Examining e-cigarette purchases and cessation in a consumer panel of smokers.

Objectives: Examine correlates of initiation of e-cigarette use among smokers and determine the impact of e-cigarette use on cessation among smokers in a national U.S. consumer panel.

Methods: This study used the Nielsen Homescan Panel data from 2011 to 2013, augmented with state-specific measures of tobacco control activities, to examine 1) correlates of single and repeat e-cigarette purchasing among panelists currently purchasing cigarettes; and 2) correlates of "cessation". Participating panelists scanned all retail purchases, and Nielsen recorded over 3 million product types. The key explanatory variable for cessation was e-cigarette purchase. Parallel analysis was conducted for conventional nicotine replacement therapy (NRT) purchase. Cessation was defined as no purchases for at least 6 months and no subsequent purchases until the end of 2013. Analysis was conducted in 2015. E-cigarettes tracked by Nielsen during this period were cig-a-like products resembling tobacco cigarettes in appearance.

Results: Single e-cigarette purchase was associated with whether the panelist resided in a single person male household and bought a higher volume of cigarettes. Repeat purchase was associated with higher state cigarette taxes, less stringent state public smoke-free policies, lower cigarette prices, and more frequent cigarette purchasing. Cessation was associated with repeat e-cigarette purchasing, repeat NRT purchasing, younger age, lower monthly cigarette volume, less frequent purchasing of cigarettes, less recent cigarette purchase at baseline, and single e-cigarette purchase before baseline.

Conclusions: Both individual and policy variables were associated with e-cigarette use. Repeat e-cigarette purchase was associated with cigarette purchase discontinuation, as were various smoking intensity measures.