Outcomes of Acceptance and Commitment Therapy for depression and predictors of treatment response in Veterans Health Administration patients

• Published in: Journal of affective disorders Vol. 323; pp. 826 - 833
• Main Authors: Grau, Peter P., Sripada, Rebecca K., Ganoczy, Dara, Weinstein, Jonathan H., Pfeiffer, Paul N.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.02.2023
• Subjects: Acceptance and Commitment Therapy; Depression; Depression - therapy; Humans; Psychiatric/Mental Health; Psychotherapy; Stress Disorders, Post-Traumatic - complications; Stress Disorders, Post-Traumatic - therapy; Treatment Outcome; Veterans; Veterans - psychology; Veterans Health; Acceptance and Commitment Therapy; Psychotherapy; Depression; Veterans
• ISSN: 0165-0327; 1573-2517; 1573-2517
• DOI: 10.1016/j.jad.2022.12.025

Acceptance and Commitment Therapy for depression (ACT-D) is a promising depression treatment which has not been evaluated on a large scale within VA. This study aimed to evaluate ACT-D's effectiveness in a national, treatment-seeking sample of Veterans. The sample comprised 831 Veterans who received a primary depression diagnosis and received at least two sessions of ACT-D during fiscal years 2015–2020. We used GLM to measure predictors of symptom change, treatment response (50 % reduction in PHQ-9 and AAQ-II scores), subthreshold depression symptoms (PHQ-9 < 10; AAQ-II < 27), and treatment completion. Veterans experienced an average reduction of 3.39 points on the PHQ-9 (Cohen's d = 0.56) and 3.76 points on the AAQ-II (Cohen's d = 0.43). On the PHQ-9, 40 % achieved subthreshold depression symptoms. On the AAQ-II, 36 % of Veterans achieved subthreshold psychological inflexibility scores. Service-connected disability rating for depression and higher levels of medical comorbidity were both related to lower levels of overall depression symptom change and treatment response. Substance use disorder and bipolar/psychosis diagnoses were associated with greater reductions in psychological inflexibility. This is an observational study without a control group, so we were unable to compare the effectiveness of ACT-D to other usual care for depression. We were also unable to assess variables that can influence treatment success, such as therapist fidelity and patient engagement. ACT-D achieved similar improvements in depression as reported in controlled trials. Adaptations to ACT-D may be needed to improve outcomes for Veterans with depression and comorbid PTSD. •Veterans experienced medium effect size decreases in depression over the course of ACT-D•We found similar effects for ACT-D as have been found in other studies of cognitive-behavioral therapies for depression.•Veterans with depression and comorbid PTSD experienced less change in depression symptoms.•ACT approaches might be helpful to incorporate for individuals for substance use disorder and bipolar/psychosis diagnoses