Prevalence of and Factors Associated With Tobacco Dependence Among Adolescents Aged 12-16 Years Who Were Currently Smoking Tobacco in 125 Countries or Territories, 2012-2019.

Objectives. To examine the global prevalence of and factors associated with tobacco dependence among adolescents who are currently smoking. Methods. We obtained 2012 to 2019 Global Youth Tobacco Survey data on 67 406 adolescents aged 12 to 16 years from 125 countries or territories (hereafter countries). Those with tobacco dependence were defined as current smokers who felt a strong desire to smoke again within 24 hours after smoking or who had ever smoked or felt like smoking first thing in the morning. Results. The global prevalence of tobacco dependence among adolescents who were currently smoking was 38.4% (95% confidence interval [CI] = 34.0, 42.7). The prevalence was highest in high-income countries (49.8%; 95% CI = 47.0, 52.6) and lowest in lower-middle-income countries (31.2%; 95% CI = 26.9, 35.4). Secondhand smoke exposure, parental smoking, smoking among closest friends, tobacco advertisement exposure, and offers of free tobacco products were positively associated with tobacco dependence. Conclusions. Nearly 40% of adolescents who are currently smoking have tobacco dependence worldwide. Public Health Implications. Our findings emphasize the need to develop tobacco control interventions to prevent experimentation from progressing to regular smoking among adolescents who are currently smoking tobacco. (Am J Public Health. 2023;113(8):861-869. https://doi.org/10.2105/AJPH.2023.307283).

Proportions of and trends in exposure to pro-tobacco and anti-tobacco advertisements among young adolescents aged 12-16 years in 142 countries and territories, 1999-2018: an analysis of repeated cross-sectional surveys.

BACKGROUND: The proportions and trends in exposure to pro-tobacco and anti-tobacco advertisements among young people remain unknown globally. We determined recent (2010-18) proportions of exposure to pro-tobacco and anti-tobacco advertisements among young adolescents and their secular trends from 1999 to 2018. METHODS: In this analysis of repeated cross-sectional surveys, we used the most recent data from 142 countries and territories (hereafter referred to as countries) collected between Jan 1, 2010, and Dec 31, 2018, comprising 710 191 participants, to assess the proportions of exposure to pro-tobacco and anti-tobacco advertisements among young adolescents aged 12-16 years. Data from 120 countries that had performed two or more Global Youth Tobacco Surveys between Jan 1, 1999, and Dec 31, 2018, comprising 1 482 031 participants, were used to assess trends in the proportions of exposure to pro-tobacco and anti-tobacco advertisements over time. A χ2 test analysis was used for proportion comparisons between subgroups. Exposure to pro-tobacco and anti-tobacco advertisements were calculated as proportions using sampling weights, strata, and primary sampling units. FINDINGS: The most recent global proportion of past 30-day exposure to tobacco advertisements among young adolescents was 433 585 (64·6%) of 710 191 (95% CI 63·5-65·7; all final percentages were weighted) for messages on electronic media, 206 766 (33·1%) of 710 191 (31·9-34·4) for exposure at the point of sale, and 63 385 (10·2%) of 710 191 (9·7-10·6) for owning something with a tobacco brand logo. The most recent global proportion of exposure to anti-tobacco advertisements was 431 862 (63·6%) of 710 191 (62·3-64·9) for messages on electronic media and 227 658 (34·1%) of 710 191 (32·8-35·3) for exposure to gathering activities. The majority of included countries showed a decreasing trend in exposure to tobacco advertisements (111 [93%] of 120) and anti-tobacco advertisements (110 [92%] of 120) between 1999 and 2018. INTERPRETATION: Among young adolescents, exposure to tobacco advertisements remains high, and exposure to anti-tobacco advertisements is not high enough. The proportion of young adolescents exposed to pro-tobacco and anti-tobacco advertisements had decreased over time in the majority of included countries. These findings underscore the importance of strict implementation of regulation on tobacco control including strengthening anti-tobacco marketing and prohibiting tobacco marketing. FUNDING: Youth Team of Humanistic and Social Science of Shandong University. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Trends in Exposure to Secondhand Smoke Among Adolescents in China From 2013-2014 to 2019: Two Repeated National Cross-sectional Surveys.

BACKGROUND: It is well-known that secondhand smoke exposure in childhood or adolescence is positively associated with morbidity and mortality. However, less is known about the current status of and most recent trends in secondhand smoke exposure among adolescents in China. OBJECTIVE: We aimed to assess recent changes in the prevalence of secondhand smoke exposure among adolescents in China using nationally representative data. METHODS: We used data from 2 repeated national cross-sectional surveys conducted in 2013-2014 and 2019. A total of 155,117 students (median age 13.5 years) in 2013-2014 and 147,270 students (median age 13.1 years) in 2019 were included in this study. Sociodemographic factors and secondhand smoke exposure information were collected via a standardized questionnaire. Exposure was defined as secondhand smoke exposure ≥1 day during the past 7 days at home or in public places. Other frequencies of secondhand smoke exposure (ie, ≥3 days, ≥5 days, and every day) during the past 7 days were also assessed. The weighted prevalence of secondhand smoke exposure was calculated according to the complex sample design for surveys. RESULTS: The prevalence of secondhand smoke exposure in any place (home or public places ≥1 day during the past 7 days) decreased from 2013-2014 (72.9%, 95% CI 71.5%-74.3%) to 2019 (63.2%, 95% CI 62%-64.5%), as did exposure at home (2013-2014: 44.4%, 95% CI 43.1%-45.7%; 2019: 34.1%, 95% CI 33.1%-35.2%) and in public places (2013-2014: 68.3%, 95% CI 66.9%-69.6%; 2019: 57.3%, 95% CI 56%-58.6%). The prevalence of secondhand smoke exposure decreased with increased gross domestic product per capita in each of the 2 survey years irrespective of exposure frequency or location. The prevalence of exposure at other frequencies (ie, ≥3 days, ≥5 days, or every day during the past 7 days) also decreased in any place, at home, and in public places. Secondhand smoke exposure was associated with higher school grade level (ninth vs seventh grade: odds ratio [OR] 1.76, 95% CI 1.68-1.84), gender (boys vs girls: OR 1.18, 95% CI 1.15-1.22), urban status (urban vs rural: OR 1.10, 95% CI 1.01-1.19), and cigarette smoking (yes vs no: OR 6.67, 95% CI 5.83-7.62). CONCLUSIONS: Although the prevalence of secondhand smoke exposure among Chinese adolescents declined from 2013-2014 to 2019, it remains unacceptably high. More effective strategies and stronger action are needed in China to further, and dramatically, curb secondhand smoke exposure among adolescents.

Association between secondhand smoke exposure in indoor public places and carotid intima media thickness in children and adolescents / 中国学校卫生

Objective@#To examine the association between secondhand smoke exposure (SHS) in indoor public places and carotid intima media thickness (cIMT) in children and adolescents, so as to provide guidance for the prevention of early abnormal vascular architecture.@*Methods@#The data were obtained from the second follow up of the Children Cardiovascular Health Cohort Study conducted from November to December 2021. A total of 1 297 children and adolescents for who completed data relating to sex, age, cIMT, physical examinations, questionnaires variables and blood biochemical indices, were included for analysis. Linear regression analysis was performed to examine trends in the levels of cIMT with exposure to SHS in indoor public places. Multiple linear regression analysis was carried out to assess the association between SHS exposure in indoor public places and cIMT after adjustment for potential covariates.@*Results@#During the previous 7 days, 407 (31.4%) children and adolescents were exposed to SHS in indoor public places for 1-2 days, 86 (6.6%) for 3-4 days, and 82 (6.3%) for ≥5 days. The levels of cIMT in youth increased on different models, with the duration of SHS exposure during the previous 7 days ( t=3.30, 3.05, 2.87, P <0.05). After adjusting for various covariates, the cIMT values of children and adolescents were[0 day:(551.5±29.3) μm, 1-2 days:(554.0±28.6) μm, 3-4 days:(557.0±27.7) μm, ≥5 days:(559.4±27.5) μm]. Compared to those who were not exposed to SHS in indoor public places during the previous 7 days, those exposed for ≥5 days had significantly higher cIMT levels ( β=7.91, 95%CI=1.47-14.34, P <0.05).@*Conclusion@#Among children and adolescents, exposure to SHS in indoor public places remains high and is significantly associated with cIMT. The findings highlight the need for stricter regulation and tobacco control policies to provide healthy smoke free environments for children and adolescents, and to reduce the risk of early abnormal vascular architecture.

Prevalence of waterpipe smoking and its associated factors among adolescents aged 12-16 years in 73 countries/territories.

Introduction: To describe the recent prevalence of, and trends in, waterpipe smoking and to examine its associated factors among adolescents aged 12-16 years in 73 countries/territories (hereafter "countries"). Methods: Data from 72 countries that had conducted a Global Youth Tobacco Survey (GYTS) in 2010-2019 and from the National Youth Tobacco Survey in the United States in 2019 were used to assess the recent prevalence of waterpipe smoking and to examine its associated factors among adolescents aged 12-16 years. Data from 38 countries that had carried out at least 2 surveys from 2000 to 2019 were used to determine trends in the prevalence of waterpipe smoking among adolescents. Results: The recent prevalence of current waterpipe smoking (on 1 day during the past 30 days) among adolescents was 6.9% (95%CI 6.4-7.5). The prevalence was highest in the European region (10.9%, 9.9-11.8) and Eastern Mediterranean region (10.7%, 9.5-11.9), but lowest in the Western Pacific region (1.9%, 1.4-2.4). The prevalence of current waterpipe smoking increased or remained unchanged in 19 (50%) of 38 countries, but decreased in the remaining 19 countries (50%). Parental smoking, closest friends' smoking, secondhand smoke exposure, tobacco advertisement exposure, not being taught the dangers of smoking, particularly cigarette smoking, were positively associated with adolescent waterpipe smoking. Discussion: Waterpipe smoking among adolescents remains a major public health issue worldwide, especially in the regions of Europe and the Eastern Mediterranean. Effective prevention and control strategies and measures are needed to curb the epidemic of adolescent waterpipe smoking.

Cigarette access and purchase patterns among adolescent smokers aged 12-16 years in 140 countries/territories, Global Youth Tobacco Survey 2010-2018.

Background: Few studies have examined access to cigarettes among adolescents. To address this, we aimed to examine cigarette access and purchase patterns among adolescent cigarette smokers based on the most recent data from the Global Youth Tobacco Surveys (GYTS). Methods: We used the most recent school-based GYTS data (2010-2018) on 49 856 adolescent cigarette smokers aged 12-16 years in 140 countries/territories (hereafter "countries") to examine cigarette access and purchase patterns among adolescent smokers. Results: Over half (51.2%) of adolescent smokers bought cigarettes from commercial vendors (ie, stores/shops/street vendors/kiosks) and one-third of smokers (32.7%) got cigarettes from private persons (ie, peers or adults). Males (vs females), older adolescents (vs younger ones), and adolescent smokers from low-income countries (vs those from middle- or high-income countries) were more likely to buy cigarettes from commercial vendors. Younger adolescents (vs older ones) and adolescent smokers from low-income countries (vs those from middle- or high-income countries) were more likely to get cigarettes from private persons. As many as 39.6% of adolescent smokers reported that they were not denied buying cigarettes from commercial vendors due to age restrictions, especially among males (vs females), among older adolescents (vs younger ones), and among adolescent smokers from upper-middle-income or high-income countries (vs those from low-income countries). Purchasing cigarettes as single sticks was more likely to occur in males (vs females), in older adolescents (vs younger ones), and in adolescent smokers from low-income countries (vs those from upper-middle-income or high-income countries), with inverse findings for purchasing cigarettes in full packs. Conclusions: Adolescent smokers often obtained cigarettes from commercial vendors or private persons. Additionally, adolescent smokers often purchased cigarettes in packs and as individual sticks. These findings emphasize the need to strengthen measures to reduce the supply of cigarettes to minors.

Prevalence and trend of smokeless tobacco use and its associated factors among adolescents aged 12-16 years in 138 countries/territories, 1999-2019.

BACKGROUND: Smokeless tobacco use is popular in some regions worldwide, but it receives less attention compared to cigarette smoking. We aimed to estimate the recent prevalence of, and trends in, smokeless tobacco use and to examine its associated factors among adolescents aged 12-16 years in 138 countries/territories (hereafter "countries") from 1999 to 2019. METHODS: Data from the Global Youth Tobacco Survey conducted in 138 countries in 2010-2019 and the National Youth Tobacco Survey conducted in the United States in 2019 were used to calculate the prevalence of current smokeless tobacco use and investigate its associated factors among adolescents aged 12-16 years. We also assessed the trend in the prevalence of smokeless tobacco use in 100 countries that had conducted more than one survey from 1999 to 2019. RESULTS: The overall prevalence of current smokeless tobacco use was 4.4% (95% confidence interval [CI] 4.0-4.9), with 5.7% (5.1-6.3) for boys, 3.1% (2.6-3.5) for girls, 3.9% (3.5-4.4) for adolescents aged 12-14 years and 5.4% (4.8-5.9) for those aged 15-16 years. The prevalence was highest in the South-East Asian region (6.1%, 4.4-7.7) and lowest in the Western Pacific region (2.0%, 1.7-2.4). The prevalence of smokeless tobacco use decreased in 57 of 100 countries, increased in 32 countries, and remained unchanged in 11 countries. Current cigarette smoking (odds ratio [OR]=2.00, 95% CI=1.68-2.39), other tobacco product use (OR=6.03, 95% CI=4.92-7.40), tobacco advertisement exposure (OR=1.44, 95% CI=1.19-1.74), being offered free tobacco products (OR=2.01, 95% CI=1.66-2.42), and not being taught about dangers of smoking (OR=1.28, 95% CI=1.09-1.50) were all positively associated with current smokeless tobacco use. CONCLUSIONS: Smokeless tobacco use among adolescents remains a public health concern worldwide. Although the prevalence among adolescents decreased in most countries, it remains high especially in the South-East Asian region. More strict and effective strategies and measures are needed to further curb the smokeless tobacco use among adolescents.

Long non-coding RNA: Multiple effects on the differentiation, maturity and cell function of dendritic cells.

Long non-coding RNAs (LncRNAs), lacking protein-coding function, modulate immune function by regulating the expression of genes or the function of protein molecules. They participate in epigenetic regulation, interfere with downstream gene transcription acting as a molecular sponge to affect miRNA function, and can combine with proteins to form nucleic acid protein complexes that affect protein function or cell location to regulate genes and regulate immune function. LncRNAs are differentially expressed in immune cells. They affect the maturity, differentiation and activation of immune cells and regulate cytokine release and immune phenotype. They are closely related to immune tolerance and cell migration. Dendritic cells (DCs) are important immune cells with the most robust antigen-presenting function, and have irreplaceable roles in human innate immunity and adaptive immunity. Emerging evidence over the past few years has suggested that LncRNAs influence the differentiation and maturation of DCs and serve as a critical role in the cell phenotype and immune function of DCs. To further understand the role of LncRNAs in the occurrence and development of DC-related diseases, we elaborated the role of LncRNAs in DC immune function, including antigen presentation, T cell activation and proliferation, DC migration. Furthermore, we summarized the impact of pathological factors (tumors, inflammation, autoimmune disease, viral infection) and physiological factors (e.g., age) on the LncRNAs in DCs, and how the changed LncRNAs altered the function and behavior of DCs resulting from the intervention. We hope this review give us have a better understanding of multiple effects of LncRNA on cell function in DCs.

Sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population.

BACKGROUND: Sleep deprivation may cause depressive disorders in both children and adults. However, the effects of sleep duration change from childhood to adulthood on adult depressive disorders are poorly documented. Using the China Family Panel Study (CFPS) data, we aimed to examine the association between sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population. METHODS: Data were from 1172 children aged 10-15 years in 2010 who were followed up through 2018 based on the nationally representative and population-based CFPS. According to sleep duration in childhood and early adulthood, the sleep duration change was categorized into four groups: persistently insufficient sleep, sleep duration loss, sleep duration gain and persistently sufficient sleep. RESULTS: After adjustment for potential covariates, compared with individuals with persistently sufficient sleep duration, those with sleep duration loss (OR = 1.98, 95% CI = 1.14-3.46) and persistently insufficient sleep (OR = 2.35, 95% CI = 1.43-3.88) had higher odds of depressive disorders in adulthood. In contrast, the odds of adult depressive disorders did not significantly increase in those with sleep duration gain (OR = 1.46, 95% CI = 0.88-2.41). LIMITATIONS: Information on sleep duration was obtained through a questionnaire; the sample size of this study was not large; the generalizality of our findings to other populations should be caucious. CONCLUSION: Persistently insufficient sleep duration and sleep duration loss from childhood to adulthood were associated with higher odds of adult depressive disorders, while those who were able to change their sleep duration from insufficient status to sufficient status didn't have an increased odds of adult depressive disorders.

Sex and macroeconomic differences and trends in early attempts at cigarette smoking among adolescents: findings from 147 countries.

BACKGROUND: Most tobacco users initiate smoking during adolescence. Little is known about the global prevalence and trends in early cigarette smoking among adolescents. This study aimed to evaluate the prevalence of early attempts at cigarette smoking and its change trends among young adolescents. METHODS: We used data from the Global Youth Tobacco Surveys on adolescents aged 12-16 years, comprising 456,634 participants from 147 countries between 2006 and 2018, to estimate the prevalence of early attempts at cigarette smoking and age distribution at attempt by sex, country income, purchasing power parity (PPP) per capita, and WHO region. We assessed the average annual rate of reduction (AARR) in the prevalence of attempts at cigarette smoking before 12 years of age in 70 countries that had data from three or more surveys completed between 1999 and 2018. RESULTS: The average prevalence of early attempts at cigarette smoking was 12.2% (95% CI: 10.9-13.5) for boys and 6.7% (95% CI: 5.8-7.6) for girls, with the highest prevalence of 17.4% for boys and 10.7% for girls in the European region. Along with the growth of the national economy, the prevalence of early attempts at cigarette smoking gradually increased in both sexes. A total of 22.9% and 30% of countries had a negative change in AARR for boys and for girls, respectively. The countries with an upward prevalence were mainly located in the Eastern Mediterranean, Southeast Asia, and African regions. The age distribution at first cigarette smoked did not differ substantially between sexes. Notably, the age at first cigarette smoked of 10.7 years for girls was significantly earlier than that of 11.8 years for boys in low-income countries. Among cigarette-smoking adolescents, the average percentage of girls reporting smoking their first cigarette at an age <12 years was 55.7% in Q1 for PPP quintiles, 46.5% in Q2, 40.3% in Q3, 38.4% in Q4, and 34.6% in Q5, and the corresponding prevalence for boys was 46.0% in Q1, 42.8% in Q2, 42.9% in Q3, 43.5% in Q4, and 41.1% in Q5. CONCLUSIONS: The global prevalence of early attempts at cigarette smoking among adolescents was substantial, with differences by sex and macroeconomic situation, and our findings stress that interventions and policies targeting the first smoking experience are required to prevent the initiation of tobacco use among early adolescents, especially girls in low-income countries.

Daytime napping and cardiovascular risk factors, cardiovascular disease, and mortality: A systematic review.

Associations between night sleep duration and cardiovascular risk factors in adults have been well documented. However, the associations for daytime napping remain unclear. In this review, six databases were searched for eligible publications to April 8, 2022. A total of 11 articles were identified for umbrella review on the association of daytime napping with diabetes, metabolic syndrome (MetS), cardiovascular disease (CVD), and mortality in adults, 97 for systematic review on the association with CVD and several CVD risk factors. Our umbrella review showed that the associations of daytime napping with diabetes, MetS, CVD, and mortality in most meta-analyses were mainly supported by weak or suggestive evidence. Our systematic review showed that long daytime napping (≥1 h/d) was associated with higher odds of several CVD risk factors, CVD, and mortality, but no significant association was found between short daytime napping and most of the abovementioned outcomes. Our dose-response meta-analyses showed that daytime napping <30 min/d was not significantly associated with higher odds of most CVD risk factors and CVD among young and middle-aged adults. However, among older adults aged >60 years, we observed significant dose-response associations of daytime napping with higher odds of diabetes, dyslipidemia, MetS, and mortality starting from 0 min/d.

Prevalence of E-Cigarette Use and Its Associated Factors Among Youths Aged 12 to 16 Years in 68 Countries and Territories: Global Youth Tobacco Survey, 2012‒2019.

Objectives. To describe the recent global prevalence of e-cigarette use and to investigate its associated factors among youths aged 12 to 16 years in 68 countries and territories (hereafter "countries"). Methods. We analyzed 485 746 youths aged 12 to 16 years from the population-based cross-sectional Global Youth Tobacco Survey conducted in 67 countries between 2012 and 2019 and the 2019 National Youth Tobacco Survey in the United States. We defined past-30-day e-cigarette use as using e-cigarettes on 1 or more days during the past 30 days. Results. The global prevalence of past-30-day e-cigarette use among youths was 9.2%, ranging from 1.9% in Kazakhstan to 33.2% in Guam. Maternal smoking (adjusted odds ratio [AOR] = 1.40; 95% confidence interval [CI] = 1.29, 1.52), paternal smoking (AOR = 1.13; 95% CI = 1.07, 1.19), secondhand smoke exposure (AOR = 1.74; 95% CI = 1.64, 1.84), youth cigarette smoking (AOR = 7.18; 95% CI = 6.84, 7.54), and youth other tobacco use (AOR = 3.88; 95% CI = 3.62, 4.15) were positively associated with e-cigarette use. Conclusions. E-cigarette use was moderately frequent among youths aged 12 to 16 years globally. Several important factors were associated with youth e-cigarette use. Public Health Implications. Our findings highlight the need for countries worldwide to develop policies to address e-cigarette use among youths. (Am J Public Health. 2022;112(4):650-661. https://doi.org/10.2105/AJPH.2021.306686).

Leisure sedentary time and suicide risk among young adolescents: Data from 54 low- and middle-income countries.

BACKGROUND: The dose-response association between sedentary time and suicidal ideation and planning among adolescents is unclear. This study examined the association between leisure sedentary time and suicidal ideation, planning and attempts among adolescents in low- and middle-income countries (LMICs). METHODS: We used the most recent data (2009-2016) from the Global School-based Student Health Survey (GSHS) in 54 LMICs. Leisure sedentary time and suicidal ideation, planning and attempts were assessed using a standardized questionnaire. A total of 146,345 young adolescents aged 12-15 years were included. RESULTS: Among adolescents in the 54 LMICs, the prevalence of suicidal ideation was 14.8%, planning was 14.5%, and attempts was 13.0%. Compared with those who had less than 1 h/day of sedentary time, those who had 3, 4 h/day sedentary time were at higher odds ratio (OR) of suicidal ideation OR=1.21 (95% confidence interval (CI) =1.14-1.29), planning OR=1.15 (95%CI=1.07-1.22) and attempts OR=1.17 (95%CI=1.09-1.26), and those who had more than 8 h/day sedentary time were at OR=1.58 (95%CI=1.44-1.72), OR=1.44 (95%CI=1.31-1.58) and OR=1.27 (95%CI=1.16-1.40), respectively. LIMITATIONS: Suicidal behaviors and sedentary time were assessed by a self-reported questionnaire, which might be prone to recall bias. CONCLUSIONS: Higher amounts of leisure sedentary time are associated with suicidal ideation, planning and attempts among adolescents. Adolescents should spend less than 2 h/day of their sedentary time to reduce the likelihood of suicide.

Global trends in the prevalence of secondhand smoke exposure among adolescents aged 12-16 years from 1999 to 2018: an analysis of repeated cross-sectional surveys.

BACKGROUND: Secondhand smoke exposure can cause morbidity and premature mortality. However, the global prevalence of, and trends in, secondhand smoke exposure among adolescents are poorly documented. We aimed to assess the prevalence of, and trends in, secondhand smoke exposure among adolescents from 1999 to 2018. METHODS: We did an analysis of the most recent data from the Global Youth Tobacco Survey (GYTS), a nationally representative, self-administered, school-based cross-sectional survey of tobacco use and related factors among adolescents aged 12-16 years worldwide. Data from 142 countries and territories that had done a GYTS between 2010 and 2018, comprising 711 366 participants, were used to assess the prevalence of secondhand smoke exposure. Data from 131 countries and territories that had done two or more surveys between 1999 and 2018, comprising 1 405 458 participants, were used to assess trends in secondhand smoke exposure. The frequency of secondhand smoke exposure at home, in public places, or in any place was defined as follows, based on students' responses: 1 or more days, 3 or more days, 5 or more days, or daily during the past 7 days. FINDINGS: Based on the most recent surveys done in 142 countries between Jan 1, 2010, and Dec 31, 2018, the global prevalence of secondhand smoke exposure in any place was 62·9% (95% CI 61·7-64·1) on 1 or more days, 51·0% (49·8-52·1) on 3 or more days, 40·1% (38·9-41·2) on 5 or more days, and 32·5% (31·5-33·6) daily during the past 7 days. The prevalence of secondhand smoke exposure at home was 33·1% (95% CI 32·1-34·1) on 1 or more days, 20·1% (19·3-20·9) on 3 or more days, 14·9% (14·2-15·7) on 5 or more days, and 12·3% (11·7-13·0) daily during the past 7 days; and in public places the prevalence of secondhand smoke exposure was 57·6% (56·4-58·8) on 1 or more days, 43·4% (42·2-44·6) on 3 or more days, 30·3% (29·2-31·5) on 5 or more days, and 23·5% (22·5-24·5) daily during the past 7 days. Between Jan 1, 1999, and Dec 31, 2018, the prevalence of secondhand smoke exposure (on ≥1 day during the past 7 days) in any place decreased in 57 (43·5%) of 131 countries, increased in 27 (20·6%), and remained unchanged in 47 (35·9%). Although the prevalence of secondhand smoke exposure at home decreased in 86 (65·6%) countries, the prevalence in public places did not change in 46 (35·1%) countries and increased in 40 (30·5%). INTERPRETATION: Secondhand smoke exposure among adolescents remains a serious public health challenge worldwide. Although the prevalence of secondhand smoke exposure at home decreased in most countries, the prevalence in public places increased or remained unchanged in most countries between 1999 and 2018. These findings emphasise the need to strengthen smoke-free policies, especially in public places. FUNDING: Youth Team of Humanistic and Social Science of Shandong University, Jinan, China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Association of Parental Height With Offspring Stunting in 14 Low- and Middle-Income Countries.

Background: Maternal height has been confirmed to be associated with offspring stunting in low- and middle-income countries (LMICs), but only limited studies have examined the paternal-offspring association, and few studies have examined the joint effect of maternal and paternal height on stunting. Objective: To investigate the association between parental height and stunting of children aged under five in LMICs. Methods: We obtained data from the Demographic and Health Surveys (DHS) conducted in 14 LMICs from 2006 to 2016. The association between maternal and paternal height and height-for-age z score (HAZ) of children aged under five was analyzed using a linear regression model in consideration of complex survey design, and regression coefficients (ß) with 95% confidence intervals (CIs) were reported. Then, the association between maternal and paternal height quintile and child stunting was analyzed using a modified Poisson regression approach with robust error variance in consideration of complex survey design with adjustment for covariates. The effect estimates were expressed as relative risks (RRs) with 95% CIs. Results: A total of 50,372 singleton children were included and the weighted prevalence of stunting was 34.5%. Both maternal height and paternal height were associated with child HAZ (ß = 0.047; 95% CI, 0.043, 0.050; and ß = 0.022; 95% CI, 0.018, 0.025, respectively). Compared with those born to the tallest mothers and fathers, children from the shortest mothers and the shortest fathers had higher risks of stunting (adjusted RR = 1.89; 95% CI, 1.78, 2.01; adjusted RR = 1.56; 95% CI, 1.47, 1.65, respectively). The mother-offspring associations are substantively larger than the father-offspring associations for each corresponding height quintile. Children from the shortest parents had the highest risk of stunting compared with children from the tallest parents (adjusted RR = 3.23; 95% CI, 2.83, 3.68). Conclusions: Offspring born to short parents are at increased risk of stunting in LMICs, and this intergenerational effect is partly driven by maternal intrauterine influence. This suggests the importance of improving the nutritional status of children and adults in LMICs, especially female caregivers.

Prevalence and trends in tobacco use among adolescents aged 13-15 years in 143 countries, 1999-2018: findings from the Global Youth Tobacco Surveys.

BACKGROUND: Tobacco use is a leading preventable cause of morbidity and mortality worldwide. Little is known about recent prevalence and trends in tobacco use among adolescents globally. We aimed to assess the recent global prevalence of tobacco use in young adolescents and the secular trends in prevalence between 1999 and 2018. METHODS: We used the most recent Global Youth Tobacco Surveys data on adolescents aged 13-15 years from 143 countries or territories that had done at least one survey between Jan 1, 2010, and Dec 31, 2018, to assess the recent prevalence of tobacco use; and data from 140 countries that had done two or more surveys between Jan 1, 1999, and Dec 31, 2018, to assess the trends in the prevalence of tobacco use. FINDINGS: 530 234 adolescents were included from the 143 countries that had done at least one survey between 2010 and 2018. 1 192 312 adolescents were included from the 140 countries that had done two or more surveys between 1999 and 2018. The most recent global prevalence of cigarette smoking was 11·3% (95% CI 10·3-12·3) in boys and 6·1% (5·6-6·6) in girls, based on cigarette smoking on at least 1 day during the past 30 days, 6·0% (5·5-6·6) and 2·6% (2·4-2·9) based on smoking on at least 3 days, and 4·2% (3·8-4·6) and 1·6% (1·4-1·8) based on smoking on at least 6 days. The most recent prevalence of the use of tobacco products other than cigarettes (eg, chewing tobacco, snuff, dip, cigars, cigarillos, pipe, electronic cigarettes) on at least 1 day during the past 30 days was 11·2% (9·9-12·6) in boys and 7·0% (6·4-7·7) in girls. The most recent prevalence of any tobacco use on at least 1 day during the past 30 days was 17·9% (16·1-19·6) in boys and 11·5% (10·5-12·4) in girls. The prevalence of cigarette smoking on at least 1 day during the past 30 days decreased between the first and last surveys in 80 (57·1%) of 140 countries, was unchanged in 39 countries (27·9%), and increased in 21 countries (15·0%). However, the prevalence of the use of tobacco products other than cigarettes was unchanged or increased in 81 (59·1%) of 137 countries. INTERPRETATION: The global prevalence of tobacco use among adolescents aged 13-15 years was substantial. Although the prevalence of cigarette smoking decreased over time in the majority of countries, the prevalence of the use of other tobacco products increased or did not change in the majority of countries during the past two decades. These findings re-emphasise the need to strengthen tobacco control efforts among young adolescents globally. FUNDING: Shandong University.

Physical Activity and Sedentary Behavior among Young Adolescents in 68 LMICs, and Their Relationships with National Economic Development.

It is unclear whether physical activity and sedentary behavior are associated with economic development in low- and middle-income countries (LMICs). We aimed to assess the association between these two behaviors and country economic development among young adolescents in LMICs. Data came from the Global School-based Student Health Survey (GSHS) conducted between 2009 and 2016 in 68 LMICs. A total of 180,298 adolescents aged 12-15 years were included; 15.3% of young adolescents achieved the recommended level for sufficient physical activity (≥60 min/day of physical activity of any kind per week according to WHO) and 64.6% achieved a low sedentary behavior (≤2 h of sitting activities/day according to some guidelines, not accounting for sitting time at school or for doing homework). However, only 9.1% of young adolescents met the recommended levels of both behaviors. Comparing the lowest to the highest quintiles of a country's purchasing power parity per capita (PPP), mean values of both physical activity (boys: 2.55 to 2.96 days/week; girls: 2.10 to 2.31 days/week) and sedentary behavior(boys: 1.86 to 3.13 h/day; girls: 1.83 to 3.53 h/day) increased. The prevalence of having both recommended behaviors decreased among boys (12.0% to 10.0%) and girls (9.6% to 4.9%) (p < 0.001). Although there might be an ecological fallacy, the findings emphasize the need for interventions to increase physical activity and reduce sedentary behavior among children and young adolescents.

Increased risk of metabolic dysfunction in children conceived by assisted reproductive technology.

AIMS/HYPOTHESIS: Assisted reproductive technology (ART) is the most widely used treatment for infertility and has resulted in millions of births worldwide. The safety of the offspring has been of the utmost concern. Previous studies suggested an increase in metabolic disorders in offspring later in life. The aim of the present study was to investigate metabolic changes at age 6-10 years in offspring conceived as a result of in vitro fertilisation/intracytoplasmic sperm injection (IVF/ICSI). METHODS: A total of 380 children born from IVF/ICSI and a matched control group of 380 naturally conceived children, all aged 6-10 years, were recruited. Anthropometric measures, ultrasound and serum tests were performed for body mass, glucose metabolism and lipid profiles, and examination of vasculature structure. RESULTS: The children conceived by ART showed significantly higher fasting blood glucose and serum insulin levels and HOMA-IR (adjusted ß [95% CI]: fasting blood glucose 0.49 [0.42, 0.55]; loge-transformed insulin 0.28 [0.20, 0.35]; loge-transformed HOMA-IR 0.38 [0.30, 0.46]), as well as a lower HOMA-B and serum apolipoprotein A (ApoA) levels (adjusted ß [95% CI]: loge-transformed HOMA-B -0.19 [-0.27, -0.11]; ApoA -0.17 [-0.21, -0.13]), when compared with the control group. Furthermore, the ultrasound scan indicated elevated carotid intima-media thickness in children conceived by ART (ß 0.13 [95% CI 0.12, 0.13]). CONCLUSIONS/INTERPRETATION: Children conceived by IVF/ICSI have a less favourable glucose and cardiovascular metabolic profile in childhood when compared with naturally conceived children. The underlying mechanisms and potential long-term consequences need to be elucidated in future studies. Graphical abstract.

The effects of overweight and obesity on left ventricular hypertrophy among hypertensive school-aged children / 中国学校卫生

Objective@#To examine the influences of overweight and obesity on left ventricular hypertrophy (LVH) in school-aged children, and to provide the scientific reference for early screening and making interventional measures for the damage of their heart structure.@*Methods@#Based on a cross-sectional survey conducted in Jinan between 2012 and 2014, a total of 327 students aged 6-17 who had hypertension were selected. Covariance analysis and trend chi-square test were used to analyze the trend of left ventricular mass index (LVMI) and abnormal LVH rate across different categories of body mass index (BMI) after adjusted for age, gender and blood pressure (BP). Logistic regression analysis was used to evaluate the effects of overweight and obesity on LVH.@*Results@#After adjusting for age, gender and BP, covariance analysis indicated that with the increase of BMI, the levels of LVMI [(26.8±1.8, 34.7±1.5, 40.1±0.9)g/m2.7] and prevalence of LVH (80.%, 22.4%, 41.4%) showed upward trends (F/χ2=22.68, 24.28, P<0.05). Compared with normal weight school-aged children, the risk of LVH increased for overweight and obese school-aged children, and the odds ratios (95% confidence intervals) were 3.83 (1.16-12.61) and 9.18 (3.10-27.19), respectively.@*Conclusion@#Overweight and obesity significantly increase the risk of LVH in school-aged children. Effective prevention and treatment of overweight and obesity may reduce the risk of abnormal cardiac structure in school-aged children.

Alcohol use among young adolescents in low-income and middle-income countries: a population-based study.

BACKGROUND: Alcohol use remains a major public health problem worldwide because of its harmful effects on physical and mental health. Few studies have used a standardised methodology to assess alcohol use among adolescents in low-income and middle-income countries (LMICs). In the present study, we aimed to compare the prevalence of alcohol use, drunkenness episodes, and drin king-related problems among young adolescents in LMICs. METHODS: For this population-based study, we used individual data from the Global School-based Student Health Surveys (GSHS) from between 2006 and 2013 in adolescents aged 12-15 years in LMICs. Data were collected using an anonymous self-reported questionnaire. This report is based on four questions assessing alcohol use, drunkenness episodes, alcohol-related drinking problems (ever had a hangover, felt sick, got into trouble with family or friends, missed school, or got into fights, as a result of drinking alcohol), and, in those who reported drinking, how alcohol was purchased. We calculated the overall and regional estimates using a meta-analysis with random-effects. FINDINGS: GSHS data from 57 countries, corresponding to a total of 139 649 young adolescents, were included in this study. The prevalence of the variables varied largely according to country and region. The overall prevalence of having at least one drink during the past 30 days was 25·0% (95% CI 19·3-30·7), and was higher among boys (27·5%, 21·9-33·2) than girls (22·5%, 18·8-26·2), and at age 14-15 years (29·0%, 23·1-34·8) than at age 12-13 years (18·9%, 15·3-22·5). The overall prevalence of having been drunk at least once during the lifetime was 17·9% (13·6-22·1); and was higher among boys (21·3%, 16·8-25·7) than girls (14·5%, 12·1-16·9), and at age 14-15 years (21·5%, 17·0-26·0) than at age 12-13 years (12·2%, 9·5-15·0). The overall prevalence of drinking-related problems was 10·6% (8·9-12·2), and was higher among boys (12·5%, 10·4-14·5) than girls (8·9%, 7·5-10·2), and at age 14-15 years (12·3%, 10·4-14·2) than at age 12-13 years (7·8%, 6·6-9·1). Among those reporting drinking, 27·8% (24·8-30·7) accessed alcohol from their friends, 23·2% (19·5-26·9) got it from family, 19·5% (17·5-21·6) bought it in a store, 9·1% (8·0-10·2) gave someone money to buy some, 2·8% (2·3-3·3) stole it, and 14·4% (12·2-16·5) got it by some other way. INTERPRETATION: Alcohol use, lifetime drunkenness, and alcohol-related problems were frequent among young adolescents in LMICs; however, with differences by country, region, sex, and age group. These findings emphasise the need for interventions to reduce alcohol use targeting young adolescents in LMICs with high prevalence of use and alcohol-related problems. FUNDING: Shandong University.