Cognitive remediation (CR) improves cognitive function in patients with bipolar disorder (BD), according to the results of a randomized double-blind controlled trial published in the Journal of Clinical Psychiatry.
Kathryn E. Lewandowski, PhD, of the Schizophrenia and Bipolar Disorder Program, McLean Hospital, Belmont, Massachusetts, and colleagues found significant, durable cognitive change with CR compared with an active, dose-matched computer control in patients with BPD.
In the study, 75 patients with a DSM-IV diagnosis of BD with psychosis were randomly assigned to a 70-hour computerized CR program or a dose-matched computer control. Cognition was the primary outcome and clinical and community functioning were secondary outcomes; all outcomes were assessed at baseline; treatment midpoint; post-treatment; and at follow-up, after 6 months of no study contact.
The investigators found medium to large effects of CR at post-treatment on processing speed (d =0.42), visual learning and memory (d =0.92), and the composite (d =0.80). At 6-month follow-up, they noted superiority of CR over the control for processing speed (d =0.65) and composite (d =0.83). CR was not associated with change in community functioning.
Limitations of the study included a high non-completion rate in both groups that reduced the power to detect group effects. The high attrition rates suggest that the intervention may not be well tolerated by some patients. Furthermore, baseline cognitive scores and premorbid IQ were higher than expected.
The researchers noted that the failure to find a transfer of gains to community functioning is in keeping with studies of CR in patients with schizophrenia. They suggest that inclusion of supportive elements such as rehabilitation may help to drive translation of cognitive improvements to broad functional measures.
The investigators argue that the findings of significant, durable cognitive change against an active, dose-matched computer control support the extension of this intervention to patients with BD to address serious and disabling cognitive symptoms. Furthermore, they call for the implementation of web-based CR to increase access and affordability to more patients.
Lewandowski KE, Sperry SH, Cohen BM, et al. Treatment to enhance cognition in bipolar disorder (TREC-BD): efficacy of a randomized controlled trial of cognitive remediation versus active control [published online October 17, 2017]. J Clin Psychiatry. doi:10.4008/JCP.17m11476