Differences in Delay, but not Probability Discounting, in Current Smokers, E-cigarette Users, and Never Smokers

Abstract

Steeper delay discounting in substance abuse populations, compared to non-abusing populations, has been well-established in prior studies. Despite the growing interest in e-cigarettes as a novel and relatively understudied form of nicotine consumption, relatively little is known as to how e-cigarette users discount rewards compared to traditional cigarette smokers and never smokers. In the present study, we measured delay and probability discounting rates, as well as perceived risk inherent to a delayed reward, in current traditional cigarette smokers, e-cigarette users, and never smokers. We found that traditional cigarette smokers and e-cigarette users discounted delayed rewards at a similar rate-and both were steeper than never smokers. However, no differences were observed in probability discounting or in perceived risk inherent in reward delay.

Keywords: Delay discounting; E-cigarette; Probability discounting; Risk in delay; Smoking.

Fig. 1

Median indifference points (upper row) with corresponding mean areas under the curve (AUC, lower row) for delay (left column) and probability (center column) discounting. Data points for SPQ (right column) refer to median estimations of subjective probability of obtaining delayed rewards (expressed in percentages and divided by 100) with the AUC computed as areas under the lines that connect these points (lower row). All data are presented for traditional cigarette smokers (Cig), e-cigarette users (eCig), and never smokers (NS). Error bars represent a 95% confidence interval for the mean