East Asia to 27.2% in the Americas. In adults, the EPP of myopia, hyperopia, and astigmatism was 26.5% (95% CI: 23.4–29.6), 30.9% (95% CI: 26.2–35.6), and 40.4% (95% CI: 34.3–46.6), respectively. The EPP of myopia ranged from 16.2% (95% CI: 15.6–16.8) in the Americas to 32.9% (95% CI: 25.1–40.7) in South-East Asia, the EPP of hyperopia ranged from 23.1% (95% CI: 6.1%–40.2%) in Europe to 38.6% (95% CI: 22.4–54.8) in Africa and 37.2% (95% CI: 25.3–49) in the Americas, and the EPP of astigmatism ranged from 11.4% (95% CI: 2.1–20.7) in Africa to 45.6% (95% CI: 44.1–47.1) in the Americas and 44.8% (95% CI: 36.6–53.1) in South-East Asia. The results of meta-regression showed that the prevalence of myopia increased from 1993 (10.4%) to 2016 (34.2%) (P = 0.097).

Conclusion

This report showed that astigmatism was the most common refractive errors in children and adults followed by hyperopia and myopia. The highest prevalence of myopia and astigmatism was seen in South-East Asian adults. The highest prevalence of hyperopia in children and adults was seen in the Americas.

The prevalence of refractive errors among adult rural populations in Iran

PURPOSE

The aim was to determine the prevalence of myopia and hyperopia and related factors in underserved rural areas in Iran.

METHODS

Under random cluster sampling, two rural regions were randomly selected in the north and southwest of the country, and 3,061 persons over 15 years of age were invited into the study. After selecting samples, all participants had refraction, measurement of uncorrected vision and visual acuity and ocular health examination by slitlamp biomicroscopy.

RESULTS

Of the 3,061 invitees, 2,575 participated in the study (response rate: 84.1 per cent). After excluding those who met the exclusion criteria or had missing refractive data, eventually there were 2,518 subjects available for this analysis. The mean age of the participants was 44.3 ± 17.5 years (range: 16 to 93 years) and 1,460 of them (58.0 per cent) were female. The overall prevalence of myopia and hyperopia in this study was 25.2 per cent (95 per cent CI: 23.2 to 27.2) and 22.5 per cent (95 per cent CI: 20.6 to 24.4), respectively. The prevalence of myopia increased from 20.9 per cent in participants 16 to 20 years to 32.9 per cent in the 21 to 30 years age group, declined up to the age of 60 years and increased again afterwards. The lowest prevalence was 6.8 per cent observed in the 16 to 20 years age group and the highest was 45.8 per cent in 61- to 70-year-olds. In the final logistic regression model, myopia significantly associated with age, higher education levels and cataracts, while hyperopia associated with age, lower education levels and male gender.

CONCLUSION

In our study, the prevalence of myopia was lower and the prevalence of hyperopia was higher compared to most previous studies. The findings of this study imply that refractive errors vary by age.

Myopia and international educational performance

PURPOSE

To analyse the relationship between myopia, educational performance and engagement in after-school tutorial classes.

METHODS

Educational performance data and data on engagement in after-school tutorial classes were taken from the results of the Organisation for Economic Cooperation and Development (OECD) Program in Secondary Assessment (PISA) reports for 2009, which tested educational outcomes in representative samples of 15 year-old school children from 65 jurisdictions. High prevalence of myopia (>70%) and low prevalence of myopia (<40%) locations were identified by systematic literature search.

RESULTS

Six locations with a high prevalence of myopia were identified from among the participants in PISA 2009 - Shanghai-China, Hong Kong-China, Taiwan, Singapore, Japan and South Korea. All were ranked in the top quartile on educational performance. Other participants in the top educational performance quartile were identified as locations with a low prevalence of myopia, including Australia and Finland. The locations with a high prevalence of myopia combined high educational performance and high engagement in after-school tutorials, whereas the locations with a low prevalence of myopia combined high educational performance with little engagement in tutorials.

DISCUSSION

These results show that it is possible to achieve high educational outcomes without extensive engagement in after-school tutorials, and that the combination of high educational outcomes with extensive use of tutorials is associated with high prevalence rates of myopia. We suggest that extensive use of after-school tutorials may be a marker of educational environments which impose high educational loads. Further quantification of educational loads to include after- school educational activities, such as homework, tutorials and other after-school classes, as well as formal school classes, is desirable. Policy initiatives to decrease these loads may contribute to the prevention of myopia, perhaps, at least in part, by enabling children to spend more time outdoors.

Population-based survey of refractive error among school-aged children in rural northern China: the Heilongjiang eye study

BACKGROUND

The prevalence of refractive error in the north of China is unknown. The study aimed to estimate the prevalence and associated factors of refractive error in school-aged children in a rural area of northern China.

DESIGN

Cross-sectional study.

PARTICIPANTS OR SAMPLES

The cluster random sampling method was used to select the sample.

METHODS

A total of 1700 subjects of 5 to 18 years of age were examined. All participants underwent ophthalmic evaluation. Refraction was performed under cycloplegia. Association of refractive errors with age, sex, and education was analysed.

MAIN OUTCOME MEASURES

The main outcome measure was prevalence rates of refractive error among school-aged children.

RESULTS

Of the 1700 responders, 1675 were eligible. The prevalence of uncorrected, presenting, and best-corrected visual acuity of 20/40 or worse in the better eye was 6.3%, 3.0% and 1.2%, respectively. The prevalence of myopia was 5.0% (84/1675, 95% CI, 4.8%-5.4%) and of hyperopia was 1.6% (27/1675, 95% CI, 1.0%-2.2%). Astigmatism was evident in 2.0% of the subjects. Myopia increased with increasing age, whereas hyperopia and astigmatism were associated with younger age. Myopia, hyperopia and astigmatism were more common in females. We also found that prevalence of refractive error were associated with education. Myopia and astigmatism were more common in those with higher degrees of education.

CONCLUSION

This report has provided details of the refractive status in a rural school-aged population. Although the prevalence of refractive errors is lower in the population, the unmet need for spectacle correction remains a significant challenge for refractive eye-care services.

High prevalence of refractive errors in a rural population: 'Nooravaran Salamat' Mobile Eye Clinic experience

BACKGROUND

The prevalence of myopia and hyperopia and determinants were determined in a rural population of Iran.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

Using random cluster sampling, 13 of the 83 villages of Khaf County in the north east of Iran were selected. Data from 2001 people over the age of 15 years were analysed.

METHODS

Visual acuity measurement, non-cycloplegic refraction and eye examinations were done at the Mobile Eye Clinic.

MAIN OUTCOME MEASURES

The prevalence of myopia and hyperopia based on spherical equivalent worse than -0.5 dioptre and +0.5 dioptre, respectively.

RESULTS

The prevalence of myopia, hyperopia and anisometropia in the total study sample was 28% (95% confidence interval: 25.9-30.2), 19.2% (95% confidence interval: 17.3-21.1), and 11.5% (95% confidence interval: 10.0-13.1), respectively. In the over 40 population, the prevalence of myopia and hyperopia was 32.5% (95% confidence interval: 28.9-36.1) and 27.9% (95% confidence interval: 24.5-31.3), respectively. In the multiple regression model for this group, myopia strongly correlated with cataract (odds ratio = 1.98 and 95% confidence interval: 1.33-2.93), and hyperopia only correlated with age (P < 0.001). The prevalence of high myopia and high hyperopia was 1.5% and 4.6%. In the multiple regression model, anisometropia significantly correlated with age (odds ratio = 1.04) and cataract (odds ratio = 5.2) (P < 0.001).

CONCLUSION

The prevalence of myopia and anisometropia was higher than that in previous studies in urban population of Iran, especially in the elderly. Cataract was the only variable that correlated with myopia and anisometropia.

High prevalence of myopia in an adult population, Shahroud, Iran

PURPOSE

To determine the prevalence of myopia and hyperopia and the associated risk factors in the presbyopic age group of the population in Shahroud, Iran.

METHODS

Through a multistage random cluster sampling approach, 6311 people of the 40- to 64-year-old population residing in Shahroud were invited to this study. The prevalence of a cycloplegic spherical equivalent (SE) ≥-0.5 diopter (D) and hyperopia >+0.50 D was determined by age and gender.

RESULTS

Of the invitees, 5190 (82.2%) participated in the study and data from 4864 people was used in the analyses. On the basis of cycloplegic refraction, the prevalence of myopia and hyperopia was 30.2% [95% confidence interval (CI): 28.9 to 31.5] and 35.6 (95% CI: 34.1 to 37.1), respectively. In the multiple logistic regression model, the odds of myopia significantly increased with higher education [odds ratio (OR) = 1.02, p < 0.001] and nuclear cataract (OR = 3.23, p < 0.001). After the age of 54 years, the odds of hyperopia significantly increased compared with the 40- to 44-year age group, whereas higher education and nuclear cataract had negative association with hyperopia. The prevalence of high myopia (SE >-6.0 D) and high hyperopia (SE > 4.0 D) was 1.9% (95% CI: 1.5 to 2.3) and 1.1% (95% CI: 0.8 to 1.4), respectively. Nuclear cataract significantly correlated with high myopia (OR = 6.44) and older age significantly correlated with high hyperopia (OR = 1.12).

CONCLUSIONS

The prevalence of myopia was unexpectedly higher than that found in other parts of the Middle East. The prevalence of hyperopia was lower than that previously reported in Iran. Education correlated directly with myopia and inversely with hyperopia; however, nuclear cataract was the most important risk factor for myopia. Adjusted for other variables, the prevalence of hyperopia still increased with age.

Association of education and occupation with myopia in COMET parents

PURPOSE

To investigate refractive error, especially myopia, in parents of myopic children and its association with education and occupation.

METHODS

Six hundred twenty-seven parents (n = 375 mothers and 252 fathers) of the 469 myopic 6- to <12-year-old children enrolled in COMET provided refraction data as well as answered questions about their education and occupation. Eighty-five percent of the refractions were obtained by non-cycloplegic autorefraction (Nidek ARK 700A), and 15% were obtained from the most recent prescription.

RESULTS

The mean age ± SD of the parents was 44.26 ± 5.81 years, and their mean spherical equivalent refraction was -2.34 ± 2.94 D. Parents with higher education (college degree or greater) had significantly more myopia (-2.97 ± 2.98 D) than parents with lower education (-1.72 ± 2.76 D). The odds of being myopic were significantly higher in the higher education group (multivariate odds ratio = 2.12, 95% confidence interval = 1.41 to 3.19). Mean myopia also differed significantly by occupation, with parents in white collar jobs (-2.87 ± 3.10 D) significantly more myopic than those in blue collar jobs (-1.21 ± 2.02 D) by 1.66 D (p < 0.001). The odds of being myopic between the two occupation groups were of borderline significance (multivariate odds ratio = 1.61, 95% confidence interval = 0.999 to 2.60).

CONCLUSIONS

The parents of myopic children participating in a clinical trial of lenses to slow the progression of myopia had a high prevalence of myopia that was associated with their level of education and to a lesser extent with their choice of occupation. To our knowledge, this is the first account of refractive errors, education, and occupation in parents of a large group of myopic children.

Causes of blindness and visual impairment in Latin America

We review what is known in each country of the Latin American region with regards to blindness and visual impairment and make some comparisons to Hispanic populations in the United States. Prevalence of blindness varied from 1.1% in Argentina to 4.1% in Guatemala in people 50 years of age and older, with the major cause being cataract. Diabetic retinopathy and glaucoma are starting to make serious inroads, although epidemiological data are limited, and age-related macular degeneration is now a concern in some populations. Infectious diseases such as trachoma and onchocerciasis are quickly diminishing. Although progress has been made, retinopathy of prematurity remains the major cause of childhood blindness. If VISION 2020 is to succeed, many more epidemiological studies will be needed to set priorities, although some can be of the Rapid Assessment of Avoidable Blindness design. Developing the infrastructure for screening and treatment of ophthalmic disease in Latin America continues to be a challenge.

Prevalence of the refractive errors by age and gender: the Mashhad eye study of Iran

BACKGROUND

Refractive errors are a common eye problem. Considering the low number of population-based studies in Iran in this regard, we decided to determine the prevalence rates of myopia and hyperopia in a population in Mashhad, Iran.

DESIGN

Cross-sectional population-based study.

PARTICIPANTS

Random cluster sampling. Of 4453 selected individuals from the urban population of Mashhad, 70.4% participated.

METHODS

Refractive error was determined using manifest (age > 15 years) and cycloplegic refraction (age ≤ 15 years). Myopia was defined as a spherical equivalent of -0.5 diopter or worse. An spherical equivalent of +0.5 diopter or worse for non-cycloplegic refraction and an spherical equivalent of +2 diopter or worse for cycloplegic refraction was used to define hyperopia.

MAIN OUTCOME MEASURES

Prevalence of refractive errors.

RESULTS

The prevalence of myopia and hyperopia in individuals ≤ 15 years old was 3.64% (95% CI: 2.19-5.09) and 27.4% (95% CI: 23.72-31.09), respectively. The same measurements for subjects > 15 years of age was 22.36% (95% CI: 20.06-24.66) and 34.21% (95% CI: 31.57-36.85), respectively. Myopia was found to increase with age in individuals ≤ 15 years and decrease with age in individuals > 15 years of age. The rate of hyperopia showed a significant increase with age in individuals > 15 years. The prevalence of astigmatism was 25.64% (95% CI: 23.76-27.51).

CONCLUSIONS

In children and the elderly, hyperopia is the most prevalent refractive error. After hyperopia, astigmatism is also of importance in older ages. Age is the most important demographic factor associated with different types of refractive errors.

Age of first distance spectacle prescription for manifest hyperopia

PURPOSE

This study explores the natural history of hyperopic refractive error in relation to the recalled age of first distance prescription.

METHODS

A population of adult office workers, coming for a general health check-up without refractive selection, completed a questionnaire about age of first distance prescription and were refracted by an ophthalmologist with non-cycloplegic subjective procedures. Hyperopia was defined as a spherical equivalent of +0.75 diopters or more. This study included 145 hyperopes aged 50-65 years at interview.

RESULTS

The hyperopic subjects were first prescribed spectacles for distance vision in a broad spectrum of ages, from early childhood to adulthood. The subjects with older ages of first prescription tended to develop lower amounts of refractive error but this relation was not significant (Spearman's rho -0.126, p = 0.131).

CONCLUSIONS

The age of first spectacle prescription in hyperopes is not strongly related to the final refractive error developed in adulthood.

Refractive error among the elderly in rural Southern Harbin, China

PURPOSE

To estimate the prevalence and associated factors of refractive errors among the elderly in a rural area of Southern Harbin, China.

METHODS

Five thousand and fifty seven subjects (age > or = 50 years) were enumerated for a population-based study. All participants underwent complete ophthalmic evaluation. Refraction was performed by ophthalmic personnel trained in the study procedures. Myopia was defined as spherical equivalent worse than -0.50 diopters (D) and hyperopia as spherical equivalent worse than +0.50 D. Astigmatism was defined as a cylindrical error worse than 0.75D. Association of refractive errors with age, sex, and education were analyzed.

RESULTS

Of the 5,057 responders (91.0%), 4,979 were eligible. The mean age was 60.5 (range 50-96) years old. The prevalence of myopia was 9.5% (95% confidence interval [CI], 8.5-10.1) and of hyperopia was 8.9% (95% CI, 7.9-9.5). Astigmatism was evident in 7.6% of the subjects. Myopia, hyperopia and astigmatism increased with increasing age (p<0.001, respectively). Myopia and astigmatism were more common in males, whereas hyperopia was more common in females. We also found that prevalence of refractive error weas associated with education. Myopia was more common in those with higher degrees of education, whereas hyperopia and astigmatism were more common in those with no formal education.

CONCLUSIONS

This report has provided details of the refractive status in a rural population of Harbin. The prevalence of refractive errors in this population is lower than those reported in other regions of the world.