title: Increasing prevalence of electronic cigarette use among smokers hospitalized in 5 US cities, 2010-2013.
abstract: BACKGROUND
  Little is known about the pattern of electronic cigarette (e-cigarette) use over time or among smokers with medical comorbidity.
  
  
  METHODS
  We assessed current cigarette smokers' use of e-cigarettes during the 30 days before admission to 9 hospitals in 5 geographically dispersed US cities: Birmingham, AL; Boston, MA; Kansas City, KS; New York, NY; and Portland, OR. Each hospital was conducting a randomized controlled trial as part of the NIH-sponsored Consortium of Hospitals Advancing Research on Tobacco (CHART). We conducted a pooled analysis using multiple logistic regression to examine changes in e-cigarette use over time and to identify correlates of e-cigarette use.
  
  
  RESULTS
  Among 4,660 smokers hospitalized between July 2010 and December 2013 (mean age 57 years, 57% male, 71% white, 56% some college, average 14 cigarettes/day), 14% reported using an e-cigarette during the 30 days before admission. The prevalence of e-cigarette use increased from 1.1% in 2010 to 10.3% in 2011, 10.2% in 2012, and 18.4% in 2013; the increase was statistically significant (p < .0001) after adjustment for age, sex, education, and CHART study. Younger, better educated, and heavier smokers were more likely to use e-cigarettes. Smokers who were Hispanic, non-Hispanic black, and who had Medicaid or no insurance were less likely to use e-cigarettes. E-cigarette use also varied by CHART project and by geographic region.
  
  
  CONCLUSIONS
  E-cigarette use increased substantially from 2010 to 2013 among a large sample of hospitalized adult cigarette smokers. E-cigarette use was more common among heavier smokers and among those who were younger, white, and who had higher socioeconomic status.
authors.affiliation: Tobacco Research and Treatment Center, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA; nrigotti@partners.org.
authors.forename: Nancy A
authors.initials: NA
authors.lastname: Rigotti
authors.affiliation: Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL;
authors.forename: Kathleen F
authors.initials: KF
authors.lastname: Harrington
authors.affiliation: Department of Preventive Medicine and Public Health, University of Kansas School of Medicine, Kansas City, KS;
authors.forename: Kimber
authors.initials: K
authors.lastname: Richter
authors.affiliation: Kaiser Permanente Center for Health Research, Portland, OR;
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Fellows
authors.affiliation: Division of General Internal Medicine, New York University School of Medicine, New York, NY;
authors.forename: Scott E
authors.initials: SE
authors.lastname: Sherman
authors.affiliation: Division of General Internal Medicine, New York University School of Medicine, New York, NY;
authors.forename: Ellie
authors.initials: E
authors.lastname: Grossman
authors.affiliation: Tobacco Research and Treatment Center, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA;
authors.forename: Yuchiao
authors.initials: Y
authors.lastname: Chang
authors.affiliation: Division of General Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Hilary A
authors.initials: HA
authors.lastname: Tindle
authors.affiliation: Division of General Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Ylioja
mesh_terms: D000328:Adult; D000367:Age Factors; D002947:Cities; D066300:Electronic Nicotine Delivery Systems / Q000706:statistics & numerical data*; D005006:Ethnicity; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010343:Patient Admission / Q000706:statistics & numerical data*; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology*; D016540:Smoking Cessation / Q000379:methods*; D014481:United States / Q000453:epidemiology