Parental Myopia Research Articles

Refractive error, axial length, environmental and hereditary factors associated with myopia in Swedish children

ABSTRACT Clinical relevance: Investigation of refractive errors amongst Swedish schoolchildren will help identify risk factors associated with myopia development.Background: Genetic and hereditary aspects have been linked with the development of myopia. Nevertheless, in the case of ‘school myopia’ some authors suggest that environmental factors may affect gene expression, causing school myopia to soar. Additional understanding about which environmental factors play a relevant role can be gained by studying refractive errors in countries like Sweden, where prevalence of myopia is expected to be low.Methods: Swedish schoolchildren aged 8-16 years were invited to participate. Participants underwent an eye examination, including cycloplegic refraction and axial length (AL) measurements. Predictors such as time spent in near work, outdoor activities and parental myopia were obtained using a questionnaire. Myopia was defined as spherical equivalent refraction (SER) ≤ −0.50D and hyperopia as SER ≥ +0.75D.Results: A total of 128 children (70 females and 58 males) participated in this study with mean age of 12.0 years (SD = 2.4). Based on cycloplegic SER of the right eye, the distribution of refractive errors was: hyperopia 48.0% (CI95 = 38.8-56.7), emmetropia 42.0% (CI95 = 33.5-51.2) and myopia 10.0%. (CI95 = 4.4-14.9). The mean AL was 23.1 mm (SD = 0.86), there was a correlation between SER and AL, r = −0.65 (p < 0.001). Participants with two myopic parents had higher myopia and increased axial length than those with one or no myopic parents. The mean time spent in near work, outside of school, was 5.3 hours-per-day (SD = 3.1), and mean outdoor time reported was 2.6 hours-per-day (SD = 2.2) for all the participants. The time spent in near work and outdoor time were different for different refractive error categories.Conclusion: The prevalence of myopia amongst Swedish schoolchildren is low. Hereditary and environmental factors are associated with refractive error categories. Further studies with this sample are warranted to investigate how refractive errors and environmental factors interact over time.

The cover photo shows different neovascularization types from the paper by Smid et al.

The cover photo shows different neovascularization types from the paper by Smid et al.

Association of Myopia in Elementary School Students in Jiaojiang District, Taizhou City, China.

Background The aim of our study was to evaluate the prevalence of myopia in elementary school students and to assess the risk factors for myopia. Methods This school-based cross-sectional study was performed on students from two elementary schools in Jiaojiang, Taizhou City, China. A total of 556 students, whose age ranged from 9 to 12 years, were included. The uncorrected visual acuity and noncycloplegic refractive error tests were performed to determine the myopia. Each student was asked to fulfill the questionnaire about the possible factors associated with myopia. Multivariate logistic analyses of risk factors were conducted. Results The overall prevalence of myopia among those students was 63.7%, ranged from 53.4% in grade 4 to 72.5% in grade 6. Multivariate logistic analysis showed that adjusting the height of desks and chairs according to the changing height and the presence of myopia in parents were significantly associated with myopia in these students, respectively. Conclusions Our results showed that myopia among elementary school students was associated with environmental and hereditary factors.

Effect of body stature on refraction and ocular biometry in Chinese young adults: The Anyang University Students Eye Study

ABSTRACT Clinical relevance Large‐scale data on the association between body stature with biometry parameters and refraction in young adults facilitates an understanding of myopia development. Taller persons have eyes with more negative refractions, longer axial lengths, deeper anterior chambers, flatter corneas, and higher axial length‐corneal radius ratio. Background To determine the relationship between body stature with ocular biometry and refraction in young adults. Methods This was a cross‐sectional university‐based study of 16‐ to 26‐year‐old students in China. Cycloplegic refraction and corneal curvature were measured using an autorefractor. Ocular parameters, including axial length, anterior chamber depth and lens thickness, were measured using a Lenstar LS900. Data on height and weight were acquired from an annual standardised physical examination and body mass index was calculated. Results Of 7,971 participants examined in the school clinics, 5,657 (71.0 per cent) were available in the analysis. After adjusting for age, gender, parental myopia, time outdoors, near work and weight, each centimetre of height increase was associated with more negative refraction of −0.023-D, a 0.032-mm increase in axial length, a 0.003-mm increase in anterior chamber depth, a 0.008-mm increase in corneal curvature, and a 0.001 increase in axial length‐corneal radius ratio. With regard to weight, a 1-kg heavier person was more likely to have less negative refraction of 0.011-D, a 0.001-mm increase in anterior chamber depth and a 0.002-mm increase in corneal curvature. A similar pattern of significant associations was also found in body mass index. Conclusion Taller, young adults tended to have longer eyes, deeper anterior chambers, flatter corneas, higher axial length‐corneal radius ratio, and more negative refraction, adjusted for potential confounders. In contrast, heavier and higher body mass index persons are more hyperopic. The differences in stature may partially explain the variation in refraction and ocular biometric parameters.

Relationship between peripheral refraction, axial lengths and parental myopia of young adult myopes

PurposeTo determine the relationship between peripheral refraction at the horizontal retina, axial length and parental history of myopia between myopic adults who have positive parental myopia and those with negative parental myopia. Methods69 males and 44 females in the age range of 18–25 years were assigned either a negative parental myopia (NPM) or positive parental myopia (PPM) group. In the corrected and uncorrected states, peripheral refractive error was measured up to 30° horizontally in 10° steps using an open field autorefractor. Axial length was measured using an Opto US1000 Fine A-Scan Ultrasonography (model US1000). ResultsRelative peripheral refractive error showed more hyperopic defocus that was statistically significantly more increased in the positive parental myopia group than in the negative parental myopia group (P ≥ 0.02). The overall mean ± SD axial length of all subjects was 23.38 ± 0.32 mm (range 23.01–25.01 mm). The study showed a statistically significant difference (P = 0.005) in axial lengths of young adult myopes (23.45 ± 0.36 mm) with parental myopia compared to those with similar spherical equivalent refraction who have non-myopic parents (23.28 ± 0.19 mm). ConclusionThere was significantly more hyperopic defocus at 30° N and 30° T retina in the corrected states of young adult myopes who had myopic parents compared to their counterparts with non-myopic parents.

Age Effect on Treatment Responses to 0.05%, 0.025%, and 0.01% Atropine: Low-Concentration Atropine for Myopia Progression Study

To investigate the effect of age at treatment and other factors on treatment response to atropine in the Low-Concentration Atropine for Myopia Progression (LAMP) Study. Secondary analysis from a randomized trial. Three hundred fifty children aged 4 to 12 years who originally were assigned to receive 0.05%, 0.025%, or 0.01% atropine or placebo once daily, and who completed 2 years of the LAMP Study, were included. In the second year, the placebo group was switched to the 0.05% atropine group. Potential predictive factors for change in spherical equivalent (SE) and axial length (AL) over 2 years were evaluated by generalized estimating equations in each treatment group. Evaluated factors included age at treatment, gender, baseline refraction, parental myopia, time outdoors, diopter hours of near work, and treatment compliance. Estimated mean values and 95% confidence intervals (CIs) of change in SE and AL over 2 years also were generated. Factors associated with SE change and AL change over 2 years were the primary outcome measures. Associated factors during the first year were secondary outcome measures. In 0.05%, 0.025%, and 0.01% atropine groups, younger age was the only factor associated with SE progression (coefficient of 0.14, 0.15, and 0.20, respectively) and AL elongation (coefficient of -0.10, -0.11, and -0.12, respectively) over 2 years; the younger the age, the poorer the response. At each year of age from 4 to 12 years across the treatment groups, higher-concentration atropine showed a better treatment response, followinga concentration-dependent effect (Ptrend <0.05 for each age group). In addition, the mean SE progression in 6-year-old children receiving 0.05% atropine (-0.90 diopter [D]; 95% CI, -0.99 to -0.82) was similar to that of 8-year-old children receiving 0.025% atropine (-0.89 D; 95% CI, -0.94 to -0.83) and 10-year-old children receiving 0.01% atropine (-0.92 D; 95% CI, -0.99 to -0.85). All concentrations were well tolerated in all age groups. Younger age is associated with poor treatment response to low-concentration atropine at 0.05%, 0.025%, and 0.01%. Among concentrations studied, younger children required the highest 0.05% concentration to achieve similar reduction in myopic progression as older children receiving lower concentrations.

Longitudinal association between myopia and parental myopia and outdoor time among students in Wenzhou: a 2.5-year longitudinal cohort study

BackgroundTo evaluate the impact of parental myopia and outdoor time on myopia among students in Wenzhou.MethodsWe examined 1388 primary students from first grade to third grade in Wenzhou from September 2012 to March 2015. We performed noncycloplegic refractometry on each student every six months and axial length (AL) measurements every year. At the commencement of our study, children were asked to complete a questionnaire regarding near work activity and outdoor activity, whereas parents were asked to complete a self-administered questionnaire regarding their background circumstances and their history of myopia.ResultsA total of 1294 students (93.2%) returned for follow-up examinations. Children with initial and final no myopia spent more time on outdoor activities than those with new onset myopia (1.92 vs. 1.81 h/d, p = 0.022), and elongation of AL in children with a high level (> 2.5 h/day) of outdoor time (0.22 ± 0.13 mm/Y) was less than those with a low level (≤ 1.5 h/day) of outdoor time (0.24 ± 0.14 mm/Y, p = 0.045). The proportion of rapid myopia progression (≤-0.5D/Y) was 16.7%, 20.2% and 31.5% among the children with no myopic parent, one myopic parent and two myopic parents, respectively (X2 = 28.076, p < 0.001), and the elongation of AL in children among different numbers of myopic parents was significantly different (p < 0.001). A high level of outdoor time was a protective factor for children with one myopic parent (HR 0.49, 95% CI 0.27–0.88; p = 0.018).ConclusionsIn this sample, parental myopia and outdoor time were associated with myopia in children. A high level of outdoor time was a protective factor for children with one myopic parent.

Smartphone use as a possible risk factor for myopia

ABSTRACT Clinical relevance This study demonstrates an association between myopia and smartphone data usage. Youths now spend more time participating in near tasks as a result of smartphone usage. This poses an additional risk factor for myopia development/progression and is an important research question in relation to potential myopia management strategies. Background Children are now exposed to another possible environmental risk factor for myopia – smartphones. This study investigates the amount of time students spend on their smartphones and their patterns of smartphone usage from a myopia perspective. Methods Primary, secondary and tertiary level students completed a questionnaire exploring patterns of smartphone usage and assessing their attitudes toward potential myopia risk factors. Device‐recorded data usage over an extended period was quantified as the primary and objective indicator of phone use. Average daily time spent using a smartphone was also quantified by self‐reported estimates. Refractive status was verified by an optometrist. Results Smartphone ownership among the 418 students invited to participate was over 99-per cent. Average daily smartphone data and time usage was 800.37 ± 1,299.88-MB and 265.16 ± 168.02-minutes respectively. Myopic students used almost double the amount of smartphone data at 1,130.71 ± 1,748.14-MB per day compared to non‐myopes at 613.63 ± 902.15-MB (p = 0.001). Smartphone time usage was not significantly different (p = 0.09, 12-per cent higher among myopes). Multinomial logistic regression revealed that myopic refractive error was statistically significantly associated with increasing daily smartphone data usage (odds ratio 1.08, 95% CI 1.03–1.14) as well as increasing age (odds ratio 1.09, 95% CI 1.02–1.17) and number of myopic parents (odds ratio 1.55, 95% CI 1.06–2.3). Seventy‐three per cent of students believed that digital technology may adversely affect their eyes. Conclusion This study demonstrates an association between myopia and smartphone data usage. Given the serious nature of the ocular health risks associated with myopia, our findings indicate that this relationship merits more detailed investigation.

Study at Home During COVID-19 Lockdown Is Associated with a Dramatic Increase in the Prevalence of Myopia in Hong Kong Children

Background: Due to the COVID-19 pandemic, schools in Hong Kong were closed down for four months. During this period, local schools devised online learning resources for students to study at home. While the demand to access this online resource may directly increase screen time, it was unknown whether it would promote myopia development. We compared the results of vision screening conducted in the same primary school for 8-10 year-old children before and after the COVID-19 pandemic. Methods: This was a cross sectional study. Two vision screenings, targeted at children aged 8 to 10 years old, were conducted in the same primary school in October 2018 and June 2020. Non-cycloplegic refraction and axial length were measured by an open‐field auto‐refractometer (Shin‐Nippon, NVision K5001, Japan) and an IOL Master (Carl Zeiss Meditec AG, Germany), respectively. A questionnaire focusing on risk factors of myopia was completed by parents of participants. Findings: There were no significant differences in age, gender, monthly family income, or parental myopia between the two cohorts. Alarmingly, the overall myopia proportion (SE ≤ -1·00 D) was significantly higher after the school lockdown (75·7% vs 37·5%, Chi-square test, 𝜒 2 = 40·758,&|amp;|lt;0·001). In addition, the axial length (23·64±1·00 mm vs. 23·39±0·89 mm, unpaired t-test, t = -2·151, p=0·02) and time spent on handheld digital devices (1·40 hrs/day vs. 1·60 hrs/day, Mann-Whitney U test, U=7590·5, p=0·01) were both significantly higher over this period. Interpretation: A dramatic increase in myopia proportion was noted after the school lockdown period. Increased screen time may contribute to an increased risk of myopia development among other potential risk factors. Funding: Center for Myopia Research, School of Optometry, The Hong Kong Polytechnic University. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This study followed the tenets of the Declaration of Helsinki and was approved by the ethics committee of The Hong Kong Polytechnic University (HSEARS20180726001). Informed written consent was obtained from parents after explaining the nature and purpose of the study.

Axial growth and refractive change in white European children and young adults: predictive factors for myopia

This report describes development of spherical equivalent refraction (SER) and axial length (AL) in two population-based cohorts of white, European children. Predictive factors for myopic growth were explored. Participants were aged 6–7- (n = 390) and 12–13-years (n = 657) at baseline. SER and AL were assessed at baseline and 3, 6 and 9 years prospectively. Between 6 and 16 years: latent growth mixture modelling identified four SER classes (Persistent Emmetropes-PEMM, Persistent Moderate Hyperopes-PMHYP, Persistent High Hyperopes-PHHYP and Emerging Myopes-EMYO) as optimal to characterise refractive progression and two classes to characterise AL. Between 12 and 22-years: five SER classes (PHHYP, PMHYP, PEMM, Low Progressing Myopes-LPMYO and High Progressing Myopes-HPMYO) and four AL classes were identified. EMYO had significantly longer baseline AL (≥ 23.19 mm) (OR 2.5, CI 1.05–5.97) and at least one myopic parent (OR 6.28, CI 1.01–38.93). More myopic SER at 6–7 years (≤ + 0.19D) signalled risk for earlier myopia onset by 10-years in comparison to baseline SER of those who became myopic by 13 or 16 years (p ≤ 0.02). SER and AL progressed more slowly in myopes aged 12–22-years (− 0.16D, 0.15 mm) compared to 6–16-years (− 0.41D, 0.30 mm). These growth trajectories and risk criteria allow prediction of abnormal myopigenic growth and constitute an important resource for developing and testing anti-myopia interventions.

Prenatal and neonatal factors for the development of childhood visual impairment in primary and middle school students: a cross-sectional survey in Guangzhou, China

ObjectivesIn this cross-sectional survey, we sought to determine the prevalence of and the influence of prenatal and neonatal factors on childhood visual impairment without correction (VIUC) in a paediatric population...

Comparison of myopic progression in Finnish and Singaporean children

To compare 3-year myopic progression between Finnish and Singaporean children. Myopic progression was compared between 9-year-old (mean age 9.7±0.4years, n=92) and 11-year-old (mean age 11.7±0.4years, n=144) Finnish (Finnish RCT) children and Singaporean children matched by age and refraction (SCORMMatched, n=403) and 7- to 8-year-old Singaporean children matched only by refraction (SCORM Young, n=186). Spherical equivalent (SE) was between -0.50 and -3.00 D. Refraction with cycloplegia was controlled annually for 3years. Information on parental myopia, mother's education, time spent on near-work and outdoor time was gathered by parental questionnaire. Three-year myopic progression was -2.08±0.96 D and -1.30±0.69 D in the Finnish RCT and Singaporean SCORM Matched 9-year-olds, respectively, and -1.34±0.78 D, and -0.52±0.44 D in the 11-year-olds, respectively (p<0.001 between all groups). Myopic progression was fastest (-2.69±0.89 D) in the SCORM 7-year-olds and similar between the SCORM Matched 9-year-olds and Finnish RCT 11-year-olds (p=0.55). The Finnish RCT and SCORM Matched children showed significant differences in both daily near-work time (1.8±1.0 versus 3.4±1.9hours per day, p<0.001) and outdoor time (2.6±0.9 versus 0.5±0.4hours per day, p<0.001). These differences did not, however, explain the differences in myopic progression between the groups. More time spent outdoors was associated with less myopic progression in the Finnish RCT (r=0.17, p=0.009) group only. In the whole materials, greater myopic progression was associated with younger age at baseline (p<0.001), younger age was associated with mother's higher education (p<0.001), and mothers higher education was associated with myopia in both parents (p<0.001). Age at baseline was the most significant factor associated with myopic progression. However, at the same age and with the same initial refraction, the Finnish and Singaporean children showed different myopic progression. This result remains unexplained. Thus, age of myopia onset should be considered when comparing myopic progression between different samples and conducting treatment trials. Parental myopia may be a weak indicator of heredity of myopia.

Myopia in school-aged children with preterm birth: the roles of time spent outdoors and serum vitamin D

AimsTo analyse the factors associated with myopia in school-aged children with preterm birth and with or without retinopathy of prematurity (ROP).MethodsChildren born prematurely between January 2010 and December 2011 were...

Is Dietary Vitamin A Associated with Myopia from Adolescence to Young Adulthood?

PurposePotential links may exist between vitamin A intake and myopia via various pathways. In this study, we examined the association between dietary vitamin A intake during adolescence and myopia in early adulthood.MethodsWe performed a prospective analysis utilizing data collected from participants of the Raine Study Gen2. Dietary vitamin A intake, determined via food frequency questionnaires completed at ages 14, 17, and 20 years, was compared with ophthalmic measurements collected at year 20. Low vitamin A levels were defined as <600 µg/day. Regression models were used to adjust for ocular sun exposure level, educational level, and parental myopia as potential confounders.ResultsA total of 642 subjects were analyzed. Although those with adequate vitamin A intakes were less likely to be myopic (P = 0.03), this association became insignificant when adjusted for potential confounding factors in logistic regression modeling (odds ratio, 0.59; 95% confidence interval, 0.98–2.52; P = 0.06).ConclusionsThere were no significant associations between total vitamin A intakes during adolescence and year 20 refractive errors after adjustment for confounders. Replication of this finding and further investigations are essential to rule out the suggestion that sufficient vitamin A intake during adolescence is associated with lower risk of myopia in early adulthood.Translational RelevanceOur findings are not definitive that ingesting foods high in vitamin A during childhood and adolescence does not have a role for preventing myopia in early adulthood.

Independent Influence of Parental Myopia on Childhood Myopia in a Dose-Related Manner in 2,055 Trios: The Hong Kong Children Eye Study

To determine the effects on childhood myopia of parental myopia, parental education, children's outdoor time, and children's near work. Population-based cross-sectional study. A total of 6,155 subjects in 2,055 family trios (1 child and both parents). Cycloplegic autorefraction was measured for children and noncycloplegic autorefraction for parents. Parental education, children's outdoor time, and near work were collected by questionnaires. Children were categorized into 10 groups based on parental myopia levels. Associations of the above factors with myopia were evaluated by regression analyses. The areas under the receiver operating characteristic curve (AUROCs) for myopia were evaluated. Mild parental myopia did not increase childhood myopia's risk, but the risk was 11.22-folds when both parents were highly myopic. Higher parental education (Father: OR 1.08, P= .046; Mother: OR 1.11, P= .001) and more reading time of children were risk factors (OR 1.21, P= .044). Reduced odds of myopia were associated with more time spent on outdoor activities (OR 0.78, P= .017). Notably, all these factors became insignificant after adjustment, except for parental myopia. Children with more severe parental myopia spent more time on reading, but less on electronic devices. Parental myopic status alone accounted for 11.82% of myopia variation in children. With age and parental myopia, the AUROC for myopia was 0.731. Among parental and environmental factors, parental myopia confers, in a dose-related manner, the strongest independent effect on childhood myopia. Therefore children with high risk of myopia can be identified for early prevention, based on parental myopia data.

Relationship between peripapillary atrophy and myopia progression in the eyes of young school children.

Myopia progression is of great concern because of its association with an increased risk of sight-threatening conditions. This study aims to determine whether certain clinical and optic disc features are associated with the rate of myopia progression. In this retrospective longitudinal observational study, we reviewed the medical records of 95 patients aged 6-11 years with myopia (spherical equivalent refractive error (SER) at baseline ≤ -0.5 D) and collected data regarding medical history, comprehensive ophthalmologic examination, and fundus photography. Using fundus photographs, we measured the ratio of horizontal to vertical disc diameter (HVDR), ratio of maximum β-zone peripapillary atrophy (β-PPA) width to vertical disc diameter (PVDR), and optic disc torsion. Outcome measurements included 2-year myopia progression (D/year) and overall myopia progression during the entire follow-up with a mean of 51 months. Mean age at initial visit was 7.67 ± 1.50 years and mean SER at baseline was -2.91 ± 1.68 D (range, -5.75 to -0.50 D). In the univariate analysis, age, parental myopia, SER at baseline, HVDR, and PVDR were significantly associated with myopia progression (P < 0.05). In the multivariate analysis, however, only age at initial visit and PVDR were significant factors associated with both 2-year and overall myopia progression. Children with younger age and smaller β-PPA at baseline showed a faster myopia progression. This study suggests that the width of β-PPA, regardless of SER, might be used as a quantitative parameter to predict the potential for further myopia progression associated with scleral stretching.

Prevalence of myopia among secondary school students in Welkite town: South-Western Ethiopia

BackgroundRefractive error, especially myopia, is the most common eye disorder in the world and a significant cause of correctable visual impairment. The aim of this study was to assess the prevalence of myopia among secondary school students in Welkite town, South-Western Ethiopia.MethodsA school based cross sectional study was carried out among secondary school students of 13 to 26 years of age. The students were selected using a multi stage-stratified cluster sampling technique from four secondary schools. The students’ socioeconomic background, usage of eyeglasses and parental myopia was assessed by a questionnaire before visual acuity assessment. Students with visual acuity of less than or equal to 6/12 in the worse eye, who showed vision improvement with pinhole, underwent non-cycloplegic retinoscopy and subjective refraction. Myopia was defined as a spherical equivalent of less than or equal to − 0.50 diopters. Logistic regression was used to see the association of myopia with age, sex, grade level, ethnicity, parental history of myopia and severity.ResultsA total of 1271 students with a response rate of 89.4% were evaluated. The mean age was 16.56+ 1.51 years. Eighty three students were identified to have myopic refractive error making the prevalence of 6.5% (95% CI: 5.30, 8.02). Of 648 females, 50 (7.7%) had myopia while 33 (5.3%) of 623 males had myopia making females relative risk to be 1.5 times that of males. From the total students diagnosed to have refractive error (n = 92), myopia constituted 83/92 (90.2%) of the students indicating that it is the commonest type of refractive error found amongst secondary school students. Only 36.1% of students with myopia wore eyeglasses when they attended the survey. Myopia was more common among older age group 17–21 years (OR: 1.54 95% CI 0.986–2.415) and higher grade level 11–12 (OR: 1.14 95% CI 0.706–1.847).ConclusionsThe prevalence of myopia is high in our study. Attention to the correction of myopia in secondary schools students of Welkite town using eyeglasses can prevent a major proportion of visual impairment.

Puberty could regulate the effects of outdoor time on refractive development in Chinese children and adolescents

AimTo explore the impact of puberty on refractive development and its interaction with outdoor time in children and adolescents.MethodsIn this 2-year observational study, students aged 7–13 years were selected with...

Prevalence of myopia and associated risk factors among primary students in Chongqing: multilevel modeling

BackgroundThe prevalence of myopia and associated risk factors among children in Chongqing has not yet been determined. This study investigated the prevalence of myopia and possible relationships between myopia and several related factors among school children in Chongqing.MethodsThis cross-sectional study assessed a sample of 997 children (7–13 years of age) attending primary school in Chongqing. Data were obtained from visual acuity and refractive error measurements and a structured questionnaire. Myopia was defined as visual acuity < 5.0 and refractive error (spherical equivalent) of < − 0.50 diopters (D) in either eye. Multilevel modeling was applied to investigate potential risk factors.ResultsThe overall prevalence of myopia was 33.9% [95% confidence interval (CI) = 31.0–36.8]; myopia prevalence significantly increased with age. Girls were at a higher risk of myopia than boys [odds ratio (OR) = 1.449, 95% CI = 1.060–1.979]. Children with paternal myopia (OR = 2.130, 95% CI = 1.376–3.297) or maternal myopia (OR = 1.861, 95% CI =1.153–3.002) had a higher risk of myopia than those without myopic parents. Children who spent more than 1 h daily outdoors were less likely to have myopia; meanwhile, children who did homework more than 3 h daily (OR = 2.237, 95% CI = 1.041–4.804), watched television more than 3 h daily (OR = 2.106, 95% CI = 1.200–3.697), or played electronics more than 1 h daily (OR = 2.983, 95% CI = 2.088–4.262) had a higher risk of myopia.ConclusionsMyopia in school children is a serious public health problem in Chongqing. Myopia was significantly positively associated with higher age, female sex, parental myopia, and spending a long time indoors; notably, playing with electronics had the greatest influence on the risk of myopia.

Western Australia Atropine for the Treatment of Myopia (WA‐ATOM) study: Rationale, methodology and participant baseline characteristics

Atropine eyedrops are a promising treatment for slowing myopia progression in East Asian children. However, its effects on children in Australia, including those of non-Asian background, have not been well-studied. The Western Australia Atropine for the Treatment of Myopia (WA-ATOM) study aims to determine the efficacy and long-term effects of low-dose atropine eyedrops in myopia control. This paper describes the study rationale, methodology and participant baseline characteristics. Single-centre, double-masked, randomized controlled trial. Children (6-16 years) with spherical equivalent ≤-1.50 D in each eye, astigmatism ≤1.50 D and myopia progression by ≥0.50 D/year. Enrolled children were randomly assigned 2:1 to receive 0.01% atropine or placebo eyedrops. Participants are examined every 6 months during first 3 years of the study (2-year treatment phase followed by a 1-year washout phase), and then at a 5-year follow-up (2 years after the end of the washout phase). Annual progression rate of myopia and axial length, tolerability to eyedrops and incidence and severity of unwanted effects. Out of 311 children who were referred, 242 were suitable for study participation, and 153 were subsequently enrolled. The baseline characteristics of enrolled participants are presented. Outcomes of the WA-ATOM study will inform on the efficacy, tolerability, safety and long-term effects of low-dose atropine eyedrops in myopia control in Australian children. The impact of ocular sun exposure, iris colour and parental myopia on the efficacy of low-dose atropine will also be assessed.