Former smokers who quit within the past year are four times more likely to be daily users of e-cigarettes

In "Patterns Of Electronic Cigarette Use Among Adults in the United States," published earlier this month in Nicotine & Tobacco Research, researchers analyzed data from the 2014 National Health Interview Survey (NHIS) of 36,697 U.S. adults age 18 and over to assess daily e-cigarette use and its association with demographic characteristics and cigarette smoking status. The researchers analyzed e-cigarette use among adults who are current daily cigarette smokers, current some day cigarette smokers, recent quitters -- those who quit within the last year, former smokers who quit two to three years ago, former smokers who quit four or more years ago and never smokers.

Consistent with a report recently released by the U.S. Centers for Disease Control and Prevention (CDC), the authors found that, overall, 12.6 percent of all adults report having ever tried e-cigarettes. The Rutgers/Truth Initiative study goes further by examining daily use of e-cigarettes and found that nearly half (49 percent) of daily cigarette smokers have ever tried e-cigarettes. "The highest prevalence of daily e-cigarette use we observed was among current smokers and former smokers who quit within the past year. The recent quitters are four times more likely to be daily users of e-cigarettes than current cigarette smokers (13 percent vs. 3.5 percent)," said Cristine Delnevo, the study's lead author. "This study is in line with other recent evidence that regular, daily e-cigarette use may help some smokers quit cigarettes," Delnevo added.

The researchers also found that while any e-cigarette use was higher among young adults, daily e-cigarette use was more common among adults over age 25 than among young adults aged 18-24. They noted that e-cigarette experimentation was extremely low for adults who never smoked cigarettes or who quit more than four years ago. Among their key takeaways: e-cigarettes do not appear to attract young adults, non-smokers or promote relapse among longer-term former smokers.

"The finding that daily e-cigarette use is less common among 18-24 year olds and never smokers is good news," according to David Abrams, executive director of the Schroeder Institute. "It suggests that e-cigarettes could be used to displace use of much more deadly cigarettes among smokers and could generate an impressive public health benefit in terms of lives saved. It is important to be clear, however, that e-cigarettes deliver nicotine, an addictive stimulant. They are not appropriate products for children and youth."

The authors caution that more precise measures of when, why and how e-cigarette use was initiated and how it is continuing are needed, and that such questions as well as longitudinal cohort studies may help researchers and policymakers better understand issues such as dual use, exclusive e-cigarette use and e-cigarette use as a potential cessation aid.