The prevalence of tobacco smoking in schizophrenia patients is high and linked to poor clinical outcomes such as relapses, non-remission, and poor medication adherence. Although some studies suggest cognitive benefits of smoking in schizophrenia, recent longitudinal findings challenge the self-medication hypothesis. However, evidence remains inconclusive, especially regarding short-term (i.e., within 6 months of follow-up) changes in smoking and clinical outcomes in first-episode psychosis (FEP) patients in remission. This study investigated the association between changes in tobacco smoking, psychotic symptoms, and cognitive functioning in FEP patients in remission for 3-6 months (N = 237). Additionally, it explored the role of potential confounders. Data were drawn from the HAMLETT study, a randomized controlled trial on antipsychotic discontinuation. Longitudinal analyses were performed with linear mixed-effects models, adjusting for gender and age, with exploratory models adjusting for additional covariates (e.g., education, occupation, antipsychotic medication use, and cannabis use). Smoking rates remained stable over follow-up. Notably, smoking status was not associated with psychotic symptoms or neurocognitive functioning. Yet, a higher number of smoked cigarettes per day was linked to poorer symbol coding performance and elevated positive symptoms, but this association was lost after covariate adjustment in exploratory analyses. These findings further challenge the self-medication hypothesis and suggest that the adverse effects of smoking may not manifest in the short term in remitted FEP patients.
Keywords: Tobacco, symptoms, cognition, first-episode psychosis, remission