Chinese School Children Research Articles

Evaluating the myopia progression control efficacy of defocus incorporated multiple segments (DIMS) lenses and Apollo progressive addition spectacle lenses (PALs) in 6- to 12-year-old children: study protocol for a prospective, multicenter, randomized controlled trial

BackgroundMyopia is increasing in prevalence and is currently recognized as a significant public health issue worldwide, particularly in China. Once myopia develops, appropriate clinical interventions need to be prescribed to slow its progression. Currently, several publications indicate that myopic defocus (MD) retards eye growth and myopia progression. However, no clinical trials have compared the outcomes of different MD spectacle lenses in the same observational group, especially in mainland China. The aim of the present study is to compare the myopia control efficiency of two different MD spectacle lenses: defocus incorporated multiple segments (DIMS) lenses and Apollo progressive addition lenses (PALs).MethodsThe trial is designed as a 3-year, prospective, randomized, multicenter clinical trial of schoolchildren treated with DIMS lenses and PALs. A total of 600 Chinese primary school children aged 6–12 years will be recruited, and each group is intended to include 300 subjects. The inclusion criteria are myopia between − 1.00 and − 5.00 diopters and astigmatism ≤ 1.50 diopters. The follow-up time points will be 1 month (m), 3 m, 6 m, 12 m, 18 m, 24 m, 30 m, and 36 m. The primary outcome will be determined by the difference between the two groups in cycloplegic spherical equivalent refraction between baseline and the last follow-up visit. The secondary outcome is the axial length, and the exploratory outcomes include ocular biometric measures, peripheral refraction, binocular vision, accommodation, compliance, and the results of questionnaires related to wearing experiences.DiscussionThe present study will be the first randomized controlled trial in myopic primary school children treated with DIMS lenses and PALs in China. The results will indicate whether and how much different MD mechanisms retard myopia progression and axial elongation. In addition, the comparison will provide information on the clinical efficacy and safety of DIMS lenses and PALs, including information related to wearing experiences and visual function.Trial registrationChinese Clinical Trial Registry (ChiCTR), ChiCTR1900025645. Registered on 3 September 2019. http://www.chictr.org.cn/showproj.aspx?proj=42927.

The prevalence of behavioral and emotional problems among Chinese school children and adolescents aged 6-16: a national survey.

Improving the mental health of children and adolescents is a critical priority in China. However, only minimal information is available concerning the prevalence of mental disorders. In the present study, a two-stage national survey has been completed in five regions of China. In the first stage, data from the Achenbach Child Behavior Checklist (CBCL) were collected for each participant to identify the prevalence of the behavioral and emotional problems in China. A multistage cluster stratified random sampling design was used, and a total of 71,929 individuals aged 6-16years were collected. In this large cohort, 36,893 (49.86%) were males, and 49,015 (66.24%) were living in urban communities. Overall, 17.6% (90% confidence interval 17.4%, 17.9%) of the children and adolescents were identified as having behavioral and emotional problems. Moreover, age and sex effect was found for the CBCL scores. The boys' cohort had a higher prevalence of behavioral and emotional problems than girls (18.6% versus 16.6%). In the older cohort aged 12-16, the prevalence was higher than for the younger cohort aged 6-11 (19.0% versus 15.9%). Notably, it seems that the prevalence of the behavioral and emotional problems for children and adolescents had a rise in the past 30years, but the scarcity of pediatric psychiatrists in China needs to be addressed. To reduce the behavioral and emotional problems, the whole society, including mental health providers, educators, and parents, needs to focus on and pay more attention to it. It will have long-term benefits for China.

Associations between perceived and actual physical literacy level in Chinese primary school children

BackgroundThe concept of physical literacy (PL) is gaining popularity within public health and physical education circles. However, little is known about the relationship between perceived and actual PL levels among school-aged children. The aim of this study is to explore the associations between perceived and actual levels of PL of primary school students in China.MethodsA total of 327 children (153 boys and 174 girls) with a mean (SD) age of 10.0 (±1.0) years were included for analysis. PL perceptions were measured using the Perceived Physical Literacy Instrument. Children’s actual level of PL was objectively assessed by the Chinese version of the Canadian Assessment of Physical Literacy, 2nd edition, which consists of four domains: Daily Behavior, Physical Competence, Motivation and Confidence, and Knowledge and Understanding. Pearson’s correlation coefficients were calculated to examine the relationship between students’ perceived and actual PL levels, whereas Multivariate Analysis of Variance (MANOVA) was calculated to investigate the gender, relative age differences, and interaction effect (2 × 4) on perceived and actual PL levels respectively.ResultsSignificant correlations were observed between the perceptions and actual PL scores in both boys (r = .46, p < .01) and girls (r = .41, p < .01). Low to moderate significances were shown between each domain of perceived PL and actual PL (from .16 to .49). Further MANOVA results revealed that there were significant gender differences in the Daily Behavior domain of actual PL (F (1, 319) = 30.15, p < .001, Wilks’ Λ = 540.88, η2partial = .09). Overall, boys had both higher actual PL scores (58.9) and PL perceptions (37.3) than girls. Neither relative age effect nor interaction effect (2 × 4) was observed for the current participants in all the variables.ConclusionsThis study is the first to examine the associations between the perceived and actual levels of PL in Chinese children. Additional studies should explore the importance of children’s perceptions of PL when assessing the actual level of PL in physical education and health settings. Girls should be more encouraged by PE teachers to participate actively in physical activities in the school environment.

Saliva cortisol, melatonin levels and circadian rhythm alterations in Chinese primary school children with dyslexia

Cortisol is the main end product of hypothalamic-pituitary-adrenal gland (HPA axis), and melatonin (MT) has a regulating effect on HPA axis, and both are closely related to individual behavior and cognitive function. We aimed to evaluate cortisol and MT roles on children dyslexia in this study.A total of 72 dyslexic children and 72 controls were recruited in this study. Saliva samples were collected in the morning, afternoon, and night, respectively. The levels of saliva cortisol and MT were measured by enzyme-linked immunosorbent assay method. Differences of cortisol and MT levels between dyslexic and normal children were compared, and the variation trend was also analyzed by dynamic monitoring in 3 time points.The levels of salivary cortisol and MT in children with dyslexia were all lower than those in normal children whether in the morning (7:30-8:30 am ), at afternoon (15:30-16:30 pm ) or at night (21:30-22:30 pm ) (all P < .001). Compared with normal children, the circadian rhythm variations of salivary cortisol and MT in dyslexic children disappeared and became disordered. The salivary cortisol and MT levels in children with dyslexia were declined throughout the day; and the circadian rhythm was disordered or disappeared.The results suggest that cortisol and MT levels and their circadian rhythm may affect children dyslexia, but the mechanisms need further exploration.

Anaemia, iron deficiency, iron-deficiency anaemia and their associations with obesity among schoolchildren in Guangzhou, China.

The association of Fe metabolism with obesity in children remains unclear. The present study aimed to assess the status of Fe metabolism parameters, the prevalence of anaemia, Fe deficiency (ID) and Fe-deficiency anaemia (IDA), and the associations of these variables with obesity in Chinese schoolchildren. A cross-sectional study conducted in 5295 schoolchildren aged 7-11 years in Guangzhou, China, 2014-2015. Full data of anthropometric and Fe metabolic parameters were collected to assess obesity, anaemia, ID and IDA. Logistic regression models were established to determine the possible associations of anaemia, ID and IDA with obesity. Two-tailed P values of <0·05 was considered statistically significant. Guangzhou City, China. Schoolchildren aged 7-11 years (n 5295). In this sample, mean Hb concentration was 128·1 g/l and the prevalence of anaemia, ID and IDA was 6·6, 6·2 and 0·6 %, respectively. Of the participants, 14·0 % were overweight and 8·8 % were obese. Importantly, obesity was associated with lower anaemia risk (adjusted OR = 0·553; 95 % CI 0·316, 0·968) but higher ID risk (adjusted OR = 1·808; 95 % CI 1·146, 2·853) after adjustment for confounders. No significant relationship was found between obesity and IDA. Our results confirmed that anaemia and ID remain public health concerns among schoolchildren in Guangzhou, while IDA is remarkably less prevalent. Furthermore, obesity was associated with lower anaemia risk, but higher ID risk. More efforts should be made to prevent the onset of ID and obesity in the same individual, thus improving the health and fitness of children.

Efficacy and Safety of 1% Atropine on Retardation of Moderate Myopia Progression in Chinese School Children.

Background: To evaluate the long-term efficacy and safety of topical 1% atropine for retarding moderate myopia.Methods: A randomized, controlled study evaluating atropine and placebo in 660 Chinese children. Patients received drops q1month for 24 months, then q2month for 12 months, followed by no drops for 12 months. Spherical equivalent, axial length, intraocular pressure and atropine-related side effects were examined at 6, 12, 24, 36 and 48 months for all children.Results: Spherical equivalent, myopic progression, axial length augmentation, and progression rate were significantly reduced in the atropine group than those in the placebo group (all P<0.05), indicating that 1% atropine effectively retarded myopia. Moreover, myopic rebound and adverse effects of 1% atropine were eliminated by gradual withdrawal and elimination of 1% atropine. Furthermore, pupil size, near visual acuity, and amplitude of accommodation returned to pretreatment levels after withdrawal of atropine.Conclusion: Topical 1% atropine periodically and alternatively in phase I with gradual reduction in phase II and final withdrawal in phase III may effectively improve atropine efficacy, retard moderate myopia, reduce atropine side effects, minimize myopic rebound, and increase compliance of children simultaneously.

GWAS-identified variants to allergic disease and early environmental exposure in Chinese schoolchildren with allergic rhinitis induced by house dust mite.

There is growing evidence that environmental exposure in early life is associated with the development of childhood allergic rhinitis. To investigate whether polymorphisms in previously published genome wide association studies (GWAS) allergic disease loci are associated with childhood house dust mite-induced allergic rhinitis (HDM-AR) and interaction effects of genetic and environmental factors on it. 156 cases diagnosed by HDM-AR and 173 controls were enrolled. Potential confounders were analyzed by using Logistic regression. Twenty-one single nucleotide polymorphisms (SNPs) of GWAS-related allergic diseases including EMSY-LRRC32, IL18R1, IL18RAP, IL13, IL4, HLA region, KIF3A were genopyped and analyzed using the improved multiplex ligation detection reaction (imLDR) technique in all the subjects. Only IL18R1_rs2287037 was associated with HDM-AR in children. After adjusting for several likely confounders, the protective TT genotype of IL18R1_rs2287037 was found in the population analyzed with the fittest recessive model. (adjusted odds ratio [aOR]: 0.44; 95% confidence interval [CI]: 0.21-0.95). The rs2287037_ TT might interact with early-life exclusive breastfeeding in the first 4 months (aOR: 0.33; 95%CI: 014-0.97) or full-term birth (aOR: 0.45; 95%CI: 0.19-0.95) exposure to decrease the risk of HDM-AR. These data suggest that IL18R1 polymorphism may play a role in controlling risk to HDM-AR and underline the importance of early environmental exposure into studies of genetic risk factors.

Prenatal and neonatal factors involved in the development of childhood allergic diseases in Guangzhou primary and middle school students

BackgroundAllergic diseases, such as asthma, dermatitis, rhinitis, and eczema, are highly prevalent in Chinese school children. Environmental factors, including air pollution and automobile exhaust, play an important role in the etiology of these diseases. However, prenatal and neonatal factors, such as gender, maternal diseases during pregnancy, and premature birth, may also be associated with allergic disease occurrence. The objective of this study was to explore prenatal and neonatal factors that are involved in the development of allergic diseases among primary and middle school students in Guangzhou, China.MethodsA cross-sectional survey was launched by the Health Promotion Centre for Primary and Secondary Schools of the Guangzhou Municipality in October 2017. All primary and middle school students in Guangzhou were notified to participate in the questionnaire online under the direction of their parents. The results of the physical examination were reported by the schools’ medical department. The results of the questionnaire were collected and analyzed by the researchers. The prevalence of asthma, allergic rhinitis, allergic dermatitis, and eczema was identified.ResultsBased on reported 183,449 questionnaires and medical records, the data indicate that the sex, birth weight, neonatal feeding type, delivery mode, and students’ father smoking status were significantly associated with the prevalence of all four allergic diseases in primary and middle school children. In further stratified analyses of the children with normal birth weight (2500–4000 g) and without any maternal diseases during pregnancy, the factors of male sex, high birth weight, cesarean delivery, and father smoking status all increased the risk of asthma, dermatitis, rhinitis, and eczema. Also, unlike exclusive breastfeeding, breast plus formula feeding increased these risks, but pure formula feeding had the opposite effect.ConclusionPrenatal and neonatal factors, including male sex, high birth weight, cesarean delivery, only child, and father smoking status are associated with the risks of allergic diseases in school children.

Prevalence of malocclusion in Chinese schoolchildren from 1991 to 2018: A systematic review and meta-analysis.

Malocclusion is a common oral health problem in schoolchildren. Literature describing the prevalence of malocclusion varies substantially across China. This study identified the epidemiological characteristics of malocclusion among Chinese schoolchildren from 1991 to 2018. Six English and Chinese electronic databases were searched through November 2018. The search was supplemented by hand searching to identify relevant surveys. The overall prevalence of malocclusion was estimated by a random-effects meta-analysis model, and variations in different groups were assessed by subgroup meta-analysis. Thirty-seven eligible articles describing 117682 samples were investigated. The pooled national prevalence for malocclusion was 47.92% (95% CI: 58.6%-71.9%). For the Angle classification, the overall prevalence rates were 30.07% (95% CI: 25.37%-35.48%), 9.91% (95% CI: 7.41%-13.79%), and 4.76% (95% CI: 3.85%-6.54%) for Class I, Class II, and Class III malocclusion, respectively. A deep overbite (16.67%, 95% CI: 11.50%-23.08%) was shown to be the most common trait of malocclusion. When stratified by sex, males had a slightly higher prevalence than females (RR=1.04, 95% CI: 1.01-1.06). More importantly, an ascending trend and substantial variations across the country were observed. Our results confirmed that malocclusion has become a serious oral health problem in Chinese schoolchildren, highlighting the need for proactive interventions at an early age. Moreover, high-quality epidemiological studies on malocclusion are still required.

Education, Altitude, and Humidity Can Interactively Explain Spatial Discrepancy and Predict Short Stature in 213,795 Chinese School Children.

Backgrounds and Objectives: The north–south height distinctions in Chinese children suggest that some geographical–climatic factors could determine height variation of short stature. In a national health survey, we aimed to explore the spatial distribution of short stature on city scales, and detect its socio-economic and geographical–climatic factors.Methods: Data on the prevalence of short stature were obtained from a 2014 cross-sectional survey of China (CNSSCH). In total, 213,795 Han Chinese students aged 7–18 years, from 106 cities across 30 provinces, were included. Both China and World Health Organization (WHO) growth references were adopted to define short stature.Results: A spatial clustering was apparent in the distribution of short stature. After multivariable adjustment, altitude and humidity significantly increased the risk of high prevalence in short stature, according to the WHO (odds ratio [OR] = 1.61 and 1.26, 95% confidence interval [CI]: 1.20–2.17 and 1.03–1.54) and China (OR = 1.54 and 1.26; 95% CI: 1.15–2.05 and 1.02–1.55) growth references. Additionally, education significantly decreased the risk of high prevalence in short stature according to the WHO (OR = 0.40; 95% CI: 0.22–0.74) and China (OR = 0.42; 95% CI: 0.22–0.77) growth references. Combining both altitude >400 m and education <9 years, as well as education <9 years and humidity >70%, received the largest effect-size estimate, and significance retained after multivariable adjustment.Conclusions: Our findings indicate that high altitude and humidity increased the risk of high prevalence in short stature, high education was associated with low prevalence. Additionally, we observed possible interactions between education and altitude/humidity. They may interactively explain spatial discrepancy and predict short stature in Chinese school children. Further validations are necessary.

Incidence, risk factors and psychosomatic symptoms for traditional bullying and cyberbullying in Chinese adolescents

IntroductionThe objectives were to determine the prevalence and risk factors of traditional bullying and cyberbullying in Chinese middle school children, and to explore the association between bullying and psychosomatic symptoms. MethodsThis cross-sectional study was conducted in urban and rural areas in Chongqing, Henan and Zhejiang provinces in 2018. A self-completion questionnaire was completed by students in the classroom setting. ResultsThere were 3774 completed questionnaires: the mean age of respondents was 13.58 (SD 0.87). For traditional bullying, 1332 (35.6%) identified as victims, and 341 (9.5%) as perpetrators. For cyberbullying, 1170 (31.4%) identified as victims, and 622 (16.6%) as perpetrators. After controlling for confounders, risks for traditional victimization were being male, attending boarding school, low academic performance, and a poor relationship with parents. Traditional perpetrators were more likely to be male, and have a poor relationship with parents. Risks for being a victim or perpetrator of cyberbullying were the same: male sex, attending boarding school, and having a poor relationship with parents. Compared to non-victims, traditional victims and cyber victims were at least 1.5 times more likely to report headache and sleep problems; traditional victims were 1.3 times more likely, and cyber victims 1.4 times more likely to report abdominal pain. ConclusionsSchools must take measures to raise awareness of bullying, to identify bullies and victims, and especially to protect the most vulnerable adolescents.

Prevalence, risk factors, and psychosomatic symptoms of bullying in Chinese adolescents in three provinces: a cross-sectional study

BackgroundThe risk factors and effects of bullying are well recognised in many countries, but evidence from China is scarce. This study aimed to investigate the prevalence and risk factors of traditional bullying and cyberbullying in Chinese middle school children (aged 12–15 years) and the psychosomatic symptoms associated with bullying. MethodsA cross-sectional survey using a self-completion questionnaire was done in middle schools in urban and rural Zhejiang, Henan, and Chongqing provinces. In the schools, research assistants introduced the purpose and content of the survey, distributed the questionnaire and stayed in the classroom to respond to any queries. Ethical approval was obtained from the Medical Ethics Committee of Zhejiang University, School of Public Health, Hangzhou, China. FindingsFrom May 20 to Sept 25, 2018, 12 schools in total participated. 3774 questionnaires were completed: the mean age of respondents was 13·58 years (SD 0·87 years). For traditional bullying, 1332 (35·3 % identified as victims, and 341 (9·0% as perpetrators. For cyberbullying, 1170 (31·0%) identified as victims, and 622 (16·5%) as perpetrators. After adjusting for confounders, risk factors for traditional victimisation or perpetration were male sex, rural residence, low academic performance, and a poor relationship with parents. Risk factors for being a victim or perpetrator of cyberbullying were male sex, boarding at school, and a poor relationship with parents. In terms of psychosomatic symptoms, 491 (13·0%) reported they often had headache, 607 (16·1%) abdominal pain, and 597 (15·8%) sleep problems. Traditional victims and cyber victims were more likely to have frequent headaches (adjusted odds ratio 1·3, 95% CI 1·2–1·5 for traditional victims; 1·5, 1·3–1·8 for cyber victims) and frequent abdominal pain (1·2, 1·1–1·4 for traditional victims; 1·3, 1·1–1·5 for cyber victims). Traditional victims (1·3, 1·1–1·5), traditional bullies (1·3, 1·0–1·6), and cyber victims (1·6, 1·4–1·9) were more likely to have frequent sleep problems. InterpretationThe prevalence of bullying among Chinese adolescents is high and it is associated with psychosomatic conditions. Schools must take measures to raise awareness of bullying and to protect the most vulnerable adolescents. FundingGlobal Health Center of Zhejiang University.

A Randomized Noninferiority Trial of Wearing Adjustable Glasses versus Standard and Ready-made Spectacles among Chinese Schoolchildren: Wearability and Evaluation of Adjustable Refraction III

To compare wear of standard, adjustable, and ready-made glasses among children. Randomized, controlled, open-label, noninferiority trial. Students aged 11 to 16 years with presenting visual acuity (VA) ≤6/12 in both eyes, correctable to ≥6/7.5, subjective spherical equivalent refractive error (SER) ≤-1.0 diopters (D), astigmatism and anisometropia both <2.00 D, and no other ocular abnormalities. Participants were randomly allocated (1:1:1) to standard glasses, ready-made glasses, or adjustable glasses based on self-refraction. We recorded glasses wear on twice-weekly covert evaluation by head teachers (primary outcome), self-reported and investigator-observed wear, best-corrected visual acuity (BCVA) (not prespecified), children's satisfaction, and value attributed to glasses. Proportion of glasses wear on twice-weekly covert evaluation by head teachers over 2 months. Among 379 eligible participants, 127 were allocated to standard glasses (mean age, 13.7 years; standard deviation [SD], 1.0 years; 54.3% were male), 125 to ready-made (mean age, 13.6; SD, 0.83; 45.6%), and 127 to adjustable (mean age, 13.4 years; SD, 0.85; 54.3%). Mean wear proportion of adjustable glasses was significantly lower than for standard glasses (45% vs. 58%; P= 0.01), although the adjusted difference (90% confidence interval [CI], -19.0% to -3.0%) did not meet the prespecified inferiority threshold of 20%. Self-reported (90.2% vs. 84.8%, P= 0.64) and investigator-observed (44.1% vs. 33.9%, P= 0.89) wear did not differ between standard and adjustable glasses, nor did satisfaction with (P= 0.97) or value attributed to study glasses (P= 0.55) or increase in quality of life (5.53 [SD, 4.47] vs. 5.68 [SD, 4.34] on a 100-point scale, P > 0.30). Best-corrected visual acuity with adjustable glasses was better (P < 0.001) than with standard glasses. Change in power of study lenses at the end of the study (adjustable: 0.65 D, 95% CI, 0.52-0.79; standard, 0.01 D; 95% CI, -0.006 to 0.03, P < 0.001) was greater for adjustable glasses, although interobserver variation in power measurements may explain this. Lens scratches and frame damage were more common with adjustable glasses, whereas lens breakage was less common than for standard glasses. Proportion of wear was lower with adjustable glasses, although VA was better and measures of satisfaction and quality of life were not inferior to standard glasses.

Urinary bisphenol analogues concentrations and biomarkers of oxidative DNA and RNA damage in Chinese school children in East China: A repeated measures study

The associations between bisphenol analogues (BPs) exposure and oxidative damage was explored in this 3-year longitudinal study of 275 school children in East China. Nine BPs in first morning urine samples were measured to assess BPs exposure, and 8-hydroxydeoxyguanosine (8-OHdG) and 8-oxo-7,8-dihydroguanosine (8-OHG) were measured as biomarkers of oxidative DNA and RNA damage. Linear mixed model (LMM) was used for repeated measures analysis. School children were mainly exposed to BPA, BPS, BPF, and BPAF (detection frequencies: 97.9%, 42.2%, 13.3%, and 12.8%) with median concentrations of 1.55, 0.355, 0.236 and 0.238 μg g−1Cre, respectively. An interquartile range (IQR) increase in urinary BPA was significantly associated with 12.9% (95% CI: 6.1%, 19.6%) increase in 8-OHdG and 19.4% (95% CI: 11.7%, 27.1%) increase in 8-OHG, and for total of BPs (the sum of BPA, BPS, BPF, and BPAF), they were 17.4% (95% CI: 8.9%, 26.0%) for 8-OHdG and 25.9% (95% CI: 16.1%, 35.7%) for 8-OHG, respectively. BPS was positively associated with 8-OHG, but not with 8-OHdG. The study found positive associations of urinary levels of BPA and total BPs with 8-OHdG and 8-OHG and indicated that BPs exposure might cause oxidative RNA damage.

Longitudinal measurement invariance of the Child Problematic Trait Inventory in older Chinese children.

The Child Problematic Traits Inventory (CPTI) is a newly developed informant-rated instrument to measure psychopathic traits during early childhood. The aim of this study was to examine the longitudinal measurement invariance of the CPTI in a group of Chinese schoolchildren. Mothers of 585 children aged 8 to 12 years (50% girls) completed the CPTI twice with one-year interval. Confirmatory factor analyses showed that the CPTI had strict invariance (i.e., equality of factor patterns, loadings, intercepts, and item uniqueness) across time. Furthermore, the internal consistencies for the CPTI subscales were good at both time points and the stability coefficients over time were moderate. Findings suggest that, in children aged 8 to 12 years old, changes in CPTI scores across time can be attributed to actual changes in the child’s psychopathic personality.

Simultaneous Changes in Astigmatism with Noncycloplegia Refraction and Ocular Biometry in Chinese Primary Schoolchildren.

Purpose To assess the changing profile of astigmatism in Chinese schoolchildren and the association between astigmatism changes and ocular biometry. Methods We examined and followed up 1,463 children aged 6–9 years from Wenzhou, China. We measured noncycloplegic refraction twice each year and tested axial length (AL) and corneal radius of curvature (CRC) annually for two years. We defined clinically significant astigmatism (CSA) as ≤−0.75 diopter (D) and non-CSA astigmatism as ≤0 to >−0.75 D. Results Prevalence of CSA at baseline was 22.4% (n = 327) and decreased to 20.3% (n = 297) at the two-year follow-up (P = 0.046). Ninety-two (8.1%) non-CSA children developed CSA. In multiple regression, after adjusting for age, gender, baseline cylinder refraction, and axis, children who had longer baseline ALs (>23.58 mm; odds ratio (OR) = 5.19, 95% confidence interval (CI): 2.72–9.90) and longer baseline AL/CRC ratio (>2.99, OR = 4.99, 95% CI: 2.37–10.51) were more likely to develop CSA after two years. Four-hundred and two (27.5%) children had increased astigmatism, 783 (53.5%) had decreased, and 278 (19.0%) had no change during the two-year follow-up. Children with increased astigmatism had longer baseline ALs (23.33 mm, P < 0.001), higher AL/CRC ratios (2.99 mm, P < 0.001), and more negative spherical equivalent refraction (SER) (−0.63 D, P < 0.001) compared with the decreased and no astigmatism change subgroups. Also, children in the increased astigmatism subgroup had more AL growth (0.68 mm, P < 0.001), higher increases in AL/CRC ratio (0.08, P < 0.001), and more negative SER change (−0.86 D, P < 0.001) compared with the decreased and no astigmatism change subgroups. Conclusions The prevalence of astigmatism decreased slightly over the two-year study period. Longer ALs and higher AL/CRC ratios were independent risk factors for developing CSA. Increased astigmatism was associated with AL growth, AL/CRC ratio increases, and the development of myopia. This trial is registered with ChiCTR1800019915.

Association of Active Commuting with Sport Time and Outdoor Play Time in Chinese Schoolchildren

PURPOSE: Active commuting has been proved to be related to higher levels of physical activity in children in Western countries. Whether this relationship exists for specific forms of physical activity, e.g., sport participation and outdoor play, remains unclear, especially among Chinese children. This study aimed to investigate the association of active commuting with sport time and outdoor play time in Chinese schoolchildren. METHODS: A total of 441 children (49.7% boys, mean age = 8.3 ± 0.9 years) in grades 1 to 3 from four primary schools in Beijing participated in this study. Information of children's walking trips, daily sport time, and daily outdoor play time was reported by parents using the modified Chinese version of the children's leisure activities study survey. Children were categorized as either active (≥ 6 walking trips per week) or passive commuters (< 6 walking trips per week) based on the parent-reported number of trips walking to and from school. Children reported their own sex, age, and exercise self-efficacy. Children's body weight and height were measured by researchers to calculate body mass index (BMI). Differences of daily sport time and outdoor play time between active vs. passive commuters were examined by the analysis of covariance (ANCOVA) adjusting for children's age, BMI, and exercise self-efficacy. ANCOVA were conducted separately for boys and girls. RESULTS: 42.7% of boys and 40.3% of girls were classified as active commuters. In boys, no difference was found for daily sport time between active and passive commuters (62.0 ± 46.7 min/d vs. 55.4 ± 41.4 min/d, P = 0.266), whereas active commuters had more time of outdoor play than passive commuters (194.8 ± 122.4 min/d vs. 153.7 ± 122.3 min/d, P = 0.041). For girls, neither daily sport time (64.1 ± 37.7 min/d vs. 54.1 ± 43.9 min/d, P = 0.110) nor daily outdoor play time (146.3 ± 129.6 min/d vs. 178.5 ± 141.4 min/d, P = 0.156) differed between active and passive commuters. CONCLUSIONS: Boys who actively commute to school have higher levels of outdoor play time. Promoting active commuting may increase levels of physical activity in Chinese schoolchildren.

Comparisons Of In-school And Out-of-school Physical Activity Among Chinese Elementary School Children

PURPOSE: Relatively little is known regarding children’s physical activity (PA) during school and outside of school. Therefore, the objective of this study was to compare in-school and out-of-school PA among Chinese elementary school children. METHODS: A cross-sectional study was conducted among 360 (4th grade) children recruited from 3 elementary schools in Shanghai, China. PA was measured in 5 consecutive school days by accelerometers. Minutes per hour (min/h) of moderate-to-vigorous PA (MVPA) and total PA (TPA) were calculated using established cut points. Children’s in-school and out-of-school MVPA and TPA were compared using paired t test. Gender differences in MVPA and TPA across the two study settings were also examined using independent t test. RESULTS: 242 participants (boys: 45.5%, mean age: 9.6±0.3 years, weight:35.0±7.6 kg, height:139.8±6.1 cm, body mass index: 17.8±2.9 kg/m2) provided valid accelerometer data (defined as ≥ 2 days, ≥10 h/day) and were included in the study. Results showed a higher level of in-school MVPA compared to out-of-school MVPA (3.1 min/h vs 2.3 min/h, P<0.001) and of in-school TPA compared to out-of-school TPA (17.3 min/h vs 15.1 min/h, P<0.001). There were no difference in out-of-school MVPA and TPA across gender but boys showed a higher level of in-school MVPA (3.1 min/h vs 2.3 min/h, P<0.001) and TPA (18.3 min/h vs 16.6 min/h, P<0.001) compared to girls. CONLUSION: Chinese elementary school children spent more time engaging in in-school PA compared to out-of-school PA with boys showing a higher level of in-school PA compared to their counterpart girls. Findings suggest that PA promotion strategies should focus on developing out of school, community-based programs and that maximizing in-school PA among girls.

Breakfast Types Are Associated with Adolescents’ IQ and Academic Achievement (P18-103-19)

ObjectivesResearch has documented that frequent breakfast consumption is associated with better cognition. However, the relationship between breakfast type and cognitive functioning is lesser known. In this study, we examined both breakfast type and consumption frequency in relation to IQ and academic achievement in a sample of 12-year-old Chinese schoolchildren. MethodsParticipants included 835 12-year-old children from the China Jintan Cohort Study. Breakfast habits, food types, and intake frequency were assessed through self-administered nutrition questionnaires. The types of foods measured included fruits/vegetables, grain/rice, meat/egg, dairy products, and soy products. IQ was measured with the Chinese version of the Wechsler Intelligence Scale for Children. Standardized academic achievement was collected through school reports. Multivariate general linear modeling was implemented for data analysis. ResultsMore frequent breakfast consumption of grain/rice and meat/egg (6–7 days per week) was significantly associated with higher verbal, performance, and full scale IQs, by 3.562, 3.687, and 4.559 points, respectively (all P < 0.05), compared with rare grain/rice intake (0–2 days per week). Regular meat/egg breakfast consumption appeared to facilitate academic achievement (6–7 vs. 0–2 d/w, mean difference = 0.232, P = 0.043). Interestingly, frequent consumption of fruit/vegetables and dairy products did not affect cognitive functioning. Furthermore, an intermediate frequency (3–5 d/w) showed better verbal IQ and academic achievement. A dose-response relationship showed that even after adjustment for up to nine covariates, those who ate breakfast 6–7 days per week tended to have a higher verbal IQ score of 6.760 (P = 0.017) and a higher average academic achievement score of 0.831 (P < 0.001), than those who rarely ate breakfast (0–2 d/w). ConclusionsOur study shows that frequent consumption of grain/rice and meat/egg for breakfast may have positive associations with cognitive functioning in adolescents. Nevertheless, inference cannot be drawn from this cross-sectional analysis. Future studies should assess the long-term effects of breakfast type on cognitive abilities. Funding SourcesNational Institute of Environmental Health Sciences/National Institutes of Health (R01-ES-01,8858, K02-ES-01,9878, and K01-ES015877).

Association of Visual Impairment With Economic Development Among Chinese Schoolchildren

Few studies have reported the association of economic growth with trends of visual impairment in schoolchildren in China or elsewhere. To describe 30-year trends and patterns in visual impairment in China and to explore the association between visual impairment and economic development. In this time series analysis of 7 successive cross-sectional surveys from 1985 to 2014, a total of 1 951 084 schoolchildren aged 7 to 18 years from all provinces and autonomous regions of mainland China, excluding Tibet, were studied. In 1985, the survey was conducted between March to June; In 1991-2014, the surveys were conducted between September and November. Data analysis was performed from April 1, 2018, to January 31, 2019. The province-level gross domestic product (GDP) per capita was extracted from the China Statistical Yearbook. Visual impairment, defined as unaided distance visual acuity of worse than 6/7.5 (20/25 Snellen equivalent), and moderate to severe visual impairment, defined as unaided distance visual acuity of worse than 6/18 (20/63 Snellen equivalent), in the worse eye. A total of 1 951 084 participants (mean [SD] age, 12.6 [3.4] years; 50.5% male) were included in the analysis. Among students aged 7 to 18 years, the prevalence of visual impairment increased from 23.7% (95% CI, 23.6%-23.8%) in 1985 to 35.1% (95% CI, 34.9%-35.3%) in 1995 to 55.0% (95% CI, 54.8%-55.3%) in 2014. In 2014, the prevalence was higher among girls (58.3%; 95% CI, 54.8%-55.3%) vs boys (51.8%; 95% CI, 51.5%-52.1%) (prevalence ratio [PR] girls vs boys, 1.12; 95% CI, 1.11-1.13) and among students living in urban (59.9%; 95% CI, 59.6%-60.2%) vs rural (50.2%; 95% CI, 49.9%-50.5%) areas (PR urban vs rural, 1.17; 95% CI, 1.16-1.18), although a more rapid relative increase in prevalence occurred in rural areas (15.3% in 1985 to 50.2% in 2014) than in urban areas (31.5% in 1985 to 59.9% in 2014). From 1995 to 2014, the GDP in China increased from $1263 to $7594 (in 2014 US$ constant price). After demographic characteristics (cluster effect of school, age, sex, urban vs rural location, and relative socioeconomic status within province) were adjusted for, the regression model revealed that every 100% increase in GDP was associated with a 20% (PR, 1.20; 95% CI, 1.20-1.21) increase in the relative risk of visual impairment and a 27% (PR, 1.27; 95% CI, 1.26-1.27) increase in the relative risk of moderate to severe visual impairment. The association was stronger in male (PR, 1.22; 95% CI, 1.21-1.23 for male [as reference] vs 1.19; 95% CI, 1.18-1.19 for female; P < .001), rural (PR, 1.32; 95% CI, 1.31-1.33 for rural [as reference] vs 1.12; 95% CI, 1.12,-1.33 for urban; P < .001), and younger age groups (PR, 1.27; 95% CI, 1.24-1.29 for 7-9 years of age [as reference] vs 1.34; 95% CI, 1.32-1.36 for 10-12 years of age; P < .001; 1.21; 95% CI, 1.20-1.22 for 13-15 years of age; P < .001; and 1.12; 95% CI, 1.11,-1.13 for 16-18 years of age; P < .001). The rapid increase of visual impairment prevalence and the association between GDP and visual impairment over time suggest that further exacerbation of childhood visual impairment may occur as economic development continues in China.