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.

Patient enablement and health-related quality of life for patients with chronic back and knee pain: a cross-sectional study in primary care.

BACKGROUND: Chronic back and knee pain impairs health- related quality of life (HRQoL) and patient enablement can improve HRQoL. AIM: To determine whether enablement was a moderator of the effect of chronic back and knee pain on HRQoL. DESIGN AND SETTING: A cross-sectional study of Chinese patients with chronic back and knee problems in public primary care clinics in Hong Kong. METHOD: Each participant completed the Chinese Patient Enablement Instrument-2 (PEI-2), the Chinese Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Pain Rating Scale (PRS). Multivariable regression examined the effects of PRS score and PEI-2 score on WOMAC total score. A moderation regression model and simple slope analysis were used to evaluate whether the interaction between enablement (PEI-2) and pain (PRS) had a significant effect on HRQoL (WOMAC). RESULTS: Valid patient-reported outcome data from 1306 participants were analysed. PRS score was associated with WOMAC total score (ß = 0.326, P<0.001), whereas PEI-2 score was associated inversely with WOMAC total score (ß = -0.260, P<0.001) and PRS score. The effect of the interaction between PRS and PEI-2 (PRS × PEI-2) scores on WOMAC total score was significant (ß = -0.191, P<0.001) suggesting PEI-2 was a moderator. Simple slope analyses showed that the relationship between PRS and WOMAC was stronger for participants with a low level of PEI-2 (gradient 3.056) than for those with a high level of PEI-2 (gradient 1.746). CONCLUSION: Patient enablement moderated the impact of pain on HRQoL. A higher level of enablement can lessen impairment in HRQoL associated with chronic back and knee pain.

Comparing self-reported reactogenicity between adolescents and adults following the use of BNT162b2 (Pfizer-BioNTech) messenger RNA COVID-19 vaccine: a prospective cohort study.

OBJECTIVES: Although clinical data have shown that the BNT162b2 vaccine, which is widely used in many countries, is safe and effective as a protection against the SARS-CoV-2 infection, extant research in adverse reactions using real-world data of various sociodemographic characteristics is scant. METHODS: We conducted a prospective cohort study to compare age differences in self-reported reactogenicity of BNT162b2 in Hong Kong. A total of 1,516 participants were intensively followed up for two weeks following both doses of BNT162b2 vaccination, during which their basic demographic, health conditions, and medication information were collected. RESULTS: Results from the generalized mixed model showed that compared with adults aged 18 to 59 years, older adults aged 60 years or above had a lower risk of adverse reactions and adolescents aged 12 to 17 years had a moderately higher risk. CONCLUSIONS: Results of this study should be informative to parents considering BNT162b2 vaccination for their children in that moderately increased reactogenicity compared with adults is anticipated.

Does obesity persist from childhood to adolescence? A 4-year prospective cohort study of chinese students in Hong Kong.

BACKGROUND: Little is known about the progression of obesity from childhood to adolescence. This study aimed to longitudinally examine the obesity status in a cohort of children across their childhood and adolescence, and to identify the factors associated with persistent obesity. METHODS: The study used data from School Physical Fitness Award Scheme (SPFAS), a population-based programme in Hong Kong primary and secondary schools. Students were included if they participated in the SPFAS in both 2014 (Primary 1 and 2) and 2018 (Primary 5 and 6). Their anthropometric and physical fitness parameters were analyzed. RESULTS: A total of 18,863 students were included. The baseline prevalence of obesity was 5.7 %. After 4 years, the prevalence increased to 6.7 %. Among those with obesity at baseline, 35.3 % remained obese after 4 years. The addition of baseline physical fitness level did not improve the prediction for persistent obesity. CONCLUSIONS: One-third of obese students in junior primary school remained to be obese into adolescence. Their baseline physical fitness level did not improve the predictive value for future obesity. Further studies should investigate the prognostic factors that may influence the natural course of childhood obesity.

Development and pilot evaluation of a mobile app on parent-child exercises to improve physical activity and psychosocial outcomes of Hong Kong Chinese children.

BACKGROUND: Parent-child exercises involve children and parents to do workout together and have positive effects on physical and mental health. We developed a mobile app on parent-child exercises called Family Move, which combines coaching videos with game features such as points and level system to enhance the health and wellbeing of both children and parents through parent-child exercises. This pilot pre-post study investigated whether the Family Move app-based intervention had a positive effect on children's health-related quality of life (HRQOL), psychosocial wellbeing, and physical activity (PA) level. METHODS: We recruited 67 parent-child pairs. During the 8-week intervention, these pairs were invited to perform parent-child exercises using the Family Move app. Points were automatically added to the user account after viewing a coaching video. In-game ranking was available to enhance user engagement. Parent proxy-report questionnaires on children's HRQOL, psychosocial wellbeing, and PA were administered at baseline and 1- and 6-month follow-up. Paired samples t-tests were conducted to evaluate post-intervention changes in child outcomes (HRQOL, psychosocial wellbeing, and PA). Multiple linear regressions were used to examine these changes as a function of in-game ranking. RESULTS: 52 (78%) viewed at least one coaching video in the Family Move app. Children's PA level significantly increased at 1-month (d = 0.32, p = 0.030) and 6-month (d = 0.30, p = 0.042) follow-up, whereas their psychosocial problems declined at 6-month follow-up (d = 0.35, p = 0.005). Higher in-game ranking was significantly associated with fewer psychosocial problems at 1-month follow-up (ß = - 0.15, p = 0.030). CONCLUSIONS: Our findings suggest that the Family Move app could be a possible intervention to increase children's PA level and psychosocial wellbeing through parent-child exercise. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT03279354 , registered September 11, 2017 (Prospectively registered).

Effect of Pokémon Go on Self-Harm Using Population-Based Interrupted Time-Series Analysis: Quasi-Experimental Study.

BACKGROUND: Pokémon Go is a very popular location-based augmented reality game with widespread influences over the world. An emerging body of research demonstrates that playing Pokémon Go can lead to improvements in physical activity and psychosocial well-being; however, whether Pokémon Go reduces self-harm incidence at the population-level is still questionable. OBJECTIVE: This study aimed to quantify how the launch of Pokémon Go in Hong Kong affected the incidence of self-harm using a quasi-experimental design. METHODS: An interrupted time-series design with Poisson segmented regression adjusted for time and seasonality trends was used on data from 2012 to 2018 to detect any changes in the number of accident and emergency attendances due to self-harm, after Pokémon Go was launched. The findings were validated using a baseline control period and using other intentional injuries and minor noninjuries as control outcomes. We also assessed intervention effects by age group. RESULTS: From January 1, 2012 to July 31, 2018, there were 13,463 accident and emergency attendances due to self-harm in Hong Kong. During the period after launching Pokémon Go, self-harm attendances dropped by 34% (adjusted incidence rate ratio: 0.66, 95% CI 0.61-0.73). When analyzed by age group, a reduction in self-harm incidence was only apparent in adults (18 to 24 years of age: adjusted incidence rate ratio: 0.78, P=.02; 25 to 39 years of age: adjusted incidence rate ratio: 0.75, P<.001; 40 years of age and older: adjusted incidence rate ratio: 0.57, P<.001). CONCLUSIONS: Self-harm incidence in the population, particularly in adults, showed a significant decline in the period after Pokémon Go was launched. Augmented reality games such as Pokémon Go show great promise as a tool to enhance psychosocial well-being and improve mental health.

Linking Healthcare and Social Service Databases to Study the Epidemiology of Child Maltreatment and Associated Health Problems: Hong Kong's Experience.

OBJECTIVE: To examine the incidence and trend of child maltreatment and its associated health problems in Hong Kong by linking healthcare and social service databases. STUDY DESIGN: Data on 4816 children under the age of 18 years registered with the Child Protection Registry and matching health records in public hospitals in Hong Kong from 2003 to 2010 were extracted. Associations were examined between different types of child maltreatment and child's medical diagnosis according to the International Statistical Classification of Diseases and Related Health Problems, 10th Revision codes including suicidal attempt (X60-X84), nonchild maltreatment related injuries (S00-S99; T00-T98, excluding T74 and T76 that are maltreatment related injuries), mental health problems (F00-F99), and congenital malformations/chromosomal abnormalities (Q00-Q99). RESULTS: Significant rising trends were found for child physical abuse, neglect, and sexual abuse during the period from 2003 to 2010. Psychological abuse remained stable. Risk of suicide attempt was higher among children suffering from sexual abuse, psychological abuse, and children experiencing multiple abuses; mental health diagnoses were more common in victims of psychological and multiple abuses. Congenital malformations and chromosomal abnormalities were more commonly found among neglected children. CONCLUSIONS: In contrast to the decreasing trend observed in the West during the study period, there has been an escalating trend in child maltreatment in Hong Kong and child maltreatment is strongly associated with major health problems. This is one of the first studies to demonstrate the power of linking healthcare and social service databases, which allows for both a better understanding of the impact of child maltreatment and as a guide future policy and service planning.

A prospective cohort study to investigate parental stress and child health in low-income Chinese families: protocol paper.

INTRODUCTION: Chronic stress has adverse effects on health. Adults and children from low-income families are subject to multiple sources of stress. Existing literature about economic hardship mostly focuses on either adults or children but not both. Moreover, there is limited knowledge on the relationship between parental generalised stress and child health problems. This study aims to explore the bidirectional relationship between parental stress and child health in Chinese low-income families and to identify other modifiable factors influencing this relationship. METHODS AND ANALYSIS: This prospective cohort study will sample 254 low-income parent-child pairs and follow them up for 24 months with assessments at three time points (baseline, 12 and 24 months) on parental stress, health-related quality of life (HRQOL) and child health and behaviour using both subjective measures and objective physiological parameters. This study will collect data using standardised measures on HRQOL and behaviours of children as well as on HRQOL, mental health and stress levels of parents along with physiological tests of allostatic load and telomere length. The mediating or moderating effect of family harmony, parenting style and neighbourhood conditions will also be assessed. Data will be analysed using latent growth modelling and cross-lagged path analysis modelling to examine the bidirectional effect of parental stress and child health over time. Mediation and moderation analysis will also be conducted to examine the mechanism by which the variables relate. ETHICS AND DISSEMINATION: This study was approved by the institutional review board of the University of Hong Kong-the Hospital Authority Hong Kong West Cluster, reference no: UW 16-415. The study findings will be disseminated through peer-reviewed publications and international conferences. TRIAL REGISTRATION NUMBER: NCT03185273; Pre-results.

Maternal mental quality of life mediates the associations between intimate partner abuse against mothers and their children's behaviours and quality of life in low-income Chinese families.

PURPOSE: To explore the association between maternal intimate partner abuse (IPA) and their children's health-related quality of life (HRQOL) and behavioural problem, and to establish a mediation model and investigate the mediating role of mothers' HRQOL on this association. METHODS: A cross-sectional study was conducted on 197 mothers of 227 children (112 boys and 115 girls) from low-income Chinese families. The mothers were asked to complete the 5-item abuse assessment screen questionnaire for the presence of IPA, the Chinese (Hong Kong) version of 12-item Short-Form Health Survey (SF-12) for their HRQOL and a structured socio-demographics questionnaire. One of the parents completed the Child Health Questionnaire-Parent Form-50 (CHQ-PF50) and the strengths and difficulties questionnaire (SDQ) to report on their children's HRQOL and behavioural problems, respectively. The mediating effect of the maternal HRQOL on the relationship between maternal IPA status and their children's behavioural problems and HRQOL was tested using Baron and Kenney's multistage regression approach and bootstrapping method. RESULTS: Thirty-five of the 197 mothers reported IPA (17.8%). Children whose mothers had experienced IPA had lower scores in the CHQ-PF50 mental health, parental impact-emotional, family activities and family cohesion subscales, and the psychosocial summary score compared to children of mothers who reported no IPA; they also had more emotional, conduct and hyperactivity/inattention problems and higher total difficulties scores measured by the SDQ. Maternal mental HRQOL was a mediator on the relationship between maternal IPA status and their children's behavioural problems and psychosocial HRQOL. CONCLUSION: IPA experienced by mothers had significant negative impacts on their children's HRQOL and behaviours, which was mediated by maternal mental HRQOL.