The effectiveness, implementation, and experiences of peer support approaches for mental health: a systematic umbrella review.

BACKGROUND: Peer support for mental health is recommended across international policy guidance and provision. Our systematic umbrella review summarises evidence on the effectiveness, implementation, and experiences of paid peer support approaches for mental health. METHODS: We searched MEDLINE, EMBASE, PsycINFO, The Campbell Collaboration, and The Cochrane Database of Systematic Reviews (2012-2022) for reviews of paid peer support interventions for mental health. The AMSTAR2 assessed quality. Results were synthesised narratively, with implementation reported using the CFIR (Consolidated Framework for Implementation Research). The protocol was registered with PROSPERO (registration number: CRD42022362099). RESULTS: We included 35 reviews (426 primary studies, n = 95-40,927 participants): systematic reviews with (n = 13) or without (n = 13) meta-analysis, or with qualitative synthesis (n = 3), scoping reviews (n = 6). Most reviews were low or critically low (97%) quality, one review was high quality. Effectiveness was investigated in 23 reviews. Results were mixed; there was some evidence from meta-analyses that peer support may improve depression symptoms (particularly perinatal depression), self-efficacy, and recovery. Factors promoting successful implementation, investigated in 9 reviews, included adequate training and supervision, a recovery-oriented workplace, strong leadership, and a supportive and trusting workplace culture with effective collaboration. Barriers included lack of time, resources and funding, and lack of recognised peer support worker (PSW) certification. Experiences of peer support were explored in 11 reviews, with 3 overarching themes: (i) what the PSW role can bring, including recovery and improved wellbeing for service users and PSWs; (ii) confusion over the PSW role, including role ambiguity and unclear boundaries; and (iii) organisational challenges and impact, including low pay, negative non-peer staff attitudes, and lack of support and training. CONCLUSIONS: Peer support may be effective at improving some clinical outcomes, self-efficacy, and recovery. Certain populations, e.g. perinatal populations, may especially benefit from peer support. Potential strategies to successfully implement PSWs include co-production, clearly defined PSW roles, a receptive hierarchical structure and staff, appropriate PSW and staff training with clinical and/or peer supervision alongside safeguarding. Services could benefit from clear, coproduced, setting specific implementation guidelines for PSW. PSW roles tend to be poorly defined and associations between PSW intervention content and impacts need further investigation. Future research should reflect the priorities of providers/service users involved in peer support.

The serotonin theory of depression: a systematic umbrella review of the evidence.

The serotonin hypothesis of depression is still influential. We aimed to synthesise and evaluate evidence on whether depression is associated with lowered serotonin concentration or activity in a systematic umbrella review of the principal relevant areas of research. PubMed, EMBASE and PsycINFO were searched using terms appropriate to each area of research, from their inception until December 2020. Systematic reviews, meta-analyses and large data-set analyses in the following areas were identified: serotonin and serotonin metabolite, 5-HIAA, concentrations in body fluids; serotonin 5-HT1A receptor binding; serotonin transporter (SERT) levels measured by imaging or at post-mortem; tryptophan depletion studies; SERT gene associations and SERT gene-environment interactions. Studies of depression associated with physical conditions and specific subtypes of depression (e.g. bipolar depression) were excluded. Two independent reviewers extracted the data and assessed the quality of included studies using the AMSTAR-2, an adapted AMSTAR-2, or the STREGA for a large genetic study. The certainty of study results was assessed using a modified version of the GRADE. We did not synthesise results of individual meta-analyses because they included overlapping studies. The review was registered with PROSPERO (CRD42020207203). 17 studies were included: 12 systematic reviews and meta-analyses, 1 collaborative meta-analysis, 1 meta-analysis of large cohort studies, 1 systematic review and narrative synthesis, 1 genetic association study and 1 umbrella review. Quality of reviews was variable with some genetic studies of high quality. Two meta-analyses of overlapping studies examining the serotonin metabolite, 5-HIAA, showed no association with depression (largest n = 1002). One meta-analysis of cohort studies of plasma serotonin showed no relationship with depression, and evidence that lowered serotonin concentration was associated with antidepressant use (n = 1869). Two meta-analyses of overlapping studies examining the 5-HT1A receptor (largest n = 561), and three meta-analyses of overlapping studies examining SERT binding (largest n = 1845) showed weak and inconsistent evidence of reduced binding in some areas, which would be consistent with increased synaptic availability of serotonin in people with depression, if this was the original, causal abnormaly. However, effects of prior antidepressant use were not reliably excluded. One meta-analysis of tryptophan depletion studies found no effect in most healthy volunteers (n = 566), but weak evidence of an effect in those with a family history of depression (n = 75). Another systematic review (n = 342) and a sample of ten subsequent studies (n = 407) found no effect in volunteers. No systematic review of tryptophan depletion studies has been performed since 2007. The two largest and highest quality studies of the SERT gene, one genetic association study (n = 115,257) and one collaborative meta-analysis (n = 43,165), revealed no evidence of an association with depression, or of an interaction between genotype, stress and depression. The main areas of serotonin research provide no consistent evidence of there being an association between serotonin and depression, and no support for the hypothesis that depression is caused by lowered serotonin activity or concentrations. Some evidence was consistent with the possibility that long-term antidepressant use reduces serotonin concentration.

An analysis of views about supported reduction or discontinuation of antipsychotic treatment among people with schizophrenia and other psychotic disorders.

BACKGROUND: Antipsychotic medication can reduce psychotic symptoms and risk of relapse in people with schizophrenia and related disorders, but it is not always effective and adverse effects can be significant. We know little of patients' views about continuing or discontinuing antipsychotic treatment. AIMS: To explore the views of people with schizophrenia and other psychotic disorders about continuing their antipsychotic medication or attempting to reduce or discontinue this medication with clinical support. METHODS: We collected quantitative and qualitative data by conducting semi-structured interviews in London, UK. Factors predicting a desire to discontinue medication were explored. Content analysis of qualitative data was undertaken. RESULTS: We interviewed 269 participants. 33% (95% CI, 27 to 39%) were content with taking long-term antipsychotic medication. Others reported they took it reluctantly (19%), accepted it on a temporary basis (24%) or actively disliked it (18%). 31% (95% CI, 25 to 37%) said they would like to try to stop medication with professional support, and 45% (95% CI, 39 to 51%) wanted the opportunity to reduce medication. People who wanted to discontinue had more negative attitudes towards the medication but were otherwise similar to other participants. Wanting to stop or reduce medication was motivated mainly by adverse effects and health concerns. Professional support was identified as potentially helpful to achieve reduction. CONCLUSIONS: This large study reveals that patients are commonly unhappy about the idea of taking antipsychotics on a continuing or life-long basis. Professional support for people who want to try to reduce or stop medication is valued.

The Systemic Assessment Clinic, a Novel Method for Assessing Patients in General Adult Psychiatry: Presentation and Preliminary Service Evaluation.

The traditional model of psychiatric assessment and diagnosis can be criticised as reductive. We developed an innovative model for psychiatric assessment of adult patients referred to our adult mental health team, the Systemic Assessment Clinic, incorporating the principles and techniques of systemic family therapy and dialogical practice into standard psychiatric assessment. We conducted a service evaluation, comparing prospective use of mental health services for patients assessed either in the Systemic Assessment Clinic or in standard assessment. Patients assessed in the Systemic Assessment Clinic had more favourable outcomes than those in standard assessment: they were significantly less likely to need multiple follow-up treatment appointments with a psychiatrist and to be re-referred to mental health services once discharged, indicating reduced healthcare costs. Satisfaction rates for participants attending the systemic assessment clinic were high. Our service evaluation gives preliminary evidence that the Systemic Assessment Clinic could be a potential new model for psychiatric assessment; further evaluation is warranted in a randomised controlled trial.

Experiences of taking neuroleptic medication and impacts on symptoms, sense of self and agency: a systematic review and thematic synthesis of qualitative data.

PURPOSE: Neuroleptic (antipsychotic) drugs reduce psychotic symptoms, but how they achieve these effects and how the drugs' effects are experienced by people who take them are less well understood. The present study describes a synthesis of qualitative data about mental and behavioural alterations associated with taking neuroleptics and how these interact with symptoms of psychosis and people's sense of self and agency. METHODS: Nine databases were searched to identify qualitative literature concerning experiences of taking neuroleptic medication. A thematic synthesis was conducted. RESULTS: Neuroleptics were commonly experienced as producing a distinctive state of lethargy, cognitive slowing, emotional blunting and reduced motivation, which impaired functioning but also had beneficial effects on symptoms of psychosis and some other symptoms (e.g. insomnia). For some people, symptom reduction helped restore a sense of normality and autonomy, but others experienced a loss of important aspects of their personality. Across studies, many people adopted a passive stance towards long-term medication, expressing a sense of resignation, endurance or loss of autonomy. CONCLUSIONS: Neuroleptic drugs modify cognition, emotions and motivation. These effects may be associated with reducing the intensity and impact of symptoms, but also affect people's sense of self and agency. Understanding how the effects of neuroleptics are experienced by those who take them is important in developing a more collaborative approach to drug treatment in psychosis and schizophrenia.

The effect of methylphenidate on very low frequency electroencephalography oscillations in adult ADHD.

Altered very low-frequency electroencephalographic (VLF-EEG) activity is an endophenotype of ADHD in children and adolescents. We investigated VLF-EEG case-control differences in adult samples and the effects of methylphenidate (MPH). A longitudinal case-control study was conducted examining the effects of MPH on VLF-EEG (.02-0.2Hz) during a cued continuous performance task. 41 untreated adults with ADHD and 47 controls were assessed, and 21 cases followed up after MPH treatment, with a similar follow-up for 38 controls (mean follow-up=9.4months). Cases had enhanced frontal and parietal VLF-EEG and increased omission errors. In the whole sample, increased parietal VLF-EEG correlated with increased omission errors. After controlling for subthreshold comorbid symptoms, VLF-EEG case-control differences and treatment effects remained. Post-treatment, a time by group interaction emerged; VLF-EEG and omission errors reduced to the same level as controls, with decreased inattentive symptoms in cases. Reduced VLF-EEG following MPH treatment provides preliminary evidence that changes in VLF-EEG may relate to MPH treatment effects on ADHD symptoms; and that VLF-EEG may be an intermediate phenotype of ADHD. Further studies of the treatment effect of MPH in larger controlled studies are required to formally evaluate any causal link between MPH, VLF-EEG and ADHD symptoms.

An ethics analysis of antipsychotic dose reduction and discontinuation: Principles for supporting recovery from psychosis.

OBJECTIVE: To examine the evidence and practice of antipsychotic dose reduction from the lens of biomedical ethics (specifically principlism) to support evidence-based practice and patient choice and self-determination. METHODS: An overview of the evidence from randomized controlled trials of antipsychotic dose reduction versus maintenance is presented. This is followed by a theoretical examination of the four key biomedical ethical principles of autonomy, nonmaleficence, beneficence, and justice and how they apply in the case of antipsychotic dose reduction. RESULTS: Existing clinical trial research is dominated by relapse as the primary outcome, with dose reduction associated with a higher risk of relapse than maintenance. Few studies have measured other patient-centered outcomes but have shown preliminary evidence for superior cognitive functioning, lower negative symptoms, and better functioning following dose reduction. Respect for autonomy is a cornerstone of psychiatric rehabilitation, and this includes the right of people to choose to reduce or discontinue antipsychotic medication. Reduced capacity for treatment decision making can be supported. Autonomy and appraisal of nonmaleficence and beneficence associated with dose reduction can be facilitated through shared or supported decision making. Clinicians should continue to strive for justice through the fair allocation of resources to support all people who request antipsychotic dose reduction. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Clinicians have a responsibility to balance the four core ethical principles to the best of their ability when supporting a person in their recovery journey. Exploring, trialing, and supporting antipsychotic dose reduction may be part of this process if that is the patient's choice. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

"Stabilise-reduce, stabilise-reduce": A survey of the common practices of deprescribing services and recommendations for future services.

BACKGROUND: Public Health England recently called for the establishment of services to help people to safely stop prescribed drugs associated with dependence and withdrawal, including benzodiazepines, z-drugs, antidepressants, gabapentinoids and opioids. NICE identified a lack of knowledge about the best model for such service delivery. Therefore, we performed a global survey of existing deprescribing services to identify common practices and inform service development. METHODS: We identified existing deprescribing services and interviewed key personnel in these services using an interview co-produced with researchers with lived experience of withdrawal. We summarised the common practices of the services and analysed the interviews using a rapid form of qualitative framework analysis. RESULTS: Thirteen deprescribing services were included (8 UK, 5 from other countries). The common practices in the services were: gradual tapering of medications often over more than a year, and reductions made in a broadly hyperbolic manner (smaller reductions as total dose became lower). Reductions were individualised so that withdrawal symptoms remained tolerable, with the patient leading this decision-making in most services. Support and reassurance were provided throughout the process, sometimes by means of telephone support lines. Psychosocial support for the management of underlying conditions (e.g. CBT, counselling) were provided by the service or through referral. Lived experience was often embedded in services through founders, hiring criteria, peer support and sources of information to guide tapering. CONCLUSION: We found many common practices across existing deprescribing services around the world. We suggest that these ingredients are included in commissioning guidance of future services and suggest directions for further research to clarify best practice.

Psychosocial interventions for people with schizophrenia or psychosis on minimal or no antipsychotic medication: A systematic review.

Antipsychotics are the first-line treatment for people with schizophrenia or psychosis. There is evidence that they can reduce the symptoms of psychosis and risk of relapse. However many people do not respond to these drugs, or experience adverse effects and stop taking them. In the UK, clinical guidelines have stressed the need for research into psychosocial interventions without antipsychotics. This systematic review examines the effects of psychosocial interventions for people with schizophrenia or psychosis who are on no/minimal antipsychotics. Databases were searched for empirical studies investigating a psychosocial intervention in people with a schizophrenia spectrum disorder who were not taking antipsychotics or had received an antipsychotic minimisation strategy. We identified nine interventions tested in 17 studies (N = 2250), including eight randomised controlled trials. Outcomes were generally equal to or in a small number of cases better than the control group (antipsychotics/treatment as usual) for Cognitive Behavioural Therapy (CBT), Need Adapted Treatment and Soteria. The remaining interventions provided some encouraging, but overall inconsistent findings and were Psychosocial Outpatient Treatment, Open Dialogue, Psychosocial Inpatient Treatment, Psychoanalysis/Psychodynamic Psychotherapy, Major Role Therapy, and Milieu Treatment. Study quality was generally low with little recent research. In conclusion, nine psychosocial interventions have been studied for patients on no/minimal antipsychotics. The majority of studies reported outcomes for the intervention which were the same as the control group, however, study quality was problematic. Given the adverse effects of antipsychotics and that many people do not want to take them, high quality trials of psychosocial treatments for people on minimal/no antipsychotics are needed.

Definitions of relapse in trials comparing antipsychotic maintenance with discontinuation or reduction for schizophrenia spectrum disorders: A systematic review.

INTRODUCTION: Avoidance of relapse is the main aim of long-term antipsychotic treatment in schizophrenia, yet how 'relapse' is defined in trials is not well-known. METHODS: We conducted a systematic review of definitions of relapse in trials of continuous antipsychotic treatment compared with discontinuation, intermittent treatment or dose reduction for people with schizophrenia spectrum disorders. Trials were identified from previous Cochrane reviews and a new search. The quality of relapse definitions was rated in terms of reliability and clinical relevance and associations between quality of definitions and trial characteristics and outcome were explored. RESULTS: We identified 82 reports of 81 trials which employed 54 different definitions of relapse. There were 33 definitions in the 35 trials published since 1990, with recent trials employing complex definitions often involving alternative criteria. Only ten primary definitions of relapse required the presence of psychotic symptoms in all cases, and only three specified this in combination with a measure of overall severity or functional decline. Only two definitions specified a duration longer than two days. Relapse definitions were rated as showing good reliability in 37 trials, but only seven showed good clinical relevance. Six trials with definitions that were both reliable and clinically relevant were slightly longer, but did not differ from remaining trials in other characteristics or overall or relative risk of relapse. CONCLUSIONS: Antipsychotic trials define relapse in numerous different ways, and few definitions consistently reflect suggested indications of a clinically significant relapse.

The key role of daytime sleepiness in cognitive functioning of adults with attention deficit hyperactivity disorder.

BACKGROUND: Adults with attention deficit hyperactivity disorder (ADHD) frequently suffer from sleep problems and report high levels of daytime sleepiness compared to neurotypical controls, which has detrimental effect on quality of life. METHODS: We evaluated daytime sleepiness in adults with ADHD compared to neurotypical controls using an observer-rated sleepiness protocol during the Sustained Attention Response Task as well as electroencephalogram (EEG) slowing, a quantitative electroencephalographic measure collected during a short period of wakeful rest. RESULTS: We found that adults with ADHD were significantly sleepier than neurotypical controls during the cognitive task and that this on-task sleepiness contributed to cognitive performance deficits usually attributed to symptoms of ADHD. EEG slowing predicted severity of ADHD symptoms and diagnostic status, and was also related to daytime sleepiness. Frontal EEG slowing as well as increased frontal delta were especially prominent in adults with ADHD. We have validated and adapted an objective observer-rated measure for assessing on-task sleepiness that will contribute to future sleep research in psychology and psychiatry. CONCLUSIONS: These findings indicate that the cognitive performance deficits routinely attributed to ADHD and often conceptualized as cognitive endophenotypes of ADHD are largely due to on-task sleepiness and not exclusively due to ADHD symptom severity. Daytime sleepiness plays a major role in cognitive functioning of adults with ADHD.

Mental health professionals' views and experiences of antipsychotic reduction and discontinuation.

BACKGROUND: The widely established treatment for psychosis is long-term antipsychotic medication. However, many people stop taking this treatment, and request other options. There are also growing concerns about adverse effects, but currently no professional guidelines to support reducing or stopping these drugs. The views and experiences of individual mental health professionals around reducing and stopping antipsychotics are therefore crucial in treatment decisions. METHODS: We conducted 7 focus groups with prescribing psychiatrists and other members of community-based statutory mental health services in London. Participants discussed their views about, experiences, and processes of antipsychotic reduction and discontinuation. Data were analysed using thematic analysis. RESULTS: Participants acknowledged that antipsychotics can have severe adverse effects. They were generally supportive of trying to reduce these drugs to the lowest effective dose, although stopping antipsychotics was less acceptable. Prior experiences of adverse events after reduction or discontinuation meant that both were approached with caution. Reduction was also reported to be hampered by organisational and knowledge barriers. Lack of resources, pressure to discharge, and poor continuity of care were seen as organisational barriers. Knowledge barriers included inadequate evidence about who might be best suited to reduction, and lack of guidance about how this could be done safely. This meant that reduction was often prompted by patients, and sometimes actively discouraged, and stability with maintenance treatment was often favoured. CONCLUSIONS: Concerns about risk and other barriers means that clinicians are often reluctant to implement reduction or discontinuation of antipsychotic medication. In order to increase the treatment options available to service users, more research and guidance on how to minimise the risks of antipsychotic reduction and discontinuation is required to enable clinicians to engage more constructively with service users requests, offering people more choice and control in managing their mental health condition.

The effects of emotional lability, mind wandering and sleep quality on ADHD symptom severity in adults with ADHD.

Mind wandering, emotional lability and sleep quality are currently mostly independently investigated but are all interlinked and play a major role is adult attention-deficit/ hyperactivity disorder (ADHD). Emotional lability is a core feature of the disorder, excessive mind wandering has recently been linked to symptoms and impairments of ADHD and poor sleep quality is experienced by a clear majority of adults with ADHD. All three phenomena lead to functional impairment in ADHD, however their relationship to each other and to ADHD symptom severity is not well understood. Here we used serial multiple mediation models to examine the influence of mind wandering, sleep quality and emotional lability on ADHD symptom severity. 81 adults diagnosed with ADHD participated in this study. We found that mind wandering and emotional lability predicted ADHD symptom severity and that mind wandering, emotional lability and sleep quality were all linked and significantly contributed to the symptomatology of adult ADHD. Mind wandering was found to lead to emotional lability which in turn lead to ADHD symptom severity; and poor sleep quality was found to exacerbate mind wandering leading to ADHD symptoms. Future research should employ objective on-task measures of mind wandering, sleepiness and emotional lability to investigate the neural basis of these impairing deficits in ADHD.

Randomised controlled trial of gradual antipsychotic reduction and discontinuation in people with schizophrenia and related disorders: the RADAR trial (Research into Antipsychotic Discontinuation and Reduction).

INTRODUCTION: Antipsychotic medication is effective in reducing acute symptoms of psychosis, but it has a range of potentially serious and debilitating adverse effects and is often disliked by patients. It is therefore essential it is only used when benefits outweigh harms. Although multiple trials conducted with people with schizophrenia indicate an increased risk of relapse in the short-term following abrupt antipsychotic discontinuation, there is little evidence about the long-term outcome of a gradual process of reduction and discontinuation on social functioning, relapse and other outcomes. METHODS AND ANALYSIS: This is a multicentre, randomised controlled trial involving people with schizophrenia and related disorders who have had more than one episode. Participants are randomised to have a clinically-supervised, gradual reduction of antipsychotic medication, leading to discontinuation when possible, or to continue with maintenance treatment. Blinded follow-up assessments are conducted at 6, 12 and 24 months and the primary outcome is social functioning, measured by the Social Functioning Scale at 24 months. A minimum of 134 evaluable participants provides 90% power to detect a five-point difference, and 206 to detect a four-point difference. Secondary outcomes include severe relapse (admission to hospital) and the study is also intended to detect a minimum 10% difference in severe relapse, which requires 402 participants, assuming a 15% loss to follow-up. Other secondary outcomes include all relapses, as identified by an independent and blinded endpoint committee, symptoms measured by the Positive and Negative Syndrome Scale, quality of life, adverse effects, self-rated recovery and neuropsychological measures. Enrolment started in 2016. The trial is scheduled to finish in June 2022. ETHICS AND DISSEMINATION: Ethical approval was initially obtained on 27 October 2016 (UK Research Ethics Committee reference 16/LO/1507). Results will be published in peer-reviewed journals and disseminated to the public. TRIAL REGISTRATION NUMBER: ISRCTN90298520. EudraCT: 2016-000709-36. Pre-results.

Cannabinoids in attention-deficit/hyperactivity disorder: A randomised-controlled trial.

Adults with ADHD describe self-medicating with cannabis, with some reporting a preference for cannabis over ADHD medications. A small number of psychiatrists in the US prescribe cannabis medication for ADHD, despite there being no evidence from randomised controlled studies. The EMA-C trial (Experimental Medicine in ADHD-Cannabinoids) was a pilot randomised placebo-controlled experimental study of a cannabinoid medication, Sativex Oromucosal Spray, in 30 adults with ADHD. The primary outcome was cognitive performance and activity level using the QbTest. Secondary outcomes included ADHD and emotional lability (EL) symptoms. From 17.07.14 to 18.06.15, 30 participants were randomly assigned to the active (n=15) or placebo (n=15) group. For the primary outcome, no significant difference was found in the ITT analysis although the overall pattern of scores was such that the active group usually had scores that were better than the placebo group (Est=-0.17, 95%CI-0.40 to 0.07, p=0.16, n=15/11 active/placebo). For secondary outcomes Sativex was associated with a nominally significant improvement in hyperactivity/impulsivity (p=0.03) and a cognitive measure of inhibition (p=0.05), and a trend towards improvement for inattention (p=0.10) and EL (p=0.11). Per-protocol effects were higher. Results did not meet significance following adjustment for multiple testing. One serious (muscular seizures/spasms) and three mild adverse events occurred in the active group and one serious (cardiovascular problems) adverse event in the placebo group. Adults with ADHD may represent a subgroup of individuals who experience a reduction of symptoms and no cognitive impairments following cannabinoid use. While not definitive, this study provides preliminary evidence supporting the self-medication theory of cannabis use in ADHD and the need for further studies of the endocannabinoid system in ADHD.

The effect of omega-3 polyunsaturated fatty acid supplementation on emotional dysregulation, oppositional behaviour and conduct problems in ADHD: A systematic review and meta-analysis.

BACKGROUND: A number of randomised controlled trials report a beneficial effect of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on emotional lability (EL) and related domains (e.g. oppositional behaviour, conduct problems). Given that n-3 PUFA supplementation shows a significant effect on reducing symptoms of attention-deficit/hyperactivity disorder (ADHD) and that EL and related behaviours commonly co-occurs with ADHD, it is important that there is a more conclusive picture as to the effect of n-3 PUFA on these co-occurring clinical domains. METHODS: Databases (Ovid Medline, Embase, Psychinfo) were searched for trials assessing the effects of n-3 PUFA on EL, oppositional behaviour, aggression and conduct problems. We included trials in children who had ADHD or a related neurodevelopmental disorder. RESULTS: Of the 1775 identified studies, 10 were included in the meta-analysis. In the primary analyses n-3 PUFA supplementation did not show improvements in measures of EL, oppositional behaviour, conduct problems or aggression. However subgroup analyses of higher quality studies and those meeting strict inclusion criteria found a significant reduction in EL and oppositional behaviour. LIMITATIONS: A number of treatment effects may have failed to reach statistical significance due to small sample sizes and within and between study heterogeneity in terms of design and study participants. CONCLUSIONS: These results exclude the possibility of moderate to large effects. They provide suggestive evidence of small effects of n-3 PUFA on reducing EL and oppositional behaviour in subgroups of children with ADHD.

Omega-3 polyunsaturated fatty acid supplementation and cognition: A systematic review and meta-analysis.

BACKGROUND: Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are promoted as cognitive enhancers with consumption recommended in the general population and those with neurocognitive deficits such as attention deficit hyperactivity disorder (ADHD). However, evidence from randomised placebo-controlled trials is inconclusive. AIMS: This study aimed to conduct a systematic review and meta-analysis examining the effect of n-3 PUFA supplementation on cognition in healthy populations and those with ADHD and related disorders (RDs). METHODS: Databases were searched for randomised controlled trials (RCTs) in adults and school-aged children (who were healthy and typically developing (TD) or had ADHD or a related-neurodevelopmental disorder (ADHD+RD) which assessed the effects of n-3 PUFA on cognition. RESULTS: In the 24 included studies n-3 PUFA supplementation, in the whole sample and the TD and ADHD+RD subgroup, did not show improvements in any of the cognitive performance measures. In those with low n-3 PUFA status, supplementation improved short-term memory. CONCLUSIONS: There is marginal evidence that n-3 PUFA supplementation effects cognition in those who are n-3 PUFA deficient. However, there is no evidence of an effect in the general population or those with neurodevelopmental disorders. This has important implications given the widespread advertisement and consumption of n-3 PUFA; claims of cognitive benefit should be narrowed.