Factors associated with response and remission from depression at 6-months of treatment in a retrospective cohort treated within an integrated care program

BACKGROUND: Depression causes significant morbidity, which impacts mental health, overall general health outcomes, everyday functioning and quality of life. This study aims to contribute to knowledge in the field through enhanced understanding of factors that influence depression response and remission, with consideration for design of treatment services to optimize depression outcomes within integrated care programs. METHODS: Using routine behavioral health screening and electronic health record data, we identified a retrospective cohort consisting of 615 adult patients receiving depression treatment within an integrated care program. Cohort member Patient Health Questionnaire (PHQ-9) data was analyzed for the 6 months following initiation of treatment. Multinomial regression models were estimated to identify factors associated with depression treatment response (PHQ-9 < 10) and remission (PHQ-9 < 5). RESULTS: At 6 months, 47% of patients demonstrated treatment response and 16% demonstrated remission. Baseline trauma symptoms and suicidal ideation were significantly associated with decreased odds of achieving remission (Odds Ratio (95% CI) [OR] = 0.45 (0.23, 0.88) and OR = 0.49 (0.29, 0.82), respectively). In fully adjusted models, baseline suicidal ideation remained significant (OR = 0.53 (0.31, 0.89)) and some evidence of an association persisted for baseline trauma symptoms (OR = 0.51 (0.25, 1.01)). CONCLUSIONS: After controlling for baseline depression symptoms, the presence of suicidal ideation is associated with reduced likelihood of remission. Increased understanding of factors associated with depression treatment outcomes may be employed to help guide the delivery and design of clinical services. Alongside routine screening for co-morbid anxiety, suicidal ideation and traumatic stress should be assessed and considered when designing depression treatment services.