Electronic cigarettes, or e-cigarettes, were introduced into the U.S. market in recent years. However, little is known about the health impact of the product or the extent of its use. This study assessed the prevalence and correlates of awareness and ever-use of e-cigarettes among U.S. adults during 2010-2011. Data were obtained from the HealthStyles survey, a national consumer-based survey of U.S. adults aged ≥18 years old. In 2010, data collection for the HealthStyles survey was both mail-based (n = 4,184) and web-based (n = 2,505), and in 2011, web-based (n = 4,050) only. Estimates of awareness and ever-use of e-cigarettes were calculated overall and by sex, age, race/ethnicity, educational attainment, household income, region, and smoking status. In 2010, overall awareness of e-cigarettes was 38.5% (mail survey) and 40.9% (web survey); in 2011, awareness was 57.9% (web survey). Ever-use of e-cigarettes among all respondents was 2.1% in the 2010 mail survey, 3.3% in the 2010 web survey, and 6.2% in the 2011 web survey. Ever-use of e-cigarettes was significantly higher among current smokers compared with both former and never-smokers, irrespective of survey method or year. During 2010-2011, ever-use increased among both sexes, those aged 45-54 years, non-Hispanic Whites, those living in the South, and current and former smokers. Awareness and ever-use of e-cigarettes increased among U.S. adults from 2010 to 2011. In 2011, approximately 1 in 5 current smokers reported having ever-used e-cigarettes. Continued surveillance of e-cigarettes is needed for public health planning.
