A Naturalistic, Randomized Pilot Trial of E-Cigarettes: Uptake, Exposure, and Behavioral Effects.

Most studies of electronic nicotine delivery systems (ENDS) compare self-selected users versus nonusers. The few randomized studies to date generally support a positive impact on reducing smoking behavior, but these studies are focused on guided ENDS use. This study presents a randomized, naturalistic trial of ENDS with prospective outcomes of uptake and behavioral changes in smoking. Adult smokers with minimal ENDS history were randomized in a 2:1 ratio to receive product for 3 weeks ( = 46), or not ( = 22). Changes in nicotine delivery (16 vs. 24 mg), midway through the study allowed a compelling opportunity to examine two ENDS products compared with the control group. Primary outcomes, assessed via daily diaries during sampling period and in-person laboratory visits over 4 months, included uptake and usage of ENDS, cessation-related outcomes, and exposure to smoke constituents. All ENDS participants tried product at least once, with 48% of 24 mg and 30% of 16 mg using their assigned product for the entire sampling period. Within the 24 mg ENDs group, 57% made an independent purchase of ENDS, versus 28% of 16 mg, and 14% of control participants ( = 0.01). Smokers in both ENDS groups significantly reduced their smoking, whereas control participants did not ( = 0.03). Cessation behaviors (quit attempts, biologically verified abstinence) numerically but not statistically favored ENDS participants. Results suggest that cigarette smokers are willing to use ENDS with trends toward reduced cigarette smoking and positive changes in cessation-related behaviors. Randomized, naturalistic trials such as presented herein are needed to understand the population impact of e-cigarettes. .