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A L Frazier - One of the best experts on this subject based on the ideXlab platform.
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weight concerns weight control behaviors and Smoking Initiation
Pediatrics, 1999Co-Authors: Catherine Tomeo, Alison E Field, Catherine S Berkey, Graham A Colditz, A L FrazierAbstract:Objective. To examine the cross-sectional relationships between weight concerns, weight control behaviors, and Initiation of tobacco use among youths. Study Design. Smoking status, weight concerns, and weight control behaviors were assessed in a cross-sectional sample of 16 862 children, 9 to 14 years of age, in 1996. Logistic regression was used to examine the relationship between weight concerns, weight control behaviors, and early stages of Smoking Initiation (precontemplation, contemplation, and experimentation). All analyses were adjusted for age, body mass index, and known predictors of Initiation. Results. Approximately 9% of participants had experimented with cigarettes, and 6% were contemplating cigarette Smoking. Contemplation of tobacco use was associated with misperception of being overweight (boys: odds ratio [OR], 1.65; 95% confidence interval [CI], 1.10–2.48), unhappiness with appearance (girls: OR, 2.05; 95% CI, 1.48–2.84; boys: OR, 1.60; 95% CI, 1.05–2.42), and a tendency to change eating patterns around peers (girls: OR, 2.87; 95% CI, 2.28–3.62; boys: OR, 1.83; 95% CI, 1.25–2.66). Experimentation with cigarettes was associated with daily exercise to control weight among boys (OR, 1.92; 95% CI, 1.07–3.43) and with monthly purging (OR, 2.54; 95% CI, 1.27–5.07) and daily dieting among girls (OR, 1.79; 95% CI, 1.09–2.96). Conclusions. Our findings suggest that, among both girls and boys, contemplation of Smoking is positively related to weight concerns. Experimentation seems to be positively related to weight control behaviors. It is important for both pediatricians and comprehensive school health programs to address healthy methods of weight maintenance and to dispel the notion of tobacco use as a method of weight control.
Kenneth S. Kendler - One of the best experts on this subject based on the ideXlab platform.
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toward a comprehensive developmental model of Smoking Initiation and nicotine dependence
Drug and Alcohol Dependence, 2014Co-Authors: Olaya Garciarodriguez, Carlos Blanco, Melanie M Wall, Shuai Wang, Chelsea J Jin, Kenneth S. KendlerAbstract:Abstract Background This study aims to identify predictors of Smoking Initiation and nicotine dependence (ND) to develop a comprehensive risk-factor model based on Kendler's development model for major depression. Methods Data were drawn from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), Wave 2 ( n = 34,653). Risk factors were divided into five developmental tiers according to Kendler's model (childhood, early adolescence, late adolescence, adulthood, past-year). Hierarchical logistic regression models were built to predict the risk of Smoking Initiation and the risk of ND, given Initiation. The continuation ratio (CR) was tested by ordinal logistic regression to examine whether the impact of the predictors was the same on Smoking Initiation or ND. Results The final models highlighted the importance of different tiers for each outcome. The CR identified substantial differences in the predictors of Smoking Initiation versus ND. Childhood tier appears to be more determinant for Smoking Initiation while the effect of more distal tiers (i.e. childhood and early adolescence) was tempered by more proximal ones (i.e. late adolescence, adulthood and past-year) in ND, with few sex differences. Conclusions The differential effect of some predictors on each outcome shows the complexity of pathways from Smoking Initiation to ND. While some risk factors may be shared, others impact only at one stage or have even an inverse effect. An adaptation of Kendler's developmental model for major depression showed high predictive power for Smoking Initiation and ND.
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Genetic and Cultural Transmission of Smoking Initiation: An Extended Twin Kinship Model
Behavior Genetics, 2006Co-Authors: Hermine H Maes, Kenneth S. Kendler, Michael C. Neale, Nicholas G. Martin, Andrew C. Heath, Lindon J EavesAbstract:Background Considerable evidence from twin and adoption studies indicates that genetic and shared environmental factors play a significant role in the Initiation of Smoking behavior. Although twin and adoption designs are powerful to detect genetic and environmental influences, they do not provide information on the processes of assortative mating and parent–offspring transmission and their contribution to the variability explained by genetic and/or environmental factors. Methods We examined the role of genetic and environmental factors for Smoking Initiation using an extended kinship design. This design allows the simultaneous testing of additive and non-additive genetic, shared and individual-specific environmental factors, as well as sex differences in the expression of genes and environment in the presence of assortative mating and combined genetic and cultural transmission. A dichotomous lifetime Smoking measure was obtained from twins and relatives in the Virginia 30,000 sample. Results Results demonstrate that both genetic and environmental factors play a significant role in the liability to Smoking Initiation. Major influences on individual differences appeared to be additive genetic and unique environmental effects, with smaller contributions from assortative mating, shared sibling environment, twin environment, cultural transmission and resulting genotype–environment covariance. The finding of negative cultural transmission without dominance led us to investigate more closely two possible mechanisms for the lower parent–offspring correlations compared to the sibling and DZ twin correlations in subsets of the data: (i) age × gene interaction, and (ii) social homogamy. Neither mechanism provided a significantly better explanation of the data, although age regression was significant. Conclusions This study showed significant heritability, partly due to assortment, and significant effects of primarily non-parental shared environment on Smoking Initiation.
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Association of the phosphatase and tensin homolog gene (PTEN) with Smoking Initiation and nicotine dependence
American Journal of Medical Genetics, 2006Co-Authors: Lan Zhang, Kenneth S. Kendler, Xiangning ChenAbstract:Since PTEN (phosphatase and tensin homolog) has elevated expression in rat brain (amygdala) after chronic administration of nicotine and the PTEN gene is located in the vicinity of the chromosome 10q23 linkage peak in a genome-scan study of nicotine dependence, PTEN seems a plausible candidate gene for Smoking behavior. To test this hypothesis, we use a three-group case-control design and genotype five SNPs in the PTEN gene. We compare allele and genotype frequencies between the smokers and nonsmokers and between the low nicotine dependent and high nicotine dependent subjects. Three SNPs in the PTEN gene are significantly associated with Smoking Initiation (rs1234221, P = 0.0311; rs1234213, P = 0.0002; and rs2735343, P = 0.0028). Rs1234213 also shows association with nicotine dependence (P = 0.0278). Haplotype analyses indicate that a major haplotype, 1-1-2-2-1 for rs1234221-rs2299939-rs1234213-rs2735343-rs70184, is associated with Smoking Initiation. A minor haplotype (about 3%), 1-2-2-2-1 for the same five SNPs, is observed only in the high nicotine dependence group. These results suggest that the PTEN gene may be involved in the etiology of both Smoking Initiation and nicotine dependence. © 2005 Wiley-Liss, Inc.
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Haplotypes of four novel single nucleotide polymorphisms in the nicotinic acetylcholine receptor β2‐subunit (CHRNB2) gene show no association with Smoking Initiation or nicotine dependence
American Journal of Medical Genetics, 2000Co-Authors: M A Silverman, P F Sullivan, C Harris-kerr, Brandon Wormley, M C Neale, Hannah Sadek, Kenneth S. Kendler, R E StraubAbstract:Several types of evidence, including experiments with mice that lack the nicotinic acetylcholine receptor beta2-subunit gene (CHRNB2), have suggested that a beta2-containing nicotinic receptor is necessary for at least some of the reinforcing properties of nicotine. However, sequence variations in CHRNB2 have not been reported, and its role in influencing human Smoking behavior and nicotine dependence is not known. We screened most of the introns and exons and found five novel single nucleotide polymorphisms (SNPs). We tested four of these SNPs in three large, carefully selected samples: nonsmokers (n = 317) and regular smokers low levels of nicotine dependence (ND, n = 238), or smokers with high-ND (n = 317). None of the four polymorphisms we tested, nor their estimated haplotypes, were associated with Smoking Initiation or progression to nicotine dependence.
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a population based twin study in women of Smoking Initiation and nicotine dependence
Psychological Medicine, 1999Co-Authors: Kenneth S. Kendler, M C Neale, Patrick F Sullivan, L A Corey, Charles O Gardner, Carol A PrescottAbstract:Background. The development of drug dependence requires prior Initiation. What is the relationship between the risk factors for Initiation and dependence? Methods. Using Smoking as a model addiction, we assessed Smoking Initiation (SI) and nicotine dependence (ND) by personal interview in 1898 female twins from the population-based Virginia Twin Registry. We developed a twin structural equation model that estimates the correlation between the liability to SI and the liability to ND, given SI. Results. The liabilities to SI and ND were substantially correlated but not identical. Heritable factors played an important aetiological role in SI and in ND. While the majority of genetic risk factors for ND were shared with SI, a distinct set of familial factors, which were probably partly genetic, solely influenced the risk for ND. SI was associated with low levels of education and religiosity, high levels of neuroticism and extroversion and a history of a wide range of psychiatric disorders. ND was associated with low levels of education, extroversion, mastery, and self-esteem, high levels of neuroticism and dependency and a history of mood and alcohol use disorders. Conclusions. The aetiological factors that influence SI and ND, while overlapping, are not perfectly correlated. One set of genetic factors plays a significant aetiological role in both SI and ND, while another set of familial factors, probably in part genetic, solely influences ND. Some risk factors for SI and ND impact similarly on both stages, some act at only one stage and others impact differently and even in opposite directions at the two stages. The pathway to substance dependence is complex and involves multiple genetic and environmental risk factors.
Jurgen Rehm - One of the best experts on this subject based on the ideXlab platform.
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the impact of tobacco tax cuts on Smoking Initiation among canadian young adults
American Journal of Preventive Medicine, 2006Co-Authors: Bo Zhang, Joanna E Cohen, Roberta Ferrence, Jurgen RehmAbstract:Background Although the majority of smokers initiate Smoking during their teenage years, significant rates of Initiation occur among young adults. Adolescents are more price sensitive than adults, but little is known about the impact of tobacco taxation on Smoking Initiation among young adults. Using a longitudinal design, this study examined the impact of decreased cigarette price, resulting from tobacco tax cuts, on Smoking Initiation among Canadian young adults aged 20 to 24 years. Methods Using Statistics Canada's National Population Health Survey longitudinal file, this study examined young adults who did not smoke at baseline in 1994–1995 ( n =636, representing over 1 million young adults) and who were reassessed at follow-up (1996–1997). Multivariable logistic regression analysis using bootstrap weights was conducted to estimate the impact of decreased cigarette price on Smoking Initiation. The analysis controlled for the potential confounding effect of sociodemographic and tobacco control variables. Sensitivity analyses were conducted. Price elasticity was estimated. Analyses were conducted in 2003 and 2004. Results Approximately 10% of young adults had initiated Smoking at follow-up. Decreased cigarette price was significantly associated with higher Smoking Initiation (adjusted odds ratio per $1 decrease for a carton of cigarettes=1.15, 95% confidence interval [CI]=1.01–1.32, p =0.042). Sensitivity analyses showed similar results. Price elasticity was 3.36 (95% CI=0.07–6.75). Conclusions Young adults are sensitive to cigarette prices. Reductions in cigarette prices will lead to increased Smoking Initiation among this group. Tobacco taxation should be an effective strategy to reduce Smoking Initiation among young adults.
T H Lam - One of the best experts on this subject based on the ideXlab platform.
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parental Smoking exposure to secondhand smoke at home and Smoking Initiation among young children
Nicotine & Tobacco Research, 2011Co-Authors: M P Wang, T H LamAbstract:Introduction: To investigate the associations of parental Smoking and secondhand smoke (SHS) exposure at home with Smoking Initiation among young children in Hong Kong. Methods: A prospective school-based survey of Hong Kong primary 2–4 students was conducted at baseline in 2006 and followed up in 2008. Self-administered anonymous questionnaires were used to collect information about Smoking, SHS exposure at home, parental Smoking, and sociodemographic characteristics. Cross-sectional and prospective associations of SHS exposure at home and parental Smoking with student Smoking were analyzed using logistic regression adjusting for potential confounders. Results: Cross-sectional association between parental Smoking and ever Smoking was significant with adjustment of sociode mographic characteristics but became insignificant after adjust ing for home SHS exposure. Home SHS exposure mediated the association between parental Smoking and students Smoking (p = .03). Prospectively, parental Smoking was not associated with Smoking Initiation after adjusting for home SHS exposure. Each day increase in home SHS exposure significantly predicted 16% excess risk of Smoking Initiation after adjusting for parental Smoking. The prospective effect of parental Smoking on Smoking Initiation was significantly mediated by baseline home SHS exposure (p < .01). Conclusions: Higher exposure to SHS at home predicted Smoking Initiation of young Chinese children in Hong Kong independent of parental Smoking status. On the other hand, the effect of parental Smoking on Smoking Initiation was mediated through SHS exposure at home. To prevent children from Smoking as well as the harm of SHS exposure, parents and other family members should quit Smoking or at least reduce Smoking at home.
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overestimation of peer Smoking prevalence predicts Smoking Initiation among primary school students in hong kong
Journal of Adolescent Health, 2011Co-Authors: M P Wang, T H LamAbstract:Abstract Purpose To investigate the relationship between perceived prevalence of Smoking and Smoking Initiation among Hong Kong primary second- to fourth-grade-students. Methods A cohort of 2,171 students was surveyed in 2006 and again in 2008. Students who perceived ever-Smoking prevalence in peers as "none" or "some" were considered as correct (reference group), whereas those who perceived it as "half" (overestimation) or "most/all" (gross overestimation) were considered as incorrect. Results At baseline, overestimation was found to be cross-sectionally associated with ever-Smoking ( p Conclusion Overestimation of the prevalence of peer Smoking predicted Smoking Initiation among children. Interventions should be carried out to evaluate whether correcting children's overestimation of peer Smoking could reduce Smoking Initiation.
David Mendez - One of the best experts on this subject based on the ideXlab platform.
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finding the optimal mix of Smoking Initiation and cessation interventions to reduce Smoking prevalence
PLOS ONE, 2019Co-Authors: Ruoyan Sun, David MendezAbstract:There are more than one billion smokers globally according to the World Health Organization (WHO) report in 2017. Every year tobacco use causes nearly 6 million deaths worldwide. To deal with the Smoking epidemic, society needs to invest resources efficiently. In this paper we introduce an optimal control model to determine the optimal mix of Smoking Initiation and cessation interventions to reduce Smoking. We construct the model to reach a Smoking prevalence target within a specific time horizon while minimizing cost. Our performance measure captures the cost of policy implementation over time, adjusting for inflation and social discounting. The analytical solutions to the model are presented in forms of ordinary differential equations (ODE). We then conduct several numerical simulations using data from the National Health Interview Survey (NHIS) and empirical studies. We first present analytical solutions for our model to solve for the optimal mix of Smoking interventions. Then we simulate a public health policy to achieve 5% Smoking prevalence in the US by 2030 using different combinations of real-life interventions. We examine the optimal trajectories, allocative efficiency and annual total cost of Smoking cessation and Initiation interventions. We find consistent results across all simulations. Our specific example reveals that the most efficient way to reach stated goal is by targeting cessation interventions first, and then gradually shifting resources to Initiation interventions over time. While our numerical results are specific to the intervention we selected, our framework can be easily expanded to consider other potential interventions. We discuss the implications of our approach for the formulation of dynamic public health policies.
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e cigarettes comparing the possible risks of increasing Smoking Initiation with the potential benefits of increasing Smoking cessation
Nicotine & Tobacco Research, 2019Co-Authors: Kenneth E Warner, David MendezAbstract:Introduction The public health community is divided regarding electronic cigarettes. Skeptics emphasize potential vaping-induced increases in Smoking among children and possible health hazards for adults. Enthusiasts consider e-cigarettes much less dangerous than Smoking and believe they increase adult Smoking cessation. We compare potential health benefits and costs to put these two perspectives in context. Methods Using a dynamic model that tracks the US adult population's Smoking status and Smoking-related deaths over time, we simulate the effects of vaping-induced Smoking Initiation and cessation on life-years saved or lost to the year 2070. The base case assumes that vaping annually increases Smoking Initiation by 2% and Smoking cessation by 10%. Sensitivity analyses raise the Initiation rate increase to 6% while decreasing the cessation rate increase to 5%. Sensitivity analyses also test vaping's reducing the health benefits of quitting Smoking by 10%. Results With base-case assumptions, the population gains almost 3.3 million life-years by 2070. If all people who quit Smoking by vaping lose 10% of the benefit of quitting Smoking, the net life-year gain falls to 2.4 million. Under worst-case assumptions, in which vaping increases Smoking Initiation by 6% and cessation by 5%, and vaping-induced quitters lose 10% of the health benefits, the population gains over 580000 life-years. Conclusion Potential life-years gained as a result of vaping-induced Smoking cessation are projected to exceed potential life-years lost due to vaping-induced Smoking Initiation. These results hold over a wide range of plausible parameters. Implications Our analysis strongly suggests that the upside health benefit associated with e-cigarettes, in terms of their potential to increase adult Smoking cessation, exceeds their downside risk to health as a result of their possibly increasing the number of youthful Smoking initiators. Public messaging and policy should continue to strive to reduce young people's exposure to all nicotine and tobacco products. But, they should not do so at the expense of limiting such products' potential to help adult smokers to quit.
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an application of the continuous opinions and discrete actions coda model to adolescent Smoking Initiation
PLOS ONE, 2017Co-Authors: Ruoyan Sun, David MendezAbstract:We investigated the impact of peers’ opinions on the Smoking Initiation process among adolescents. We applied the Continuous Opinions and Discrete Actions (CODA) model to study how social interactions change adolescents’ opinions and behaviors about Smoking. Through agent-based modeling (ABM), we simulated a population of 2500 adolescents and compared Smoking prevalence to data from 9 cohorts of adolescents in the National Survey on Drug Use and Health (NSDUH) from year 2001 till 2014. Our model adjusts well for NSDUH data according to pseudo R2 values, which are at least 96%. Optimal parameter values indicate that adolescents exhibit imitator characteristics with regard to Smoking opinions. The imitator characteristics suggests that teenagers tend to update their opinions consistently according to what others do, and these opinions later translate into Smoking behaviors. As a result, peer influence from social networks plays a big role in the Smoking Initiation process and should be an important driver in policy formulation.