The efficacy of smoking cessation interventions in low- and middle-income countries: a systematic review and meta-analysis

AIMS: To summarize evidence for the efficacy of smoking cessation interventions in low- and middle-income countries (LMICs). DESIGN: Systematic review and meta-analysis of randomized controlled trials. SETTING: LMICs as defined by the World Bank. PARTICIPANTS: Adult current cigarette smokers residing in LMICs. INTERVENTIONS: Behavioral and/or pharmacotherapy smoking cessation interventions. MEASUREMENTS: PubMed MEDLINE, EMBASE (embase.com), Cochrane Central Register of Controlled Trials (Wiley), PsycINFO (Ebsco), SciELO, WHO Global Index Medicus and Scopus were searched from inception to 4 April 2018. Only studies with at least 6 months of follow-up were included. We used the most rigorous assessment of abstinence reported by each study. Effect sizes were computed from abstracted data. Where possible, a meta-analysis was performed using Mantel-Haenzel random-effect models reporting odds ratios (OR) and 95% confidence intervals (CI). FINDINGS: Twenty-four randomized controlled trials were included. Six investigated the efficacy of pharmacological agents. Four trials that compared nicotine replacement therapy (NRT) to placebo found NRT improved cessation rates (n : NRT 546, control 684, OR = 1.76, 95% CI = 1.30-2.77, P < 0.001, I2 = 13%). Eight trials found that behavioral counseling was more effective than minimal interventions (e.g. brief advice); n : Counseling 2941, control 2794, OR = 6.87, 95% CI = 4.18-11.29, P < 0.001, I2 = 67%). There was also evidence of the benefit of brief advice over usual care (n : Brief advice 373, control 355, OR = 2.46, 95% CI = 1.56-3.88, P < 0.001, I2 = 0%). CONCLUSION: Nicotine replacement therapy, behavioral counseling and brief advice appear to be effective in aiding smoking cessation in low- and middle-income countries. There is limited rigorous research on other smoking cessation interventions in these regions.