Identifying the barriers to implementing cognitive remediation therapy for mood disorders

To the Editor

Douglas et al. (2019) offer a three-pronged approach to improving the use of cognitive remediation (CR) in clinical settings for mood disorders. Education, first, of the types of cognitive deficits, and, second, on what CR entails, both, will certainly be useful exercises. Their third suggestion, changing the name from CR to cognitive enhancement therapy (CET), is a nuance that will probably not result in any benefit to the field; in the most part, this is because the names or labels are often used interchangeably anyway, alongside other such names as brain training, cognitive training and cognitive rehabilitation. The ingredients of their proposed CET are typical of most modern CR approaches for serious mental health disorders (i.e. psychoeducation, the CR itself and transfer of CR skills to everyday life); thus, a new paradigm was not described.

There certainly are barriers to implementing CR for mood disorders. Douglas et al. (2019) did not touch on a number of important issues that will be highlighted here. Identifying the profile and severity of cognitive impairments would appear to be critical to using CR effectively. This has been relatively straightforward when considering schizophrenia, as the large majority of patients with a diagnosis of schizophrenia demonstrate global cognitive impairments, implying a need for CR. In contrast, despite at least 30 years of focussed research in bipolar disorder and major depressive disorder, we are only just beginning to understand their cognitive profiles. For example, recent data have illustrated evidence of cognitive heterogeneity in bipolar disorder, with typically three clusters of performance recognised: intact, moderate impairments and significant impairments (i.e. for bipolar disorder – 50%, 32% and 18%, respectively; with data in schizophrenia demonstrating 13%, 47% and 40%, respectively: Van Rheenen et al., 2016). Such research suggests that only 50% of bipolar patients might benefit from CR and that comprehensive cognitive assessment prior to initiating CR is vital.

Relatedly, given the paucity of CR studies in mood disorders, we have not yet begun to understand the prognostic value of demographic, clinical, cognitive, treatment and other variables of interest, for example, intrinsic motivation (Bryce et al., 2018a). A recent systematic review in schizophrenia (Reser et al., 2019) showed baseline ‘learning potential’ (i.e. whether a person was able to learn on a simple list learning task during their initial assessment) was the best predictor in the literature of whether an individual would benefit from CR. While steps are being taken towards better understanding the source of differences in response to cognitive remediation therapy (CRT) broadly in severe mental illness, we have not yet arrived at the place where we can match an individual with a mood disorder to the CR programmes they are most likely to receive benefit from. Furthermore, cultural and country-specific features have not yet been investigated.

Most clinicians, independent of discipline background, recognise the importance of cognition for functional recovery. Most countries, however, even wealthy industrialised nations, have a paucity of (a) neuropsychologists necessary to complete appropriate neuropsychological or cognitive assessments to identify an individuals’ cognitive profile, and (b) neuropsychologists or approved cognitive trainers to implement the CR programmes within rehabilitation services. Furthermore, when services are available, they are at capacity with long waiting lists, or in the case of Australia, the number of service-funded CR sessions is considerably below that of the recommended average dose for CR (i.e. 20–40 hours); with private CR unaffordable for most mood disorder patients.

Recent technological advances in smartphones, and related devices, have not yet been capitalised upon in CR research and implementation. Such devices make it easier for individuals to have access to relevant CR software packages in their own time. Empirical research is needed to examine the efficacy of self-directed CR, versus standard face-to-face CR training, versus perhaps a blended approach with a mix of face-to-face sessions with self-directed homework. The later suggestion here would clearly allow patients to benefit from both expert cognitive trainers as well as giving them flexibility to engage with additional CR when time permits.

Developments in CR interventions need to consider the patient perspective. There have been a handful of recent studies which have completed qualitative interviews with individuals after they have finished their CR training (i.e. Bryce et al., 2018b). Patients commented that they found CR training a positive experience and reported improvements to their cognition. Furthermore, in agreement with Douglas et al. (2019), patients asked for improvements to be made to CR packages to allow greater transfer of skills into everyday life, which emphasises the importance of this domain.

In sum, ensuring CR is tailored to mood disorders, including taking into account how to engage in CR during acute mood episodes will be a critical design element as we move forward. There are an increasing number of registered clinical trials and publications in the field guaranteeing continued momentum.