Introduction: Individuals with serious mental illness (SMI) smoke cigarettes at a much higher rate than the general population, increasing their risk for medical illnesses and mortality. However, individuals with SMI do not get enough support to quit smoking, partially because of concerns from medical providers that reducing smoking may worsen their symptoms or quality of life.
Methods: Veterans with SMI and nicotine dependence (n = 178) completed a 12-week smoking cessation trial (parent trial dates: 2010-2014) including assessments of smoking status, psychiatric symptoms (Brief Psychiatric Rating Scale), and quality of life (Lehman Quality of Life Interview-Short Version) at up to four time points: baseline, post-treatment, three-month follow-up, and 9-month follow-up. Bayesian multilevel modeling estimated the impact of changes in the self-reported number of cigarettes per day in the past seven days on psychiatric symptoms and quality of life.
Results: Between subjects, each additional pack of cigarettes smoked per day was associated with a 0.83 point higher score (95%CI: 0.03 to 1.7) on a negative symptoms scale ranging from 0 to 35. Within subjects, each one-pack reduction in the number of cigarettes smoked per day was associated with an improvement of 0.32 (95%CI = 0.12 to 0.54) on the health-related quality of life scale, which ranges from 0 to 7 points. There were no other significant between- or within-subjects effects of smoking on psychiatric symptoms or quality of life.
Conclusions: Individuals with SMI and their providers should pursue smoking cessation without fear of worsening psychiatric symptoms or quality of life.
Trial registration: ClinicalTrials.gov NCT0096037.
Keywords: Psychiatric symptoms; Quality of life; Schizophrenia; Self-medication hypothesis; Serious mental illness; Smoking.
Published by Elsevier Ltd.