Association between tobacco industry denormalisation beliefs and support for tobacco endgame policies: a population-based study in Hong Kong.

OBJECTIVES: To examine the associations between tobacco industry denormalisation (TID) beliefs and support for tobacco endgame policies. METHODS: A total of 2810 randomly selected adult respondents of population-based tobacco policy-related surveys (2018-2019) were included. TID beliefs (agree vs disagree/unsure) were measured by seven items: tobacco manufacturers ignore health, induce addiction, hide harm, spread false information, lure smoking, interfere with tobacco control policies and should be responsible for health problems. Score of each item was summed up and dichotomised (median=5, >5 strong beliefs; ≤5 weak beliefs). Support for tobacco endgame policies on total bans of tobacco sales (yes/no) and use (yes/no) was reported. Associations between TID beliefs and tobacco endgame policies support across various smoking status were analysed, adjusting for sociodemographics. RESULTS: Fewer smokers (23.3%) had strong beliefs of TID than ex-smokers (48.4%) and never smokers (48.5%) (p<0.001). Support for total bans on tobacco sales (74.6%) and use (76.9%) was lower in smokers (33.3% and 35.3%) than ex-smokers (74.3% and 77.9%) and never smokers (76.0% and 78.3%) (all p values<0.001). An increase in the number of TID beliefs supported was positively associated with support for a total ban on sales (adjusted risk ratio 1.06, 95% CI 1.05 to 1.08, p<0.001) and use (1.06, 95% CI 1.05 to 1.07, p<0.001). The corresponding associations were stronger in smokers than non-smokers (sales: 1.87 vs 1.25, p value for interaction=0.03; use: 1.78 vs 1.21, p value for interaction=0.03). CONCLUSION: Stronger TID belief was associated with greater support for total bans on tobacco sales and use. TID intervention may increase support for tobacco endgame, especially in current smokers.

Corrigendum: Risk perceptions and changes in tobacco use in relation to Coronavirus Disease 2019 pandemic: A qualitative study on adolescent tobacco users in Hong Kong.

[This corrects the article DOI: 10.18332/tid/167479.].

Risk perceptions and changes in tobacco use in relation to Coronavirus Disease 2019 pandemic: A qualitative study on adolescent tobacco users in Hong Kong.

INTRODUCTION: Tobacco use is associated with an increased risk of Coronavirus Disease 2019 (COVID-19) infection, severe COVID-19 outcomes requiring intensive care, and mortality. We investigated the perceived risk of and changes in cigarette, e-cigarette (EC) and heated tobacco product (HTP) use in relation to COVID-19 in Hong Kong adolescent tobacco users. METHODS: We conducted semi-structured telephone interviews from January to April 2021 and in February 2022 on 40 adolescents (65% boys, Secondary school grades 2-6) who participated in our previous smoking surveys and were using cigarettes, ECs or HTPs before the first wave of the COVID-19 pandemic in January 2020. RESULTS: Adolescents generally perceived higher risks of contracting and having more severe COVID-19 from using cigarettes than ECs/HTPs, but they had limited knowledge of COVID-19 risks from EC/HTP use, particularly. Both increased and reduced consumption were found in tobacco, with EC use being the less affected product. Changes also included switching to ECs for convenience and lower cost and shifting from smoking cigarettes outside to mainly at home or in hidden areas. COVID-related policies, fear of infection, non-COVID-related health concerns, less social opportunities and pocket money, and limited access to tobacco products were barriers to tobacco use. In contrast, greater freedom at home versus school and negative emotions due to social distancing were facilitators. Family/peer influence had mixed impacts. CONCLUSIONS: Adolescent tobacco users perceived lower COVID risks associated with HTPs and ECs than cigarettes, and various changes in tobacco use were found amid the pandemic in Hong Kong. COVID-19 and related social changes may both facilitate or deter adolescent tobacco use.

Impact of mandatory masking amid the COVID-19 pandemic on outdoor smoking: an interrupted time-series analysis of a 33-month unobtrusive observational study.

Background: Mask-wearing in outdoor public places in Hong Kong was mandated on 29 July 2020, amid the COVID-19 pandemic. We aimed to evaluate the impact of mandatory masking with no exemption for smoking on outdoor smoking. Methods: We conducted 253 unobtrusive observations at 10 outdoor smoking hotspots in 33 months from July 2019 to March 2022 and counted smokers and non-smoking pedestrians in fixed boundaries. We conducted interrupted time-series analyses on the monthly mean volume of smokers (persons per hour) using generalized linear models. The independent variables were as follows: time since the first observation, implementation of the mask regulation, time since the regulation, seasonality, and waves 1-5 outbreaks. We checked the robustness of the association using the daily mean volume of smokers as the dependent variable. Two sensitivity analyses were conducted to include the hotspot location or the number of all pedestrians as an offset. Results: Monthly outdoor smoking decreased immediately after the regulation (incidence rate ratio [IRR]: 0.505, 95% confidence interval [CI]: 0.374 to 0.680, P < 0.001). Daily smoking analysis and the two sensitivity analyses supported the results. However, monthly outdoor smoking increased by 11% since the regulation (IRR: 1.110, 95% CI: 1.074 to 1.147, P < 0.001). An exception was observed at the most severe wave 5 outbreak when monthly outdoor smoking decreased (IRR: 0.415, 95% CI: 0.327 to 0.525, P < 0.001). Conclusion: Outdoor smoking fell immediately after mandatory masking, rebounded to pre-pandemic levels, and decreased again at the most severe wave 5.

Cognitive Activities, Lifestyle Factors, and Risk of Cognitive Impairment, with an Analysis of the Apolipoprotein Epsilon 4 Genotype.

INTRODUCTION: Cognitive stimulating activities and a healthy lifestyle are associated with less cognitive impairment. However, whether the association is varied by Apolipoprotein epsilon 4 (APOE ε4) allele carrier status remains inconclusive. We aimed to investigate whether the association of cognitively stimulating activities and a healthy lifestyle with the risk of cognitive impairment varied by APOE ε4 allele carrier status. METHODS: A case-control study was conducted for adults aged 60 years and above. Six province administrative units (Beijing, Shanghai, Hubei, Sichuan, Guangxi, and Yunnan) were included using stratified multistage cluster sampling. A total of 1,300 individuals were identified with cognitive impairment (cases) at enrollment and were matched 1:2 on sex, age (±2 years), and residential district with controls who were cognitively normal at the time of the evaluation. We used a standardized questionnaire to collect information on cognitive stimulating activities, lifestyle factors, demographics, and comorbidity. Cognitive stimulating activities included reading books or newspapers, playing cards or mahjong, using the Internet, socializing with neighbors, and community activities. Lifestyle factors included smoking, alcohol drinking, daily tea drinking, and regular exercise. We used logistic regression to assess the interaction between cognitive stimulating activities, lifestyle factors, and APOE ε4 allele carrier status (yes/no) on the risk of cognitive impairment. We tested for additive interaction by estimating relative excess risk (RERI) due to interaction and multiplicative interaction employing the p value of the interaction term of each lifestyle factor and APOE ε4 into the model. RESULTS: Four cognitive stimulating activities were associated with less cognitive impairment regardless of APOE ε4 status. Using the Internet (odds ratio [OR]: 0.53, 95% confidence interval [CI]: 0.30-0.95), daily tea drinking (OR: 0.79; 95% CI: 0.63-0.98), and regular exercise (OR: 0.78; 95% CI: 0.65-0.94) were associated with less cognitive impairment only in noncarriers. Multiplicative and additive interactions were found between community activities and APOE ε4 carrier status (multiplicative p value = 0.03; RERI 0.738, 95% CI: 0.201-1.275). CONCLUSION: The associations between cognitive activities and cognitive impairment were robust regardless of the APOE ε4 carrier status, while the associations between lifestyle factors and cognitive impairment varied by APOE ε4 carrier status.

Cigarettes, heated tobacco products and dual use: exhaled carbon monoxide, saliva cotinine and total tobacco consumed by Hong Kong tobacco users.

BACKGROUND: Independent studies on exhaled carbon monoxide (CO) and saliva cotinine levels in regular heated tobacco product (HTP) users, and how they compare with conventional cigarette (CC) smokers, are lacking. METHODS: A total of 3294 current users of CCs, HTPs or electronic cigarettes (ECs) from a household survey and a smoking hotspot survey were classified into seven groups: exclusive users of CCs, HTPs, ECs; dual users of CCs and HTPs, CCs and ECs, HTPs and ECs; and triple users. We measured exhaled CO level using the piCo Smokerlyzer (n=780) and saliva cotinine using NicAlert cotinine test strips (n=620). Among the seven groups, the differences in (1) CO and cotinine levels were examined using Kruskal-Wallis test, and (2) the average daily tobacco consumption in the past 30 days was examined using multivariable linear regression. RESULTS: Both exclusive and dual users of CCs had a higher CO level than exclusive HTP or EC users (p<0.05). Exhaled CO levels were similar between HTP and EC users, as were saliva cotinine levels among the seven groups. Compared with exclusive CC users, those who also used HTPs or ECs smoked fewer CCs (CCs+HTPs: adjusted coefficient -2.79, 95% CI -3.90 to -1.69; CCs+ECs: -1.34, 95% CI -2.34 to -0.34), but consumed more tobacco sticks equivalent in total (2.79 (95% CI 1.61 to 3.96); 1.95 (95% CI 0.79 to 3.12)). CONCLUSIONS: HTP or EC use showed lower exhaled CO but similar saliva cotinine levels compared with CC use. Dual users of CCs and HTPs/ECs smoked fewer CCs than exclusive CC users, but consumed more tobacco in total.

Changes in Tobacco Use in the Early Phase of Coronavirus Disease 2019 Pandemic in Hong Kong: A Qualitative Study.

INTRODUCTION: Changes in tobacco use and related personal and environmental factors amid the coronavirus disease 2019 (COVID-19) pandemic can be captured by qualitative studies, but they are few in non-Western populations. AIMS AND METHODS: We assessed the perceived links between tobacco use and COVID-19, and changes in the use of cigarettes, electronic cigarettes (ECs), and heated tobacco products (HTPs) in the early phase of the pandemic in Hong Kong, where lockdown was not implemented. Semi-structured telephone interviews were conducted from January to June 2021 in 95 participants (36 EC users, 28 HTP users, and 32 exclusive cigarette users). Transcriptions were coded using deductive and inductive approaches, and factors for changes were nested in the social-ecological model. RESULTS: Two-thirds of participants perceived their infection susceptibility was the same as never tobacco users, and 44.2% perceived more severe COVID-19 disease if infected. Amid the pandemic, tobacco use decreased overall but increased indoors for all three products. Increased tobacco use was mostly attributed to increased emotional distress, while decreases were attributed to various personal (health concerns) and environmental factors (e.g., COVID-19 regulations). Perceived convenience and lower costs were reasons for increased EC use. Limited access to HTPs was compensated by cigarette use. CONCLUSIONS: Many participants were unaware of the potential harm of tobacco use on COVID-19. Overall tobacco use decreased due to COVID-19 regulations, which may not be sustainable post-pandemic. Indoor consumption increased, supporting a comprehensive smoke-free policy that covers private indoor areas. Better cessation services targeting EC, HTP, and cigarette use are needed. IMPLICATIONS: Smokers need better awareness of the risk of tobacco use on COVID-19. Smoking cessation services can be improved by offering brief advice, strengthening advocacy against secondhand smoke, and covering EC and HTP use, highlighting their potential harms to users and others, and their risk of addiction and relapse to cigarette use.

Perception of heated tobacco products and support for regulations: a cross-sectional study in Hong Kong.

BACKGROUND: Hong Kong has proposed banning the sale of heated tobacco products (HTPs). Perceptions of reduced harms and effectiveness for quitting combustible cigarettes (CCs) of HTPs due to their promotions may erode public support for regulations. We assessed the associations between perceptions of HTPs and support for regulations in Hong Kong. METHODS: In two population-based landline surveys conducted in 2018-2019, 1985 respondents (51.4% male; 22.7% aged 60+ years) reported perceived relative harm of HTPs to CCs and effectiveness for quitting CCs, and support for five HTP regulations (ban on promotion and advertisements, use in smoke-free areas, sales to minors, registration before sale, sale licence) and a total ban on sale. Current and former smokers were oversampled due to low prevalence. Descriptive statistics were weighted to the general population. Associations were analysed, adjusting for sociodemographic characteristics, smoking status and ever HTP use. RESULTS: 27.4% (N=515) of respondents perceived HTPs as less harmful, and 18.8% (N=1299) perceived them as effective for quitting CCs. Support was generally high (at least one regulation, 99.1%, N=1959; all five regulations, 66.8%, N=1114; total ban, 63.5%, N=946). Perceptions of reduced harm were associated with lower support for all five regulations (adjusted risk ratio 0.85, 0.75 to 0.96) and a total ban on sale (0.58, 0.51 to 0.66). Results were similar for perceptions of effectiveness for quitting. CONCLUSIONS: Lower support for HTP regulations and a total ban on sale were associated with perceptions of reduced harm and effectiveness for quitting CCs of HTPs in Hong Kong.

A content analysis of heated tobacco product business in Hong Kong on Facebook.

Heated tobacco products (HTPs) are increasingly popular in Hong Kong (HK) even though they have not been formally launched and the sale of duty-not-paid tobacco sticks is illegal. We investigated how Facebook was used against regulations to sell HTPs in HK. We screened Facebook pages run by HTP businesses targeting HK users in June 2019 and included pages with over 300 "Likes" for inductive content analysis by coding their "About" descriptions and all posts including comments published since January 2017. HTPs included heating devices, accessories, and tobacco sticks. Various attributes were recorded including methods of customer inquiries (telephone, Instant Messaging [IM], address), business responses (comments or private messages, PM), and services provided (warranty/repair). Among 30 pages (50.9% of all 59 eligible pages with related information on HTPs), two-thirds provided phone numbers (66.7%), IM accounts (65.5%), and addresses (66.7%). Most pages sold heating devices (26, 86.7%) and accessories (22, 73.3%) with over 72% providing phone numbers, IM accounts, or addresses. Only 8 pages (26.7%) sold tobacco sticks with 75.0% providing telephone numbers but fewer provided IM accounts (62.5%) and addresses (50.0%). All pages responded using PMs and only 12.5% also used comments. Warranty/repair services were provided by 43.3% of the pages. We found Facebook pages were used as dedicated stores to promote and sell HTPs including heating devices, accessories, and even illicit tobacco sticks in HK, a non-official market.

Patterns of Perceived Harms and Benefits of the COVID-19 Outbreak in Hong Kong Adults: A Latent Profile Analysis.

The COVID-19 pandemic caused different types of harms and benefits, but the combined patterns of perceived harms and benefits are unclear. We aimed to identify the patterns of perceived harms and benefits of the COVID-19 outbreak and to examine their associations with socio-demographic characteristics, happiness, and changes in smoking and drinking. A population-based cross-sectional online survey was conducted in May 2020 on Hong Kong adults (N = 4520). Patterns of perceived harms and benefits of COVID-19 were identified using latent profile analysis. Their associations with socio-demographic characteristics, happiness, and changes in smoking and drinking were examined using multinomial logistic regression. We identified three distinct patterns: indifferent (66.37%), harm (13.28%), and benefit (20.35%). Compared with the indifferent subgroup, the harm subgroup was younger, less happy, and had increased drinking, and hence might be at higher risk, whereas the benefit subgroup was more likely to be female, live with one or more cohabitants, have postsecondary education, be happier, and have decreased drinking, and could be more adaptive. Future studies can target the harm subgroup to facilitate their positive adjustments.

Changes in tobacco use at the early stage of the COVID-19 pandemic: Results of four cross-sectional surveys in Hong Kong.

INTRODUCTION: Changes in tobacco use since the COVID-19 outbreak differed by countries and little is known about changes in the use of specific tobacco products. METHODS: We analyzed data from four cross-sectional telephone/online surveys from April to June 2020 to investigate such changes since the 1st and 2nd wave outbreaks (February to April 2020) in Hong Kong. The respondents were 1595 adults (83.2% male) who used tobacco before the COVID-19 outbreak from our previous intervention study and surveys. We investigated the changes in tobacco use, intention to quit and quit attempts during the outbreak. RESULTS: About two-thirds (65.3%) of respondents reported no change in overall tobacco use, while 23.1% used less (including cessation) and 11.6% used more, resulting in a net decrease of 11.5 percentage points. A greater net decrease was observed for cigarettes (14.3% points) than heated tobacco products (HTPs, 3.3% points) and electronic cigarettes (e-cigarettes, 2.5% points). Decreased use was mainly due to the more extended stay at home (63.2%), health considerations (52.6%) and mask-wearing (47.4%), while increased use was for passing time (75.0%) and releasing stress (46.4%). Eight percent of cigarette, HTP and e-cigarette users reported a higher intention to quit since the pandemic outbreak. Nineteen percent of tobacco users (176/948) attempted to quit during the pandemic. Only 2.9% (46/1569) were abstinent at the time of the survey. CONCLUSIONS: Overall tobacco use decreased after the first two waves of the COVID-19 outbreak in Hong Kong. A greater proportion of cigarette users decreased use than HTP and e-cigarette users. Given the different methods used in the four surveys, future studies should aim for a large and representative sample.

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.

Dose-Response Reduction in Risk of Nasopharyngeal Carcinoma From Smoking Cessation: A Multicenter Case-Control Study in Hong Kong, China.

BACKGROUND: Cigarette smoking is associated with nasopharyngeal cancer (NPC) risk. Whether quitting reduces the risk is unclear. We investigated the associations of NPC with duration of and age at quitting in an endemic region. METHODS: We investigated the associations between NPC and quitting in a multicenter case-control study in Hong Kong with 676 newly diagnosed NPC cases and 1,285 hospital controls between 2014 and 2017, using a computer-assisted self-administered questionnaire. Multivariable unconditional logistic regression yielded adjusted odds ratios (AORs) of NPC by quitting status, duration and age of quitting, combinations of duration and age of quitting, and quitting to smoking duration ratio, compared with current smoking. RESULTS: Quitting (AOR: 0.72; 95% CI: 0.53-0.98) and never smoking (0.73, 0.56-0.95) were associated with lower NPC risk. NPC risk decreased with (i) longer quitting duration (p < 0.01), reaching significance after 11-20 (0.62, 0.39-0.99) and 21+ years (0.54, 0.31-0.92) of quitting; (ii) younger quitting age (p = 0.01), reaching significance for quitting at <25 years (0.49, 0.24-0.97); and (iii) higher quitting to smoking duration ratio (p < 0.01), reaching significance when the ratio reached 1 (0.60, 0.39-0.93). Quitting younger (age <25) appeared to confer larger reductions (49% for ≤10 years of quitting, 50% for 11+ years) in NPC risk than quitting at older ages (25+) regardless of quitting duration (16% for ≤10 years, 39% for 11+ years). CONCLUSIONS: We have shown longer duration and younger age of quitting were associated with lower NPC risk, with dose-response relations. Our findings support including smoking as a cause of NPC. Stronger tobacco control measures and quitting services are needed to prevent NPC.

High Perceived Susceptibility to and Severity of COVID-19 in Smokers Are Associated with Quitting-Related Behaviors.

A growing body of evidence shows smoking is a risk factor for coronavirus disease (COVID-19). We examined the associations of quitting-related behaviors with perceived susceptibility to and severity of COVID-19 in smokers. We conducted a telephone survey of 659 community-based adult smokers (81.7% male) in Hong Kong, where there was no lockdown. Exposure variables were perceptions that smoking can increase the risk of contracting COVID-19 (perceived susceptibility) and its severity if infected (perceived severity). Outcome variables were quit attempts, smoking reduction since the outbreak of the pandemic, and intention to quit within 30 days. Covariates included sex, age, education, heaviness of smoking, psychological distress, and perceived danger of COVID-19. High perceived susceptibility and severity were reported by 23.9% and 41.7% of participants, respectively. High perceived susceptibility was associated with quit attempts (prevalence ratio (PR) 2.22, 95% CI 1.41-3.49), smoking reduction (PR 1.75, 95% CI 1.21-2.51), and intention to quit (PR 2.31, 95% CI 1.40-3.84). Perceived severity of COVID-19 was associated with quit attempts (PR 1.64, 95% CI 1.01-2.67) but not with smoking reduction or intention to quit. To conclude, the perceived susceptibility to and severity of COVID-19 in smokers were associated with quitting-related behaviors in current smokers, which may have important implications for smoking cessation amid the pandemic.

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.

Low vitamin D exposure and risk of nasopharyngeal carcinoma: Observational and genetic evidence from a multicenter case-control study.

BACKGROUND & AIMS: Little is known about the risk of nasopharyngeal carcinoma (NPC) in relation to vitamin D exposure. The aim of this study was to examine the associations of NPC risk with serum level of 25-hydroxyvitamin D (25OHD) and genetic predicted 25OHD, and potential effect modification by several putative risk factors of NPC. METHODS: Our multicenter case-control study in Hong Kong recruited 815 NPC cases and 1502 frequency-matched (by sex and age) hospital controls from five major regional hospitals, and recruited 299 healthy subjects from blood donation centers (2014-2017). Circulating level of 25-hydroxyvitamin D (25OHD) and genetic predicted 25OHD (rs12785878, rs11234027, rs12794714, rs4588 and rs6013897) were measured by validated enzyme immunoassay and the iPLEX assay on the MassARRAY System, respectively. Data were also collected on demographics, lifestyle factors, ultraviolet radiation exposure, and potential confounders using a computer-assisted, self-administered questionnaire with satisfactory test-retest reliability. Unconditional logistic regression models were used to estimate ORs and 95% CIs. RESULTS: Despite no significant association of NPC risk with circulating 25OHD and genetic predicted 25OHD, there was evidence for an inverse association in participants with normal body mass index (between 18.5 and 27.5) across categories of 25OHD (Ptrend = 0.003), and a positive association in those with low socioeconomic status across categories based on the genetic score (Ptrend = 0.005). In addition, risk of NPC diagnosed at an early stage was higher for genetically lower 25OHD level (adjusted OR = 3.09, 95% CI = 1.04-9.21, Ptrend = 0.022). CONCLUSIONS: Findings of this first comprehensive study to investigate the positive association of NPC risk with vitamin D deficiency need to be confirmed and be best interpreted with results of further similar studies. Our findings may inform possible etiological mechanisms of the associations with several putative risk/protective factors of NPC.

Characterization of Respiratory Symptoms Among Youth Using Heated Tobacco Products in Hong Kong.

Importance: Heated tobacco products (HTPs) are promoted as less harmful than combustible cigarettes but epidemiological evidence is scarce, especially in youth. Objective: To investigate the associations of persistent respiratory symptoms with HTP use, cigarette use, and dual use among Hong Kong youth. Design, Setting, and Participants: This was a territorywide cross-sectional school-based survey conducted from October 2018 to July 2019 using an anonymous questionnaire. Schools were randomly invited from a proportionate stratified sample in all 18 districts of Hong Kong. Poisson regression models using generalized estimating equations yielded adjusted prevalence ratios (APRs) of respiratory symptoms in (1) former and current HTP (vs never) users in the whole sample and stratified by cigarette use status and (2) exclusive HTP and dual users vs exclusive cigarette users. Statistical analysis was performed from October 2020 to March 2021. Exposures: Former and current use of cigarettes, HTPs, e-cigarettes, and other tobacco products. Main Outcomes and Measures: Respiratory symptoms for 3 consecutive months in the past 12 months. Results: The study included 33 627 students with a mean (SD) age of 14.8 (1.9) years; 51.3% (18 171) were boys. Respiratory symptoms were reported by 16.3% (n = 5549) of all students, 29.3% (n = 226) of current users of e-cigarettes, 31.2% (n = 314) of current users of cigarettes, and 33.5% (n = 179) of current users of HTPs. Respiratory symptoms were associated with former (APR, 1.30; 95% CI, 1.06-1.59) and current (APR, 1.59; 95% CI, 1.23-2.06) vs never HTP use and current vs never cigarette use (APR, 1.50; 95% CI, 1.30-1.74) after adjusting for various tobacco use. Associations between respiratory symptoms and current vs never HTP use were observed in never (APR, 1.88; 95% CI, 1.36-2.59) and former (APR, 2.15; 95% CI, 1.12-4.12) cigarette users, but not in current cigarette users (APR, 1.24; 95% CI, 0.97-1.59). Respiratory symptoms were associated with exclusive ever HTP use (APR, 1.46, 95% CI, 1.15-1.86) and ever dual use (APR, 1.29; 95% CI, 1.08-1.54) vs exclusive ever cigarette use. There was no association between exclusive current HTP (vs cigarette) use and respiratory symptoms (1.40; 95% CI, 0.93-2.11). Conclusions and Relevance: This cross-sectional study found that former and current HTP use were associated with persistent respiratory symptoms among youth, especially among never and former cigarette users. Respiratory symptoms were more prevalent in ever exclusive HTP users and ever dual users than ever exclusive cigarette users. These findings suggest that using HTPs instead of cigarettes may not reduce health risks.

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.

Smoking and nasopharyngeal cancer: individual data meta-analysis of six prospective studies on 334 935 men.

BACKGROUND: The role of smoking in nasopharyngeal carcinoma (NPC) remains uncertain, especially in endemic regions. We conducted an individual participant data (IPD) meta-analysis of prospective cohort studies to investigate the associations between smoking exposure and risk of NPC. METHODS: We obtained individual participant data of 334 935 male participants from six eligible population-based cohorts in NPC-endemic regions, including two each in Guangzhou and Taiwan, and one each in Hong Kong and Singapore. We used one- and two-stage approaches IPD meta-analysis and Cox proportional hazard models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of NPC for smoking exposure adjusting for age and drinking status. RESULTS: During 2 961 315 person-years of follow-up, 399 NPC evens were ascertained. Risks of NPC were higher in ever versus never smokers (HRone-stage = 1.32, 95% CI = 1.07-1.63, P = 0.0088; HRtwo-stage = 1.27, 1.01-1.60, 0.04). These positive associations appeared to be stronger in ever smokers who consumed 16+ cigarettes/day (HRone-stage = 1.67, 95% CI = 1.29-2.16, P = 0.0001), and in those who started smoking at age younger than 16 (2.16, 1.33-3.50, 0.0103), with dose-response relationships (P-values for trend = 0.0028 and 0.0103, respectively). Quitting (versus daily smoking) showed a small reduced risk (stopped for 5+ years: HRone-stage = 0.91, 95% CI = 0.60-1.39, P = 0.66; for former smokers: HRtwo-stage = 0.84, 0.61-1.14, 0.26). CONCLUSIONS: This first IPD meta-analysis from six prospective cohorts in endemic regions has provided robust observational evidence that smoking increased NPC risk in men. NPC should be added to the 12-16 cancer sites known to be tobacco-related cancers. Strong tobacco control policies, preventing young individuals from smoking, would reduce NPC risk in endemic regions.

Dietary fiber intake from fresh and preserved food and risk of nasopharyngeal carcinoma: observational evidence from a Chinese population.

BACKGROUND: The role of dietary fiber intake on risk of nasopharyngeal carcinoma (NPC) remains unclear. We examined the associations of dietary fiber intake on the risk of NPC adjusting for a comprehensive list of potential confounders. METHODS: Using data from a multicenter case-control study, we included 815 histologically confirmed NPC incident cases and 1502 controls in Hong Kong, China recruited in 2014-2017. Odds ratios (ORs) of NPC (cases vs controls) for dietary fiber intake from different sources at different life periods (age 13-18, age 19-30, and 10 years before recruitment) were evaluated using unconditional logistic regression, adjusting for sex, age, socioeconomic status, smoking and drinking status, occupational hazards, family history of cancer, salted fish, and total energy intake in Model 1, Epstein-Barr virus viral capsid antigen serological status in Model 2, and duration of sun exposure and circulating 25-hydroxyvitamin D in Model 3. RESULTS: Higher intake of total dietary fiber 10 years before recruitment was significantly associated with decreased NPC risk, with demonstrable dose-response relationship (P-values for trend = 0.001, 0.020 and 0.024 in Models 1-3, respectively). The adjusted ORs (95% CI) in the highest versus the lowest quartile were 0.51 (0.38-0.69) in Model 1, 0.48 (0.33-0.69) in Model 2, and 0.48 (0.33-0.70) in Model 3. However, the association was less clear after adjustment of other potential confounders (e.g. EBV) in the two younger periods (age of 13-18 and 19-30 years). Risks of NPC were significantly lower for dietary fiber intake from fresh vegetables and fruits and soybean products over all three periods, with dose-response relationships observed in all Models (P-values for trend for age 13-18, age 19-30 and 10 years before recruitment were, respectively, 0.002, 0.009 and 0.001 for Model1; 0.020, 0.031 and 0.003 for Model 2; and 0.022, 0.037 and 0.004 for Model 3). No clear association of NPC risk with dietary fiber intake from preserved vegetables, fruits and condiments was observed. CONCLUSION: Our study has shown the protective role of dietary fiber from fresh food items in NPC risk, but no association for total dietary fiber intake was observed, probably because total intake also included intake of preserved food. Further studies with detailed dietary information and in prospective settings are needed to confirm this finding, and to explore the possible underlying biological mechanisms.