Prevalence and causes of visual impairment and rate of wearing spectacles in schools for children of migrant workers in Shanghai, China

Prevalence and Pattern of Eye Disorders Among Primary Schoolchildren in Abakaliki, Nigeria: A Cross-Sectional Study

Background A child's learning ability depends on vision, and visual impairment negatively affects neurological, intellectual, and emotional development by limiting children's exposure to a range of experiences and information. This study aims to determine the prevalence and pattern of ocular morbidity among primary schoolchildren in Abakaliki and provide evidence that can be used in planning a school eye health program for the state. Methodology A school-based, cross-sectional study was conducted within the Abakaliki metropolis between January and April 2018 to determine the ocular health status of schoolchildren recruited using stratified random sampling. Data were analyzed using SPSS version 22 (IBM Corp., Armonk, NY, USA) and presented using descriptive statistics. Univariate analysis was performed to determine the association between dependent and independent variables, with the level of significance determined by a p-value <0.05 (95% confidence interval (CI)). Results A total of 553 schoolchildren aged 6-16 years were examined. The prevalence of eye disorders was 23.5%. Common disorders included refractive error (12.7%) and allergic eye disease (7.1%). Other findings included glaucoma suspect (15, 2.7%), infective conjunctivitis (1, 0.2%), amblyopia (3, 0.5%), cataract (1, 0.2%), and squint (1, 0.2%). The prevalence of visual impairment was 3.1%. Univariate analysis showed a significant association between ocular morbidity and attending private schools (95% CI = 6.5-11.1, p = 0.003). Conclusions Eye disorders such as uncorrected refractive error and allergic conjunctivitis were common among schoolchildren. School eye health programs can ensure that eye screening is done periodically, allowing for early detection, referral, and prompt treatment of eye diseases that can potentially cause visual impairment.

Demographic and Clinical Characteristics of 600 Children With Nystagmus

PURPOSE

To characterize a large, international cohort of children with nystagmus.

METHODS

Data were collected from a single-center, prospectively developed database on patients with nystagmus. Outcome variables for this study included: (1) demographic characteristics, (2) nystagmus type, (3) clinical characteristics, (4) associated ophthalmic conditions, (5) associated non-ophthalmic conditions, (6) special testing findings, and (7) treatments.

RESULTS

Six hundred patients from 38 states and 30 countries were included. Age ranged from birth to younger than 18 years (mean: 15.2 years), 58% were female, 55% were race other than White, 75% had infantile nystagmus syndrome, 17% had neurologically significant nystagmus, 7% had fusion maldevelopment nystagmus syndrome, 64% had strabismus, 56% had an anomalous head posture, 94% had a significant refractive error, 64% had an associated ophthalmic abnormality (excluding ametropia), and 45% had an associated systemic condition. Special testing showed abnormalities in 67% and 95% had treatment directed at their nystagmus.

CONCLUSIONS

The most common diagnosis in this cohort is neurologically non-significant infantile nystagmus syndrome. Eye movement recordings provide a path toward accurate diagnosis and classification. There was a high prevalence of underlying ocular and/or systemic conditions requiring ophthalmic special testing as part of a diagnostic routine. Clinical treatments are available to most patients. [J Pediatr Ophthalmol Strabismus. 2023;60(6):406-410.].

Variations in the prevalence of vision impairment across regions among school children in Telangana State, South India

Purpose

Undetected vision impairment (VI) could negatively affect the overall development in children. School vision screening program is a viable and cost-effective approach for the early identification and management of VI.

Aim

This study aims to estimate the prevalence of VI, its risk factors, and ocular morbidity among school children in Telangana, South India.

Methods

Children aged 4-15 years attending schools in the study area were screened in this study. The vision screenings were performed in schools by trained community eye health workers using 6/12 tumbling E optotypes. Children who failed the test and/or presented with other eye conditions were referred to vision centers or secondary and tertiary eye care centers. A comprehensive eye examination was conducted in these centers, including cycloplegic refraction and fundus examination.

Results

A total of 774,184 children, with a mean age of 9.4 ± 3.27 years, were screened. Overall, 51.49% (N = 398,596) were male. In total, 4.33% [N = 33,528; 95% confidence interval (CI): 4.29-4.38] required referral services, while 1.16% (N = 9,002) had a presenting visual acuity of < 6/12. Multivariate analysis showed a high risk of VI among older children [Adj. odds ratio (OR): 5.75; 95% CI: 5.18-6.38], those with disabilities (Adj. OR: 5.12; 95% CI: 4.14-6.33), female gender (Adj. OR: 1.29; 95% CI: 1.24 - 1.35), and those residing in the urban areas (Adj. OR: 2.87; 95% CI: 2.42-3.39). The main cause of VI was uncorrected refractive errors (74.14%).

Conclusion

The prevalence of VI among school children was 1.16% in Telangana, South India, and refractive error was the leading cause of VI among this population. Increasing age, urban location, female gender and other disabilities increase the risk of VI among children.

Gender differences in horizontal strabismus: Systematic review and meta-analysis shows no difference in prevalence, but gender bias towards females in the clinic

Background

Strabismus is a misalignment of the visual axis that affects 2-3% of the population and can lead to loss of binocular vision. It is currently controversial whether there is a gender difference in the most common form of visual misalignment: horizontal strabismus. Some studies claimed that more females than males have an outward deviation (exotropia), while others concluded that there is no significant gender difference. No previous work has systematically explored gender differences in horizontal strabismus or has compared the results of population-based studies with those of clinic-based studies.

Methods

We conducted a systematic review and meta-analysis of studies reporting the prevalence of horizontal strabismus. We included 73 population-based studies and compared their disclosed gender population with that in 141 comparable clinical-based studies. We analysed the data according to gender, strabismus type (esotropia, exotropia), and geographic region/ethnicity.

Results

Summary statistics showed a nearly identical prevalence of horizontal strabismus (2.558% for males, 2.582% for females), esotropia (1.386% males vs. 1.377% females), and of exotropia (1.035% males vs. 1.043% females). Meta-analysis results showed that these differences between males and females were not statistically significant (odds ratio (OR) = 1.01; 95% confidence interval (CI) = 0.97-1.10), but that females were significantly more frequent (by 7.50%) in clinic-based studies than males, with 5.00% more females for esotropia, and 12.20% more females for exotropia when adjusted for the population's sex ratio. The extent of the female gender bias differed between geographic regions/societies, with Asians having the lowest bias towards females and Latin American countries having the strongest bias.

Conclusions

Males and females have the same prevalence of horizontal strabismus, including exotropia. Females with strabismus seek health care or are brought to clinics significantly more often than males. This is an example of gender bias in health care in favour of females rather than males, apparently because parents - erroneously fearing only cosmetic consequences - are more concerned about strabismus in their daughters than their sons. Societal attitudes towards females, as well as economic factors (insurance status), appear to be relevant factors that determine the magnitude of the gender bias in horizontal strabismus.

Improving eye care quality through brief verbal intervention on optometry service provider by using unannounced standardized patient with refractive error: study protocol for a randomized controlled trial

BACKGROUND

Improper refractive correction can be harmful to eye health, aggravating the burden of vision impairment. During most optometry clinical consultations, practitioner-patient interactions play a key role. Maybe it is feasible for patients themselves to do something to get high-quality optometry. But the present empirical research on the quality improvement of eye care needs to be strengthened. The study aims to test the effect of the brief verbal intervention (BVI) through patients on the quality of optometry service.

METHODS

This study will take unannounced standardized patient (USP) with refractive error as the core research tool, both in measurement and intervention. The USP case and the checklist will be developed through a standard protocol and assessed for validity and reliability before its full use. USP will be trained to provide standardized responses during optical visits and receive baseline refraction by the skilled study optometrist who will be recruited within each site. A multi-arm parallel-group randomized trial will be used, with one common control and three intervention groups. The study will be performed in four cities, Guangzhou and three cities in Inner Mongolia, China. A total of 480 optometry service providers (OSPs) will be stratified and randomly selected and divided into four groups. The common control group will receive USP usual visits (without intervention), and three intervention groups will separately receive USP visits with three kinds of BVI on the patient side. A detailed outcome evaluation will include the optometry accuracy, optometry process, patient satisfaction, cost information and service time. Descriptive analysis will be performed for the survey results, and the difference in outcomes between interventions and control providers will be compared and statistically tested using generalized linear models (GLMs).

DISCUSSION

This research will help policymakers understand the current situation and influencing factors of refractive error care quality, and then implement precise policies; at the same time, explore short and easy interventions for patients to improve the quality of optometry service.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200062819. Registered on August 19, 2022.

Refractive Errors and Their Associated Factors in Schoolchildren: A Structural Equation Modeling

PURPOSE

To determine the prevalence of myopia and hyperopia in Shahroud schoolchildren and their risk factors.

METHODS

Optometric examinations including the measurement of uncorrected and corrected visual acuity as well as non-cycloplegic and cycloplegic refraction using retinoscopy were done for students. Generalized Structural Equation Modeling (GSEM) was used to determine direct and indirect effects of independent variables on myopia and hyperopia.

RESULTS

The data of 5581 students with a mean age of 9.24 ± 1.7 years were used in this study. The prevalence of myopia was 5.0% (95%CI: 4.3-5.7) and the prevalence of hyperopia was 4.8% (95%CI: 4.0 - 5.5) in all schoolchildren. According to the GSEM results, the odds of myopia in rural areas were 0.55 compared to urban areas. A one-unit increase in the ocular AL increased the odds of myopia by 4.91 times. The interaction of sex and age on myopia was significant such that in girls, the odds of myopia increased by 20% for every one-year increase in age while no significant change was seen in boys. A one-unit increase in the ocular AL decreased the odds of hyperopia by 0.49 times. Moreover, the interaction of outdoor activity hours and sex on the prevalence of hyperopia was significant such that increased outdoor activity reduced the odds of hyperopia in girls while no significant correlation was found in boys.

CONCLUSION

Myopia and hyperopia had moderate prevalence. Axial Length had the largest direct association on myopia and hyperopia. Age and outdoor activity had weak associations on refractive errors.

The prevalence and causes of pediatric uncorrected refractive error: Pooled data from population studies for Global Burden of Disease (GBD) sub-regions

BACKGROUND

There are limited systematic reviews on the prevalence of uncorrected refractive errors in children. We aimed to summarize the prevalence and causes of pediatric uncorrected refractive error (URE) from studies in the Global Burden of Disease (GBD) sub-regions.

METHODS

The pooled analysis used the individual participant data (ages less than 20 years old) from population-based studies around the world by regions. URE was defined as presenting VA < 6/18 and improving to ≥ 6/18 or ≥1 line on using a pinhole in either eye, with main causes of myopia, hyperopia or astigmatism. Each study provided data on any URE, myopia, hyperopia or astigmatism by age, gender, and ethnicity. Prevalence rates were directly age and gender standardized to the 2020 world population with all age groups. Estimates were calculated by study and sub-regions after pooling. Summary estimates included studies in which URE was assessed from a pinhole-corrected refraction in the better eye.

RESULTS

The combined pooled data contained 302,513,219 patients including 8 963 URE cases individuals from 57 studies. Prevalence varied by age and GBD sub-regions and differed by gender. The age- and region-standardized prevalence of URE was 3.41 per 1000 (CI, 1.53~7.62) in Western Pacific region (12 studies), 2.26 per 1000 (CI, 0.85~6.01) in South-East Asia region (14 studies), 5.85 per 1000 (CI, 3.75~9.13) in Americans (11 studies) and 4.40 per 1000 (CI, 3.0~6.45) in Eastern Mediterranean region (13 studies). On the basis of these data, myopia was the first-leading cause in female children with 12~17 age group, with the prevalence rate 18.2 per 1000 (CI, 11.52~23.61). Astigmatism was detected in 27.2 per 1000 male children with 6~11 age group (CI: 19.12-30.68).

CONCLUSIONS

Prevalence of URE available data within these sub-regions are widely disparate. Myopia and astigmatism in young age children continue as the leading cause of URE worldwide. Providing appropriate refractive correction to those individuals whose vision can be improved is an important public health endeavor with implications for safety and quality of life.

Visual impairment and refractive errors in school children in Andhra Pradesh, India

Purpose

Addressing childhood vision impairment (VI) is one of the main goals of the World Health Organization's (WHO) combating blindness strategies. The primary aim of this study was to estimate the prevalence of VI, causes, and its risk factors in school children in Krishna district, Andhra Pradesh, India.

Methods

Children aged 4-15 years were screened in schools using the 6/12 Snellen optotype by trained community eye health workers, and those who failed the test and those reported or found to have obvious eye conditions were referred to primary (VC), secondary (SC), or tertiary (TC) care centre appropriately, where they underwent a complete eye examination including cycloplegic refraction and fundus examination.

Results

A total of 56,988 children were screened, of whom 51.18% were boys. The mean age was 9.69 ± 3.26 years (4-15 years). Overall, 2,802/56,988 (4.92%) children were referred to a VC, of which 632/56,988 (1.11%) required referral to SC/TC. PVA of <6/12 was found in 1.72% (95% confidence interval [CI]: 1.61-1.83). The prevalence of refractive error (corrected and uncorrected) was 2.38% (95% CI: 2.26-2.51) and myopia was 2.17% (95% CI: 2.05-2.29). In multivariable analysis, older children, those in urban schools, private schools, and children with a disability had an increased risk of VI and myopia. Additionally, the risk of myopia was higher among girls than boys. Of those referred and reached SC/TC, 73.64% were due to avoidable causes.

Conclusion

Childhood VI prevalence was 1.72% in this region. Uncorrected refractive error (URE) was the major cause of VI in children. Older age, schools in urban locations, private schools, and the presence of disability were associated with the risk of VI among children.

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.

Global Prevalence and Causes of Visual Impairment and Blindness in Children: A Systematic Review and Meta-Analysis

Purpose:

To determine the global prevalence and common causes of visual impairment (VI) and blindness in children.

Methods:

In this meta-analysis, a structured search strategy was applied to search electronic databases including PubMed, Scopus, and Web of Science, as well as the list of references in the selected articles to identify all population-based cross-sectional studies that concerned the prevalence of VI and blindness in populations under 20 years of age up to January 2018, regardless of the publication date and language, gender, region of residence, or race. VI was reported based on presenting visual acuity (PVA), uncorrected visual acuity (UCVA), and best corrected visual acuity (BCVA) of equal to 20/60 or worse in the better eye. Blindness was reported as visual acuity worse than 20/400 in the better eye.

Results:

In the present study, 5711 articles were identified, and the final analyses were done on 80 articles including 769,720 people from twenty-eight different countries. The prevalence of VI based on UCVA was 7.26% (95% confidence interval [CI]: 4.34%–10.19%), PVA was 3.82% (95% CI: 2.06%–5.57%), BCVA was 1.67% (95% CI 0.97%–2.37%), and blindness was 0.17% (95% CI: 0.13%–0.21%). Refractive errors were the most common cause of VI in the subjects of selected articles (77.20% [95% CI: 73.40%–81.00%]). The prevalence of amblyopia was 7.60% (95% CI: 05.60%–09.10%) and congenital cataract was 0.60% (95% CI: 0.3%–0.9%).

Conclusion:

Despite differences in the definition of VI and blindness, based on PVA, 3.82%, and based on BCVA, 1.67% of the examined samples suffer from VI.

Spectacle design preferences among school children in Enugu State, Nigeria

Background

Uncorrected refractive error has profound effects on children's educational and social development and spectacles are cost-effective in correcting this. However, the cosmetic appearance of spectacles may affect compliance to prescribed spectacles.

Aims

This study explored spectacle design preferences of school children in Enugu State, Nigeria and any associated sociodemographic factors. A cross-sectional study among children aged 5-15 years from schools in Enugu state, Nigeria.

Patients and Methods

The children independently selected from sets of spectacle frames, indicating their preferences on the basis of spectacle frame color, material, shape and size of the lens portion, design of the earpiece portions. Simple descriptive analysis was performed. Frequency tables were generated. Pearson's Chi-square test was used to test associations between categorical variables. Odds ratios were used to measure the strength of the associations where P < 0.05. Tests of significance were set at the 95% level.

Results

A total of 1,167 children (45.6% male and 54.4% female) were seen. Majority of the children preferred red colored spectacle frames 467 (40%), plastic frames 723 (62%), rectangular shaped lens-pieces (55.2%), and frames with a straight earpiece 987 (84.6%). There is a strong association between gender and choice of spectacle colour (P < 0.01), gender and lens size preference (P < 0.05), and between school location and shapes of spectacle earpiece (P < 0.01).

Conclusions

Spectacle preferences exist among the study population and some demographic factors are associated with these preferences which should be considered in any childhood refractive error services.

Development of deep learning-based detecting systems for pathologic myopia using retinal fundus images

Globally, cases of myopia have reached epidemic levels. High myopia and pathological myopia (PM) are the leading cause of visual impairment and blindness in China, demanding a large volume of myopia screening tasks to control the rapid growing myopic prevalence. It is desirable to develop the automatically intelligent system to facilitate these time- and labor- consuming tasks. In this study, we designed a series of deep learning systems to detect PM and myopic macular lesions according to a recent international photographic classification system (META-PM) classification based on color fundus images. Notably, our systems recorded robust performance both in the test and external validation dataset. The performance was comparable to the general ophthalmologist and retinal specialist. With the extensive adoption of this technology, effective mass screening for myopic population will become feasible on a national scale.

Lu et al. develop a deep-learning based detection system for identifying pathological myopia and myopic macular legions in retinal fundus images. The system performance is comparable to human experts, but much faster, easing the burden of human time on screening for myopia.

Evaluation of health appraisal project of primary school children: a study in Egypt

BACKGROUND

School Health insurance (SHI) is working in Egypt since 2003. However, there were no impact indicators that inform policy makers about health status of school children. Therefore, the school health project was conducted by Arab Medical Union (AMU) Medical Syndicate in cooperation with Ministry of Education (MOE), Ministry of Health and Population (MOHP) and Public Health Department, Cairo University to conduct comprehensive medical services to primary school children and to assess the impact of the SHI and the efficiency of AMU project to promote health of children.

METHODS

In-depth interview with policy makers in MOHP, MOE, SHI and secondary analysis of AMU documents. A systematic random sample of 7000 students (7-10 years) was selected which formed 10% of the examined children in AMU project and proportionally distributed in 355 schools in seven Districts in Fayoum Governorate.

RESULTS

SHI was ineffective in providing preventive services to school children. The AMU project was efficient in covering 82% of the targeted students with clinical, preventive and referral services with estimated cost per student were 54.8LE. Clinical findings showed anaemia the major problem (84%), dental (33%), hair/scalp (9%) and visual errors (6%).

CONCLUSION

The current Primary Health Care facilities needs to improve the quality preventive and curative health services provided to school children. Also, providing health services through medical conveys was of high cost and unsustainable.

Frequency of presenting visual acuity and visual impairment in Chinese college students

AIM

To obtain the baseline data on presenting visual acuity (PVA) and evaluate the prevalence and associated factors for visual impairment based on PVA in 9070 Chinese college students.

METHODS

The freshmen at a university in southern China, including 6527 undergraduate students and 2543 graduate students, were investigated for some socio-demographic characteristics and underwent routine medical examination, including measuring PVA, height, and weight. Visual impairment was defined according to the new World Health Organization criteria for blindness and visual impairment.

RESULTS

In 9070 college students, the mean PVA in the better eye was 0.094±0.163 logMAR. The prevalence of visual impairment based on PVA was 2.7%. Only 38.3% college students had normal visual acuity [PVA equal to 0 logMAR (20/20) in both eyes]. There were 69.8% of students wearing spectacles. Logistic regression showed that home region (non-Guangdong provinces, P<0.0001, OR=1.70) was risk factor for visual impairment while BMI (P=0.001, OR=0.92) was protective factor from visual impairment. Ethnicity (Han Chinese, P<0.0001, OR=3.17) was risk factor for wearing spectacles while age (P=0.01, OR=0.90) was protective factor from wearing spectacles.

CONCLUSION

This study provides the baseline data on PVA and the prevalence of visual impairment in Chinese college students. Our analyses reveal that BMI and home region are associated factors for visual impairment based on PVA, while age and ethnicity are associated factors for wearing spectacles.

The Prevalence of Ptosis and Nystagmus in Rural Population

Purpose

To determine the prevalence of ptosis and nystagmus in the general rural population in Iran.

Methods

Two villages were selected from the north and southwest of Iran using a multi-stage cluster sampling approach. After selection of the participants and inviting them to a complete eye exam, they all had vision tests and an ophthalmic examination. Vision tests included measurement of visual acuity, refraction, and the cover test. Then the slit-lamp exam was performed, and the diagnosis of ptosis and nystagmus was determined by an ophthalmologist.

Results

Of the 3851 invitees, 3314 people participated in the study. The prevalence of ptosis in this study was 2.23% [95% confidence interval (CI): 1.73-2.74], and 45.3% of the cases were bilateral ptosis. The prevalence of ptosis was lowest in the 21-30 year (0.2%) and the under 5 year (0.8%) age groups, and the highest prevalence was observed in people over 70 years of age (6.7%) (P < 0.001). The prevalence of ptosis was higher in illiterate people than those with an academic education level (P = 0.012). The prevalence of astigmatism was 62.8% in those with ptosis and 34.2% in those without ptosis (P < 0.001). The prevalence of nystagmus was 0.39% (13 cases).

Conclusions

This study found that the prevalence of ptosis is relatively high in the general rural population in Iran, and the prevalence increases with age. Astigmatism is significantly high among cases with ptosis, and its prevalence has an inverse relation with the level of education. Nystagmus also had a high prevalence in this population.

Using incognito standardised patients to evaluate quality of eye care in China

Background/aims

Few studies have objectively examined the quality of eye care in China. We assessed refractive care using the incognito standardised patient (SP) approach, a gold standard for evaluating clinical practice.

Methods

A total of 52 SPs were trained to provide standardised responses during eye examinations, and underwent automated and non-cycloplegic, subjective refraction by a senior ophthalmologist from Zhongshan Ophthalmologic Center, a national-level clinical and research centre. SPs subsequently received subjective refraction and eye exams at a randomly selected sample of 40 public hospitals and 93 private optical shops in Shaanxi, Northwestern China. Difference between expert and local refraction in the better-seeing eye was calculated by the vector diopteric method, and completeness of exams assessed against national standards. SP and provider demographic information and provider clinical experience were recorded.

Results

SPs (n=52, mean (range) age, 25.7 (22–31) years, 28.8% male) underwent 133 eye exams (mean total duration 15.0±11.7 min) by 133 local refractionists (24–60 years, 30.3% male). Only 93 (69.9%), 121 (91.0%) and 104 (78.2%) of local refractionists assessed vision, automated and subjective refraction, respectively. The median inaccuracy was −0.25 diopters (D), while 25.6% of results differed by an absolute value of ≥1.0 D and 6.0% by ≥2.0 D. Predictors of inaccurate refraction included spectacle power <−6.0 D (OR=2.66; 95% CI, 1.27 to 5.56), service at a public (vs private) hospital (OR=2.01; 95% CI, 1.11 to 3.63) and provider male sex (OR=2.03; 95% CI, 1.11 to 3.69).

Conclusion

Inaccurate refractions are common in Northwestern China, particularly in public facilities. Important assessments, including subjective refraction, are frequently omitted.

A Serial Cross-Sectional Analysis of the Prevalence, Risk Factors and Geographic Variations of Reduced Visual Acuity in Primary and Secondary Students from 2000 to 2017 in Hong Kong

Background: We would like to investigate the prevalence trend, potential risk factors and geographic features of reduced visual acuity (VA) in primary and secondary schoolchildren of Hong Kong. Methods: This was a serial cross-sectional study using historical data of schoolchildren aged 6 to 15 years from the annual health checks conducted at Student Health Service Centers across Hong Kong, for the school years of 2000/2001 to 2016/2017. Results: The prevalence of reduced VA increased from 49.23% (95% CI, 48.99-49.47) in 2000/2001 to 54.34% (95% CI, 54.10-54.58) in 2011/2012 but decreased to 51.42% (95% CI, 51.17-51.66) in 2016/2017. Girls were less susceptible than boys at age 6-7 (and in grade primary 1-2), but more susceptible at older ages. The prevalence in junior grades increased while the risk effect of grade reduced over the past 17 years. Geographic variation on the risk for reduced VA existed and spatial autocorrelation was positive. The difference in prevalence of reduced VA between Hong Kong and mainland China has decreased in recent years. Cross-border students living in mainland China were associated with a lower risk for reduced VA. Conclusions: Further study was proposed to investigate the environmental association between students living in and outside Hong Kong with the prevalence of reduced VA. Multi-level research should also be conducted to investigate the influence of compositional and contextual factors on the prevalence of reduced VA.

Global prevalence of amblyopia and disease burden projections through 2040: a systematic review and meta-analysis

Purpose

Amblyopia is a leading cause of vision impairment among children and young adults. Individual studies showed significant variations in the prevalence of amblyopia in different regions and age groups. This study is to estimate the global prevalence of amblyopia by pooling its prevalence from the previous studies and to project the number of people affected through 2040.

Methods

We performed a systematic review and meta-analysis on the prevalence of amblyopia using data published before 20 October 2018. We estimated the prevalence rate of amblyopia and its 95% CI globally and by subgroups (eg, region and age). The prevalence data were applied to United Nations World Population Prospects to derive the projected number with amblyopia through 2040.

Results

A meta-analysis of 60 studies (1 859 327 subjects) showed that the pooled prevalence rate of amblyopia was 1.44% (95% CI 1.17% to 1.78%). Prevalences in Europe (2.90%) and North America (2.41%) were higher than in Asia (1.09%) and Africa (0.72%). The highest prevalence was found in subjects over 20 years old (3.29%). There was no difference in the prevalence between genders. We estimated 99.2 (95% CI 71.7 to 146.1) million people with amblyopia in 2019 worldwide, increasing to 175.2 (95% CI 81.3 to 307.8) million by 2030 and 221.9 (95% CI 83.7 to 429.2) million by 2040.

Conclusions

The amblyopia is becoming a significant vision problem worldwide. It is of great importance to design and implement amblyopia screening, treatment and related public health strategies.

Visual Impairment and Spectacle Use in University Students in Central China: The Anyang University Students Eye Study

PURPOSE

To investigate the prevalence and associations of visual impairment and spectacle use in university students in central China.

DESIGN

Cross-sectional study.

METHODS

This study included students aged 16-26 years in China. Study subjects from 2 universities underwent distance visual acuity (VA) assessment in both eyes with a logarithm of the minimum angle of resolution chart and their refractions were measured by cycloplegic autorefraction. Blindness was defined as presenting VA less than three-sixtieth in the better eye (World Health Organization definition), and visual impairment was defined as presenting VA less than six-twelfths.

RESULTS

Overall, 9710 undergraduates were enumerated, 7704 (79.3%) subjects were included in this study. The prevalence of uncorrected VA less than six-twelfths and less than three-sixtieth in the better eye were 69.9% and 0.9%, respectively. Only 77.0% (4148/5388) of subjects with uncorrected VA in the better eye of less than six-twelfths wore glasses. For presenting VA, the prevalence of mild (VA <6/12 to 6/18), moderate (VA <6/18 to 6/60), and severe (VA <6/60 to 3/60) visual impairment was 6.3%, 11.2%, and 0.7%, respectively. Overall, 71.7% (4300/6001) of students with myopia (spherical equivalent ≤-0.5 diopters) wore spectacles. In multiple logistic regression analysis, visual impairment was associated with female sex (P < .001) and lower year level of education (P = .006) when presenting with VA.

CONCLUSIONS

This study has documented a relatively high prevalence of visual impairment and relatively low spectacle coverage in Chinese university students. Given the potential impact of visual impairment, target education and accessible refraction services are highly important to solve the problem.

Socio-economic status, visual impairment and the mediating role of lifestyles in developed rural areas of China

PURPOSE

To examine the impacts of socio-economic status (SES) on visual impairment (VI), and the mediating role of lifestyles in developed rural areas of China.

METHODS

A cross-sectional study was conducted among people living in rural districts of Tianjin, a developed municipality in China. An interviewer-administered survey along with free eye screenings was conducted with participants. The questionnaire included questions about demographic characteristics, SES, medical histories and lifestyles. Presenting visual acuity (PVA) and main causes of VI were identified by ophthalmologists. χ2 test was undertaken to determine whether significant differences (p<0.05) exist between VI and demographic, SES, medical history and lifestyle factors. A stepwise regression method was conducted to investigate whether lifestyles play mediating roles between SES and VI. Multivariable logistic and ordinal logistic regression were used contingent on different types of dependent variables in each regression, and adjusted odds ratio (OR) values were estimated.

RESULTS

Of the 12,233 participants, 6,233 were male (50.59%); the mean age was 34.61 years; 310 (2.54%) had VI. Hypertension, diabetes and cardiopathy were main medical histories, with 1,640 had hypertension (13.41%), 854 had diabetes (6.98%) and 483 had cardiopathy (3.95%). About SES factors, higher education level (Adjusted OR, 0.84; 95% CI, 0.75-0.95) and higher income level (Adjusted OR, 0.54; 95% CI, 0.39-0.76), were significantly associated with VI in a gradient across severity of VI. Lifestyles including smoking (Adjusted OR, 1.55; 95% CI, 1.31-1.83) and drinking (Adjusted OR, 1.36; 95% CI, 1.06-1.74) played mediating roles between SES and VI when considering the full sample. Besides smoking and drinking, reading every week (Adjusted OR, 2.07; 95% CI, 1.53-2.82) and exercising more than 2h every day (Adjusted OR, 0.39; 95% CI, 0.15-1.00) also played mediating roles between SES and VI when considering the subsample (age≥16).

CONCLUSION

This study revealed the crucial impacts of SES factors on VI, and the mediating role played by several lifestyles. Targeted public health interventions for reducing VI should thus be proposed in developed rural areas of China.

The prevalence of vision impairment and refractive error in 3654 first year students at Tianjin Medical University

AIM

To determine the prevalence of vision impairment (VI) and refractive error in first year university students at the Tianjin Medical University.

METHODS

This is a cross-sectional observational cohort study of VI and refractive error among first year university students at the Tianjin Medical University. The first year university students were involved in this study and were given a detailed questionnaire including age, birth date, and spectacle wearing history. A standardized ophthalmologic examination including visual acuity (VA), slit-lamp examination, non-cycloplegic auto-refraction, objective refraction, fundus photography, and examination of their spectacles were recorded.

RESULTS

A total of 3654 participants were included in this study. Totally 3436 (94.03%) individuals had VI in this population. Totally 150 (4.10%) individuals had VI due to ocular disease, including amblyopia, congenital cataract, retinal atrophy or degeneration, strabismus, congenital nystagmus, refractive surgery orthokeratology. Totally 3286 (89.93%) subjects had VI due to refractive error. Only 218 (5.97%) students were emmetropia. Moreover, refractive error was the main cause for the VI (95.63%). Totally 3242 (92.52%) students were myopia and the prevalence of mild, moderate, and high myopia subgroup was 27.05%, 44.35%, and 21.26% respectively. Totally 44 (1.29%) subjects were hyperopic. The rates of uncorrected visual acuity (UCVA), presenting visual acuity (PVA) and best corrected visual acuity (BCVA) which better than 20/20 in both eyes were 5.65%, 22.32% and 82.13% respectively. The rates of correction, under correction and well correction in myopia subjects were 82.73%, 84.39% and 15.61%, respectively.

CONCLUSION

We present a high prevalence of refractive errors and high rates of under correction refractive error among first year university students. These results may help to promote vision protection work in young adults.

Spectacles utilization and its impact on health-related quality of life among rural Chinese adolescents

PURPOSE

The aims of the study were to assess the magnitude and predictors of the unmet need for spectacles utilization and to quantify its impact on health-related quality of life (HRQOL) among rural Chinese adolescents.

METHODS

This school-based survey of 2346 grade-7 students (mean age: 13.8 years) was conducted in Southwestern China in 2016. Spectacles need was defined as uncorrected visual acuity (VA) of 20/40 or worse but correctable to 20/40 or better in the better-seeing eye, together with the presence of myopia of less than -0.5 diopters (D), hyperopia of more than +2.0 D, or astigmatism of more than 0.75 D in both eyes. The HRQOL was measured using self-reported versions of 23-item Pediatric Quality of Life Inventory Version 4.0 Generic Core Scales (PedsQL 4.0).

RESULTS

Among 579 (24.7%) adolescents with an uncorrected VA of 20/40 or less, 483 (83.4%) needed vision corrections and 172 (35.6%) used them. Higher parental education levels (odds ratio (OR) = 2.73; 95% CI, 1.29-5.77), negative attitude regarding spectacles (OR = 0.49; 95% CI, 0.25-0.97), and poorer uncorrected VA (OR = 31.27; 95% CI, 3.76-260.23) were independent determinants for spectacles utilization. Adolescents not using spectacles had a lower HRQOL score compared to those using spectacles in terms of psychosocial health (65.91 vs. 70.59; P = 0.028), emotional health (56.85 vs. 63.24; P = 0.012), and social functioning (72.99 vs. 78.60; P = 0.036).

CONCLUSIONS

The rate of spectacles utilization in rural China was low. Adolescents were not accustomed to use spectacles had a worse HRQOL score.

Prevalence of reduced visual acuity among preschool children in eastern China and comparison at a 5-year interval

IMPORTANCE

Assessing the prevalence of reduced visual acuity and its change over time has significant public health importance. This study evaluated prevalence of reduce visual acuity in children aged 48-60 months, and compared it with previous data.

BACKGROUND

Previous studies reported prevalence of reduced visual acuity in preschool children, but none has evaluated prevalence change in the same area.

DESIGN

Nanjing Eye Study, a longitudinal population-based study.

PARTICIPANTS

Two thousand three hundred eligible children.

METHODS

Comprehensive eye examinations.

MAIN OUTCOME MEASURES

Uncorrected visual acuity, presenting visual acuity, best-corrected visual acuity, anterior segment and fundus examination, cycloplegic refraction.

RESULTS

Based on the worse and better eye, respectively, 6.8% and 3.5% had reduced uncorrected visual acuity and 4.0% and 1.4% had reduced presenting visual acuity. Compared to rates in the Nanjing Paediatric Vision Project carried out 5 years ago in the same area, the prevalence rates of reduced uncorrected visual acuity were significantly higher (6.8% vs. 5.3%, P = 0.04 for worse eye; 3.5% vs. 2.1%, P = 0.0049 for better eye), but there was no significant increase in rates of reduced presenting visual acuity (4.0% vs. 3.7%, P = 0.63 for better eye; 1.4% vs. 1.7%, P = 0.43 for worse eye). The prevalence rate of glasses prescription is higher in this study (4.5% vs. 3.1%, P = 0.02).

CONCLUSIONS AND RELEVANCE

Prevalence of reduced uncorrected visual acuity increased significantly, indicating that Chinese children are faced with more vision-threatening factors. However, more children with refractive errors got appropriate correction.

Different patterns of myopia prevalence and progression between internal migrant and local resident school children in Shanghai, China: a 2-year cohort study

Background

In 2010, there were ~ 36 million migrant children under 18 y old in China. This study compared patterns of myopia prevalence and progression between migrant and resident children.

Methods

Eight hundred forty-two migrant children from 2 migrant schools and 1081 from 2 local schools in Baoshan District, Shanghai, were randomly chosen. Baseline measurements were taken on children in grades one through four, and children in grades one and two were followed for 2 y. The children underwent comprehensive ophthalmic examinations, including cycloplegic refraction and axial length. The average time per week spent on homework and outdoor activities were investigated.

Results

Migrant children in grades one and two showed a lower myopia prevalence than resident children; however, from grades three to four, the prevalence accelerated and exceeded that of residents. In the follow-up, the myopia incidence did not significantly change from grades one to two in resident children but was significantly higher in grade two in migrant children. Correspondingly, for migrant children, increased progression of refraction and axial length was observed; however, it decreased in resident children. The average time spent on homework increased from grades two to three in parallel with the acceleration of myopia prevalence for migrant children; however, the time spent outdoors did not correspondingly change.

Conclusion

The patterns of myopia prevalence and progression are different between migrant and non-migrant children. The acceleration of myopia in migrant children might be a result of a change in their environment, such as intensive education pressure.

Epidemiology of Reduced Visual Acuity among Chinese Multiethnic Students

SIGNIFICANCE

Data regarding the epidemiology of reduced visual acuity (VA) among multiethnic children and adolescents in China are few. Understanding the vision-related health inequalities among different ethnic groups is crucial for health resource allocations and clinical managements for eye diseases.

PURPOSE

We aim to determine the prevalence, main causes, and health inequalities of reduced VA in multiethnic school students in rural China.

METHODS

A school-based eye survey including 7681 multiethnic school students aged 5 to 16 years in the southwestern part of China was conducted. Detailed ocular examinations including VA measurements, ocular motility evaluations, bilateral postcycloplegic refractions, and the assessments of the external eye, anterior segment, media, and retinal fundus were carried out by trained research vision professionals. Visual acuity was measured using a logarithm of the minimum angle of resolution E-chart, and reduced VA was defined as a presenting VA of worse than 20/40. Concentration index was initiatively utilized to measure health inequalities among different ethnic groups.

RESULTS

The prevalence of reduced VA was 11.4 per 100 children (95% confidence interval, 10.7 to 12.1%) based on the worse-seeing eye data. The prevalence of reduced VA increased with increasing age (P < .001 for trend) and was higher among girls compared with boys (P < .0001). Uncorrected refractive error was the principal cause for reduced VA, which accounted for 87.3% of the participants with reduced VA. The concentration index for reduced VA was 0.07 among different ethnic groups.

CONCLUSIONS

Compared with the estimates reported from previous studies on Chinese children and adolescents, a relatively lower prevalence of reduced VA was observed among multiethnic school students in rural China. Ethnic variations and health inequalities of reduced VA were not significant in this study.

Incidence and Types of Pediatric Nystagmus

PURPOSE

To report the incidence, prevalent subtypes, and clinical characteristics of pediatric nystagmus diagnosed over a 30-year period.

DESIGN

Retrospective, population-based study.

METHODS

Using the Rochester Epidemiology Project, we reviewed the medical records of all children (<19 years) diagnosed as residents in Olmsted County, Minnesota, with any form of nystagmus from January 1, 1976, through December 31, 2005.

RESULTS

Seventy-one children were diagnosed during the 30-year period, yielding an annual incidence of 6.72 per 100,000 younger than 19 years (95% confidence interval [CI], 5.15-8.28) Infantile nystagmus, onset by 6 months, comprised 62 (87.3%) of the study patients, corresponding to a birth prevalence of 1 in 821. The median age at diagnosis for the cohort was 12.7 months (range, 0 days to 18.6 years) and 42 subjects (59.2%) were male. The main types of nystagmus, in declining order, were nystagmus associated with retinal/optic nerve disease in 23 (32.4%), idiopathic or congenital motor nystagmus in 22 (31.0%), manifest latent nystagmus or latent nystagmus in 17 (24.0%), and 2 (2.8%) each associated with Chiari malformation, medication use, tumor of the central nervous system, and no diagnosis. Developmental delay was diagnosed in 31 (43.6%), strabismus in 25 (35.2%), and amblyopia in 10 (14.1%). Eighty percent had 20/40 (or equivalent) or better vision at presentation in at least 1 eye.

CONCLUSIONS

This study provides population-based data on incidence and clinical characteristics of childhood nystagmus in North America. Idiopathic and nystagmus associated with retinal/optic nerve disease were the most common presentations, with most patients having good vision. Developmental delay, strabismus, and amblyopia were common in this cohort.

Status and Determinants of Motor Impairment in Preschool Children from Migrant Families in China

Background

Although poor health conditions and decreased developmental levels have been investigated in migrant children, no study in China has focused on these children’s individual motor development.

Objectives

This study aims to explore the prevalence of motor impairment in Chinese migrant children and to determine the contributory factors.

Patients and Methods

In this cross-sectional study, a structured questionnaire was administered to primary caregivers of preschool children aged 3 - 6 (n = 2,976) in ten kindergartens from two districts of Suzhou, China, to assess the children’s home socioeconomic status and motor environment, that is, the presence of affordances for motor development. Motor ability was assessed using the Movement Assessment battery for children-second edition (MABC-2). Multiple logistic regression analysis was used to determine the risk factors for motor impairment in migrant children.

Results

Migrant children showed correlations with impairment in manual dexterity, aiming and catching, and motor development (odds ratios [ORs] = 1.320, 1.255, 1.260, respectively; P < 0.05). Outdoor movement affordances and toys for fine motor development were significantly associated with motor impairment in migrant children (ORs = 0.834 [movement affordances, 0.843 [toys], P < 0.05).

Conclusions

Chinese migrant children are at a high risk of motor impairment, which is associated with a lack of outdoor movement affordances and toys for fine motor development. Future prevention and intervention should focus on the motor environment of the home.

Associations between Body Mass Index and Visual Impairment of School Students in Central China

Body Mass Index (BMI) is a risk indicator for some eye diseases. However, the association between BMI and Visual Impairment (VI) was not quite certain in Chinese students. Our aim was to assess the relationship between BMI and VI with a cross-sectional study. A total of 3771 students aged 6–21 years, including 729 with VI, were sampled from 24 schools in Huangpi District of central China to participate in the study. A multistage stratified cluster random sampling was adopted. Each of the students answered a questionnaire and had physical and eye examinations. The association between BMI and VI was examined with logistic regression and threshold effect analysis. The prevalence of VI was 19.33% (729/3771). Compared to normal and underweight, overweight/obese students showed a stronger relation with VI in age- and sex-adjusted (Odds Ratio (OR) = 16.16, 95% Confidence Interval (CI): 12.37–21.09, p < 0.001) and multivariable models (OR = 8.32, 95% CI: 6.13–11.30, p < 0.001). There was a nonlinear dose–response relation between levels of BMI and the prevalence of VI (p < 0.001). A high level of BMI (≥19.81 kg/m²) was associated with a higher VI prevalence (adjusted OR = 1.20, 95% CI: 1.15–1.25, p < 0.001). In conclusion, the study demonstrated BMI levels were significantly associated with the prevalence of VI.

10-Year Overview of the Hospital-Based Prevalence and Treatment of Congenital Cataracts: The CCPMOH Experience

A review of 6 years of hospitalization charts from Zhongshan Ophthalmic Center (ZOC) revealed that congenital cataracts (CC) accounted for 2.39% of all cataract in-patient cases and that the age at surgery was decreasing before the establishment of the Childhood Cataract Program of the Chinese Ministry of Health (CCPMOH) in December 2010. We aimed to investigate data from the 4 years (January 2011 to December 2014) following the establishment of the CCPMOH, compared, and combined with data from the previous study period (January 2005 to December 2010) to generate a 10-year overview of the hospital-based prevalence and treatment of CC. In the 4-year period after CCPMOH establishment, the prevalence of CC was 2.01% in all hospitalizations, and was 2.78% in all cataract in-patients. Most of the eligible CC in-patients (71%) lived in south China. The ratio of boys to girls was 1.42:1. Nearly 2/3 of the patients underwent cataract extraction with primary intraocular lens (IOL) implantation at a mean age of 78.40±51.45 months, and cataract extraction surgeries without IOL implantation were performed in the remaining 1/3 of patients at a mean age of 10.03±15.92 months. After CCPMOH establishment, an increased incidence of CC was revealed, and the CC in-patients were younger than the patients in the previous period. The 10-year overview (2421 CC in-patients from 206630 hospitalizations) revealed upward trends in both the number and the prevalence of CC and a further reduction in age at surgery. In conclusion, the data from 4-year period after CCPMOH establishment and the 10-year overview showed upward trends in the hospital-based prevalence of CC cases and a further reduction in age at surgery, likely reflecting the effects of the CCPMOH establishment and providing useful information for further CC studies and a valuable foundation for the prevention and treatment of this cause of childhood blindness.