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Smoking Cessation Interventions for Patients with Severe Mental Illnesses: A Review of Clinical Effectiveness and Guidelines

Last updated: August 24, 2017
Project Number: RC0922-000
Product Line: Rapid Response
Research Type: Devices and Systems
Report Type: Summary with Critical Appraisal
Result type: Report


  1. What is the clinical evidence regarding the effectiveness of smoking cessation interventions for patients with severe mental illnesses?
  2. What are the evidence-based guidelines regarding smoking cessation interventions for patients with severe mental illnesses?

Key Message

Nicotine replacement therapy (NRT), varenicline and bupropion were all generally found to improve smoking cessation rates, most commonly measured as 7-day point prevalence abstinence against placebo, among people with severe mental illness. Varenicline and bupropion may be more effective than NRT. The longest follow up duration on treatment was six months, and sustained effects beyond this were unclear, except in one study that did not find an increase in suicide attempts/behaviours after one year.There was no evidence that adverse events occurred more often than in those without mental illness, or that psychiatric symptoms worsened. Nausea and sleep disturbances were common with varenicline. All studies included some form of psychosocial support in addition to the pharmacological intervention, and only one study considered randomizing different dosages for NRT, and did not find a difference. In general, the quality of studies was low and sample sizes small.One guideline was found, which did not favour any treatment, but suggested considering NRT, varenicline or bupropion for patients with severe mental illness, with safety caveats for the latter two that may require closer patient monitoring.