Sustained Smoking Abstinence Following Psychiatric Hospitalization is Associated with Substantial Decreases in Depression and Anxiety Symptoms

INTRODUCTION: Individuals with psychiatric disorders experience substantial tobacco-related morbidity and mortality. Concerns persist that smoking cessation may exacerbate depression and anxiety, potentially limiting treatment efforts in psychiatric settings. This study examined whether sustained smoking abstinence following psychiatric hospitalization is associated with changes in depressive and anxiety symptoms. METHODS: This secondary analysis used data from the Helping HAND 3 RCT of a smoking cessation intervention among psychiatric inpatients. Participants (N=224) with elevated baseline depression and/or anxiety symptoms on the PROMIS Depression and Anxiety Short Forms 8a were assessed at 1-, 3-, and 6-months post-discharge. Self-reported continuous abstinence (vs. continuous smoking) was examined as a predictor of depressive and anxiety symptoms using linear mixed models. RESULTS: Continuous abstinence was associated with significant reductions in depressive (β = -3.88, 95% CI: -7.29, -0.47, p = .026) and anxiety symptoms (β = -5.06, 95% CI: -8.11, -2.02, p = .001) across follow-up. Significant abstinence-by-time interactions indicated that longer durations of abstinence were associated with greater symptom improvements. At 6 months, abstinence, compared to continued smoking, was associated with large reductions in depression (Cohen's d = 1.10) and anxiety (Cohen's d = 1.21). Participants who remained abstinent improved from markedly elevated baseline symptom levels to near population norms. CONCLUSIONS: Sustained smoking abstinence following psychiatric hospitalization is associated with substantial improvements in depression and anxiety. These findings challenge concerns that tobacco cessation worsens psychiatric symptoms and suggest that integrating evidence-based cessation interventions into routine psychiatric care could improve overall treatment outcomes without compromising symptom stability.