Sudden gains in depressed cancer patients treated with behavioral activation therapy.

Many patients who receive cognitive-behavioral therapy experience sudden gains that are associated with improved treatment response and decreased risk of relapse. Extending prior research, this study examined sudden gains among depressed cancer patients receiving brief (9-session) behavioral activation therapy. Fifty percent of patients experienced sudden gains of large magnitude (M=11.8 BDI-II points), with sudden gains associated with improved treatment response and maintenance of gains at 3-month follow-up. Relative to those without sudden gains, at pretreatment assessment, cancer patients with sudden gains were more likely to present with less severe depression, less somatic anxiety, fewer coexistent anxiety disorders, as well as less bodily pain, better overall physical functioning, and fewer problems with daily activities as a result of emotional problems. These findings provide increasing support for behavioral activation with a difficult-to-treat population but raise important questions regarding mechanism of change. Clinical implications for treating depressed cancer patients are discussed.