Cognitive dysfunction in bipolar disorder

Prof Anabel Martinez-Aran (University of Barcelona, Spain) described cognitive dysfunction as a poorly controlled and relevant aspect of psychiatric disorders that cuts across traditional diagnostic boundaries.

While there is large cognitive diversity in bipolar disorder (BD), impairment is seen in 40% to 60% of patients and persists during clinical remission. It involves the domains of memory, attention and executive functions and has a significant impact on functional recovery. Cognitive dysfunction is associated with longer duration of illness and higher number of manic episodes.

Has a significant impact on functional recovery

It is important to recognise that there are many sources of cognitive dysfunction in BD. Primary impairment may be due to altered neurodevelopment, obstetric complications and delayed neuroprogression. Secondary causes include subthreshold depressive symptoms, comorbity and side effects of medication. But regardless of the cause, cognitive deficits impact functional outcomes.

There are multiple approaches to restoring cognition and functioning in BD, including use of medication, treating comorbidities, physical exercise, and cognitive and functional remediation.

A number of studies have shown the benefits of cognitive remediation in BD. Researchers have generally seen reduction in residual depressive symptoms, improvement in psychosocial functioning and QoL, and mild cognitive improvement.

Functional Remediation - filling the gap

Prof Martinez-Aran introduced a new approach - that of Functional Remediation. Functional remediation is an intervention that aims to fill the gap between clinical remission and functional recovery. Its goal is to restore psychosocial functioning in patients with BD through 'ecological' neurocognitive techniques for day-to-day life.

Fill the gap between clinical remission and functional recovery

Functional Remediation increases patient insight through education about cognitive symptoms and their impact on daily life. It gives patients strategies to manage these symptoms, mainly in the domains of attention, memory and executive functions. The intervention adopts a neurocognitive behavioural approach that includes modelling techniques, role playing, self-instructions, positive reinforcement and metacognition. Real-world functioning is the main target.

Real-world functioning is the main target

The efficacy of Functional Remediation was assessed in a multicentre randomised controlled trial. At 10 sites, 239 patients with euthymic BD were randomised to receive Functional Remediation (77 patients, 21 sessions, 90 minutes each), psychoeducation (82 patients, 21 sessions) or treatment as usual (80 patients, 6 months). The primary outcome was FAST change from baseline.

At 6 months, there was no significant effect of Functional Remediation on neurocognitive variables. In the interpersonal and occupational FAST domains, functional improvement in the Functional Remediation group was significantly better than the other groups.

A post-hoc analysis looked at only patients with BD-II (53 patients). In this subgroup, functional improvement (FAST) and changes in subclinical depressive symptoms (HAM-D) were better in the Functional Remediation group compared to psychoeducation or treatment as usual.

In the long run

Prof Martinez-Aran and colleagues looked into whether this functional improvement is maintained over time, and whether there are changes in neuropsychological performance.

Functional Remediation remained effective over time

In the subgroup of 172 follow-up completers, follow-up assessment was carried out after 12 months. They found that Functional Remediation remained effective over time, with improvements in FAST total score and Autonomy domain. Furthermore, long-term treatment led to an improved performance in verbal memory.

Researchers are now developing an e-neurocognitive module as an adjunct to the Functional Remediation programme for BD. This neurocognitive and social cognition computerised training will consist of 24 sessions for 2 hours a week.

Looking ahead

Prof Martinez-Aran highlighted that further research is needed to identify the key components of cognitive and functional remediation. Interest is also moving into the area of cognitive reserve enhancement to prevent the impact of cognitive deficits on functional impairment.

Key:

BD, bipolar disorder; FAST, Functional Assessment Staging Test; HAM-D, Hamilton Rating Scale for Depression; QoL, quality of life.