Marijuana use in U.S. teen drivers: a comparison of a road-side survey of reported use and fluid tests for tetrahydrocannabinol (THC).

BACKGROUND: Although the growth of state-level legalization of marijuana is aimed at increasing availability for adults and the chronically ill, one fear is that this trend may also increase accessibility in younger populations. The objectives of this study are to evaluate marijuana use in teen driver study participants and to compare their survey self-reported use with oral fluid and blood tests for psychoactive metabolites of tetrahydrocannabinol (THC). METHODS: The National Roadside Survey (NRS) of 2013-2014 was used to examine marijuana use in drivers aged 16-19 years. Of 11,100 drivers surveyed at 300 U.S. locations in 24 states, 718 were 16-19 years, and 666 (92.8%) provided oral fluid and/or blood. We examined weighted and unweighted data, but present unweighted findings. Kappa statistics, Chi square, and multivariable logistic regressions were used to assess agreement, associations and independent predictors of outcomes. RESULTS: More than one-quarter (203/718) of teen drivers reported either using marijuana in the last year or were THC positive. Overall incidence of a THC positive fluid test was 13.7%. In addition to 175 (27.3%) teen drivers who reported use in the last year, 28 (4.4%) who denied using in the past year, tested positive for THC. Of 45 teen drivers reporting use in the last 24 h, more than two-thirds (71.1%) were THC positive. Disagreement between the oral and blood test for 305 teen drivers who had both tests was 17 (5.6%), with a Kappa of 0.78 (95% CI 0.69-0.88). Of THC-positive drivers, nearly 20% started drinking alcohol by age 14 and more than 70% by age 16. Age, gender- and income-adjusted independent predictors of a positive THC test included survey completion during the school year (OR 3.2, 95% CI 1.6-6.2), survey-reported marijuana use in last year (OR 5.3, 95% CI 3.0-9.2), current smoker (OR 2.1, 95% CI 1.1-3.7), and alcohol consumption before age 16 (OR 2.3, 95% CI 1.1-3.7). CONCLUSIONS: Although specific THC thresholds for safe driving have not been established, taken in the context of teen crash statistics, THC documented impairments and rapidly relaxing marijuana laws, these findings suggest the need for increased vigilance and stepped-up surveillance in teen drivers.

The Advertising Strategies of Early E-cigarette Brand Leaders in the United States.

OBJECTIVES: We examined differential advertising strategies used by 4 major United States e-cigarette companies with differential affiliations with the traditional tobacco industry (ie, Njoy - independent, Blu - acquired, Vuse and MarkTen - launched by cigarette companies) over time. METHODS: We conducted a mixed-methods study regarding e-cigarette adspend, adspend per media channel (eg, TV, print), and advertising messaging strategies among these 4 top e-cigarette brands from January 2013 through December 2015. RESULTS: E-cigarette adspend increased from $59 million in 2013 to $91 million in 2014, followed by a sharp decline to $37 million in 2015. These companies showed distinct spending trajectories overall and across media channels, with Njoy and Vuse spending a higher proportion of their dollars on TV and Blu and MarkTen spending more on print. Marketing messages were also different by company. Key themes included switching from cigarettes (particularly by Njoy and Blu), circumventing smoke-free policies (particularly by Blu), and technological advancement (particularly by Vuse and MarkTen). CONCLUSIONS: These e-cigarette brands have shifted their adspend, use of media channels, and advertising messaging strategies over time. Some differing strategies may reflect the different affiliations of each brand to the traditional cigarette industry.

Reasons for Polytobacco Use among Young Adults: Scale Development and Validation.

INTRODUCTION: Limited research has examined reasons for polytobacco use, an increasing public health problem, particularly among young adults. We examined reasons for polytobacco use among users of more than one tobacco product in the past 4 months enrolled in an ongoing six-wave longitudinal study of 3,418 students aged 18-25 from seven US colleges and universities. METHODS: An expert panel generated items related to reasons for polytobacco use, included in Wave 3 (administered in Summer 2015). Participants reporting use of more than one tobacco product in the past four months (n=540) were asked to complete the Reasons for Polytobacco Use scale and measures related to tobacco/nicotine use/dependence, use motives, perceptions of tobacco, parental/friend use, other substance use, and mental health. We conducted a factor analysis and then examined convergent and discriminant validity for the derived factors. RESULTS: Our sample was an average age of 20.40 (SD=1.84), 48.0% male, and 21.9% Black. Four factors were identified: Instrumentality, Social Context, Displacement, and Experimentation. Instrumentality was the only factor associated with little cigar/cigarillo and marijuana use. Displacement and Social Context showed similar associations; however, Social Context was associated with having friends who used tobacco while Displacement was not. Experimentation was associated with greater perceived addictiveness and harm of using tobacco products as well as greater perceived social acceptability of tobacco use. CONCLUSIONS: Each of the four factors identified demonstrated unique convergent and discriminant validity. The use of this scale to characterize polytobacco using young adults may help inform and target cessation or prevention interventions.