Importance Electronic cigarette (e cigarette) use is increasing rapidly among adolescents, and e cigarettes are currently unregulated.

Objective To examine e cigarette use and conventional cigarette smoking.

Design, Setting, and Participants Cross sectional analyses of survey data from a representative sample of US middle and high school students in 2011 (n 17 353) and 2012 (n 22 529) who completed the 2011 and 2012 National Youth Tobacco Survey.

Exposures Ever and current e cigarette use.

Main Outcomes and Measures Experimentation with, ever, and current smoking, and smoking abstinence.

Results Among cigarette experimenters ( 1 puff), ever e cigarette use was associated with higher odds of ever smoking cigarettes ( 100 cigarettes odds ratio OR 6.31 95% CI, 5.39 7.39) and current cigarette smoking (OR 5.96 95% CI, 5.67 6.27). Current e cigarette use was positively associated with ever smoking cigarettes (OR 7.42 95% CI, 5.63 9.79) and current cigarette smoking (OR 7.88 95% CI, 6.01 10.32). In 2011, current cigarette smokers who had ever used e cigarettes were more likely to intend to quit smoking within the next year (OR 1.53 95% CI, 1.03 2.28). Among experimenters with conventional cigarettes, ever use of e cigarettes was associated with lower 30 day (OR 0.24 95% CI, 0.21 0.28), 6 month (OR 0.24 95% CI, 0.21 0.28), and 1 year (OR 0.25 95% CI, 0.21 0.30) abstinence from cigarettes. Current e cigarette use was also associated with lower 30 day (OR 0.11 95% CI, 0.08 0.15), 6 month (OR 0.11 95% CI, 0.08 0.15), and 1 year (OR 0.12 95% CI, 0.07 0.18) abstinence. Among ever smokers of cigarettes ( 100 cigarettes), ever e cigarette use was negatively associated with 30 day (OR 0.61 95% CI, 0.42 0.89), 6 month (OR 0.53 95% CI, 0.33 0.83), and 1 year (OR 0.32 95% CI, 0.18 0.56) abstinence from conventional cigarettes. Current e cigarette use was also negatively associated with 30 day (OR 0.35 95% CI, 0.18 0.69), 6 month (OR 0.30 95% CI, 0.13 0.68), and 1 year (OR 0.34 95% CI, 0.13 0.87) abstinence.

Conclusions and Relevance Use of e cigarettes was associated with higher odds of ever or current cigarette smoking, higher odds of established smoking, higher odds of planning to quit smoking among current smokers, and, among experimenters, lower odds of abstinence from conventional cigarettes. Use of e cigarettes does not discourage, and may encourage, conventional cigarette use among US adolescents.

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The price of cigarettes in the european union — montes and villalbi 10 (2): 135 — tobacco control

Cannabis use may increase the likelihood of becoming addicted to nicotine, suggests a study in rats funded by the National Institute on Drug Abuse.

Data from previous epidemiologic studies have suggested that people who smoke marijuana are more likely to become addicted to cigarettes, but the reason why was unclear.

To probe whether biological factors may be involved, the researchers injected rats with tetrahydrocannabinol (THC), the main psychoactive component of cannabis, for 3 days (Panlilio LV et al. Neuropsychopharmacology. doi 10.1038/npp.2013.16 published online January 10, 2013 ). A week later the investigators implanted catheters in the animals to give them an intravenous dose of nicotine or a placebo when they completed a task. Of rats in the nicotine group, 94% learned to complete the task to get their dose, compared with 65% of the placebo group. When the rats had to work harder to obtain the dose, those in the nicotine group were more likely to persist.