Effectiveness of Psychological Interventions for Smoking Cessation Targeting Diabetes Mellitus: A Systematic Review

INTRODUCTION: Tobacco cessation is a public health priority. However, long-term outcomes remain limited, partly due to insufficient adaptation of interventions to chronic conditions, such as diabetes mellitus (DM), a leading cause of chronic disability worldwide. Evidence regarding the clinical impact of smoking cessation treatments in people with DM remains inconsistent. The objective of this study was to examine the effectiveness of psychological smoking cessation interventions for individuals with type 1 and type 2 DM. METHODS: A search for scientific studies was conducted in four databases (PubMed, Web of Science, SCOPUS, and PsycINFO), resulting in the selection of 12 studies following PRISMA guidelines (PROSPERO, ID: CRD42024531545). RESULTS: Overall, 83.3% of the interventions incorporated diabetes-adapted components. Programs frequently achieved short-term reductions in cigarette consumption, although complete long-term abstinence was less frequent. Only a minority of studies demonstrated statistically significant higher abstinence rates in the intervention groups than in the control groups, ranging from 31.3% to 70.6% at 6 months and 20.0% to 38.8% at 12 months. The most favorable outcomes occurred in group-based, multicomponent programs for type 2 DM combining diabetes-specific psychoeducation, motivational strategies, and optional pharmacotherapy. CONCLUSIONS: Due to a moderate-to-high risk of bias across studies, evidence regarding the effectiveness of psychological smoking cessation interventions for individuals with DM remains limited. Further research is needed to identify factors that influence smoking cessation outcomes in patients with DM. The integration of evidence-based programs and interventions tailored to diabetes-related needs, associated comorbidities, and gender-specific factors are essential to address these challenges.