BackgroundDepression is considered to have the highest disability burden of all conditions. Although treatment-resistant depression (TRD) is a key contributor to that burden, there is little understanding of the best treatment approaches for it and specifically the effectiveness of available augmentation approaches.AimsWe conducted a systematic review and meta-analysis to search and quantify the evidence of psychological and pharmacological augmentation interventions for TRD.MethodParticipants with TRD (defined as insufficient response to at least two antidepressants) were randomised to at least one augmentation treatment in the trial. Pre-post analysis assessed treatment effectiveness, providing an effect size (ES) independent of comparator interventions.ResultsOf 28 trials, 3 investigated psychological treatments and 25 examined pharmacological interventions. Pre-post analyses demonstrated N-methyl-d-aspartate-targeting drugs to have the highest ES (ES = 1.48, 95% CI 1.25–1.71). Other than aripiprazole (four studies, ES = 1.33, 95% CI 1.23–1.44) and lithium (three studies, ES = 1.00, 95% CI 0.81–1.20), treatments were each investigated in less than three studies. Overall, pharmacological (ES = 1.19, 95% CI 1.08–1.30) and psychological (ES = 1.43, 95% CI 0.50–2.36) therapies yielded higher ESs than pill placebo (ES = 0.78, 95% CI 0.66–0.91) and psychological control (ES = 0.94, 95% CI 0.36–1.52).ConclusionsDespite being used widely in clinical practice, the evidence for augmentation treatments in TRD is sparse. Although pre-post meta-analyses are limited by the absence of direct comparison, this work finds promising evidence across treatment modalities.Declaration of interestIn the past 3 years, A.H.Y. received honoraria for speaking from AstraZeneca, Lundbeck, Eli Lilly and Sunovion; honoraria for consulting from Allergan, Livanova and Lundbeck, Sunovion and Janssen; and research grant support from Janssen. In the past 3 years, A.J.C. received honoraria for speaking from AstraZeneca and Lundbeck; honoraria for consulting with Allergan, Janssen, Livanova, Lundbeck and Sandoz; support for conference attendance from Janssen; and research grant support from Lundbeck. B.B. has recently been (soon to be) on the speakers/advisory board for Hexal, Lilly, Lundbeck, Mundipharma, Pfizer, and Servier. No other conflicts of interest.

Objectives Cognitive remediation therapy (CRT) may benefit people with bipolar disorder type I and II for whom cognitive impairment is a major contributor to disability. Extensive research has demonstrated CRT to improve cognition and psychosocial functioning in people with different diagnoses, but randomised trials of evidenced therapy programmes are lacking for bipolar disorders. The Cognitive Remediation in Bipolar (CRiB) study aimed to determine whether an established CRT programme is feasible and acceptable for people with bipolar disorders. Methods This proof‐of‐concept, single‐blind randomised trial recruited participants aged 18‐65 with bipolar disorder, not currently experiencing an episode. They were 1:1 block randomised to treatment‐as‐usual (TAU) with or without individual CRT for 12 weeks. The partly computerised CRT programme (“CIRCuiTS”) was therapist‐led and is evidence‐based from trials in those with psychotic illnesses. Data were collected and analysed by investigators blinded to group allocation. The main outcomes (week 13 and 25) examined participant retention, intervention feasibility and putative effects of CRT on cognitive and psychosocial functioning via intention‐to‐treat analyses. Trial registration: ISRCTN ID32290525. Results Sixty participants were recruited (02/2016‐06/2018) and randomised to CRT (n = 29) or TAU (n = 31). Trial withdrawals were equivalent (CRT n = 2/29; TAU n = 5/31). CRT satisfaction indicated high acceptability. Intention‐to‐treat analyses (N = 60) demonstrated greater improvements for CRT‐ than TAU‐randomised participants: at both week 13 and 25, CIRCuiTS participants showed larger improvements in the following domains (week 25 effect sizes reported here): IQ (SES = 0.71, 95% CI [0.29,1.13]), working memory (SES = 0.70, 95% CI [0.31,1.10]), executive function (SES = 0.93, 95% CI [0.33,1.54]), psychosocial functioning (SES = 0.49, 95% CI [0.18,0.80]) and goal attainment (SES = 2.02, 95% CI [0.89,3.14]). No serious adverse events were reported. Conclusions CRT is feasible for individuals with bipolar disorders and may enhance cognition and functioning. The reported effect sizes from this proof‐of‐concept trial encourage further investigation in a definitive trial.

Background:Patients with bipolar disorder (BD) suffer from cognitive deficits across several domains. The association between cognitive performance and psychosocial functioning has led to the emergence of cognition as a treatment target.Objective: This study reviews the existing literature on cognitive enhancement interventions for people with BD, focusing on different treatment approaches and methodological quality. Methods:We conducted a systematic search following the PRISMA guidelines. Sample characteristics and main outcomes for each study and treatment characteristics for each approach were extracted. Study quality was assessed using the Clinical Trials Assessment Measure (CTAM) and Cochrane Collaboration's Risk of Bias tool by independent raters.Results: Eleven articles reporting data from seven original studies were identified encompassing 471 participants. Two treatment approaches were identified, cognitive and functional remediation. For controlled studies, methodological quality was modest (average CTAM score = 60.3), while the overall risk of bias was considered moderate. Beneficial effects on cognitive or functional outcomes were reported in the majority of studies (91%), but these findings were isolated and not replicated across studies. Key methodological limitations included small sample sizes, poor description of randomization process, high attrition rates, and participant exclusion from the analysis. Conclusions:Findings are promising but preliminary. Quality studies were few and mostly underpowered. Heterogeneity in sample characteristics, outcome measures, and treatment approaches further limit the ability to generalize findings. Adequately powered trials are required to replicate initial findings, while moderators of treatment response and mechanisms of transfer need to be explored. K E Y W O R D S bipolar disorder, cognition, cognitive remediation, functional remediation, functioning, methodological quality | 217 TSAPEKOS ET Al