Cohort study of electronic cigarette use: effectiveness and safety at 24 months.

To evaluate the safety and effectiveness of e-cigarettes, by comparing users of only e-cigarettes, smokers of only tobacco cigarettes and dual users. Prospective cohort study. We update previous 12-month findings and report the results of the 24-month follow-up. Direct contact and questionnaires by phone or via internet. Adults (30-75 years) were classified as: (1) tobacco smokers, if they smoked ≥1 tobacco cigarette/day, (2) e-cigarette users, if they inhaled ≥50 puffs/week of any type of e-cigarette and (3) dual users, if they smoked tobacco cigarettes and also used e-cigarettes. Carbon monoxide levels were tested in 50% of those declaring tobacco smoking abstinence. Hospital discharge data were used to validate possibly related serious adverse events in 46.0% of the sample. Sustained abstinence from tobacco cigarettes and/or e-cigarettes after 24 months, the difference in the number of tobacco cigarettes smoked daily between baseline and 24 months, possibly related serious adverse events. Data at 24 months were available for 229 e-cigarette users, 480 tobacco smokers and 223 dual users (overall response rate 68.8%). Of the e-cigarette users, 61.1% remained abstinent from tobacco (while 23.1% and 26.0% of tobacco-only smokers and dual users achieved tobacco abstinence). The rate (18.8%) of stopping use of either product (tobacco and/or e-cigarettes) was not higher for e-cigarette users compared with tobacco smokers or dual users. Self-rated health and adverse events were similar between all groups. Among those continuing to smoke, there were no differences in the proportion of participants reducing tobacco cigarette consumption by 50% or more, the average daily number of cigarettes and the average self-rated health by baseline group. Most dual users at baseline abandoned e-cigarettes and continued to smoke tobacco. Those who continued dual using or converted from tobacco smoking to dual use during follow-up experienced significant improvements in the 3 outcomes compared with those who continued or switched to only smoking tobacco (p<0.001). E-cigarette use alone might support tobacco quitters remaining abstinent from smoking. However, dual use did not improve the likelihood of quitting tobacco or e-cigarette use, but may be helpful to reduce tobacco consumption. Adverse event data were scarce and must be considered preliminary. NCT01785537.

Manzoli L ，Flacco ME ，Ferrante M ，La Vecchia C ，Siliquini R ，Ricciardi W ，Marzuillo C ，Villari P ，Fiore M ，ISLESE Working Group ... -  《-》

Electronic Cigarettes Efficacy and Safety at 12 Months: Cohort Study.

Manzoli L ，Flacco ME ，Fiore M ，La Vecchia C ，Marzuillo C ，Gualano MR ，Liguori G ，Cicolini G ，Capasso L ，D'Amario C ，Boccia S ，Siliquini R ，Ricciardi W ，Villari P ... -  《PLoS One》

Cohort study of electronic cigarette use: safety and effectiveness after 4 years of follow-up.

Flacco ME ，Ferrante M ，Fiore M ，Marzuillo C ，La Vecchia C ，Gualano MR ，Liguori G ，Fragassi G ，Carradori T ，Bravi F ，Siliquini R ，Ricciardi W ，Villari P ，Manzoli L ... -  《-》

Reductions in biomarkers of exposure, impacts on smoking urge and assessment of product use and tolerability in adult smokers following partial or complete substitution of cigarettes with electronic cigarettes.

D'Ruiz CD ，Graff DW ，Robinson E 《BMC PUBLIC HEALTH》

A longitudinal study of electronic cigarette users.

To assess behavior change over 12 months in users of e-cigarettes ("vapers"). Longitudinal Internet survey, 2011 to 2013. Participants were enrolled on websites dedicated to e-cigarettes and smoking cessation. We assessed use of e-cigarettes and tobacco among the same cohort at baseline, after one month (n=477) and one year (n=367). Most participants (72%) were former smokers, and 76% were using e-cigarettes daily. At baseline, current users had been using e-cigarettes for 3 months, took 150 puffs/day on their e-cigarette and used refill liquids containing 16 mg/ml of nicotine, on average. Almost all the daily vapers at baseline were still vaping daily after one month (98%) and one year (89%). Of those who had been vaping daily for less than one month at baseline, 93% were still vaping daily after one month, and 81% after one year. In daily vapers, the number of puffs/day on e-cigarettes remained unchanged between baseline and one year. Among former smokers who were vaping daily at baseline, 6% had relapsed to smoking after one month and also 6% after one year. Among dual users (smokers who were vaping daily at baseline), 22% had stopped smoking after one month and 46% after one year. In dual users who were still smoking at follow-up, cigarette consumption decreased by 5.3 cig/day after one month (from 11.3 to 6.0 cig./day, p=0.006), but remained unchanged between baseline and 1-year follow-up. E-cigarettes may contribute to relapse prevention in former smokers and smoking cessation in current smokers.

Etter JF ，Bullen C 《-》