Effectiveness of Cognitive Behavioral Therapy in Reducing Suicidal Ideation and Influential Factors in Patients With Major Depressive Disorder: A Systematic Review and Meta-Analysis

To evaluate the effectiveness of cognitive behavioral therapy (CBT) interventions in reducing suicidal ideation among patients with depression, and to identify factors that moderate treatment outcomes, a systematic review and meta-analysis was conducted searching seven major biomedical databases (CNKI, China Wanfang Database, Cochrane Library, PubMed, Web of Science, Embase, and Sinomed) from inception to November 8, 2023. Randomized controlled trials examining CBT interventions for suicidal ideation in depressed patients were included. Fourteen studies (1256 patients) met inclusion criteria. CBT demonstrated a moderate effect in reducing suicidal ideation compared to control conditions (Hedges' g = −0.47 (95% CI [−0.73, −0.22]), p < 0.01). Significant moderators included intervention mode (Q = 8.33, p < 0.05), suicidal ideation measure (Q = 17.98, p < 0.001), intervention duration (Q = 9.55, p < 0.05), and CBT follow-up interval (Q = 6.66, p < 0.05). Age, intervention cycles, frequency, and intervention form did not significantly moderate outcomes. No publication bias was detected, and the overall quality of evidence was moderate. CBT is effective in reducing suicidal ideation among patients with depression. Factors associated with greater effectiveness include combining CBT with drug, targeting older adults, using specific suicidal ideation measures (e.g., C-SSRS, SIOSS), interventions lasting 0–12 weeks with more than once a week, more than an hour per session, and short-term follow-up. Group therapy formats may also enhance outcomes. Future randomized trials should further examine these factors and assess impacts on suicidal behaviors in addition to ideation.