title: Reducing smoking reduces suicidality among individuals with psychosis: Complementary outcomes from a Healthy Lifestyles intervention study.
abstract: This study sought to explore the impact of smoking reduction on suicidality (suicide ideation and behaviour) among people with a psychotic disorder (n=235) who participated in a randomized trial of a healthy lifestyle intervention trial. Suicidality, measured by item -4 of the Brief Psychiatric Rating Scale (BPRS) was the main variable of interest. Measures were collected by research assistants blind to treatment allocation at baseline, at 15 weeks (mid-intervention) and 12 months after baseline. Mediation analysis, adjusted for confounders, was used to determine the relationship between smoking reduction and suicidality and to explore whether this was mediated through depression. At 12 months, smoking reduction was found to be significantly associated with suicidality change; an association was also seen between smoking reduction and depression and depression and suicidality. After adjusting for depression, the association between smoking reduction and suicidality was attenuated but remained statistically significant; the proportion of the total effect that was mediated through depression was 30%. There was no significant association between suicidality and treatment group (vs. controls) over time. Our study suggests that smoking interventions may have benefits over and above those for improved physical health, by reducing suicidal ideation in people with psychosis.
authors.affiliation: Hunter New England Mental Health Service, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia. Electronic address: anoopshank2000@gmail.com.
authors.forename: Anoop
authors.initials: A
authors.lastname: Sankaranarayanan
authors.affiliation: School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Clark
authors.affiliation: School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia.
authors.forename: Amanda
authors.initials: A
authors.lastname: Baker
authors.affiliation: Public Health Program, Hunter Medical Research Institute (HMRI), Newcastle, NSW, Australia.
authors.forename: Kerrin
authors.initials: K
authors.lastname: Palazzi
authors.affiliation: Hunter New England Mental Health Service, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan, NSW, Australia; Centre for Translational Neuroscience and Mental Health, University of Newcastle, Australia.
authors.forename: Terry J
authors.initials: TJ
authors.lastname: Lewin
authors.affiliation: School of Public Health and Community Medicine, University of New South Wales, Sydney, Australia.
authors.forename: Robyn
authors.initials: R
authors.lastname: Richmond
authors.affiliation: Centre for Translational Neuroscience and Mental Health, University of Newcastle, Australia; NHMRC Centre for Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Australia.
authors.forename: Frances J
authors.initials: FJ
authors.lastname: Kay-Lambkin
authors.affiliation: Monash Alfred Psychiatry Research Centre, Central Clinical School, Monash University, Victoria, Australia; Alfred Hospital, 55 Commercial Road, Prahran, Melbourne, Victoria, Australia.
authors.forename: Sacha
authors.initials: S
authors.lastname: Filia
authors.affiliation: St. Vincent's Hospital, PO Box 2900, Fitzroy, Victoria, Australia; The University of Melbourne, Parkville, Melbourne, Victoria, Australia; Faculty of Health Sciences, Australian Catholic University, 1100 Nudgee Road, Banyo, Queensland, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Castle
authors.affiliation: Division of Addiction Psychiatry, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, USA.
authors.forename: Jill M
authors.initials: JM
authors.lastname: Williams
mesh_terms: D000328:Adult; D003863:Depression / Q000523:psychology*; D005260:Female; D000070497:Healthy Lifestyle; D006801:Humans; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000523:psychology*; D000074264:Smoking Reduction / Q000523:psychology*; D059020:Suicidal Ideation; D013405:Suicide / Q000523:psychology*
keywords: Psychosis; Schizophrenia; Smoking; Suicidality; Suicide; Suicide risk