This Cochrane living systematic review assessed whether electronic cigarettes (EC)—handheld devices that generate an aerosol by heating a liquid—help people who smoke tobacco to achieve long-term abstinence, and whether EC are safe and tolerable for this purpose. The review compared EC to non-nicotine EC, other cessation treatments, and no treatment.
The authors searched CENTRAL, MEDLINE, Embase, and PsycINFO through 1 January 2026, performed reference checking, and contacted study authors. Included studies were randomized controlled trials (RCTs) that allocated people who smoked to an EC or a control condition and measured at least one eligible outcome related to cessation or safety.
Critical outcomes prespecified were abstinence from smoking after at least six months, adverse events (AEs), and serious adverse events (SAEs). Important outcomes included biomarkers, measurements of toxicants/carcinogens, long-term study product use, and long-term patterns of EC and combustible cigarette use. Risk of bias for individual studies was assessed using the RoB 1 tool and overall certainty of evidence was rated using GRADE.
The review included 80 completed RCTs, representing 29,861 participants. Nine RCTs were new to this update. Of the included studies, 12 were judged at low risk of bias, 41 at high risk, and the remainder at unclear risk overall.
Pooled analyses showed that nicotine EC resulted in increased quit rates compared with nicotine replacement therapy (NRT). This finding was reported as high-certainty evidence with a pooled risk ratio (RR) of 1.61 (95% confidence interval [CI] 1.23 to 2.12) across 11 studies including 4,114 participants. Heterogeneity was moderate (I² = 55%).
In absolute terms, the pooled effect was presented as approximately four additional quitters per 100 people (95% CI 1 to 7 more) when using nicotine EC compared with NRT, based on the data in the abstract.
The proportion of participants experiencing adverse events (AEs) may be similar between nicotine EC and NRT. The pooled estimate reported in the abstract was RR 0.95 (95% CI 0.72 to 1.24) from eight studies with 3,107 participants. The authors rated this as low-certainty evidence, noting limitations from imprecision and inconsistency and observed substantial heterogeneity (I² = 72%).
The abstract states that the proportion experiencing serious adverse events (SAEs) is probably similar between groups (moderate-certainty evidence). The source abstract is truncated and does not include further numerical details on SAEs in the excerpt provided; those additional figures were not reported in the text available here.
The review identified biomarkers, toxicants/carcinogens, long-term study product use, and patterns of EC and combustible cigarette use as important outcomes. The abstract does not provide detailed numerical results or summaries for these outcomes in the excerpt supplied, and those specific results were not reported in the source text available for this summary.
Standard Cochrane methods were followed for study screening and data extraction. Where appropriate, the authors pooled data using random-effects models. For dichotomous outcomes they calculated risk ratios (RRs) with 95% CIs; for SAEs they calculated risk differences (RD) with 95% CIs; and for continuous outcomes they used mean differences (MD) or standardized mean differences (SMD) with 95% CIs. GRADE was used to assess certainty of evidence for outcomes.
Risk of bias across included trials was mixed, with many studies at high or unclear risk. Several outcome syntheses showed heterogeneity and imprecision. The abstract text available from the source is truncated in places (for example, additional numerical details on SAEs and results for biomarkers or long-term use were not reported in the excerpt), so further specifics beyond those presented in the abstract could not be summarized here.
Based on the RCT evidence reported in the abstract from this Cochrane living review, nicotine electronic cigarettes increase smoking cessation rates compared with nicotine replacement therapy (high-certainty evidence) and may result in similar rates of adverse events (low-certainty evidence) with SAEs probably similar (moderate-certainty evidence). Details for some outcomes (biomarkers, toxicants/carcinogens, detailed SAE counts, and long-term usage patterns) were not provided in the abstract excerpt and are not reported here.
(Reference: Lindson N et al. Cochrane Database Syst Rev. 2026 Aug 26:CD010216. DOI: 10.1002/14651858.CD010216.pub11; PubMed PMID: 42642048.)