Research on the Effect and Long-Term Follow-Up of Cognitive-Behavioral Intervention for Adolescent Depressive Symptoms: A Narrative Review

Background: Adolescent depressive symptoms have become a global public health concern, with increasing prevalence and potential long-term impacts on psychological development, academic performance, and social functioning. Cognitive-Behavioral Therapy (CBT) is a well-established psychological intervention approach, but a comprehensive synthesis of its effectiveness, long-term sustainability, and implementation challenges in adolescent populations is needed. Objective: This narrative review aims to systematically summarize the theoretical basis, intervention strategies, short-term and long-term effects, as well as implementation challenges of CBT for adolescent depressive symptoms, providing evidence-based references for clinical practice and future research. Methods: A systematic search was conducted across PubMed, PsycINFO, Cochrane Library, and Embase databases for English-language studies published between 2010 and 2024. Keywords included "adolescent depression", "cognitive behavioral therapy", "depressive symptoms", "long-term follow-up", and "intervention effectiveness". Studies were selected based on relevance to CBT intervention for adolescents (12-18 years) with depressive symptoms or depressive disorder, including randomized controlled trials (RCTs), systematic reviews, and meta-analyses. Results: CBT effectively alleviates adolescent depressive symptoms in the short term (post-treatment effect size Cohen’s d = 0.42-0.68) and maintains significant improvements during long-term follow-up (6 months to 3 years, d = 0.35-0.51). Core intervention strategies including cognitive restructuring, emotion regulation training, and behavioral activation are key to treatment success. However, intervention effects are moderated by individual differences, therapist competence, therapeutic environment, and family support. The recurrence rate of depressive symptoms post-CBT ranges from 15% to 30% within 2 years, associated with factors such as ongoing life stress and insufficient post-treatment support. Conclusions: CBT is an evidence-based intervention for adolescent depressive symptoms, but personalized implementation, optimization of therapeutic contexts, and multi-system support (family, school) are critical to enhancing effectiveness and reducing recurrence. Future research should focus on standardized intervention protocols, predictors of treatment response, and innovative delivery models (e.g., online CBT) to improve accessibility and sustainability.