title: E-cigarette use and subsequent cigarette and marijuana use among Hispanic young adults.
abstract: Electronic cigarettes (e-cigarettes) could have a multifaceted effect on public health by changing the likelihood that: (a) non-smokers and non-users of marijuana subsequently transition to cigarette and marijuana use, respectively, and/or: (b) cigarette smokers subsequently quit smoking. We analyzed data from a longitudinal study of Hispanic young adults in Los Angeles, California to determine whether e-cigarette use is associated with subsequent cigarette or marijuana use over a one-year period.
  
  
  
  Survey data were collected from 1332 Hispanic young adults (59% female, mean age=22.7 years, SD=0.39 years) in 2014 and 2015. Logistic regression analyses examined the association between e-cigarette use in 2014 and cigarette/marijuana use in 2015, controlling for age, sex, and other substance use.
  
  
  
  In 2014, prevalence of past-month use was 9% for e-cigarettes, 21% for cigarettes, and 23% for marijuana. Among past-month cigarette nonsmokers in 2014, those who were past-month e-cigarette users in 2014 were over 3 times more likely to be past-month cigarette smokers in 2015, compared with those who did not report past-month e-cigarette use in 2014 (26% vs. 7%; OR=3.32, 95% CI=1.55, 7.10). Among past-month marijuana non-users in 2014, those who were past-month e-cigarette users in 2014 were nearly 2 times more likely to be past-month marijuana users in 2015 (24% vs. 12%;OR=1.97, 95% CI=1.01, 3.86). Among past-month cigarette and marijuana users in 2014, e-cigarette use in 2014 was not associated with a change cigarette and marijuana use, respectively, in 2015.
  
  
  
  Among Hispanic young adults, e-cigarettes could increase the likelihood of transitioning from non-user to user of cigarettes or marijuana and was not associated with smoking cessation.
authors.affiliation: University of Southern California Keck School of Medicine, 2001 N. Soto St., SSB 302, Los Angeles, CA 90089, United States. Electronic address: unger@usc.edu.
authors.forename: Jennifer B
authors.initials: JB
authors.lastname: Unger
authors.affiliation: University of Southern California Keck School of Medicine, 2001 N. Soto St., SSB 302, Los Angeles, CA 90089, United States.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Soto
authors.affiliation: University of Southern California Keck School of Medicine, 2001 N. Soto St., SSB 302, Los Angeles, CA 90089, United States.
authors.forename: Adam
authors.initials: A
authors.lastname: Leventhal
mesh_terms: D000293:Adolescent; D000328:Adult; D066300:Electronic Nicotine Delivery Systems / Q000706:statistics & numerical data* / Q000639:trends; D005260:Female; D006630:Hispanic or Latino / Q000523:psychology*; D006801:Humans; D008137:Longitudinal Studies; D015141:Los Angeles / Q000208:ethnology; D008297:Male; D008385:Marijuana Smoking / Q000208:ethnology* / Q000523:psychology / Q000639:trends; D012907:Smoking / Q000208:ethnology* / Q000523:psychology* / Q000639:trends; D016540:Smoking Cessation / Q000208:ethnology / Q000523:psychology; D011795:Surveys and Questionnaires; D062789:Tobacco Products; D055815:Young Adult
keywords: Electronic cigarettes; Hispanic; Marijuana; Young adults