OBJECTIVE: More than a decade after e-cigarette (e-cig) market launch, limited information are available on their safety after 24 months of use. In 2013, we started the first observational study assessing e-cig long-term effectiveness and safety, directly comparing tobacco smokers and e-cig users. Here we report the results after four years of follow-up.
PATIENTS AND METHODS: Adults (30-75 years) were included if: smokers of ≥1 tobacco cigarette/day (tobacco smokers); users of any type of e-cig inhaling ≥50 puffs weekly (e-cig users); users of both tobacco and e-cig (dual users). Data were collected by phone and/or internet, and carbon monoxide levels tested in 50% of those declaring tobacco abstinence. Main outcomes were: possibly smoking-related diseases (PSRD; validated through hospital discharge data or visit in 62.6% of the sample); 4-year tobacco abstinence; number of tobacco cigarettes/day.
RESULTS: Data were available for 228 e-cig users (all ex-smokers), 471 tobacco smokers, 216 dual users. A PSRD was observed in 73 subjects (8.0%). No differences emerged across groups in PSRD rates, with negligible variations in self-reported health. Of e-cig users, 63.6% remained tobacco abstinent; dual users and tobacco smokers showed non-significantly different rates of tobacco (33.8% vs. 26.8%) and all-product (20.2% vs. 19.4%) cessation, and a similar decrease in cigarettes/day. Almost 40% of the sample switched at least once (tobacco smokers: 17.2%; dual users: 81.9%).
CONCLUSIONS: After four years, a scarce, non-significant harm reduction was observed among e-cig or dual users. Given the long-lasting health effects of tobacco smoking, the benefits of e-cig use may start being detectable at the next follow-up (six years). The complete switch to e-cig may help tobacco quitters remain abstinent, but e-cig use in addition to tobacco did not increase the likelihood of smoking cessation or reduction.Free PDF Download
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To cite this article
M.E. Flacco, M. Ferrante, M. Fiore, C. Marzuillo, C. La Vecchia, M.R. Gualano, G. Liguori, G. Fragassi, T. Carradori, F. Bravi, R. Siliquini, W. Ricciardi, P. Villari, L. Manzoli
Cohort study of electronic cigarette use: safety and effectiveness after 4 years of follow-up
Eur Rev Med Pharmacol Sci
Vol. 23 - N. 1