Background: In 2001, the Canadian Psychiatric Association and the Canadian Network for Mood and Anxiety Treatments (CANMAT) partnered to produce evidence-based clinical guidelines for the treatment of depressive disorders. A revision of these guidelines was undertaken by CANMAT in 2008-2009 to reflect advances in the field. This article, one of five in the series, reviews new studies of psychotherapy in the acute and maintenance phase of MDD, including computer-based and telephone-delivered psychotherapy.
Methods: The CANMAT guidelines are based on a question-answer format to enhance accessibility to clinicians. Evidence-based responses are based on updated systematic reviews of the literature and recommendations are graded according to the Level of Evidence, using pre-defined criteria. Lines of Treatment are identified based on criteria that included evidence and expert clinical support.
Results: Cognitive-Behavioural Therapy (CBT) and Interpersonal Therapy (IPT) continue to have the most evidence for efficacy, both in acute and maintenance phases of MDD, and have been studied in combination with antidepressants. CBT is well studied in conjunction with computer-delivered methods and bibliotherapy. Behavioural Activation and Cognitive-Behavioural Analysis System of Psychotherapy have significant evidence, but need replication. Newer psychotherapies including Acceptance and Commitment Therapy, Motivational Interviewing, and Mindfulness-Based Cognitive Therapy do not yet have significant evidence as acute treatments; nor does psychodynamic therapy.
Limitations: Although many forms of psychotherapy have been studied, relatively few types have been evaluated for MDD in randomized controlled trials. Evidence about the combination of different types of psychotherapy and antidepressant medication is also limited despite widespread use of these therapies concomitantly.
Conclusions: CBT and IPT are the only first-line treatment recommendations for acute MDD and remain highly recommended for maintenance. Both computer-based and telephone-delivered psychotherapy--primarily studied with CBT and IPT--are useful second-line recommendations. Where feasible, combined antidepressant and CBT or IPT are recommended as first-line treatments for acute MDD.