An exploratory, randomised, crossover study to investigate the effect of nicotine on cognitive function in healthy adult smokers who use an electronic cigarette, after a period of smoking abstinence: study protocol

Harry Jacob Green, Olivia Katherine O'Shea, Helen Louise Philpott, Nik Newland

Abstract

Background: Despite the known harmful effects of cigarette smoking, many individuals continue to smoke. Published scientific evidence suggests that smoking can influence various physiological and psychological functions (including effects on cognitive function, body weight and emotion). For some smokers, the loss of such effects have been cited as barriers to cigarette smoking cessation and the deficits in such effects may contribute to resumption of smoking post quitting. Whilst not positioned as cigarette cessation devices, the effect of e-cigarettes (and other potentially reduced risk alternatives to cigarette smoking) on such functions has not been widely researched. Such information would provide support for the proposition that smokers seeking alternatives may find e-cigarettes a satisfactory substitute for conventional cigarettes.

Methods: This randomised, partially blinded, crossover study will test the hypothesis that acute nicotine delivery via an e-cigarette can influence cognitive parameters including sustained attention, episodic memory, working memory and executive function to the same extent as a combustible cigarette after a period of nicotine abstinence in current smokers. To determine participants’ cognitive ability, the study will utilise the Cambridge Neuropsychological Test Automated Battery (CANTAB) Connect Profile Software (CANTAB® www.cantab.com). Up to 40 current smokers will be recruited into the study.

Conclusions: The data from this trial will be a valuable addition to the growing body of literature assessing the impact of RRPs for existing smokers.

Trial registration: This study is registered with the ISRCTN registry, number ISRCTN35376793.

Keywords

Nicotine, E-cigarette, Cognitive function, Smoking cessation, Tobacco harm-reduction

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