Search

AimsTo examine the relationship between changes in electronic cigarette (e-cigarette) use and subsequent cigarette smoking cessation.MethodsUsing data from the Population Assessment of Tobacco and Health Study (wave 1-wave 4), we analysed a study cohort of 3014 current adult cigarette smokers at wave 1 who tried to quit during the past 12 months. We categorised changes in e-cigarette use from wave 1 to wave 2 as: daily initiation, non-daily initiation, increase to daily use, increase to non-daily use, stable daily use, stable non-daily use, decrease from daily use, quit non-daily use and non-use. We estimated multivariable logistic regressions on short-term (≥1 month and

AimsThis study estimated annual healthcare expenditures attributable to current e-cigarette use among US adults, including current exclusive and dual/poly e-cigarette use.MethodsAnalysing the 2015-2018 National Health Interview Survey data, we estimated the impacts of e-cigarette use on healthcare utilisation among adults aged 18+ years. Healthcare utilisation outcomes were hospital nights, emergency room (ER) visits, doctor visits and home visits. Current e-cigarette use was categorised as exclusive and dual/poly e-cigarette use. The econometric model included two equations: health status as a function of e-cigarette use and other independent variables, and healthcare utilisation as a function of health status, e-cigarette use, and other independent variables. Using an 'excess utilisation' approach, we multiplied the e-cigarette-attributable fraction derived from the model by annual health expenditures to calculate healthcare expenditures attributable to current exclusive and dual/poly e-cigarette use, the sum of which were expenditures attributable to all current e-cigarette use.ResultsCurrent exclusive and dual/poly e-cigarette use, with 0.2% and 3.5% prevalence in 2015-2018, were associated with higher odds of reporting poor health status than never tobacco users. Poor health status was associated with higher odds of using the four healthcare services and a greater number of ER and doctor visits. Annual healthcare expenditures attributable to all current e-cigarette use was $15.1 billion ($2024 per user) in 2018, including $1.3 billion attributable to exclusive e-cigarette use ($1796 per user) and $13.8 billion attributable to dual/poly e-cigarette use ($2050 per user).ConclusionAdult current e-cigarette use was associated with substantial excess healthcare utilisation and expenditures.

Nonlinear photonics has unveiled new avenues for applications in metrology, spectroscopy, and optical communications. Recently, there has been a surge of interest in integrated platforms, attributed to their fundamental benefits, including compatibility with complementary metal-oxide semiconductor (CMOS) processes, reduced power consumption, compactness, and cost-effectiveness. This paper provides a comprehensive review of the key nonlinear effects and material properties utilized in integrated platforms. It discusses the applications and significant achievements in supercontinuum generation, a key nonlinear phenomenon. Additionally, the evolution of chip-based optical frequency combs is reviewed, highlighting recent pivotal works across four main categories. The paper also examines the recent advances in on-chip switching, computing, signal processing, microwave generation, and quantum applications. Finally, it provides perspectives on the development and challenges of nonlinear photonics in integrated platforms, offering insights into future directions for this rapidly evolving field.

Introduction: On April 1, 2017, California Proposition 56 (Prop 56) was implemented, increasing the excise tax on cigarettes by $2/pack. This study compares the association of Prop 56 with smoking prevalence and smoking intensity across racial/ethnic groups, further examining distinctions across income subgroups within each racial/ethnic group.Methods: The study used pooled cross-sectional data from the 2012-2018 California Behavioral Risk Factor Surveillance System. We examined two outcomes: current smoking prevalence and smoking intensity conditional on current smoking. A two-part econometric model was used to estimate the association of Prop 56 with smoking prevalence and intensity using multiple logistic regression and multiple linear regression, respectively. The two-part model was run separately for all adults (full sample) and each racial/ethnic group. Within each racial/ethnic group, we ran stratified analyses by income subgroups.Results: The results indicated that Prop 56 was negatively associated with smoking prevalence among full-sample, Hispanic, White, and African American adults; and negatively associated with smoking intensity among full-sample and White smokers. Stratified analyses by race/ethnicity and income showed that Prop 56 was negatively associated with smoking prevalence among low-income full-sample and White adults and among middle-income smokers in the full, Hispanic, White, African American, and Asian samples. Prop 56 was negatively associated with smoking intensity among middle-income Hispanic and high-income White smokers. The association between Prop 56 and smoking intensity was positive among high-income African American smokers.Conclusion: Prop 56 was associated with a reduction in smoking prevalence across multiple racial/ethnic groups, particularly within the low- and middle-income subgroups.Policy implications: Our findings indicate that the reduction in smoking prevalence immediately following the implementation of California Proposition 56 tobacco tax increase was significant across a variety racial/ethnic groups, particularly low- and middle-income subgroups. We found differential responses in smoking prevalence across income groups among Whites but not among racial/ethnic minorities. We found no evidence of any significance association between Proposition 56 and smoking intensity among minorities and economically vulnerable populations, except for middle-income Hispanics. Researchers, policymakers, and advocates should consider additional merits of targeted, community-based, non-economic tobacco control interventions in reaching low- and middle-income groups within racial/ethnic minorities.

Background and aims: Non-Hispanic African Americans (African Americans) smoke fewer cigarettes per day (CPD) and are more likely to be non-daily smokers than non-Hispanic whites (whites). Little is known about how changes in cigarette prices might contribute to these differences. This study aimed to measure the price-responsiveness of smoking participation, non-daily smoking among current smokers and smoking intensity among daily or non-daily smokers for African Americans and compare the price-responsiveness estimates with those for whites.Design: Analysis of data from the 2009-14 National Adult Tobacco Surveys and cigarette price data from the Tax Burden on Tobacco report.Setting: United States.Participants: A total of 19 232 African American and 197 939 white adults aged 18+.Measurements: We used a three-part econometric model of cigarette demand to estimate the price-responsiveness of smoking participation, daily versus non-daily smoking and smoking intensity. The model controlled for secular variation, state-level anti-smoking sentiment and smoke-free air laws and socio-demographics.Findings: In 2009-14, 20.2% of African Americans and 17.7% of whites identified as current smokers; 70.2% of African American smokers and 81.4% of white smokers smoked daily. The price elasticity of smoking participation was significant for whites at -0.16 [95% confidence interval (CI) = -0.23, -0.09], indicating that a 10% increase in prices would reduce smoking participation by 1.6%, but not statistically significant for African Americans, and this racial/ethnic differential price responsiveness was not statistically significant. The price elasticity of smoking intensity was statistically significant for African American daily smokers at -0.29 (95% CI = -0.42, -0.16), but not statistically significant for white daily smokers, and this racial/ethnic differential price-responsiveness was statistically significant. The price elasticity of daily versus non-daily smoking among current smokers, and the price elasticity of smoking intensity among non-daily smokers were not statistically significant for either racial/ethnic group.Conclusion: In the United States, cigarette price increases may have stronger effects on decreasing daily smokers' consumption among African Americans than among non-Hispanic whites.

IntroductionTo study the association between health care utilization and menthol cigarette use and whether the association differed between African American (AA) and non-AA smokers.MethodsWe analyzed the three most recent 2005, 2010, and 2015 National Health Interview Survey Cancer Control Supplements. After incorporating propensity score weights adjusting for observed differences between menthol and non-menthol users, we estimated Zero-Inflated Poisson models on hospital nights, emergency department visits, doctor visits, and home visits as a function of menthol use status and other covariates separately for current cigarette smokers and recent quitters (former smokers quitting cigarette smoking ≤ 4 years).ResultsAlthough current menthol smokers smoked fewer cigarettes per day than current non-menthol smokers, they did not differ from current non-menthol smokers in health care utilization. Among recent quitters, those who used to smoke menthol cigarettes had higher odds of having hospital nights than those who used to smoke non-menthol cigarettes. However, we did not find any significant association between menthol use and other health care utilization-emergency department visits, doctor visits, and home visits-among recent quitters. Moreover, compared with non-AA recent quitters, AA recent quitters had higher odds of having home visits, but fewer home visits, if they used to smoke menthol cigarettes.ConclusionMenthol use was associated with greater hospitalization among recent quitters, and the association between home visits and menthol use differed between AA and non-AA recent quitters.ImplicationsThis is the first study that used econometric models to study the association between health care utilization and menthol cigarette use and examine whether the association differed between AA and non-AA smokers. Our study found health care utilization did not differ by menthol use status for current smokers, although current menthol smokers smoked fewer cigarettes per day than current non-menthol smokers. However, we found menthol use was associated with higher odds of having hospital nights for recent quitters. We also found AA recent quitters had a different association between home visits and menthol use compared with non-AA recent quitters.

Objectives. To compare the association of California Proposition 56 (Prop 56), which increased the cigarette tax by $2 per pack beginning on April 1, 2017, with smoking behavior among low- and high-income adults.Methods. Drawing on a sample of 17 206 low-income and 21 324 high-income adults aged 21 years or older from the 2012 to 2018 California Behavioral Risk Factor Surveillance System data, we explored 2 outcomes: current smoking prevalence and smoking intensity (average number of cigarettes per day among current smokers). For each income group, we estimated a multivariable logistic regression to analyze the association of Prop 56 with smoking prevalence and a multivariable linear regression to analyze the association of Prop 56 with smoking intensity.Results. Although we observed no association between smoking intensity and Prop 56, we found a statistically significant decline in smoking prevalence among low-income adults following Prop 56. No such association was found among the high-income group.Conclusions. Given that low-income Californians smoke cigarettes at greater rates than those with higher incomes, our results provide evidence that Prop 56 is likely to reduce income disparities in cigarette smoking in California.

IntroductionThis study examined the effects of cigarette price on intention to quit, quit attempts, and successful cessation among African American smokers in the United States and explored whether price effects differed by income level and menthol use status. Price effects were further compared to White counterparts.MethodsWe used pooled cross-sectional data from 2006 to 2007 and 2010 to 2011 Tobacco Use Supplements to the Current Population Survey to analyze 4213 African American recent active smokers. Three dependent variables were examined: any quit attempts in the past 12 months, successful cessation for at least 3 months, and intention to quit in the next 6 months. For each dependent variable, separate multiple logistic regression models were estimated to determine the impact of cigarette prices.ResultsThere was no indication that price was associated with quit attempts or successful cessation, but price was positively associated with increased odds of intending to quit among African American smokers (p < .001). In contrast, prices were positively associated with intention to quit and quit attempts for White smokers. The association between price and intention to quit was significantly positive for African American low-income and menthol smokers but was not statistically significant for African American high-income and non-menthol smokers. There was no evidence of a price effect on quit attempts and successful cessation for each subgroup of African Americans.ConclusionsTobacco tax policy alone may not be enough to increase quit attempts or successful cessation among African Americans. Community-based cessation programs tailored toward African American smokers, especially low-income menthol smokers, are needed.ImplicationsThe results revealed that, among African American smokers, particularly among low-income and menthol smoking African American smokers, price appears to be positively associated with intention to quit; nevertheless, this deterrent effect does not appear to translate to actualized quit attempts or successful cessation. Increasing cigarette prices as a standalone policy may not be independently effective in increasing quit attempts and successful cessation within the African American community. Community-based cessation interventions tailored for African Americans are needed to help further translate desired cessation into actualized quit attempts.

IntroductionThe purpose of this study is to estimate healthcare utilization and healthcare costs due to secondhand smoke exposure at home for children in the U.S.MethodsUsing data from the 2000, 2005, and 2010 U.S. National Health Interview Surveys, the authors analyzed the association between secondhand smoke exposure at home and utilization of three types of healthcare services (hospital nights, emergency room visits, and doctor visits) for children aged 3-14 years (N=16,860). A zero-inflated Poisson regression model was used to control for sociodemographic characteristics and the number of months without health insurance. The authors determined excess healthcare utilization attributable to secondhand smoke exposure at home for children and then estimated annual secondhand smoke-attributable healthcare costs as the product of annual excess healthcare utilization and unit costs obtained from the 2014 Medical Expenditures Panel Survey. This study was conducted from 2016 to 2018.ResultsThe prevalence of secondhand smoke exposure at home for children in 2000, 2005, and 2010 was 25.0%, 12.3%, and 9.1%, respectively. Secondhand smoke exposure at home was positively associated with emergency room visits, but was not significantly associated with nights at the hospital or doctor visits for children. Secondhand smoke exposure at home for children resulted in an excess of 347,156 emergency room visits in 2000, 124,412 visits in 2005, and 101,570 visits in 2010, which amounted to $215.1 million, $77.1 million, and $62.9 million in excess annual healthcare costs (2014 dollars) in 2000, 2005, and 2010, respectively.ConclusionsAlthough U.S. healthcare costs attributable to secondhand smoke exposure at home for children are declining, interventions to reduce secondhand smoke exposure at home for children are still needed to reduce the economic burden attributable to secondhand smoke exposure.

ObjectivesWe review the Population Health Impact Model (PHIM) developed by Philip Morris International and used in its application to the US Food and Drug Administration (FDA) to market its heated tobacco product (HTP), IQOS, as a modified-risk tobacco product (MRTP). We assess the model against FDA guidelines for MRTP applications and consider more general criteria for evaluating reduced-risk tobacco products.MethodsIn assessing the PHIM against FDA guidelines, we consider two key components of the model: the assumptions implicit in the model (outcomes included, relative harm of the new product vs cigarettes, tobacco-related diseases considered, whether dual or polyuse of the new product is modelled, and what other tobacco products are included) and data used to estimate and validate model parameters (transition rates between non-smoking, cigarette-only smoking, dual use of cigarettes and MRTP, and MRTP-only use; and starting tobacco use prevalence).ResultsThe PHIM is a dynamic state transition model which models the impact of cigarette and MRTP use on mortality from four tobacco-attributable diseases. The PHIM excludes morbidity, underestimates mortality, excludes tobacco products other than cigarettes, does not include FDA-recommended impacts on non-users and underestimates the impact on other population groups.ConclusionThe PHIM underestimates the health impact of HTP products and cannot be used to justify an MRTP claim. An assessment of the impact of a potential MRTP on population health should include a comprehensive measure of health impacts, consideration of all groups impacted, and documented and justifiable assumptions regarding model parameters.

IntroductionThis study estimated the health care utilization and expenditures attributable to the use of smokeless tobacco (ST) which includes chewing tobacco, snuff, dip, snus, and dissolvable tobacco among US adults aged 18 and older.MethodsWe used data from the 2012-2015 National Health Interview Surveys (n = 139451 adults) to estimate a zero-inflated Poisson (ZIP) regression model on four health care utilization measures among US adults (hospital nights, emergency room [ER] visits, doctor visits, and home care visits) specified as a function of tobacco use status, and other covariates. Tobacco use status was classified into four categories: current ST users, former ST users, non-ST tobacco users, and never tobacco users. ST-attributable utilization was calculated based on the estimated ZIP model using an "excess utilization" approach. It was then multiplied by the unit cost estimated from the 2014 Medical Expenditures Panel Survey data to derive ST-attributable health care expenditures.ResultsDuring 2012-2015, 2.1% of adults were current ST users and 7.7% were former ST users. ST-attributable health care utilization amounted to 681000 hospital nights, 624000 ER visits, and 4.6 million doctor visits per year (home care visits results were not significant). This resulted in annual excess expenditures of $1.8 billion for hospitalizations, $0.7 billion for ER visits, and $0.9 billion for doctor visits, totaling over $3.4 billion (in 2014 dollars).ConclusionComprehensive tobacco control policies and interventions are needed to reduce ST use and the associated health care burden.ImplicationsThis is the first study to assess the impact of ST use on health care burden in the United States. Findings indicate that excess annual health care expenditures attributable to ST use for US adults were $3.4 billion in 2014 dollars.

IntroductionThe tobacco product landscape has changed substantially. Little is known about the recent pattern of polytobacco use (at least two tobacco products) among US adults and its relationship to nicotine dependence.MethodsUsing the 2012-2013 and 2013-2014 National Adult Tobacco Survey (NATS) data (N = 135 425 adults), we analyzed the prevalence and correlates of polytobacco use among each of the six categories of current tobacco user (cigarettes, cigars, pipes, hookah, e-cigarettes, and smokeless tobacco). Based on five nicotine dependence symptom measures from the NATS, difference in the prevalence of dependence symptoms between polytobacco and sole-product users for each category of tobacco user was assessed using multivariable regression analyses.ResultsDuring 2012-2014, 25.1% of adults were current users of any tobacco product. Among them, 32.5% were poly users with the largest poly use category being dual use of cigarettes and e-cigarettes (30.2%). Poly use prevalence was the lowest among current cigarette smokers (38.7%), followed by current users of smokeless tobacco (52.4%), hookah (59.2%), cigars (69.3%), e-cigarettes (80.9%), and pipes (86.2%). Among each category of current tobacco user, the prevalence of dependence symptom was consistently greater in polytobacco users than sole users for every symptom measure. After controlling for frequency of use and demographic covariates, the difference in nicotine dependence between poly users and sole users was statistically significant and consistent across all symptom measures for each category of tobacco user.ConclusionsBetween 52% and 86% of noncigarette tobacco users and nearly 40% of cigarette smokers engaged in polytobacco use. Poly users showed greater nicotine dependence than sole-product tobacco users.ImplicationsThis study examines recent patterns of polytobacco use separately for US adult current cigarette smokers, cigar smokers, pipe smokers, hookah users, e-cigarette users, and smokeless tobacco users. By including more tobacco products, particularly e-cigarettes and hookah, this study provides more comprehensive insight into polytobacco use. This study is also unique in comparing nicotine dependence between polytobacco and sole-product users among each category of tobacco users. Our results indicate that polytobacco use is very common and is associated with greater likelihood of reporting nicotine dependence symptoms. Tobacco cessation policies and programs should be tailored to address polytobacco use.

IntroductionThe proportion of smokers who do not smoke daily has increased over time, but nondaily smokers are a heterogeneous group. We compare characteristics and other tobacco product use of infrequent nondaily, frequent nondaily, and daily US adult smokers.MethodsWe analyzed data from the 1998, 2000, 2005, and 2010 National Health Interview Surveys. Current smokers were categorized as daily, infrequent nondaily (smoked 1-12 days in the past 30 days), and frequent nondaily (smoked 13-29 days in the past 30 days) smokers. Multinomial logistic regression analysis was used to analyze the correlates of infrequent nondaily, frequent nondaily, and daily smoking.ResultsAmong current smokers, 8.3% were infrequent nondaily, 8.1% were frequent nondaily, and 83.6% were daily smokers. The prevalence of infrequent versus daily smoking increased over time, with a smaller increase among non-Hispanic Blacks than non-Hispanic Whites. The adjusted odds of both infrequent and frequent smoking versus daily smoking differed by age, race/ethnicity, education, poverty status, marital status, region, quit attempts in the past 12 months, and binge drinking. Snuff users (vs. non-snuff users) were 2.4 times as likely to be infrequent than daily smokers. There were also differences in race/ethnicity, education, marital status, region, quit attempts, and snuff use between infrequent versus frequent smokers.ConclusionInfrequent smokers differ from both frequent and daily smokers in socio-demographics, quit attempts, and snuff use. The heterogeneity of nondaily smokers should be considered in developing targeted tobacco control and smoking cessation programs.ImplicationsInfrequent and frequent nondaily smokers were found to differ from daily smokers in age, race/ethnicity, education, poverty status, marital status, region, and quit attempts and they were different from each other in race/ethnicity, education, marital status, region, and quit attempts. Binge drinkers were more likely to be infrequent smokers and frequent smokers versus daily smokers. Current snuff users were found to have increased odds of infrequent smoking versus daily smoking and versus frequent smoking. These results highlight the importance of acknowledging the differences among nondaily smokers in smoking frequency in developing targeted tobacco control and smoking cessation programs.

ObjectivesCigar use in the United States is a growing public health concern because of its increasing popularity. We estimated health care utilization and expenditures attributable to cigar smoking among US adults aged ≥35.MethodsWe analyzed data on 84 178 adults using the 2000, 2005, 2010, and 2015 National Health Interview Surveys. We estimated zero-inflated Poisson (ZIP) regression models on hospital nights, emergency department (ED) visits, physician visits, and home-care visits as a function of tobacco use status-current sole cigar smokers (ie, smoke cigars only), current poly cigar smokers (smoke cigars and smoke cigarettes or use smokeless tobacco), former sole cigar smokers (used to smoke cigars only), former poly cigar smokers (used to smoke cigars and smoke cigarettes or use smokeless tobacco), other tobacco users (ever smoked cigarettes and used smokeless tobacco but not cigars), and never tobacco users (never smoked cigars, smoked cigarettes, or used smokeless tobacco)-and other covariates. We calculated health care utilization attributable to current and former sole cigar smoking based on the estimated ZIP models, and then we calculated total health care expenditures attributable to cigar smoking.ResultsCurrent and former sole cigar smoking was associated with excess annual utilization of 72 137 hospital nights, 32 748 ED visits, and 420 118 home-care visits. Annual health care expenditures attributable to sole cigar smoking were $284 million ($625 per sole cigar smoker), and total annual health care expenditures attributable to sole and poly cigar smoking were $1.75 billion.ConclusionsComprehensive tobacco control policies and interventions are needed to reduce cigar smoking and the associated health care burden.

ObjectiveTo evaluate the impact of cigarette prices on adult smoking for four US racial/ethnic groups: whites, African-Americans, Asians and Hispanics.MethodsWe analysed pooled cross-sectional data from the 2006/2007 and 2010/2011 Tobacco Use Supplement to the Current Population Survey (n=339 921 adults aged 18+) and cigarette price data from the Tax Burden on Tobacco. Using a two-part econometric model of cigarette demand that controlled for sociodemographic characteristics, state-level antismoking sentiment, local-level smoke-free air laws and monthly indicator, we estimated for each racial/ethnic group the price elasticities of smoking participation, smoking intensity and total demand for cigarettes.ResultsSmoking prevalence for whites, African-Americans, Asians and Hispanics during the study period was 18.3%, 16.1%, 8.2% and 11.3%, respectively. The price elasticity of smoking participation was statistically significant for whites, African-Americans, Asians and Hispanics at -0.26, -0.10, -0.42 and -0.11, respectively. The price elasticity of smoking intensity was statistically significant among whites (-0.22) and African-Americans (-0.17). Overall, the total price elasticity of cigarette demand was statistically significant for all racial/ethnic groups: 0.48 for whites, -0.27 for African-Americans, -0.22 for Asians and -0.15 for Hispanics.ConclusionsOur results suggest that raising cigarette prices, such as via tobacco tax increases, would result in reduced cigarette consumption for all racial/ethnic groups. The magnitude of the effect and the impact on cessation and reduced smoking intensity differ across these groups.

ObjectiveTo estimate healthcare costs attributable to secondhand smoke (SHS) exposure at home among nonsmoking adults (18+) in the U.S.MethodsWe analyzed data on nonsmoking adults (N=67,735) from the 2000, 2005, and 2010 (the latest available data on SHS exposure at home) U.S. National Health Interview Surveys. This study was conducted from 2015 to 2017. We examined hospital nights, home care visits, doctor visits, and emergency room (ER) visits. For each, we analyzed the association of SHS exposure at home with healthcare utilization with a Zero-Inflated Poisson regression model controlling for socio-demographic and other risk characteristics. Excess healthcare utilization attributable to SHS exposure at home was determined and multiplied by unit costs derived from the 2014 Medical Expenditures Panel Survey to determine annual SHS-attributable healthcare costs.ResultsSHS exposure at home was positively associated with hospital nights and ER visits, but was not statistically associated with home care visits and doctor visits. Exposed adults had 1.28 times more hospital nights and 1.16 times more ER visits than non-exposed adults. Annual SHS-attributable healthcare costs totaled $4.6 billion (including $3.8 billion for hospital nights and $0.8 billion for ER visits, 2014 dollars) in 2000, $2.1 billion (including $1.8 billion for hospital nights and $0.3 billion for ER visits) in 2005, and $1.9 billion (including $1.6 billion for hospital nights and $0.4 billion for ER visits) in 2010.ConclusionsSHS-attributable costs remain high, but have fallen over time. Tobacco control efforts are needed to further reduce SHS exposure at home and associated healthcare costs.

AimsTo examine the transitions in smoking status among non-daily smokers who transitioned to daily or former smokers or remained as non-daily smokers during a 12-month period. We analyzed factors associated with these transitions, including the use of cigars and smokeless tobacco (SLT).DesignSecondary data analyses using pooled data from the 2003, 2006/07 and 2010/11 Tobacco Use Supplements to the Current Population Survey (TUS-CPS).SettingUnited States.ParticipantsSelf-respondents aged 18+ who have smoked for more than 5 years and were non-daily smokers 12 months before the interview (n = 13 673, or 14.5% of current smokers).MeasurementsMultinomial logistic regression model to determine the correlates of non-daily to daily, stable non-daily and non-daily to former smoking transitions among non-daily smokers at baseline. The model controlled for socio-demographic factors and the use of cigars and SLT.FindingsOf the adults in our sample, 2.6% were non-daily smokers at baseline. Among these, 69.7% remained non-daily smokers (stable non-daily smokers), 18.4% became daily smokers (non-daily to daily smokers) and 11.9% quit smoking (non-daily to former smokers) after 12 months. The non-daily to daily versus stable non-daily smoking transition was less likely among those who were aged 65+ (P = 0.018), male (P

IntroductionTobacco use prevalence has been commonly estimated on a product by product basis and the extent of polytobacco use among current users of each tobacco product is not well understood. This study aimed to examine the prevalence, trends, and correlates of polytobacco use among current users of cigarettes, cigars, chewing tobacco, and snuff in US adults aged ≥18.MethodsWe used pooled data from the 1998, 2000, 2005, and 2010 Cancer Control Supplements of the National Health Interview Survey (N = 123 399 adults). Multivariate logistic regression models were estimated to determine significant factors associated with polytobacco use.ResultsIn 2010, the prevalence of polytobacco use was 8.6% among current cigarette smokers, 50.3% among current cigar users, 54.8% among current chewing tobacco users, and 42.5% among current snuff users. After controlling for other covariates, gender and race/ethnicity did not show consistent associations with poly-use across these four groups of current tobacco users; however, a positive association of young adulthood, less than high school education, and binge drinking with poly-use was consistently found among all these groups.ConclusionsPolytobacco use is extremely popular among current users of non-cigarette tobacco products. Polytobacco use patterns differ across sociodemographic subpopulations, and the gender and racial/ethnic profiles in poly-users vary across different groups of current tobacco users. Tobacco control strategies need to consider the interrelationships in the use of different tobacco products and the diverse profiles of poly-users in order to develop tailored tobacco prevention and intervention policies to further reduce the burden of tobacco use.

ObjectiveWe examined the levels and change in prevalence of self-reported secondhand smoke (SHS) exposure at home, and analyzed sociodemographic differences in exposure among children (aged 0-17 years) and nonsmoking adults (aged ≥18 years) in the United States in 2000 and 2010.MethodsWe included 18,731 children and 44,049 adults from the 2000 and 2010 National Health Interview Survey Cancer Control Supplements. We used multivariate logistic regression to determine the factors associated with exposure.ResultsThe prevalence of self-reported SHS exposure declined from 2,627 of 10,636 (24.7%) to 663 of 8,095 (8.2%) for children and from 2,863 of 23,665 (12.1%) to 897 of 20,384 (4.4%) for adults from 2000 to 2010. SHS exposure declined for all population subgroups between the two years, but differences were found. Compared with 2000, children aged 12-17 years in 2010 were no longer more likely than children aged 0-5 years to be exposed to SHS. Non-Hispanic black children and adults were more likely than non-Hispanic white children and adults to be exposed to SHS in 2010. In 2010, no differences were found for children whose parents had a higher level of education, and no differences were observed for children or adults with high family income vs. other levels of family income. Children living in the Midwest and South had higher levels of SHS exposure than children in other regions in 2010.ConclusionsSelf-reported SHS exposure at home declined for all population subgroups from 2000 to 2010, but socioeconomic differences existed for some subgroups in both years. Current tobacco control policies need to be improved to reach all population subgroups so that SHS exposure can be further reduced, especially among vulnerable populations.

In agricultural production, it is crucial to increase the availability of phosphorus (P) in cultivated soil to solve the P limitation. Arbuscular mycorrhizal fungi (AMF) have been proven to promote crop nutrient absorption effectively, while biochar can lead to improvements in soil properties. However, the possible synergistic effect of AMF and biochar on P uptake by crops as well as its underlying mechanisms are unclear. In this study, we conducted a pot experiment to explore the effects of biochar and AMF (Glomus etunicatum) on the community of rhizospheric phosphate-solubilizing microorganisms (PSMs) of maize (Zea mays L. Xianyu-335) using metagenomic methods. The experiment used 0 mg P2O5 g·kg−1 soil (P0) and 30 mg P2O5 g·kg−1 soil (P30) application rates. Each P application rate included 0 (NC), 20 g·kg−1 biochar (BC) addition, inoculation AMF, and without AMF treatments (NM) for a total of eight treatments. During the experiment, both the P uptake and the biomass of maize were measured. The study found that the combination of AMF and biochar significantly increased the mycorrhizal colonization rate of maize roots, regardless of P application level. It was observed that the P uptake by maize was significantly increased when exposed to a combination of AMF and biochar. The increase in P uptake in P0 treatments was 67% higher than the sum of the effects of biochar and AMF inoculation alone. The increase was only 35% higher in P30 treatments, demonstrating a substantially higher interactive effect under P0 than under P30 conditions. The AM-BC treatments significantly increased the abundance of Streptomyces, Bacillus, and Pseudomonas, genera that are known to contain PSMs. In addition, the abundance of genes related to P-cycling (gcd, phoD, and ugpQ) in PSMs increased significantly by 1.5–1.8 times in AM-BC treatments compared with NM-BC and AM-NC treatments under P0 conditions. This increase was significantly and positively correlated with the P uptake. Overall, the results suggest that biochar can help AMF colonize the roots, increasing the functional roles of PSMs in the rhizosphere, which in turn promotes P uptake and biomass in maize. This study provides a new way to improve P-use efficiency and reduce the need for P-fertilizer application in agricultural production. [ABSTRACT FROM AUTHOR]