Family context as a double-edged sword for psychological distress amid the COVID-19 pandemic with the mediating effect of individual fear and the moderating effect of household income.

Background: The COVID-19 pandemic drives psychological distress. Previous studies have mostly focused on individual determinants but overlooked family factors. The present study aimed to examine the associations of individual and family factors with psychological distress, and the mediating effect of individual fear and the moderating role of household income on the above associations. Methods: We conducted a population-based cross-sectional survey on Chinese adults in Hong Kong from February to March 2021 (N = 2,251) to measure the independent variables of anti-epidemic fatigue, anti-epidemic confidence, individual and family members' fear of COVID-19, and family well-being (range 0-10), and the dependent variable of psychological distress (through four-item Patient Health Questionnaire, range 0-4). Results: Hierarchical regression showed that anti-epidemic fatigue was positively (ß = 0.23, 95% CI [0.18, 0.28]) while anti-epidemic confidence was negatively (ß = -0.29, 95% CI [-0.36, -0.22]) associated with psychological distress. Family members' fear of COVID-19 was positively (ß = 0.11, 95% CI [0.05, 0.16]) while family well-being was negatively (ß = -0.57, 95% CI [-0.63, -0.51]) associated with psychological distress. Structural equation model showed that individual fear mediated the above associations except for family well-being. Multi-group analyses showed a non-significant direct effect of anti-epidemic confidence and a slightly stronger direct effect of family well-being on psychological distress among participants with lower incomes, compared to those with higher incomes. Conclusion: We have first reported the double-edged effect of family context on psychological distress, with the positive association between family members' fear of COVID-19 and psychological distress fully mediated by individual fear and the negative association between family well-being and psychological distress moderated by income level. Future studies are warranted to investigate how the contagion of fear develops in the family and how the inequality of family resources impacts family members' mental health amid the pandemic.

Development and evaluation of two brief digital health promotion game booths utilizing augmented reality and motion detection to promote well-being at a gerontechnology summit in Hong Kong.

Background: The acceleration of population aging calls for simple and effective interventions catered for older people. Gerontechnology, the combination of gerontology and technology, can promote quality of life in older adults. However, public health-related events incorporating information communication technology (ICT) for older people have seldom been evaluated. Objective: We reported the development and evaluation of two simple and brief digital health promotion games hosted at the annual Hong Kong Gerontech and Innovation Expo cum Summit (GIES) in 2018 and 2019 to promote well-being. Methods: Two game booths (Dinosaur Augmented Reality photo-taking in 2018, Sit-and-Stand fitness challenge in 2019) were designed by our interdisciplinary team. Four gaming technologies were employed: augmented reality, chroma key (green screen), motion detection and 3D modeling. Immediately after the game, we administered a brief questionnaire survey to assess participant satisfaction, happiness and perceived benefits, and collected qualitative data through observations and informal interviews. Results: Majority of 1,186 and 729 game booth participants in 2018 and 2019, respectively, were female (73.4% and 64.7%) and older adults (65.5 and 65.2%). Overall satisfaction toward the game booths was high (4.64 ± 0.60 and 4.54 ± 0.68 out of 5), with females and older adults reporting higher scores. Average personal and family happiness of participants in 2018 were 8.2 and 8.0 (out of 10). 90.3 and 18.4% of participants in 2019 chose one or more personal (e.g. enhance healthy living habits 62.4%, enhance personal happiness 61.6%) and family (e.g. enhance family happiness 15.6%, improve family relationships 10.8%) benefits of the game booth, respectively. Participants showed enthusiasm toward the technologies, and pride in their physical abilities in the fitness challenge. Conclusion: Our report on the development and evaluation of brief game interventions with ICT showed high satisfaction and immediate perceived benefits in community participants. Females and older adults reported higher satisfaction. Simple tools measuring happiness and perceived benefits showed positive results. Older adults were receptive and enthusiastic about the new technologies. Our findings can inform researchers and organizers of similar events. More research on simple and enjoyable ICT interventions is needed to attract older adults and promote their well-being. Trial registration: The research protocol was registered at the National Institutes of Health (Identifier number: NCT03960372) on May 23, 2019.

Worsening trends in self-rated health and correlates in Chinese adolescents in Hong Kong: a population-based panel study from 1999/2000 to 2014/15.

OBJECTIVES: To examine the 15-year secular trends of self-rated health (SRH) and correlates in Chinese adolescents in Hong Kong. DESIGN: A territory-wide population-based panel data study. SETTING: Anonymised records of the annual health examination from the Student Health Service, Department of Health in Hong Kong. PARTICIPANTS: 397 324 students in Secondary 2 (US grade 8), 335 902 in Secondary 4 and 113 892 in Secondary 6 during the academic year 1999/2000 and 2014/15. OUTCOME MEASURES: SRH and lifestyles were self-reported using standardised questionnaires. Sex-standardised and age-standardised prevalence of very poor/poor SRH and its secular annual changes across sex, grade, weight status, breakfast habits, and frequency/duration of aerobic exercises were examined. Their disparities over time were examined by interactions with the academic year in generalised estimating equations. RESULTS: The overall prevalence of very poor/poor SRH increased from 9.3% (95% CI: 8.9% to 9.7%) in 1999/2000 to 15.5% (15.1% to 15.8%) in 2014/15. Very poor/poor SRH was more prevalent in girls (adjusted OR: 1.02), in those having unemployed parents (1.29), being overweight (1.42) or obese (2.62), eating breakfast away from home (1.27) and skipping breakfast (1.49) or doing <1 time/week or ≤60 min/week aerobic exercises (1.78 and 1.88, respectively) than others. The corresponding disparities increased over time (ratios of OR: 1.006-1.042). CONCLUSIONS: Increasing prevalence of very poor/poor SRH from 1999/2000 to 2014/15 was found among Hong Kong Chinese adolescents, which was greater in girls, adolescents being overweight/obese and those having unemployed parents or unhealthy lifestyles. Strategies to reduce health inequality should consider multiple factors, especially modifiable factors including lifestyles.

Skipping Breakfast and Eating Breakfast Away From Home Were Prospectively Associated With Emotional and Behavioral Problems in 115,217 Chinese Adolescents.

BACKGROUND: Breakfast is deemed the most important meal of the day. We examined the prospective associations of breakfast habits with emotional/behavioral problems in adolescents and potential effect modification. METHODS: 115,217 Primary 6 students (United States Grade 6; mean age, 11.9; standard deviation [SD], 0.59 years) who attended the Student Health Service of Department of Health in Hong Kong in 2004/05, 2006/07, 2008/09 were followed till Secondary 6 (United States Grade 12). Emotional/behavioral problems were biennially examined using Youth Self-Report since Secondary 2 (United States Grade 8). Lifestyles were biennially examined using standardized questionnaires since Primary 6. Prospective associations of breakfast habit with emotional/behavioral problems and potential effect modification were examined using generalized estimating equations. RESULTS: Compared with eating breakfast at home, eating breakfast away from home was significantly associated with total emotional/behavioral problems and seven syndromes, including withdrawal, somatic complaints, anxiety/depression, thought problems, attention problems, delinquent behaviors, and aggressive behaviors (adjusted odds ratios [AORs] 1.22-2.04), while skipping breakfast showed stronger associations with the above problems and social problems (AORs 1.34-2.29). Stronger associations were observed in younger students for total and attention problems (P < 0.03) and in those with lower weight status for delinquent behaviors (P = 0.005). CONCLUSION: Eating breakfast away from home and especially skipping breakfast were prospectively associated with adolescent emotional/behavioral problems. The associations weakened with increasing age for total emotional/behavioral and attention problems, and weakened with higher weight status for delinquent behaviors, highlighting the vulnerability of younger and underweight children. If the associations are causal, increasing home breakfast may reduce adolescent emotional/behavioral problems and benefit psychosocial health.

Understanding longevity in Hong Kong: a comparative study with long-living, high-income countries.

BACKGROUND: Since 2013, Hong Kong has sustained the world's highest life expectancy at birth-a key indicator of population health. The reasons behind this achievement remain poorly understood but are of great relevance to both rapidly developing and high-income regions. Here, we aim to compare factors behind Hong Kong's survival advantage over long-living, high-income countries. METHODS: Life expectancy data from 1960-2020 were obtained for 18 high-income countries in the Organisation for Economic Co-operation and Development from the Human Mortality Database and for Hong Kong from Hong Kong's Census and Statistics Department. Causes of death data from 1950-2016 were obtained from WHO's Mortality Database. We used truncated cross-sectional average length of life (TCAL) to identify the contributions to survival differences based on 263 million deaths overall. As smoking is the leading cause of premature death, we also compared smoking-attributable mortality between Hong Kong and the high-income countries. FINDINGS: From 1979-2016, Hong Kong accumulated a substantial survival advantage over high-income countries, with a difference of 1·86 years (95% CI 1·83-1·89) for males and 2·50 years (2·47-2·53) for females. As mortality from infectious diseases declined, the main contributors to Hong Kong's survival advantage were lower mortality from cardiovascular diseases for both males (TCAL difference 1·22 years, 95% CI 1·21-1·23) and females (1·19 years, 1·18-1·21), cancer for females (0·47 years, 0·45-0·48), and transport accidents for males (0·27 years, 0·27-0·28). Among high-income populations, Hong Kong recorded the lowest cardiovascular mortality and one of the lowest cancer mortalities in women. These findings were underpinned by the lowest absolute smoking-attributable mortality in high-income regions (39·7 per 100 000 in 2016, 95% CI 34·4-45·0). Reduced smoking-attributable mortality contributed to 50·5% (0·94 years, 0·93-0·95) of Hong Kong's survival advantage over males in high-income countries and 34·8% (0·87 years, 0·87-0·88) of it in females. INTERPRETATION: Hong Kong's leading longevity is the result of fewer diseases of poverty while suppressing the diseases of affluence. A unique combination of economic prosperity and low levels of smoking with development contributed to this achievement. As such, it offers a framework that could be replicated through deliberate policies in developing and developed populations globally. FUNDING: Early Career Scheme (RGC ECS Grant #27602415), Research Grants Council, University Grants Committee of Hong Kong.

Use patterns of cigarettes and alternative tobacco products and socioeconomic correlates in Hong Kong secondary school students.

Smoking is a major cause of health inequities. However, sociodemographic differences in adolescent tobacco use are unclear. In a territory-wide school-based anonymous survey in 2018/19, we investigated tobacco use and sociodemographic correlates in 33,991 students (mean age 14.8 ± 1.9 years) in Hong Kong. Tobacco use prevalence and current-ever use ratios by sociodemographic factors were calculated. Generalised linear mixed models were used in association analyses. Current use was highest for cigarettes (3.2%), closely followed by alternative tobacco products (3.0%). Current-ever use ratios were highest for heated tobacco products (HTPs, 0.60), followed by nicotine e-cigarettes (0.52), waterpipe (0.51), and cigarettes (0.35). Use prevalence and current-ever use ratios of all products showed curvilinear relations with perceived family affluence (P values < 0.01), being highest in the richest families. Tobacco use was also associated with more senior grades, the lowest parental education, and boys, but current-ever use ratios of HTPs and waterpipe were higher in girls (P values < 0.05). The results suggested that adolescent ever users of nicotine-containing alternative tobacco products were more likely to keep using them than cigarettes, and the richest adolescents were at the highest risks of tobacco use. Diverse tobacco control measures are needed to improve health equity, especially on alternative tobacco products.

Digital inequalities in health information seeking behaviors and experiences in the age of web 2.0: A population-based study in Hong Kong.

BACKGROUND: Inequalities in health information seeking behaviors (HISBs) using mass media and internet websites (web 1.0) are well documented. Little is known about web 2.0 such as social networking sites (SNS) and instant messaging (IM) and experiences of HISBs. METHODS: We surveyed representative Hong Kong Chinese adults (N = 10143, 54.9% female; 72.3% aged 25-64 years) on frequency of HISBs using traditional sources, internet websites, SNS (e.g., Facebook, Twitter), and IM (e.g., WhatsApp, WeChat) and experiences measured using Information Seeking Experience Scale. Adjusted prevalence ratios (aPRs) for HISBs and experiences by sociodemographic and health-related characteristics were yielded using multivariable Poisson regression with robust variance estimators. aPRs for experiences by HISBs using internet websites, SNS, and IM adjusting for sociodemographic and health-related characteristics were also yielded. RESULTS: Being female, higher educational attainment, not smoking, and being physically active were associated with HISBs using any source (all P<0.05). Older age had decreased aPRs for HISBs using traditional sources (P for trend = 0.03), internet websites (P for trend<0.001), and SNS (P for trend<0.001) but not for IM (aged 45-64 years: aPR = 1.48, 95% CI 1.07, 2.03). Lower educational attainment and income were associated with negative experiences including feelings of effort and difficulties in understanding the information (all P for trend<0.05). Older age had increased aPRs for difficulties in understanding the information (P for trend = 0.003). Compared with internet websites, HISBs using IM was associated with feelings of frustration (aPR = 1.39, 95% CI 1.08, 1.79), difficulties in understanding the information (aPR = 1.36, 95% CI 1.12, 1.65), and quality concern (aPR = 1.20, 95% CI 1.08, 1.32). CONCLUSIONS: We identified correlates of web-based health information seeking and experiences in Hong Kong Chinese adults. Providing greater access to and improved information environment of web 2.0 to the target groups may help address digital inequalities.

Perceived Benefits and Harms of the COVID-19 Pandemic on Family Well-Being and Their Sociodemographic Disparities in Hong Kong: A Cross-Sectional Study.

We assessed the perceived benefits and harms of COVID-19 on family and their associations with sociodemographic factors in Chinese adults in Hong Kong. We conducted an online population-based survey and collected 4891 responses in 6 days. Prevalence estimates were weighted by sex, age, and education of the general population, and associations were analyzed using logistic regression. Our results showed both perceived benefits: 19.0% for family physical health, 7.2% family mental health, and 13.5% family relationships; and harms: 2.3% for family physical health, 37.9% family mental health, 18.6% family relationships, and 37.8% decreased family income. More female or older respondents reported perceived benefits but fewer of them reported perceived harms. More respondents with higher than lower socioeconomic scores (SES) reported perceived benefits on family physical and mental health and family relationships, but more respondents with lower than higher SES reported perceived harm on family income. As the pandemic continues with uncertainties, further studies on the dynamics of benefits and harms are needed. Urgent and additional assistance to underprivileged families and at-risk individuals are needed to reduce the inequities amidst the COVID-19 pandemic.

Heated tobacco products use in Chinese adults in Hong Kong: a population-based cross-sectional study.

INTRODUCTION: We investigated heated tobacco products (HTPs) use and associated factors in Chinese adults in Hong Kong where HTPs are not formally marketed yet, and cigarette smoking prevalence was the lowest in the developed world. METHODS: A population-based landline telephone survey in 2017 interviewed 5131 (45.2% male; 26.7% aged ≥60) adults to collect information on awareness, intention to use, ever use of HTPs, cigarette smoking status and sociodemographic characteristics. Descriptive statistics were weighted by the age, sex and smoking status of the Hong Kong adult population. Sociodemographics were mutually adjusted in logistic regression to yield adjusted ORs (AORs) for awareness of HTPs, controlling for smoking status. RESULTS: Overall, 11.3% (95% CI 10.0% to 12.7%) were aware of HTPs and 1.0 % (0.8%-1.2%) had ever used it. Awareness was associated with aged 40-49 years (AOR 1.37, 95% CI 1.01 to 1.87) or 30-39 years (2.03, 1.41-2.91) (vs ≥60 years), born in Hong Kong (1.37, 1.11-1.68) and higher monthly household income (p for trend 0.001). Ever HTP users had higher educational attainment and monthly household income, and more were aged 30-39 and economically active (all p<0.003). In never HTP users, intention to use HTPs (7.3%, 4.9%-10.8%) were more prevalent in respondents with similar characteristics (all p<0.008). More current (vs never) smokers were aware of HTPs, intent to use HTPs and had ever used HTPs (all p<0.001). CONCLUSION: Higher socioeconomic status was associated with HTP use and intention to use. Public health education on HTPs is needed especially for this high-risk group.

Effect of prepaid and promised financial incentive on follow-up survey response in cigarette smokers: a randomized controlled trial.

BACKGROUND: Monetary incentive is often used to increase response rate in smokers' survey, but such effect of prepaid and promised incentives in a follow-up survey is unknown. We compared the effect of different incentive schemes on the consent and retention rates in a follow-up survey of adult cigarette smokers. METHODS: This was a randomized controlled trial (RCT) in Hong Kong, China. Smokers who completed a non-incentivized baseline telephone smoking survey were invited to a 3-month follow-up, with randomization into (1) the control group (no incentive), (2) a promised HK$100 (US$12.8) incentive upon completion, (3) a promised HK$200 (US$25.6) incentive upon completion, or (4) a prepaid HK$100 incentive plus another promised HK$100 incentive ("mixed incentive"). Crude risk ratios from log-binomial regression models were used to assess if the 3 incentive schemes predicted higher rates of consent at baseline or retention at 3-month than no incentive. RESULTS: In total, 1246 smokers were enrolled. The overall consent and retention rates were 37.1 and 23.0%, respectively. Both rates generally increased with the incentive amount and offer of prepaid incentive. The mixed incentive scheme marginally increased the retention rate versus no incentive (26.8% vs 20.3%; risk ratio (RR) = 1.32; 95% CI: 1.00-1.76; P = 0.053), but not the consent rate (RR = 1.13; 95% CI: 0.93-1.38; P = 0.22). Among the consented participants, approximately 50% in the mixed incentive group received the mailed prepaid incentive, who achieved a higher retention rate than the group without incentives (82.8% vs 56.1%; RR = 1.48; 95% CI: 1.21-1.80; P < 0.01). CONCLUSION: The mixed incentive scheme combining the prepaid and promised incentive was effective to increase the follow-up retention rate by 48%. We recommend this mixed incentive scheme to increase the follow-up retention rate. More efficient methods of delivering the incentive are needed to maximize its effects. TRIAL REGISTRATION: U.S. Clinical Trials registry (clinicaltrials.gov, retrospectively registered, reference number: NCT03297866 ).

Increasing socioeconomic disparities in sedentary behaviors in Chinese children.

BACKGROUND: Sedentary behaviors are prevalent in Chinese children, however, the studies on their trends and socioeconomic disparities are scarce. We examined the time trends of daily television (TV) viewing and video game playing and the associated socioeconomic factors in Chinese children in Hong Kong, the most developed and westernized city in China. METHODS: In a panel data study involving 538,300 primary four and 510,294 primary six students from 1999/2000 to 2008/09, data on socioeconomic status, sedentary behaviors (TV viewing and video game playing) and other lifestyle habits were collected using a self-administered questionnaire. Trends in sedentary behaviors over time were assessed. Their socioeconomic disparities were examined by interactions in generalized estimating equations with the adjustment for weight status and extracurricular physical activities. RESULTS: The age and sex-standardized prevalence of ≥2 h daily TV viewing decreased from 51.4% (95% confidence interval [CI] 51.1-51.8%) in 1999/2000 to 43.8% (95% CI 43.4-44.2%) in 2008/09 (P for trend < 0.001), whereas that of ≥1 h daily video game playing increased from 8.2% (95% CI 7.9-8.4%) to 22.4% (95% CI 22.0-22.7%). Both sedentary behaviors were more prevalent in boys than girls, but the disparities decreased over time (Ratio of odds ratio [ROR] = 0.996 and 0.924 for TV viewing and video game playing, respectively). In contrast, both sedentary behaviors were increasingly more prevalent in children whose parents had lower education levels or non-managerial/professional occupations (ROR 1.006-1.082). CONCLUSIONS: Children in lower socioeconomic families in Hong Kong were increasingly at risk of having sedentary behaviors over years and thus deserve more attention. Effective strategies targeting children and/or their parents of lower socioeconomic status are needed to reduce sedentary behaviors.

Favourable Perceptions of Electronic Cigarettes Relative to Cigarettes and the Associations with Susceptibility to Electronic Cigarette Use in Hong Kong Chinese Adolescents.

We investigated favourable perceptions of electronic cigarettes (ECs) relative to cigarettes and their associations with EC use susceptibility in adolescents. Hong Kong Chinese Secondary 1-6 (U.S. grade 7-12) students (n = 40,202) were surveyed in 2014/2015 on EC use, cigarette smoking, favourable perceptions of ECs relative to cigarettes, EC use susceptibility, family smoking, and socio-demographic characteristics. Cox regression yielded adjusted prevalence ratios (APRs) of EC use susceptibility in never users, excluding those unaware of ECs. In all students, 8.9% were ever EC users, 47.2% reported favourable perceptions of ECs relative to cigarettes, such as less likely to cause accidents (25.2%) and less harmful to users (24.5%), and 28.9% did not know ECs. Among never EC users who were aware of ECs (n = 24,663), EC use susceptibility was associated with each of the favourable perceptions, especially greater attractiveness (APR 2.84, 95% CI 2.53-3.19), and better parental (2.75, 2.41-3.15) and school acceptability (2.56, 2.15-3.05). An increased number of favourable perceptions of ECs relative to cigarettes was associated more strongly with the susceptibility (p for trend < 0.001). Our findings inform strategies to reduce unwarranted favourable perceptions and prevent adolescent EC use.

Living with Smoker(s) and Smoking Cessation in Chinese Adult Smokers: Cross-Sectional and Prospective Evidence from Hong Kong Population Health Survey.

Background: Results on the environmental influence on unassisted quitting are scarce. We investigated the associations of living with smoker(s) with quitting in Chinese adult smokers. Methods: We examined both cross-sectional and prospective data in the Hong Kong Population Health Survey recruited participants in 2003/04, and followed up to 2006. Unconditional logistic regression yielded adjusted odds ratios (AORs) of (i) planning to quit, (ii) ex-smoking (cross-sectional), and quitting (prospective) for living with smoker(s). 1679 ever smokers aged 18+ years at baseline, and 323 of them who were successfully followed-up were included in the cross-sectional, and prospective analysis. Results: At baseline, living with smoker(s) was significantly associated with lower odds of planning to quit in current smokers (AOR 0.41, 95% CI 0.25-0.68), and lower odds of ex-smoking (AOR 0.45, 95% CI 0.34-0.58), particularly if the smoker(s) smoked inside home (AOR 0.35, 95% CI 0.26-0.47). Prospectively, living with smoker(s) non-significantly predicted lower odds of new quitting (AOR 0.48, 95% CI 0.13-1.78). Conclusions: Our study has provided the first evidence in a Chinese general population that living with smoker(s) is an important barrier against smoking cessation. To boost quit rate in nonusers of smoking cessation services, smoking at home should be banned, especially for populations living in crowed urban environments that are typical of economically developed cities in China.

Associations of unhappiness with sociodemographic factors and unhealthy behaviours in Chinese adolescents.

Background: Evidence on the effects of lack of physical exercise, alcohol drinking and smoking on happiness is limited and inconsistent. We examined the associations of unhappiness with sociodemographic factors and these unhealthy behaviours in Chinese adolescents. In a school-based survey in 2012-13 in Hong Kong, 45 857 secondary school students (mean age 14.8 years, 54.0% boys) reported their happiness level (not happy at all/not very happy/happy/very happy), frequency of physical exercise, alcohol drinking status, smoking status and sociodemographic factors. A main and a sensitivity analysis examined the associations of unhappiness with the study factors, treating unhappiness as a binary (combining 'not happy at all' and 'not very happy') and a four-level ordered variable, respectively. The main and the sensitivity analysis both showed that unhappiness was associated with older age, very poor families, non-intact families, more co-residing smokers, lack of physical exercise and alcohol drinking; current smokers were unhappier than never and ex-smokers; unhappiness also increased significantly with the number of unhealthy behaviours ( P for trend < 0.001). In Chinese adolescents, unhappiness levels were higher in those who had a very poor family, a non-intact family and more co-residing smokers, and in those who were physically inactive, drank alcohol and smoked.

Waterpipe smoking among secondary school students in Hong Kong.

OBJECTIVES: To examine the prevalence of waterpipe smoking and its associated factors among adolescents in Hong Kong. METHODS: We analyzed data of the School-based Survey on Smoking among Students 2012/2013 from a representative sample of 45,857 secondary school students in Hong Kong (mean age 14.8, SD 1.9). We conducted Chi-square tests and t test to compare current (past 30 days) waterpipe users and nonusers by sociodemographic variables and other covariates. Univariate and multivariable logistic regression models were used to examine the factors associated with current waterpipe smoking. RESULTS: Overall, 1.2 % of students reported current waterpipe smoking, of whom 43 % reported concurrent use of cigarettes. Waterpipe was the most popular alternative tobacco product (non-cigarette) used by students. Current waterpipe smoking was associated with older age, male sex, higher self-perceived family financial status, poor knowledge about the harm of cigarette smoking, positive attitudes toward smoking, current cigarette smoking, other tobacco use, and alcohol consumption. CONCLUSIONS: Waterpipe smoking was the most popular alternative tobacco product among Hong Kong adolescents. Despite the low prevalence, it should be routinely monitored. Education programs and cessation interventions need to address waterpipe smoking in addition to cigarette smoking.

Sociodemographic risk factors of alcohol drinking in Hong Kong adolescents.

BACKGROUND: Adolescent drinking in Western countries has been associated with older age and high socioeconomic status, but the association with family structure was inconsistent. METHODS: In a 2012-2013 school-based survey in Hong Kong, 23,096 students (mean age 14.7 years, SD 1.8 years) completed an anonymous questionnaire. Current drinking was defined as any drinking and binge drinking as consuming at least 5 drinks on one occasion, both in the past 30 days. Multilevel logistic regression was used to examine the association of sociodemographic characteristics with current drinking, binge drinking and type of alcohol consumed. RESULTS: Current drinking was associated with age (≥ 15 vs ≤ 14 years) (adjusted OR 1.87, 95% CI 1.74 to 2.02), higher perceived family affluence versus low affluence (1.11, 1.02 to 1.21 for medium affluence; 1.55, 1.38 to 1.75 for high affluence), private housing versus public housing (1.11, 1.01 to 1.21) and non-intact family versus intact family (1.31, 1.19 to 1.45 for separated/divorced parents; 1.40, 1.21 to 1.62 for one or both deceased parents). Similar risk factors were observed for binge drinking. Girls were more likely to drink fruit wine (1.48, 1.36 to 1.62), while they were less likely to drink beer (0.85, 0.79 to 0.92) and spirits (0.69, 0.54 to 0.87). Students who reported high family affluence were more likely to drink wine (1.91, 1.59 to 2.30) and spirits (2.23, 1.54 to 3.24). CONCLUSIONS: Generally, adolescents who were older and had higher socioeconomic status were more likely to drink. High family affluence was associated with wine and spirits drinking. Beer and spirits were preferred more by boys, and fruit wine by girls. These results indicated high-risk groups for adolescent alcohol interventions.

Electronic cigarette use and its association with smoking in Hong Kong Chinese adolescents.

BACKGROUND: Electronic cigarettes (e-cigarettes) are increasingly used in adolescents with unknown impacts on conventional cigarette smoking. We examined the associations of e-cigarette use with smoking intention, nicotine addiction and smoking cessation in Chinese adolescents. METHODS: A total of 45,128 students (age 14.6 ± 1.9; boys 51.4%) from 75 randomly selected schools in Hong Kong reported e-cigarette use (in the past 30 days), conventional cigarette use and socio-demographic characteristics in an anonymous questionnaire survey. Adjusted odds ratios (AORs) of intention to smoke, morning smoking urge, intention to quit and quit attempts; and beta-coefficient (ß) of cigarette consumption per day were calculated in relation to e-cigarette use. RESULTS: E-cigarette use was associated with intention to smoke with an AOR (95% CI) of 1.74 (1.30-2.31) in all students, 2.18 (1.12-4.23) in never and 2.79 (2.05-3.79) in ever smokers (non-significant interaction by smoking status). The associations were also significant in experimental and former smokers but not in current smokers. In current smokers, e-cigarette use was significantly associated with heavier smoking (ß 2.54, 95% CI 1.28-3.81) and morning smoking urge (AOR 2.54, 95% CI 1.50-3.11), and non-significantly associated with lower quit intention (0.76, 0.52-1.09) and attempts (0.80, 0.56-1.23). CONCLUSIONS: E-cigarette use was associated with smoking intention in never, experimental and former smokers in Hong Kong Chinese adolescents. In current smokers, e-cigarette use was associated with nicotine addiction but not quit intention and attempts. Prospective studies with detailed measurements on e-cigarette use are warranted for further studies.

Assessment of weight-related factors of adolescents by private practitioners.

BACKGROUND: Few studies have examined how common physicians assess various weight-related variables and patient characteristics that predict such assessments based on adolescents' reports. We aimed to examine how common adolescents received weight-related physical measurements and lifestyle enquiries (dietary habits and physical activity) from private practitioners and to identify factors associated with these assessments. METHODS: In the Hong Kong Student Obesity Surveillance (HKSOS) project, 33692 students (44.9% boys; mean age 14.8, SD 1.9 years, age range 11-18) from 42 randomly selected schools completed an anonymous questionnaire. The students were asked "In the past 12 months, has any private practitioners (or their nurses) measured or asked about these items?" Response options included height, weight, waist circumference (WC), blood pressure (BP), BMI, diet, and physical activity. Weight status was based on self-reported weight and height. Logistic regression was used to identify student characteristics associated with each assessment. Analyses were conducted using STATA 10.0. RESULTS: Among 13283 students who had doctor consultations in the past 12 months, 37.9% received physical measurements or lifestyle enquiries, with weight (20.8%), height (16.8%) and blood pressure (11.5%) being the most common, followed by diet (8.1%), BMI (6.3%), WC and physical activity (both 4.6%). In general, adolescents who were female, older, underweight or overweight/obese, had parents with higher education level, and had actively asked private practitioners for advice about weight were more likely to receive assessments of weight-related factors. CONCLUSIONS: Weight-related factors in adolescents were infrequently assessed by private practitioners in Hong Kong. Generally, unhealthy weight, higher parental education and advice-seeking by adolescents predicted these assessments.

Secondhand smoke exposure and health services use among adolescent current smokers.

BACKGROUND: To investigate the associations of secondhand smoke (SHS) exposure with medical consultation and hospitalisation among adolescents in Hong Kong. METHODS: A total of 35827 secondary 1 (US grade 7) to secondary 5 students from 85 randomly selected schools completed an anonymous questionnaire on smoking, SHS at home, SHS outside home, medical consultation in the past 14 days, hospitalisation in the past 12 months, and socio-demographic characteristics. Current smoking was defined as any smoking in the past 30 days. SHS exposure was classified as none (reference), 1-4 and 5-7 days/week. Logistic regression yielded adjusted odds ratios (AORs) for medical consultation and hospitalisation in relation to SHS exposure at home and outside home in current smokers. Analyses were also done among never-smokers for comparison. RESULTS: Among all students, 15.9% had medical consultation and 5.2% had been hospitalised. Any SHS exposure at home was associated with AORs (95% CI) for medical consultation and hospitalisation of 1.69 (1.14-2.51) and 2.85 (1.47-5.52) in current smokers, and 1.03 (0.91-1.15) and 1.25 (1.02-1.54) in never-smokers, respectively, (P<0.01 for interaction between smoking status and SHS exposure at home). SHS exposure outside home was generally not associated with medical consultation and hospitalisation in smokers and never-smokers. CONCLUSIONS: SHS exposure at home was associated with health services use among adolescent current smokers. Adolescent smokers should be aware of the harm of SHS in addition to that from their own smoking. The evidence helps health care professionals to advise adolescent smokers to avoid SHS exposure and stop smoking.

Sleep and academic performance in Hong Kong adolescents.

BACKGROUND: Sleep problems may have different influences on students' academic performance. We investigated the prevalence of sleep patterns, naps, and sleep disorders, and their associations with academic performance in Hong Kong adolescents. METHODS: In 2007-2008, 22,678 students aged 12-18 (41.6% boys) completed a questionnaire on sociodemographic characteristics, sleep patterns and problems, and lifestyle factors including exercise, smoking, alcohol drinking, and academic performance. RESULTS: The prevalence of having >8 hours of sleep was higher on holiday nights (86.4%) than on school-day nights (27.4%). Sleeping after midnight was more common before holidays (49.3%) than before school days (19.9%). Symptoms of insomnia and obstructive sleep apnea (OSA) were reported by 21.5% and 34.4% of students. Having >2 hours of weekend sleep delay was associated with poor academic performance with an odds ratio (OR) (95% confidence interval) of 1.46 (1.29-1.65). However, having 1-2 hours and >2 hours of weekend wake-up delay were both associated with less likelihood of poor academic performance with ORs of 0.64 (0.56-0.73) and 0.69 (0.59-0.80). Other factors associated with poor academic performance included >2 hours of sleep debt, OR of 1.17 (1.03-1.33); having any insomnia symptoms in the past 30 days, OR of 1.27 (1.17-1.37); and having any OSA symptoms at least weekly, OR of 1.23 (1.14-1.32). Napping in the past 5 school days was only marginally associated with poor school performance with an OR of 1.08 (1.00-1.16). CONCLUSION: Poorer academic performance was associated with sleep debt, and symptoms of insomnia and OSA. Sleep compensation but not naps may be a protective factor of poor academic performance.