Introduction As e-cigarette use increases, questions about individual and public health effects remain unanswered (e.g. cessation tool, addiction path). Despite increasing use, few studies have focused on vape shop patrons. This study examined whether vape shop patrons believe their health is affected by the use of e-cigs; more specifically, the aim was to evaluate the association between e-cig use, change in tobacco use, and perception of health. Methods A survey of e-cig users (N=78) was conducted in vape shops. Questions included e-cig and traditional tobacco use, health perceptions, and demographics. Descriptive techniques were used to characterize participants as either those who perceived e-cig use improved their health or those who perceived their health unaffected. Logistic regression assessed the association between change in tobacco use, e-cig use, and perception of health effects. Results Most reported daily e-cig (91%) and current (11.5%) or former (78.2%) combustible cigarette use. Approximately, three-fourths (76.9%) perceived better health; the remainder (23.1%) perceived unaffected health. Change in cigarette use was significantly associated with perceptions that health is better with e-cig use. Participants who decreased cigarette use by 2-3 cartons/month and more than 3 cartons/month were significantly more likely to indicate that e-cig use has improved their health compared to those who decreased tobacco use by 1.5 cartons or fewer per month (OR=4.35, 95% CI: 1.13-16.9; OR=25.67, 95% CI: 2.97-221.7, respectively). Conclusions The majority of e-cig users perceived better health. Our findings suggest that health campaign designers should carefully assess the scientific uncertainty surrounding the use of these devices and consider means to clearly convey this information. Given the lack of scientific agreement on the health effects of e-cigs and the important role that perceptions play in behavior, health campaign designers, health education practitioners, policy makers, and health care providers should err on the side of caution when advising individuals about e-cig use.

Monocytes exhibiting a pro-inflammatory phenotype play a key role in adhesion and development of atherosclerotic plaques. As an alternative to smoking, next-generation tobacco and nicotine products (NGP) are now widely used. However, little is known about their pro-inflammatory effects on monocytes. We investigated cell viability, anti-oxidant and pro-inflammatory gene and protein expression in THP-1 monocytes after exposure to aqueous smoke extracts (AqE) of a heated tobacco product (HTP), an electronic cigarette (e-cig), a conventional cigarette (3R4F) and pure nicotine (nic). Treatment with 3R4F reduced cell viability in a dose-dependent manner, whereas exposure to alternative smoking products showed no difference to control. At the highest non-lethal dose of 3R4F (20%), the following notable mRNA expression changes were observed for 3R4F, HTP, and e-cig respectively, relative to control; HMOX1 (6-fold, < 2-fold, < 2-fold), NQO1 (3.5-fold, < 2-fold, < 2-fold), CCL2 (4-fold, 3.5-fold, 2.5-fold), IL1B (4-fold, 3-fold, < 2-fold), IL8 (5-fold, 2-fold, 2-fold), TNF (2-fold, 2-fold, < 2-fold) and ICAM1 was below the 2-fold threshold for all products. With respect to protein expression, IL1B (3-fold, < 2-fold, < 2-fold) and IL8 (3.5-fold, 2-fold, 2-fold) were elevated over the 2-fold threshold, whereas CCL2, TNF, and ICAM1 were below 2-fold expression for all products. At higher doses, greater inductions were observed with all extracts; however, NGP responses were typically lower than 3R4F. In conclusion, anti-oxidative and pro-inflammatory processes were activated by all products. NGPs overall showed lower responses relative to controls than THP-1 cells exposed to 3R4F AqE.