Psychological and psychosocial interventions for people with schizophrenia spectrum disorders and smoking addiction: A systematic review and pairwise meta-analysis

This systematic review and pairwise meta-analysis examined the efficacy of psychological and psychosocial smoking cessation interventions in individuals with schizophrenia spectrum disorders (SSD). Tobacco use is highly prevalent in this population and negatively affects both physical and mental health, potentially interfering with treatment outcomes. A comprehensive search of electronic databases up to January 13, 2025 identified 14 randomized controlled trials (RCTs), of which nine were included in the meta-analysis. Primary outcomes included smoking reduction measured with a) abstinence (number of abstinent participants), b) validated scales and c) cigarettes smoked per day and overall symptoms of schizophrenia. The results showed that interventions demonstrated beneficial effects on smoking-related outcomes. Consistent for all three outcomes on reduction: abstinence (RR = 1.60, 95% CI : 1.07 to 2.38, 9 trials), validated scales ( SMD = -0.30, 95% CI: -0.58 to -0.01, 2 trials) and cigarettes smoked per day ( MD = -3.09, 95% CI : -5.16 to -1.02, 3 trials). Results showed no improvement in overall symptoms for schizophrenia ( SMD = -0.54, 95% CI: -1.43 to 0.35, 3 trials). Tolerability could not be evaluated due to insufficient reporting of adverse events. Overall, psychological and psychosocial interventions appear effective in reducing smoking in individuals with SSD but show limited impact on psychiatric symptoms. The findings are constrained by limited data, highlighting the need for future research using standardized measures, long-term follow-up, quality-of-life outcomes, and improved reporting of adverse effects.