Integrating trauma-informed principles into collaborative care for depression in primary care.

Depression remains one of the leading causes of disability worldwide despite the availability of effective pharmacological and psychological treatments. Collaborative care has consistently improved depression outcomes through coordinated, multidisciplinary, and measurement-based approaches, particularly in primary care. However, substantial heterogeneity in treatment response persists, especially among adults with histories of childhood maltreatment, who frequently present with earlier illness onset, greater symptom severity, increased psychiatric comorbidity, poorer treatment response, and a more chronic clinical course. Although collaborative care is effective, assessment of childhood maltreatment and trauma-informed developmental formulation are not consistently integrated into routine depression management within these models. In this Perspective, we propose Trauma-Informed Collaborative Care (TICC) as a conceptual framework for integrating trauma-informed and developmental principles into collaborative care for depression. Rather than replacing existing evidence-based interventions, TICC seeks to strengthen collaborative care by incorporating trauma-informed assessment, developmental case formulation, trusting therapeutic relationships, interdisciplinary supervision, recognition of patients' strengths and resilience, and organizational practices that promote safety, trustworthiness, collaboration, and empowerment. We review complementary bodies of evidence that provide the rationale for this approach, summarize findings from a recent cluster randomized controlled trial conducted in Chile, and discuss key implementation challenges and future research priorities. Taken together, these distinct bodies of evidence provide a rationale for integrating trauma-informed principles into collaborative care, particularly for patients with histories of childhood maltreatment and greater clinical complexity, while the incremental clinical benefit of this integration within the proposed TICC framework remains to be established.