Jamie Tam
University of Michigan
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Tobacco Control | 2012
Kenneth E. Warner; Jamie Tam
Objectives To assess progress in tobacco control policy research and the relevance of research to policymaking. Methods Over 100 experts were surveyed about their opinions on the body of research existing in 1992 and 2011 concerning 11 areas of tobacco control policy, the state of policy implementation in both years, the extent to which research has affected policy adoption and how experience with policy has influenced research. Case studies of how research and policy implementation have interacted were developed. Results The body of research was not judged ‘substantial’ in any of the policy areas in 1992. In 2011, 6 of the 11 areas were evaluated as substantial. None ranked as substantial regarding policy implementation in 1992, but by 2011 half were so ranked for developed countries; in low-income and middle-income countries policy implementation moved from very low to moderate. Respondents judged the role of research in actual policymaking as ‘substantial’ regarding clean indoor air, taxation and cessation treatment policy. Case studies illustrate how research can directly affect policy (taxation), how policy and research can have iterative effects (clean indoor air), and how research and policy interact in the case of novel policies (graphic cigarette pack warnings). The role of research in the formulation of the Framework Convention on Tobacco Control is also examined. Conclusions Policy research goals established in 1992 have been largely realised. For select tobacco control policies, research has made truly important contributions to saving lives. Evidence-based policy adoption will continue to be essential to minimising the toll of tobacco, especially in the worlds poorer countries.
American Journal of Preventive Medicine | 2016
Jamie Tam; Kenneth E. Warner; Rafael Meza
INTRODUCTION People with serious mental illness experience substantially reduced life expectancy, likely due in part to their higher smoking rates relative to the general population. However, the extent to which smoking affects their life expectancy, independent of mental illness, is unknown. This study quantifies the potential contribution of smoking to reduced life expectancy among individuals with serious psychological distress (SPD), a measure that screens for serious mental illness in national surveys. METHODS A cohort of 328,110 U.S. adults was examined using the 1997-2009 National Health Interview Surveys linked to the 2011 National Death Index. Cox models were used to estimate mortality hazard ratios for current smoking, former smoking, and SPD and construct life tables by smoking and SPD status. The smoking-attributable fraction of deaths by SPD status was calculated. Analyses were conducted in 2015. RESULTS Among those with SPD, being a current smoker doubles the risk of death. Current smokers with SPD lose 14.9 years of life relative to never smokers without SPD. Among never smokers, having SPD reduces life expectancy by 5.3 years. Thus, smoking may account for up to two thirds of the difference in life expectancy between smokers with SPD and never smokers without SPD. One third of deaths among those with SPD can be attributed to smoking. CONCLUSIONS The life expectancy difference between current smokers with SPD and never smokers without SPD is primarily due to smoking. Aiding individuals with serious mental illness to avoid smoking will translate into sizeable gains in life expectancy.
Epidemiology | 2016
Sarah Cherng; Jamie Tam; Paul J. Christine; Rafael Meza
Background: Electronic cigarette (e-cigarette) use has increased rapidly in recent years. Given the unknown effects of e-cigarette use on cigarette smoking behaviors, e-cigarette regulation has become the subject of considerable controversy. In the absence of longitudinal data documenting the long-term effects of e-cigarette use on smoking behavior and population smoking outcomes, computational models can guide future empirical research and provide insights into the possible effects of e-cigarette use on smoking prevalence over time. Methods: Agent-based model examining hypothetical scenarios of e-cigarette use by smoking status and e-cigarette effects on smoking initiation and smoking cessation. Results: If e-cigarettes increase individual-level smoking cessation probabilities by 20%, the model estimates a 6% reduction in smoking prevalence by 2060 compared with baseline model (no effects) outcomes. In contrast, e-cigarette use prevalence among never smokers would have to rise dramatically from current estimates, with e-cigarettes increasing smoking initiation by more than 200% relative to baseline model estimates to achieve a corresponding 6% increase in smoking prevalence by 2060. Conclusions: Based on current knowledge of the patterns of e-cigarette use by smoking status and the heavy concentration of e-cigarette use among current smokers, the simulated effects of e-cigarettes on smoking cessation generate substantially larger changes to smoking prevalence compared with their effects on smoking initiation.
Nicotine & Tobacco Research | 2016
David Mendez; Jamie Tam; Gary A. Giovino; Alex Tsodikov; Kenneth E. Warner
Introduction We examine the trajectory of adult smoking prevalence in the United States over the period 1990-2014 to investigate whether the smoking cessation rate has changed during this period. Methods We employ a dynamic model of smoking prevalence, and data from the National Health Interview Survey (NHIS) and the National Survey on Drug Use and Health (NSDUH), to estimate the adult cessation rate in 6-year intervals. We use weighted nonlinear least squares to perform the estimation. We then employ a meta-regression model to test whether the cessation rate has increased. Results The annual cessation rate has increased from 2.4% in 1990 to 4.5% in 2014 according to the NHIS data, and from 3.2% in 2002 to 4.2% in 2014 according to the NSDUH data. The increasing trend is statistically significant (p value = 1.57×10-6) and the two independent surveys produced nearly identical results, which makes it unlikely that our findings are a product of chance. Conclusions Our analysis finds that the smoking cessation rate in the United States has almost doubled since 1990. This increase is responsible for at least 2 million fewer smokers in 2014. If current conditions persist, by the year 2020 the increase in cessation rates will be responsible for 3.5 million fewer smokers. Our findings can assist in predicting the future path of the smoking epidemic and determining the correct allocation of resources to eradicate it. Implications We show that the adult smoking cessation rate has greatly increased since 1990. We demonstrate this by studying prevalence trajectories from two independent population surveys, which yielded nearly identical results. Different from other studies, we focus on permanent quit rates (net of relapses) which we estimate from a dynamic model of prevalence. Our results do not stem from self-reported quitting behavior, but from the analysis of observed prevalence and its inherent variability. Our findings can contribute to predicting the future path of the smoking epidemic and to determining the optimal allocation of resources to eradicate it.
Tobacco Control | 2014
Kenneth E. Warner; Jamie Tam; Sarah M Koltun
Background Research has contributed significantly to tobacco control in high-income nations, but has not yet played a comparable role in low- and middle-income countries (LMIC). In recent years, efforts have been devoted to building research capacity in LMICs. Using publication in Tobacco Control as a proxy for all tobacco control research, we examine whether research articles authored by scholars from LMICs and about LMIC issues have increased over the Journals history. Methods We examined every issue of Tobacco Control from 1992 to 2011, coding contributions as to their authorship (LMIC, high-income country, or both), and whether they covered tobacco control issues in LMICs. We included all the following journal categories: Original/Research articles, Brief reports, Reviews, Letters to the editor, Special communications, Commentaries, and Editorials. Results We divided the Journals first 20 years into four 5-year periods. There was no statistically significant change in LMIC authorship or LMIC issue coverage during the first three periods. From those three periods combined (1992–2006), to the most recent 5-year period (2007–2011), articles including any LMIC authors increased from 7.2% to 22.7% (p<0.05) of all original research articles; lead authorship by LMIC scholars increased from 4.0% to 13.7% (p<0.05); and coverage of LMIC issues rose from 10.1% to 30.9% (p<0.05). Similar findings resulted when combining all the journal categories. Conclusions Efforts to expand research by LMIC authors and about LMIC issues have begun to bear fruit, with a recent substantial increase. Still, the centrality of LMICs in the global tobacco pandemic implies that this progress only begins to address the enormous need.
Tobacco Control | 2014
Jamie Tam; Corne van Walbeek
Background Namibia is typical of low-income and middle-income countries with growing tobacco use, but with limited capacity to impose comprehensive tobacco control legislation. Despite initiating dialogue on national tobacco control policy in 1991, the country took nearly 20 years to pass the Tobacco Products Control Act. Objective To use Namibia as a case study to illustrate challenges faced by low-income countries working to forward tobacco control legislation. Method Face-to-face and telephonic interviews were conducted with 13 bureaucrats and advocates currently or previously engaged in tobacco-related work in Namibia. Tobacco-related news articles from national newspapers were examined. Results The constitutional obligation of the government to promote public health laid the foundation for Namibias tobacco control policy. Staff capacity constraints greatly delayed the passing of tobacco control legislation. It is unclear what influence the tobacco industrys involvement as a stakeholder had on policy; however, in at least one instance, the tobacco industry actively misled government. Namibias ratification of the Framework Convention on Tobacco Control was instrumental in passing legislation that meets most provisions of the international treaty. The media have generally played a supportive role in pushing the government to pass tobacco control legislation. Conclusions The fact that Namibia was able to pass fairly comprehensive tobacco control legislation with such meagre resources is commendable. The government must now implement the regulations that make the legislation effective. Tobacco control progress in low-income and middle-income nations can be encouraged through use of the media and improved staff and legal capacity within health ministries.
Nicotine & Tobacco Research | 2014
Jamie Tam; Kenneth E. Warner; Brenda W. Gillespie; John Gillespie
INTRODUCTION U.S. smoking prevalence has been declining over the last several decades. During this time, the population has also experienced changes in its demographic composition, as Americans are living longer and becoming increasingly racially and ethnically diverse. Since smoking rates vary across age and race/ethnicity groups, demographics alone could contribute to changes in smoking prevalence among the general population. We examined the effect of changing age and race/ethnicity distributions on total smoking prevalence from 1980 to 2010. METHODS Using the National Health Interview Survey weighting scheme, we applied the distribution of smokers across age and race/ethnicity categories for the years 1980 and 2010 to the distribution of adults in those categories for both years. The total number of smokers was summed to determine resulting smoking prevalence. RESULTS The combined effect of aging and the changing racial/ethnic composition of the U.S. population has contributed 2.1% points to the decline in smoking prevalence. If the age and racial/ethnic demographic composition had not changed since 1980, smoking prevalence would have been 21.3% in 2010 (with rounding)--statistically significantly higher than the reported 19.3%. Of the 3 demographic factors we considered (age, race, and ethnicity), ethnicity--specifically the rising share of Hispanics in the population--is the most important contributor to declines in smoking. CONCLUSIONS Our changing demographics have had an impact on smoking prevalence over the last 3 decades. Future declines in smoking may be driven even more by the aging of the population and increasing racial and ethnic diversity.
Preventive medicine reports | 2018
Yan Kwan Lau; Jamie Tam; Nancy L. Fleischer; Rafael Meza
Research on the role of neighbourhood-level deprivation in low- and middle-income countries with respect to tobacco use is relatively nascent. In South Africa, where race and deprivation are closely linked due to the history of apartheid, smoking disparities exist by individual risk factors such as gender, race, and socioeconomic status. However, less is known about how community-level factors affect smoking disparities in the country, or how the relationship between deprivation and smoking differs by race. We used data from the 2008 South African National Income Dynamics Study (NIDS) and Poisson generalised estimating equations to assess the relationship between neighbourhood deprivation and current smoking for individuals nested within neighbourhoods, while controlling for individual-level and household-level covariates. Subgroup analyses for racial categories Black and Coloured were performed. We found that the relationship between neighbourhood deprivation and smoking prevalence was non-linear: the smoking prevalence ratio was highest among those in the middle range for our deprivation index, and lower at extremely high and low levels of deprivation. Both Black and Coloured subsamples exhibited this inverted U-shape, although the relationship was weaker in the latter group. That the relationship between neighbourhood deprivation and smoking is non-linear contrasts with what has been found in high-income countries, where the relationship between neighbourhood deprivation and smoking is linear. Moreover, these findings are relevant to assess the potential differential impact of smoking interventions as a function of socioeconomic and environmental context.
BMJ Open | 2018
Jamie Tam; David T. Levy; Jihyoun Jeon; John Clarke; Scott Gilkeson; Tim Hall; Eric J. Feuer; Theodore R. Holford; Rafael Meza
Introduction Smoking remains the leading cause of preventable death in the USA but can be reduced through policy interventions. Computational models of smoking can provide estimates of the projected impact of tobacco control policies and can be used to inform public health decision making. We outline a protocol for simulating the effects of tobacco policies on population health outcomes. Methods and analysis We extend the Smoking History Generator (SHG), a microsimulation model based on data from the National Health Interview Surveys, to evaluate the effects of tobacco control policies on projections of smoking prevalence and mortality in the USA. The SHG simulates individual life trajectories including smoking initiation, cessation and mortality. We illustrate the application of the SHG policy module for four types of tobacco control policies at the national and state levels: smoke-free air laws, cigarette taxes, increasing tobacco control programme expenditures and raising the minimum age of legal access to tobacco. Smoking initiation and cessation rates are modified by age, birth cohort, gender and years since policy implementation. Initiation and cessation rate modifiers are adjusted for differences across age groups and the level of existing policy coverage. Smoking prevalence, the number of population deaths avoided, and life-years gained are calculated for each policy scenario at the national and state levels. The model only considers direct individual benefits through reduced smoking and does not consider benefits through reduced exposure to secondhand smoke. Ethics and dissemination A web-based interface is being developed to integrate the results of the simulations into a format that allows the user to explore the projected effects of tobacco control policies in the USA. Usability testing is being conducted in which experts provide feedback on the interface. Development of this tool is under way, and a publicly accessible website is available at http://www.tobaccopolicyeffects.org.
American Journal of Preventive Medicine | 2018
Jamie Tam; Kenneth E. Warner
INTRODUCTION There is concern that youth e-cigarette use may serve as a gateway to cigarette smoking, and that nicotine exposure may harm brain development. It is therefore important to know how much nonsmoking youth perceive being exposed to nicotine through e-cigarettes. METHODS Data on smoking and vaping from the 2016 Monitoring the Future survey of eighth, tenth, and 12th grade students were analyzed in 2017. The weighted percentage distributions of self-reported e-cigarette mist last inhaled were calculated according to ever-smoking status and past 30-day smoking frequency. Chi-square tests of the association between smoking status and use of e-cigarettes perceived to contain nicotine, marijuana or hash oil, or just flavoring were performed. Never smokers and regular smokers were compared regarding the type of e-cigarette mist they believe they last used. RESULTS A significant relationship exists between smoking behavior and reportedly vaping nicotine (p<0.01) or just flavors (p<0.01). With increasing smoking intensity, an increasing proportion of students report they are vaping nicotine; a decreasing proportion report just flavors. Among 12th graders, prevalence of vaping nicotine is lowest among never smokers and non-current smokers (14.3% and 18.1%) and highest among current and frequent smokers (61.3% and 60.9%, p<0.01). Substantially larger proportions of never smokers and 30-day nonsmokers report vaping just flavors (76.0% and 69.6%) compared with regular or frequent smokers (31.0% and 29.3%, p<0.01). CONCLUSIONS Most nonsmoking students perceive limited nicotine exposure from vaping. Future research should evaluate the accuracy of self-reported e-cigarette nicotine content and monitor students who are consciously using nicotine-based e-cigarettes.