Physical Fitness and Body Mass Index Status of Hong Kong Primary Schoolchildren across the COVID-19 Pandemic, before and after School Closure.

OBJECTIVE: To determine whether health-related physical fitness and body mass index (BMI) status differed before and after school closure from the COVID-19 pandemic in a population-based cohort of Hong Kong primary schoolchildren. STUDY DESIGN: We examined the BMI z score, BMI status, and physical fitness z scores including (i) upper limb muscle strength, (ii) 1-minute sit-up test, (iii) sit-and-reach test, and (iv) endurance run tests, among 3 epochs: prepandemic (September 2018-August 2019), before school closure (September 2019-January 2020), and partial school reopening (September 2021-August 2022), using a repeated cross-sectional approach. RESULTS: A total of 137 752 primary schoolchildren aged 6-12 years were recruited over 3 academic years. Obesity increased significantly from 25.9% in 2018/19 to 31.0% in 2021/22, while underweight increased slightly from 6.1% to 6.5%. All tested parameters were adversely affected by the pandemic. The negative trend over time was far more pronounced in all 4 physical fitness scores in the underweight group, although performance in handgrip strength had no significance between 2018/19 and 2021/22. CONCLUSIONS: Schoolchildren who are both underweight and overweight/obese are vulnerable to adverse changes in physical fitness during the COVID-19 pandemic. To eliminate the negative health and fitness outcomes, it is urgent to develop strategies for assisting schoolchildren in achieving a healthy weight, especially in the postpandemic era.

Positive parent-child interactions moderate certain maltreatment effects on psychosocial well-being in 6-year-old children.

BACKGROUND: Positive parental interactions may buffer maltreated children from poor psychosocial outcomes. The study aims to evaluate the associations between various types of maltreatment and psychosocial outcomes in early childhood, and examine the moderating effect of positive parent-child interactions on them. METHODS: Data were from a representative Chinese 6-year-old children sample (n = 17,088). Caregivers reported the history of child maltreatment perpetrated by any individuals, completed the Strengths and Difficulties Questionnaire as a proxy for psychosocial well-being, and reported the frequency of their interactions with children by the Chinese Parent-Child Interaction Scale. RESULTS: Physical abuse, emotional abuse, neglect, and sexual abuse were all associated with higher odds of psychosocial problems (aOR = 1.90 [95% CI: 1.57-2.29], aOR = 1.92 [95% CI: 1.75-2.10], aOR = 1.64 [95% CI: 1.17-2.30], aOR = 2.03 [95% CI: 1.30-3.17]). Positive parent-child interactions were associated with lower odds of psychosocial problems after accounting for different types of maltreatment. The moderating effect of frequent parent-child interactions was found only in the association between occasional only physical abuse and psychosocial outcomes (interaction term: aOR = 0.34, 95% CI: 0.15-0.77). CONCLUSIONS: Maltreatment and positive parent-child interactions have impacts on psychosocial well-being in early childhood. Positive parent-child interactions could only buffer the adverse effect of occasional physical abuse on psychosocial outcomes. More frequent parent-child interactions may be an important intervention opportunity among some children. IMPACT: It provides the first data on the prevalence of different single types and combinations of maltreatment in early childhood in Shanghai, China by drawing on a city-level population-representative sample. It adds to evidence that different forms and degrees of maltreatment were all associated with a higher risk of psychosocial problems in early childhood. Among them, sexual abuse posed the highest risk, followed by emotional abuse. It innovatively found that higher frequencies of parent-child interactions may provide buffering effects only to children who are exposed to occasional physical abuse. It provides a potential intervention opportunity, especially for physically abused children.

Effects of firsthand tobacco smoking on retinal vessel caliber: a systematic review and meta-analysis.

PURPOSE: To review the effects of firsthand tobacco smoking on central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) of firsthand tobacco smokers. METHODS: We performed a search on EMBASE and PubMed for studies up to 15th July 2022. Two independent reviewers selected studies with baseline data of CRAE and CRVE of current smokers, nonsmokers, and former smokers. Initial search identified 893 studies, of which 10 were included in the meta-analysis. Two independent reviewers extracted data from the included studies. The quality of studies was assessed by the Newcastle-Ottawa Scale. RESULTS: In this meta-analysis, 7431 nonsmokers, 2448 current smokers and 5786 former smokers, as well as 7404 nonsmokers, 2430 current smokers and 5763 former smokers were included in CRAE and CRVE analysis respectively. Nonsmokers had narrower CRVE (Weighted mean difference [WMD], -12.15; 95% CI, -17.33 - -6.96) and CRAE (WMD, -4.77; 95% CI, -7.96 - -1.57) than current smokers, and narrower CRVE (WMD, -3.08; 95% CI, -6.06 - -0.11) than former smokers. Current smokers had wider CRVE (WMD, 10.42; 95% CI, 7.80 - 13.04) and CRAE (WMD, 7.05; 95% CI, 6.65 - 7.46) than former smokers. Subgroup analysis and sensitivity analysis were performed. CONCLUSION: Firsthand tobacco smoking resulted in wider CRAE and CRVE in current and former smokers, particularly in CRVE, and such changes may not be reversible after smoking cessation. Therefore, retinal vessel caliber may reflect the effects of firsthand tobacco smoking and be used to estimate the risk of cardiovascular diseases.

Changes in, and factors associated with family functioning: results of four cross-sectional household surveys from 2011 to 2017 in Hong Kong.

BACKGROUND: Previous research has well-documented that family functioning is an important predictor of individuals' physical and mental health. However, relatively little research has explored family functioning at the family and population levels, such as changes in family functioning across years and whether predictors of family functioning differ across different family structures. Understanding of the changes in family functioning across years and factors promoting family functioning will inform the development of preventive measures to enhance family health and resilience. Objectives of the study were: (1) to examine the changes in family functioning across a 6-year study period and (2) to study protective factors associated with family functioning and the extent to which the factors are the same or different across different family structures. METHOD: The study involved secondary data analysis of the biannual Family Survey carried out by the Family Council, an advisory body to the Hong Kong government. A series of ANOVA and regression analyses were conducted using data of four population-based cross-sectional household surveys conducted in Hong Kong in 2011, 2013, 2015, and 2017. RESULTS: There were some fluctuations in overall family functioning scores across the study period, but no significant difference was found between the scores in 2011 and 2017. Different predictors of family functioning were found for different family types, and frequent family communication was a common protective factor for most family types, including never married, married/cohabiting with children, and married/cohabiting with no children. CONCLUSION: The study is among the first to examine changes in family functioning at the population level. Monitoring and addressing family functioning may help tackle various social problems and future public health crises. Interventions to promote family functioning should address both common and different protective factors of different family types.

Effect of a Mobile Game-Based Intervention to Enhance Child Safety: Randomized Controlled Trial.

BACKGROUND: Evidence supports the effectiveness of serious games in health education, but little is known about their effects on the psychosocial well-being of children in the general population. OBJECTIVE: This study aimed to investigate the potential of a mobile game-based safety education program in improving children's safety and psychosocial outcomes. METHODS: Safe City is a mobile roleplaying game specifically designed to educate children in Hong Kong about safety. This randomized controlled trial included 340 children in grades 4 through 6. Intervention arm participants (n=170) were instructed to play the Safe City mobile game for 4 weeks, whereas control arm participants (n=170) received a safety booklet. All participants completed a survey on safety knowledge and behaviors and psychosocial problems at baseline (T1), 1 month postintervention (T2), and 3 months postintervention (T3). Cumulative game scores and mini-game performance were analyzed as a proxy for the extent of exposure to the game. Outcome data were analyzed using 2-sample 2-tailed t tests to compare mean change from T1 to T2 and to T3 for intervention versus control arm participants. The association of game use with outcome changes postintervention was analyzed using generalized additive models. RESULTS: No significant differences were found in mean changes between the intervention and control arms. However, use analyses showed that higher game scores were associated with improvements in safe behavior (P=.03) and internalizing problems (P=.01) at T3. Matching and Spot the Danger mini-game performance significantly predicted improvements in safety knowledge at T2 and T3. CONCLUSIONS: Analysis of use has shown that playing the Safe City mobile game can result in significant improvements in safety knowledge and reductions in unsafe behavior and internalizing problems. These findings provide evidence for the positive impact of serious games on psychological and social well-being, highlighting the potential of technology-driven interventions to assist children in learning about safety and preventing injuries. TRIAL REGISTRATION: ClinicalTrials.org NCT04096196; https://clinicaltrials.gov/show/NCT04096196. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/17756.

Building a baby-friendly community: Development, strategy, implementation and evaluation of a BFCI program.

AIM: The aim of the study was to investigate the impact of the use of baby-friendly community initiative (BFCI) model on various stakeholders in the community. DESIGN: Quasi-experimental research design. METHOD: The study was conducted in public premises and online workshops from April 2019 to September 2022. Participants were followed up for a period of 1 month, except for those employed at public premises. The program involved training based on an accredited BFCI framework to cultivate a breastfeeding-friendly attitude and knowledge. A paired sample t-test was used to examine breastfeeding attitude and knowledge scores before and after BFCI training among staff employed from public premises. An analysis of variance was conducted to examine the breastfeeding self-efficacy and attitude scores, measured repeatedly at different timepoints over 1-month timepoint (T0, T1 and T2) among pregnant and postpartum women. RESULTS: A total of 2340 perinatal women and 1339 staff from public premises were recruited. For staff, there was an increase in the mean score of breastfeeding knowledge and attitude by 5.8 and 6.1, respectively, at T1. Similarly, for perinatal women, there was an increase in the mean score of breastfeeding self-efficacy and attitude by 6.6 and 3.3, respectively, at T1. CONCLUSION: In summary, a BFCI model, with active community participation, accreditation and an award system, has been effective in promoting breastfeeding. Adapting the baby-friendly hospital initiative to local contexts and employing a social theory model can enhance breastfeeding promotion and improve infant health outcomes. Prioritizing culturally sensitive breastfeeding education is crucial for successful BFCI implementation. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Healthcare professionals should consider clients' culture and socio-economic backgrounds when providing breastfeeding education to maximize effectiveness. The target audience for breastfeeding education should be expanded to include various community stakeholders beyond families. IMPACT: What problem did the study address? This study addressed the problem of knowledge gaps among stakeholders in building a breastfeeding-friendly community, particularly in implementing a baby-friendly community initiative (BFCI) as part of a baby-friendly hospital initiative (BFHI). The research filled a service gap by providing effective interventions targeting community stakeholders and assessing the impact of a BFCI program on their knowledge and attitudes towards breastfeeding. What were the main findings? The findings highlighted the effectiveness of a BFCI program in enhancing breastfeeding knowledge and attitudes among frontline staff and increasing breastfeeding confidence among mothers. These findings contribute to the understanding of the program's impact on different stakeholders in the community. Where and on whom will the research have an impact? It impacts on global policymakers by providing insights for developing comprehensive guidelines for future BFCI implementations. It also contributes to the creation of a more baby-friendly community, benefiting breastfeeding families and their infants by promoting and supporting breastfeeding families. REPORTING METHOD: This study has adhered to relevant EQUATOR guidelines using the TREND reporting guideline. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution. WHAT DOES THIS PAPER CONTRIBUTE TO THE WIDER GLOBAL CLINICAL COMMUNITY?: This study provides an overview of the establishment of a localized BFCI program. It also opens up a new direction for the community to investigate BFCI strategies for community stakeholders. It also provides evidence to support other countries in following a similar process, as each country approaches becoming breastfeeding-friendly in its own unique way. TRIAL AND PROTOCOL REGISTRATION: No protocol.

Early-life family and school impacts on adolescent conduct problems: A path analysis.

Limited research has been conducted to examine the factors during early childhood that may contribute to conduct problems in later stages of life. This study aimed to investigate the relationship between family and school environments during early childhood and conduct problems in adolescence. In Wave 1 (W1), the study recruited 502 participants, aged 5-6 years, from Hong Kong local kindergartens, with 51.4% boys. One of their parents provided information about family socioeconomic status (SES), parent-child recreational activities, and child screen time, whereas the class teacher rated their school readiness using the Chinese version of the Early Development Instrument. Data on the number of special facilities were obtained from the kindergartens. In Wave 2 (W2), the same parents of 395 participants were asked about their involvement in their children's education. Finally, in Wave 3 (W3), the parents of 206 participants completed the Conduct Problem scale of the Strength and Difficulties Questionnaire to evaluate the level of conduct problems in the participants. The results of the path analysis revealed that higher W1 family SES was associated with fewer W3 conduct problems through an increase in W1 and W2 parental involvement in children's learning and play activities. Findings have implications for understanding the impact of early-life family and school environments on adolescent conduct problems. Early childhood interventions that promote family resources and positive parent-child interactions have the potential to reduce adolescent conduct problems.

Clinical characteristics of unvaccinated or incompletely vaccinated children with neurological manifestations due to SARS-CoV-2 Omicron infection.

Omicron generally causes milder disease than previous strains of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), especially in fully vaccinated individuals. However, incompletely vaccinated children may develop Omicron-related complications such as those affecting the central nervous system. To characterize the spectrum of clinical manifestations of neuro-COVID and to identify potential biomarkers associated with clinical outcomes, we recruited 15 children hospitalized for Omicron-related neurological manifestations in three hospitals in Hong Kong (9 boys and 6 girls aged 1-13 years). All were unvaccinated or incompletely vaccinated. Fourteen (93.3%) were admitted for convulsion, including benign febrile seizure (n = 7), complex febrile seizure (n = 2), seizure with fever (n = 3), and recurrent breakthrough seizure (n = 2), and the remaining nonconvulsive patient developed encephalopathic state with impaired consciousness. None of the seven children with benign febrile seizure and six of eight children with other neurological manifestations had residual deficits at 9-month follow-up. SARS-CoV-2 RNA was undetectable in the cerebrospinal fluid (CSF) specimens of seven patients who underwent lumbar puncture. Spike-and-wave/sharp waves affecting the frontal lobes were detected in four of seven (57.1%) patients who underwent electroencephalogram. Children with Omicron-related neurological manifestations had significantly higher blood levels of IL-6 (p < 0.001) and CHI3L1 (p = 0.022) than healthy controls, and higher CSF levels of IL-6 (p = 0.002) than children with non-COVID-19-related febrile illnesses. Higher CSF-to-blood ratios of IL-8 and CHI3L1 were associated with longer length of stay, whereas higher ratios of IL-6 and IL-8 were associated with higher blood tau level. The role of CSF:blood ratio of IL-6, IL-8, and CHI3L1 as prognostic markers for neuro-COVID should be further evaluated.

Child maltreatment and telomere length in middle and older age: retrospective cohort study of 141 748 UK Biobank participants.

BACKGROUND: There is evidence that child maltreatment is associated with shorter telomere length in early life. AIMS: This study aims to examine if child maltreatment is associated with telomere length in middle- and older-age adults. METHOD: This was a retrospective cohort study of 141 748 UK Biobank participants aged 37-73 years at recruitment. Leukocyte telomere length was measured with quantitative polymerase chain reaction, and log-transformed and scaled to have unit standard deviation. Child maltreatment was recalled by participants. Linear regression was used to analyse the association. RESULTS: After adjusting for sociodemographic characteristics, participants with three or more types of maltreatment presented with the shortest telomere lengths (ß = -0.05, 95% CI -0.07 to -0.03; P < 0.0001), followed by those with two types of maltreatment (ß = -0.02, 95% CI -0.04 to 0.00; P = 0.02), referent to those who had none. When adjusted for depression and post-traumatic stress disorder, the telomere lengths of participants with three or more types of maltreatment were still shorter (ß = -0.04, 95% CI -0.07 to -0.02; P = 0.0008). The telomere lengths of those with one type of maltreatment were not significantly different from those who had none. When mutually adjusted, physical abuse (ß = -0.05, 95% CI -0.07 to -0.03; P < 0.0001) and sexual abuse (ß = -0.02, 95% CI -0.04 to 0.00; P = 0.02) were independently associated with shorter telomere length. CONCLUSIONS: Our findings showed that child maltreatment is associated with shorter telomere length in middle- and older-aged adults, independent of sociodemographic and mental health factors.

Treatment with methylphenidate and the risk of fractures among children and young people: A systematic review and self-controlled case series study.

AIMS: Animal studies suggest that methylphenidate treatment for around 3 months may lead to less mineralized and weaker appendicular bones. A systematic review was conducted to summarize the evidence from observational studies, and a self-controlled case series study was used to compare the risk before and after treatment initiation. METHODS: Literature search was conducted using PubMed, Embase and the Cochrane Library to identify observational studies on methylphenidate and fractures. We also conducted a self-controlled case series study with individuals aged 5-24 years who received methylphenidate treatment and experienced fractures from 2001 to 2020 in Hong Kong. Incidence rate ratios and 95% confidence intervals were calculated by comparing the incidence rate in the methylphenidate-exposed period compared with nonexposed period. RESULTS: Six cohort studies and 2 case-control studies were included in the systematic review. For all-cause fractures, studies found a 39-74% lower risk in treated-attention deficit hyperactivity disorder (ADHD) group compared with untreated ADHD but no difference between stimulants and nonstimulants. Differences between sexes and treatment duration were also found-significant results were shown in males and those with longer treatment duration. Among 43 841 individuals with ADHD medication before the year 2020, 2023 were included in the self-controlled case series analysis. The risks of fractures were lower by 32-41% in different treatment periods when compared with 6 months before treatment initiation. CONCLUSION: Methylphenidate treatment may lower the risk of all-cause fractures from both study designs; however, further evidence is needed about the treatment duration and sex effect. Conclusions on stress fractures are not yet established, and further research is required.

Maternal Benzodiazepines and Z-Drugs Use during Pregnancy and Adverse Birth and Neurodevelopmental Outcomes in Offspring: A Population-Based Cohort Study.

INTRODUCTION: The use of benzodiazepines and/or z-drugs in women of childbearing age has increased. OBJECTIVE: The aim of the study was to evaluate whether gestational benzodiazepine and/or z-drug exposure is associated with adverse birth and neurodevelopmental outcomes. METHODS: A population-based cohort including mother-child pairs from 2001 to 2018 in Hong Kong was analysed to compare gestationally exposed and nonexposed children on the risk of preterm birth, small for gestational age, autism spectrum disorder (ASD), and attention-deficit/hyperactivity disorder (ADHD) through logistic/Cox proportional hazards regression with a 95% confidence interval (CI). Sibling-matched analyses and negative control analyses were applied. RESULTS: When comparing gestationally exposed with gestationally nonexposed children, the weighted odds ratio (wOR) was 1.10 (95% CI = 0.97-1.25) for preterm birth and 1.03 (95% CI = 0.76-1.39) for small for gestational age, while the weighted hazard ratio (wHR) was 1.40 (95% CI = 1.13-1.73) for ASD and 1.15 (95% CI = 0.94-1.40) for ADHD. Sibling-matched analyses showed no association between gestationally exposed children and their gestationally nonexposed siblings for all outcomes (preterm birth: wOR = 0.84, 95% CI = 0.66-1.06; small for gestational age: wOR = 1.02, 95% CI = 0.50-2.09; ASD: wHR = 1.10, 95% CI = 0.70-1.72; ADHD: wHR = 1.04, 95% CI = 0.57-1.90). Similarly, no significant differences were observed when comparing children whose mothers took benzodiazepines and/or z-drugs during pregnancy to children whose mothers took benzodiazepines and/or z-drugs before but not during pregnancy for all outcomes. CONCLUSIONS: The findings do not support a causal relationship between gestational benzodiazepines and/or z-drugs exposure and preterm birth, small for gestational age, ASD, or ADHD. Clinicians and pregnant women should carefully balance the known risks of benzodiazepines and/or z-drugs use against those of untreated anxiety and sleep problems.

Preterm postnatal complications and risk of attention-deficit/hyperactivity disorder.

AIM: To investigate the association between the risk of attention-deficit/hyperactivity disorder (ADHD) and preterm birth and determine how postnatal complications in children born preterm is associated with the risk of ADHD. METHOD: This population-based cohort study used data from the Hong Kong electronic medical records. We followed 359 614 children (48% female; 6-17 years old, mean 11 years 7 months, SD 3 years 2 months) born in public hospitals in Hong Kong from 1st January 2004 to 31st December 2014 and collected medical records and demographic details for mothers and children until 11th November 2020. RESULTS: The risk of ADHD was 4.0% in children born at term and 5.1% in children born preterm. The odds ratio for ADHD was 2.08 (95% confidence interval [CI] 1.64-2.64) for children born extremely preterm, 1.64 (95% CI 1.46-1.85) for children born very preterm, and 1.15 (95% CI 1.08-1.23) for children born late preterm. Among preterm postnatal complications, only early respiratory disease, retinopathy of prematurity (ROP), and intraventricular haemorrhage were significant predictors of ADHD after controlling for preterm birth, other risk factors, and sociodemographic variables. The excess risk of ADHD among children born very preterm or late preterm could be partly explained by respiratory disease. ROP partially mediated the risk of ADHD in children born very preterm. INTERPRETATION: Children born preterm in all subcategories, from extremely preterm to late preterm, have increased risk of ADHD. Early respiratory infection partially mediates the risk of ADHD in children born preterm.

Motivation, injury prevention, and the incidence of sports injuries: A three-wave longitudinal test of self-determination theory.

This study applied self-determination theory (SDT) as a psychological framework to examine whether psychological need support and autonomous motivation are predictive of sports injury preventive behaviors and the incidence of sports injuries. 2042 secondary school students (mean age = 14.33, male = 44.3%) from China completed a survey of the study variables (using established scales) at three time points (baseline, 1-month follow-up, 3-month follow-up). Structural equation modeling examined the core tenets of SDT by testing if the change-scores of the SDT variables (i.e., psychological need support from PE teachers, students' motivation, and students' behavioral adherence) between baseline and 1-month follow-up, were predictive of sports injury incidence assessed at 3-month follow-up. Our model demonstrated acceptable goodness-of-fit parameters (CFI = 0.97, TLI = 0.96, RMSEA = 0.03, and SRMR = 0.05). The relationships between psychological need support, autonomous motivation, and behavioral adherence were both positive and significant. These SDT variables predicted the future incidence of sports injuries following the motivational pathways of SDT. Our study provides evidence of the predictive power of SDT variables on sports injury preventive behaviors and the incidence of sports injuries: Students who perceive their PE teachers as psychological need supportive possess higher autonomous motivation and behavioral adherence towards sports injury prevention, and are also less likely to encounter sports injuries in the future.

Carditis After COVID-19 Vaccination With a Messenger RNA Vaccine and an Inactivated Virus Vaccine : A Case-Control Study.

BACKGROUND: Case reports of carditis after BNT162b2 vaccination are accruing worldwide. OBJECTIVE: To examine the association of BNT162b2 and CoronaVac (Sinovac) vaccination with carditis. DESIGN: Case-control study with hospital control participants. SETTING: Territory-wide, public health care database with linkage to population-based vaccination records in Hong Kong. PATIENTS: Inpatients aged 12 years or older first diagnosed with carditis were selected as case patients. All other hospitalized patients without carditis were treated as control participants. Ten control participants were randomly matched with each case patient by age, sex, and admission date. INTERVENTION: Vaccination with BNT162b2 or CoronaVac. MEASUREMENTS: Incident diagnosis of carditis based on the International Classification of Diseases, Ninth Revision, and elevated troponin levels. RESULTS: A total of 160 case patients and 1533 control participants were included. Incidence of carditis per 100 000 doses of CoronaVac and BNT162b2 administered was estimated to be 0.31 (95% CI, 0.13 to 0.66) and 0.57 (CI, 0.36 to 0.90), respectively. Multivariable analyses showed that recipients of the BNT162b2 vaccine had higher odds of carditis (adjusted odds ratio [OR], 3.57 [CI, 1.93 to 6.60]) than unvaccinated persons. Stratified by sex, the OR was 4.68 (CI, 2.25 to 9.71) for males and 2.22 (CI, 0.57 to 8.69) for females receiving the BNT162b2 vaccine. The ORs for adults and adolescents receiving the BNT162b2 vaccine were 2.41 (CI, 1.18 to 4.90) and 13.79 (CI, 2.86 to 110.38), respectively. Subanalysis showed an OR of 9.29 (CI, 3.94 to 21.91) for myocarditis and 1.06 (CI, 0.35 to 3.22) for pericarditis associated with BNT162b2. The risk was mainly seen after the second dose of BNT162b2 rather than the first. No association between CoronaVac and carditis with a magnitude similar to that for BNT162b2 was seen. LIMITATION: Limited sample size, absence of electrocardiography and other clinical investigative data, and unrecorded overseas vaccination exposure. CONCLUSION: Despite a low absolute risk, there is an increased risk for carditis associated with BNT162b2 vaccination. This elevated risk should be weighed against the benefits of vaccination. PRIMARY FUNDING SOURCE: Health and Medical Research Fund.

Effectiveness of Facebook Groups and Pages on Participant Recruitment Into a Randomized Controlled Trial During the COVID-19 Pandemic: Descriptive Study.

BACKGROUND: In response to the unprecedented challenges posed by the COVID-19 pandemic, conventional recruitment approaches were halted, causing the suspension of numerous clinical trials. Previously, Facebook (Meta Platforms, Inc) has emerged as a promising tool for augmenting participant recruitment. While previous research has explored the use of Facebook for surveys and qualitative studies, its potential for recruiting participants into randomized controlled trials (RCTs) remains underexplored. OBJECTIVE: This study aimed to comprehensively examine the effectiveness of using Facebook groups and pages to facilitate participant recruitment during the COVID-19 pandemic for an RCT on the effectiveness of a remote parenting program, 1-2-3 Magic, in families who have children with attention-deficit/hyperactivity disorder (ADHD) in the United Kingdom. METHODS: We disseminated 5 Facebook posts with an attached digital flyer across 4 prominent ADHD UK support groups and pages run by the National Attention Deficit Disorder Information and Support Services, reaching an audience of around 16,000 individuals over 2 months (January 7 to March 4, 2022). Eligibility criteria mandated participants to be parents or caregivers of a child with diagnosed ADHD aged 12 years or younger, be residing in the United Kingdom, have access to stable internet, and have a device with the Zoom (Zoom Video Communications) app. Participants were required to have never attended 1-2-3 Magic training previously. Prospective participants expressed their interest through Microsoft Forms (Microsoft Corporation). The trial aimed to recruit 84 parents. It is important to note that the term "parent" or "caregiver" in the RCT and in this study within a trial refers to anybody who has legal responsibility for the child. RESULTS: Overall, 478 individuals registered their interest through Microsoft Forms within the stipulated 2-month window. After the eligibility check, 135 participants were contacted for a baseline meeting through Zoom. The first 84 participants who attended a baseline meeting and returned a completed consent form were enrolled. Subsequently, another 16 participants were added, resulting in a final sample of 100 participants. This recruitment strategy incurred negligible expenses and demanded minimal human resources. The approach yielded favorable outcomes by efficiently attracting eligible participants in a condensed time frame, transcending geographical barriers throughout the United Kingdom, which would have been tedious to achieve through traditional recruitment methods. CONCLUSIONS: Our experience demonstrated that digital flyers posted in the targeted Facebook groups were a cost-effective and quick method for recruiting for an RCT, which opened during the COVID-19 pandemic when lockdown restrictions were in place in the United Kingdom. Trialists should consider this low-cost recruitment intervention for trials going forward, and in the case of a global pandemic, this novel recruitment method enabled the trial to continue where many have failed. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN) 15281572; https://www.isrctn.com/ISRCTN15281572.

Natural history of infants with vitamin D deficiency in Hong Kong.

BACKGROUND AND OBJECTIVES: The usual recommended intake of vitamin D for healthy infants is 400 international unit (IU) daily. However, a high dose of vitamin D at 2000-3000 IU daily is needed for those with vitamin D deficiency (VDD). This study aimed to assess the natural history of a group of healthy infants with VDD and the associated factors for persistent VDD. METHODS AND STUDY DESIGN: Healthy infants detected to have VDD (25OHD <25 nmol/L) in a population study were followed, and their demographics and clinical data were collected. RESULTS: One hundred and thirty-one subjects (boys = 66%) were included. Their first serum 25OHD was taken at a median age of 87.5 days. None were treated with high-dose vitamin D supplements, but some have been given vitamin D at 400 IU daily. They were assessed again at the median age of 252.5 days when 15 remained to have VDD and 26 were in the insufficient range (25 - 49.9nmol/L). All persistent VDD children were on exclusive breastfeeding. Exclusive breastfeeding and no vitamin D supplementation were significant risk factors for persistent vitamin D insufficiency (<50nmol/L). CONCLUSIONS: Persistent VDD is common among infants exclusively breastfeeding and those who did not receive vitamin D supplementation.

Rapid Spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Omicron Subvariant BA.2 in a Single-Source Community Outbreak.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant BA.2 sublineage has increased rapidly in Europe and Asia since January 2022. Here, we report the epidemiological and genomic analysis of a large single-source BA.2 outbreak in a housing estate. METHODS: We analyzed the epidemiological information on a community outbreak of BA.2 (STY outbreak). We performed whole viral genome sequencing using the Oxford Nanopore MinION device. We calculated the doubling time of the outbreak within a housing estate. RESULTS: The STY outbreak involved a total of 768 individuals as of 5 February 2022, including 432 residents, visitors, or staff (56.3%) from a single housing estate (KC Estate). The outbreak at the KC Estate had a short doubling time of 1.28 days (95% confidence interval: .560-1.935). The outbreak was promptly controlled with the lockdown of 3 buildings within the housing estate. Whole-genome sequencing was performed for 133 patients in the STY outbreak, including 106 residents of the KC Estate. All 133 sequences from the STY outbreak belonged to the BA.2 sublineage, and phylogenetic analysis showed that these sequences cluster together. All individuals in the STY cluster had the unique mutation C12525T. CONCLUSIONS: Our study highlights the exceptionally high transmissibility of the Omicron variant BA.2 sublineage in Hong Kong, where stringent measures are implemented as part of the elimination strategy. Continual genomic surveillance is crucial in monitoring the emergence of epidemiologically important Omicron sublineages.

Epidemiology of Acute Myocarditis/Pericarditis in Hong Kong Adolescents Following Comirnaty Vaccination.

BACKGROUND: Age-specific incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination in Asia is lacking. This study aimed to study the clinical characteristics and incidence of acute myocarditis/pericarditis among Hong Kong adolescents following Comirnaty vaccination. METHODS: This is a population cohort study in Hong Kong that monitored adverse events following immunization through a pharmacovigilance system for coronavirus disease 2019 (COVID-19) vaccines. All adolescents aged between 12 and 17 years following Comirnaty vaccination were monitored under the COVID-19 vaccine adverse event response and evaluation program. The clinical characteristics and overall incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination were analyzed. RESULTS: Between 14 June 2021 and 4 September 2021, 33 Chinese adolescents who developed acute myocarditis/pericarditis following Comirnaty vaccination were identified. In total, 29 (87.88%) were male and 4 (12.12%) were female, with a median age of 15.25 years. And 27 (81.82%) and 6 (18.18%) cases developed acute myocarditis/pericarditis after receiving the second and first dose, respectively. All cases are mild and required only conservative management. The overall incidence of acute myocarditis/pericarditis was 18.52 (95% confidence interval [CI], 11.67-29.01) per 100 000 persons vaccinated. The incidence after the first and second doses were 3.37 (95% CI, 1.12-9.51) and 21.22 (95% CI, 13.78-32.28 per 100 000 persons vaccinated, respectively. Among male adolescents, the incidence after the first and second doses were 5.57 (95% CI, 2.38-12.53) and 37.32 (95% CI, 26.98-51.25) per 100 000 persons vaccinated. CONCLUSIONS: There is a significant increase in the risk of acute myocarditis/pericarditis following Comirnaty vaccination among Chinese male adolescents, especially after the second dose.

Association of maternal levothyroxine use during pregnancy with offspring birth and neurodevelopmental outcomes: a population-based cohort study.

BACKGROUND: The influence of maternal levothyroxine treatment during pregnancy remains unclear. This study aimed to evaluate the associations of maternal levothyroxine treatment during pregnancy with the birth and neurodevelopmental outcomes in offspring. METHODS: This population-based cohort study was conducted among pregnant women using the Hong Kong Clinical Data Analysis and Reporting System. Mother-child pairs in Hong Kong from 2001 to 2015 were included and children were followed up till 2020. We defined the exposure group as mothers who were exposed to levothyroxine during pregnancy. Preterm birth and small for gestational age (SGA) were included as birth outcomes. Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) were included as neurodevelopmental outcomes. Odds ratios (OR) or hazard ratios (HRs) with a 95% confidence interval (CI) were evaluated to assess the association of gestational levothyroxine use with offspring birth and neurodevelopmental outcomes respectively, using propensity score fine-stratification weighting and a Cox proportional hazards regression model. RESULTS: Among 422,156 mother-child pairs, 2125 children were born from mothers exposed to levothyroxine during pregnancy. A significantly increased risk of preterm birth was observed in children with maternal levothyroxine exposure during pregnancy, when compared to mothers who had no history of thyroid-related diagnoses or prescriptions (weighted OR [wOR]: 1.22, 95% CI: 1.07, 1.39). Similarly, an increased risk of preterm birth was found among children of gestational levothyroxine users, when compared to children of mothers who had used levothyroxine before but stopped during pregnancy (wOR: 2.16, 95% CI: 1.09, 4.25). Sensitivity analysis, by excluding mothers exposed to psychotropic or antiepileptic medications before or during pregnancy, also indicated a similar increased risk of preterm birth regarding the gestational use of levothyroxine (wOR: 1.26, 95% CI: 1.10, 1.45). No significant association was observed for the risk of SGA, ADHD, and ASD. CONCLUSIONS: There is no evidence that gestational use of levothyroxine is associated with SGA, ADHD, or ASD in offspring. Gestational levothyroxine treatment is associated with a higher risk of preterm birth. Such risk might be confounded by the underlying maternal thyroid disease itself, however, we cannot completely exclude the possible effect of gestational L-T4 treatment on offspring preterm birth. Our findings provided support to the current guidelines on the cautious use of levothyroxine treatment during pregnancy.

Vitamin D and Ocular Diseases: A Systematic Review.

The contributory roles of vitamin D in ocular and visual health have long been discussed, with numerous studies pointing to the adverse effects of vitamin D deficiency. In this paper, we provide a systematic review of recent findings on the association between vitamin D and different ocular diseases, including myopia, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), dry eye syndrome (DES), thyroid eye disease (TED), uveitis, retinoblastoma (RB), cataract, and others, from epidemiological, clinical and basic studies, and briefly discuss vitamin D metabolism in the eye. We searched two research databases for articles examining the association between vitamin D deficiency and different ocular diseases. One hundred and sixty-two studies were found. There is evidence on the association between vitamin D and myopia, AMD, DR, and DES. Overall, 17 out of 27 studies reported an association between vitamin D and AMD, while 48 out of 54 studies reported that vitamin D was associated with DR, and 25 out of 27 studies reported an association between vitamin D and DES. However, the available evidence for the association with other ocular diseases, such as glaucoma, TED, and RB, remains limited.