A pilot study of cognitive remediation in remitted major depressive disorder patients.

Major depressive disorder (MDD) is associated with working memory (WM) impairments. These deficits often persist following remission and are associated with rumination, a recognized risk factor for depression relapse. The efficacy of WM-targeted cognitive remediation as a potential relapse prevention tool has not been investigated. The present pilot study aimed to investigate the feasibility, acceptability, and cognitive benefits of a WM-targeted cognitive remediation program in remitted depression. Twenty-eight MDD participants in remission were recruited. The intervention consisted of twenty-five 30-40-minute training sessions, coupled with weekly coaching, administered over a 5-week period. Before and after the intervention, a battery of objective neuropsychological tests and self-report measures was administered. Key outcomes were WM, inhibition and rumination. Acceptability of the intervention was observed, with 83% showing high motivation, along with WM gains for all completers (n = 18, 64% of recruited participants). The cognitive remediation selectively improved targeted WM functions, as measured by objective tests. This did not translate into self-reported improvements in everyday WM or inhibition. However, all but one completer achieved at least one personal goal related to WM and 44% achieved two or, the maximum possible, three such goals. For remitters whose WM was significantly enhanced after the intervention, the cognitive remediation also decreased dysphoric-mood related rumination. The successful pilot testing of the WM-targeted intervention supports the conduct of a fully powered randomized controlled trial as a relapse prevention approach in remitted MDD.