Investigating the reciprocal temporal relationships between tobacco consumption and psychological disorders for youth: an international review

ObjectiveTo investigate reciprocal temporal relationships between tobacco consumption and psychological disorders for youth.Design: ReviewData sourcesFive databases (PubMed, Embase, Scopus, CINAHL and PsycINFO) on 26 September 2019 and updated on 11 May 2021, indexing tobacco, mental illness and longitudinal.Study selection: Methods used consensus and multiple reviewers.InterventionsCohort studies (n=49) examining tobacco and selected psychological disorders (depression, anxiety, bipolar, psychosis, borderline personality disorder) among youth, and systematic reviews (n=4) of these relationships met inclusion criteria.Primary and secondary outcome measuresEffect of tobacco on psychological disorders and effect of psychological disorders on tobacco.Data extraction and synthesisIndependent extraction by the first author and checked by final author. Joanna Briggs Institute Critical Appraisal Tools were used for all studies.Included studies had moderate-to-high appraisal scores. We synthesised findings using vote counting for effect direction and descriptive data.ResultsFifty-three studies were included in the review. Thirteen of 15 studies showed a positive effect direction of tobacco on depression (p