RESUMEN
Background: The success of pharmacotherapies for smoking cessation in real-life remains limited, with a significant number of long-term relapses. Despite first promising results, the duration of the effectiveness of electronic cigarettes is still unknown. Our objective was to assess the duration of the effectiveness of electronic cigarettes on smoking cessation and reduction in daily smokers. Methods: The databases EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov and PUBMED were consulted until March 23, 2022. We selected only randomized controlled trials with daily adult smokers. The intervention was the nicotinic electronic cigarette vs. non-nicotine electronic cigarette or other validated pharmacotherapies (varenicline, bupropion and nicotine replacement therapy). The minimum duration of the intervention was 3 months, with a follow-up of at least 6 months. Two independent reviewers used the PRISMA guidelines. The primary endpoint was smoking cessation at the end of the intervention and follow-up periods confirmed by a reduction in expired CO < 10 ppm. The reduction was defined as at least 50% of the initial consumption or by a decrease of daily mean cigarette consumption at the end of the intervention and follow-up periods. Results: Abstinence at the end of the intervention and follow-up periods was significantly higher in the nicotine electronic cigarette group, compared to nicotine replacement therapy (NRT) [respectively: RR: 1.37 (CI 95%: 1.32-2.93) and RR: 1.49 (CI 95%: 1.14-1.95)] and to the non-nicotine electronic cigarette condition [respectively: RR: 1.97 (CI 95%: 1.18-2.68) and RR: 1.66 (CI 95%: 1.01-2.73)]. With regard to smoking reduction, the electronic cigarette with nicotine is significantly more effective than NRT at the end of the intervention and follow-up periods [respectively RR: 1.48 (CI 95%: 1.04-2.10) and RR: 1.47 (CI 95%: 1.18-1.82)] and non-nicotine electronic cigarette in the long term [RR: 1.31 (CI 95%: 1.02-1.68)]. Conclusions: This meta-analysis shows the duration of the effectiveness of the nicotine electronic cigarette vs. non-nicotine electronic cigarette and NRT on smoking cessation and reduction. There are still uncertainties about the risks of its long-term use and its potential role as a gateway into smoking, particularly among young people.
RESUMEN
AIM: To assess the efficacy of drugs directly acting on alpha- and beta-adrenergic receptors in the treatment of patients suffering from tobacco or alcohol use disorder. METHODS: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, studies were identified through PUBMED, EMBASE, the Cochrane Central Register of Controlled Trials and clinicaltrial.gov. We selected only randomized controlled trials with adult patients with tobacco or alcohol use disorders according to DSM-5 criteria. Interventions included any molecule having a direct pharmacological action on alpha- or beta-adrenergic receptors (agonist or antagonist). Comparators were placebo or other validated pharmacotherapies. The duration of the intervention was a minimum of 1 month, with 3 months of follow-up. Measurements included smoking cessation for tobacco; for alcohol, we selected abstinence, alcohol consumption (drinks per day or week) and heavy drinking days (HDD). Ten studies with tobacco and six with alcohol use disorder were included in the qualitative synthesis and fifteen studies in the quantitative analysis. RESULTS: We found that clonidine, an alpha-2 agonist, significantly increased smoking abstinence [relative risk = 1.39 with a 95% confidence interval (CI) = 1.04, 1.84]. Beta-blockers had no significant effect on smoking abstinence. The alpha-1 antagonists prazosin and doxazosin decreased alcohol consumption [SMD = -0.32 (-0.56, -0.07)] but had no effect on abstinence or HDD. CONCLUSIONS: The noradrenaline system may represent a promising mechanism to target in tobacco and alcohol use disorders.