Neuropsychological and socio-occupational functioning in young psychiatric outpatients: a longitudinal investigation

BACKGROUND

Clinical symptoms and neuropsychological deficits are longitudinally associated with functional outcome in chronic psychiatric cohorts. The current study extended these findings to young and early-course psychiatric outpatients, with the aim of identifying cognitive markers that predict later socio-occupational functioning.

METHODS

At baseline, 183 young psychiatric outpatients were assessed. Ninety-three returned for follow-up (M = 21.6 years old; SD = 4.5) with an average re-assessment interval of 21.6 months (SD = 7.0), and primary diagnoses of major depressive disorder (n = 34), bipolar disorder (n = 29), or psychosis (n = 30). The primary outcome measure was cross-validated with various other functional measures and structural equation modelling was used to map out the interrelationships between predictors and later functional outcome.

RESULTS

Good socio-occupational functioning at follow-up was associated with better quality of life, less disability, current employment and being in a romantic relationship. The final structural equation model explained 47.5% of the variability in functional outcome at follow-up, with baseline neuropsychological functioning (a composite of memory, working memory and attentional switching) the best independent predictor of later functional outcome. Notably, depressive and negative symptoms were only associated with functioning cross-sectionally. Diagnosis at follow-up was not associated with functional outcome.

CONCLUSIONS

Neuropsychological functioning was the single best predictor of later socio-occupational outcome among young psychiatric outpatients. Therefore, framing psychiatric disorders along a neuropsychological continuum is likely to be more useful in predicting functional trajectory than traditional symptom-based classification systems. The current findings also have implications for early intervention utilising cognitive remediation approaches.

In vivo glutathione levels in young persons with bipolar disorder: a magnetic resonance spectroscopy study

Oxidative stress has recently been reported to assume a significant role in the pathophysiology of bipolar disorder. Several studies have demonstrated the replenishment of glutathione (GSH) diminishes oxidative cellular damage and ameliorates depressive symptoms in this disorder. Whilst the mechanism by which GSH exerts any clinical effect is unknown it has been proposed that it involves the bolstering of antioxidant defences by increasing the bioavailability of GSH, which in turn reverses clinical symptoms of depression. Such a proposal is predicated on the implicit assumption that GSH is diminished in these patients prior to GSH supplementation. However hitherto no study has reported in vivo measures of GSH in patients with bipolar disorder. Using magnetic resonance spectroscopy we obtained in vivo measures of GSH in young people with bipolar disorder and contrasted these with matched healthy controls. Young people with bipolar disorder were found to have no diminution in baseline GSH concentration and, furthermore, no significant correlations were found between GSH and clinical scores of depression or mania. The results do not support the hypothesis that oxidative stress is involved in the primary pathophysiology of bipolar disorder.

Delayed sleep phase in young people with unipolar or bipolar affective disorders

BACKGROUND

Circadian disturbances may play a key role in the pathogenesis of some forms of mood disorders. Despite marked changes in circadian rhythms during the normal course of adolescence and young adulthood, less is known about changes in the 24-h sleep-wake cycle in young persons with mood disorders.

METHODS

Seventy-five young participants with mood disorders (unipolar: n=46, 20.1 ± 4.7 years old; bipolar I or II: n=29, 23.2 ± 4.3) and 20 healthy participants (24.8 ± 2.5 years old) underwent actigraphy monitoring during a depressive phase over seven consecutive days and nights. Sleep phase delay was defined as mean sleep onset ≥ 1:30 am and/or sleep offset ≥ 1 0:00 am.

RESULTS

A delayed sleep phase was found in 62% of participants with bipolar disorders when depressed, compared with 30% of those with unipolar depression (χ(2)=6.0, p=0.014) and 10% of control participants (χ(2)=11.2, p<0.001). Sleep offset times were significantly later in subjects with mood disorders compared to the control group, and later in those with bipolar as compared with unipolar disorders (all p ≤ 0.043).

LIMITATIONS

This study was cross-sectional and the depressed groups were somewhat younger compared to the healthy controls. Longitudinal studies are required to determine the predictive significance of these findings.

CONCLUSIONS

Young patients with mood disorders, especially those with bipolar disorders, are particularly likely to have a delayed sleep phase. Therapies focused on advancing sleep phase may be of specific benefit to these young persons.

Frequent alcohol, nicotine or cannabis use is common in young persons presenting for mental healthcare: a cross-sectional study

OBJECTIVES

To determine the prevalence of recent alcohol, nicotine or cannabis use in young persons presenting for mental healthcare.

DESIGN

A cross-sectional study of young people seeking mental healthcare completed self-report questionnaires regarding their use of alcohol, nicotine or cannabis.

SETTING

Data were collected from two sites as part of the national headspace services programme.

PARTICIPANTS

2122 young people aged 12-30 years provided information as part of a patient register; a subset of N=522 participants also provided more detailed information about their patterns of alcohol use.

OUTCOME MEASURES

Prevalence levels of recent alcohol, nicotine or cannabis use within relevant age bands (12-17, 18-19 and 20-30) or primary diagnostic categories.

RESULTS

The rates for use at least weekly of alcohol for the three age bands were 12%, 39% and 45%, and for cannabis 7%, 14% and 18%, respectively. The rates of daily nicotine use for the three age bands were 23%, 36% and 41%. The pattern of alcohol use was characterised by few abstainers as well as many risky drinkers. Age of onset across all three substances was approximately 15 years. Individuals who used any of the three substances more frequently were likely to be older, male or have psychotic or bipolar disorders.

CONCLUSIONS

Frequent use of alcohol, nicotine or cannabis in young people seeking mental healthcare is common. Given the restricted legal access, the patterns of use in those aged 12-17 years are particularly notable. Reductions in substance use needs to be prioritised within services for at-risk young people.

Applying clinical staging to young people who present for mental health care

AIM

The study aims to apply clinical staging to young people who present for mental health care; to describe the demographic features, patterns of psychological symptoms, disability correlates and clinical stages of those young people; and to report longitudinal estimates of progression from less to more severe stages.

METHODS

The study uses cross-sectional and longitudinal assessments of young people managed in specialized youth clinics. On the basis of clinical records, subjects were assigned to a specific clinical 'stage' (i.e. 'help-seeking', 'attenuated syndrome', 'discrete disorder' or 'persistent or recurrent illness').

RESULTS

Young people (n = 209, mean age = 19.9 years (range = 12-30 years), 48% female) were selected from a broader cohort of n = 1483 subjects. Ten percent were assigned to the earliest 'help-seeking' stage, 54% to the 'attenuated syndrome' stage, 25% to the 'discrete disorder' stage and 11% to the later 'persistent or recurrent illness' stage. The interrater reliability of independent ratings at baseline was acceptable (κ = 0.71). Subjects assigned to the 'attenuated syndrome' stage reported symptom and disability scores that were similar to those assigned to later stages. Longitudinally (median = 48 weeks), transition to later clinical stages were 11% of the 'help-seeking', 19% of the 'attenuated syndrome' and 33% of the 'discrete disorder' groups.

CONCLUSION

Among young people presenting for mental health care, most are clinically staged as having 'attenuated syndromes'. Despite access to specialized treatment, a significant number progress to more severe or persistent disorders.

Distinguishing young people with emerging bipolar disorders from those with unipolar depression

BACKGROUND

To facilitate early intervention, there is a need to distinguish unipolar versus bipolar illness trajectories in adolescents and young adults with adult-type mood disorders.

METHODS

Detailed clinical and neuropsychological evaluation of 308 young persons (aged 12 to 30 years) with moderately severe unipolar and bipolar affective disorders.

RESULTS

Almost 30% (90/308) of young people (mean age=19.4±4.4yr) presenting for care with affective disorders met criteria for a bipolar-type syndrome (26% with bipolar I). Subjects with bipolar- and unipolar-type syndromes were of similar age (19.8 vs. 19.2yr) and reported comparable ages of onset (14.5 vs. 14.3yr). Clinically, those subjects with unipolar and bipolar-type disorders reported similar levels of psychological distress, depressive symptoms, current role impairment, neuropsychological dysfunction and alcohol or other substance misuse. Subjects with unipolar disorders reported more social anxiety (p<0.01). Subjects with bipolar disorders were more likely to report a family history of bipolar (21% vs. 11%; [χ(2)=4.0, p<.05]) or psychotic (19% vs. 9%; [χ(2)=5.5, p<.05]), or substance misuse (35% vs. 23%; [χ(2)=3.9, p<.05]), but not depressive (48% vs. 53%; χ(2)=0.3, p=.582]) disorders.

CONCLUSIONS

Young subjects with bipolar disorders were best discriminated by a family history of bipolar, psychotic or substance use disorders. Early in the course of illness, clinical features of depression, or neuropsychological function, do not readily differentiate the two illness trajectories.

Thoughts of death or suicidal ideation are common in young people aged 12 to 30 years presenting for mental health care

BACKGROUND

Reducing suicidal behaviour is a major public health goal. Expanding access to care has been identified as a key strategy. In Australia, a national network of primary-care based services (headspace) has been established for young people with mental ill-health. This study determines the socio-demographic, psychopathological and illness-stage correlates of suicidal ideation in young persons attending headspace services.

METHODS

Suicidal ideation was recorded using the specific suicide item of the Hamilton Depression Rating Scale (HDRS) in a cohort of subjects aged 12-30 years (N = 494) attending headspace services.

RESULTS

Of the 494 young persons assessed, 32% (158/494) had a positive response to any level of the HDRS suicide item, consisting of 16% (77/494) reporting that life was not worth living and a further 16% (81/494) reported thoughts of death or suicidal ideation. Young women (19%; 94/494) were more likely to report any positive response as compared with young men (13%; 64/494) [χ²(2,494) = 13.6, p < .01]. Those with 'attenuated syndromes' reported positive responses at rates comparable to those with more established disorders (35% vs. 34%; χ²(1,347) = 0.0, p = 0.87). However, more serious levels of suicidal ideation were more common in those with depressive disorders or later stages of illness. In multivariate analyses, the major predictors of the degree of suicidal ideation were increasing levels of clinician-rated depressive symptoms (beta = 0.595, p < .001), general psychopathology (beta = 0.198, p < .01), and self-reported distress (beta = 0.172, p < .05).

CONCLUSIONS

Feelings that life is not worth living, thoughts of death or suicidal ideation are common in young people seeking mental health care. These at-risk cognitions are evident before many of these individuals develop severe or persistent mental disorders. Thoughts of death or suicidal ideation may well need to be a primary intervention target in these young people.

A systematic review of resting-state functional-MRI studies in major depression

BACKGROUND

To evaluate the literature pertaining to the use of resting-state functional magnetic resonance imaging (fMRI) in Major Depression (MD).

METHODS

A search for papers published in English was conducted using MedLine, Embase, PsycINFO, OvidSP, and ScienceDirect with the following words: resting state, depression, MRI, affective, and default-mode.

RESULTS

The findings from 16 resting-state fMRI studies on MD are tabulated. Some common findings are discussed in further detail.

CONCLUSION

The use of resting-state fMRI in MD research has yielded a number of significant findings that provide the basis for understanding the pathophysiology of depressive symptoms. Of particular note and deserving of further research are the roles of the cortico-limbic mood regulating circuit (MRC) and the interaction between task-positive and task-negative networks in MD. There is increasing interest in the use of resting-state fMRI in the study of psychiatric conditions, and continued improvement in technique and methodology will prove valuable in future research.

Mismatch negativity/P3a complex in young people with psychiatric disorders: a cluster analysis

BACKGROUND

We have recently shown that the event-related potential biomarkers, mismatch negativity (MMN) and P3a, are similarly impaired in young patients with schizophrenia- and affective-spectrum psychoses as well as those with bipolar disorder. A data driven approach may help to further elucidate novel patterns of MMN/P3a amplitudes that characterise distinct subgroups in patients with emerging psychiatric disorders.

METHODS

Eighty seven outpatients (16 to 30 years) were assessed: 19 diagnosed with a depressive disorder; 26 with a bipolar disorder; and 42 with a psychotic disorder. The MMN/P3a complex was elicited using a two-tone passive auditory oddball paradigm with duration deviant tones. Hierarchical cluster analysis utilising frontal, central and temporal neurophysiological variables was conducted.

RESULTS

Three clusters were determined: the 'globally impaired' cluster (n = 53) displayed reduced frontal and temporal MMN as well as reduced central P3a amplitudes; the 'largest frontal MMN' cluster (n = 17) were distinguished by increased frontal MMN amplitudes and the 'largest temporal MMN' cluster (n = 17) was characterised by increases in temporal MMN only. Notably, 55% of those in the globally impaired cluster were diagnosed with schizophrenia-spectrum disorder, whereas the three patient subgroups were equally represented in the remaining two clusters. The three cluster-groups did not differ in their current symptomatology; however, the globally impaired cluster was the most neuropsychologically impaired, compared with controls.

CONCLUSIONS

These findings suggest that in emerging psychiatric disorders there are distinct MMN/P3a profiles of patient subgroups independent of current symptomatology. Schizophrenia-spectrum patients tended to show the most global impairments in this neurophysiological complex. Two other subgroups of patients were found to have neurophysiological profiles suggestive of quite different neurobiological (and hence, treatment) implications.

Sex differences in brain maturation as measured using event-related potentials

Little is known about how sex influences functional brain maturation. The current study investigated sex differences in the maturation of event-related potential (ERP) amplitudes during an auditory oddball task (N = 170; age = 6-17 years). Performance improved with age. N200 amplitude declined with age: parietal sites showed earlier development than temporal and frontal locations. Girls showed greater bilateral frontal P300 amplitude development, approaching the higher values observed in boys during childhood. After controlling for age, right frontal P300 amplitude was associated with reaction time in girls. The findings demonstrate sex differences in ERP maturation in line with behavioral and neuroimaging studies.

A systematic review of functional magnetic resonance imaging and diffusion tensor imaging modalities used in presurgical planning of brain tumour resection

Historically, brain tumour resection has relied upon standardised anatomical atlases and classical mapping techniques for successful resection. While these have provided adequate results in the past, the emergence of new technologies has heralded a wave of less invasive, patient-specific techniques for the mapping of brain function. Functional magnetic resonance imaging (fMRI) and, more recently, diffusion tensor imaging (DTI) are two such techniques. While fMRI is able to highlight localisation of function within the cortex, DTI represents the only technique able to elucidate white matter structures in vivo. Used in conjunction, both of these techniques provide important presurgical information for thorough preoperative planning, as well as intraoperatively via integration into frameless stereotactic neuronavigational systems. Together, these techniques show great promise for improved neurosurgical outcomes. While further research is required for more widespread clinical validity and acceptance, results from the literature provide a clear road map for future research and development to cement these techniques into the clinical setup of neurosurgical departments globally.

A meta-analysis of cognitive deficits in first-episode Major Depressive Disorder

BACKGROUND

Recurrent-episode Major Depressive Disorder (MDD) is associated with a number of neuropsychological deficits. To date, less is known about whether these are present in the first-episode. The current aim was to systematically evaluate the literature on first-episode MDD to determine whether cognition may be a feasible target for early identification and intervention.

METHODS

Electronic database searches were conducted to examine neuropsychological studies in adults (mean age greater than 18 years old) with a first-episode of MDD. Effect sizes were pooled by cognitive domain. Using meta-regression techniques, demographic and clinical factors potentially influencing heterogeneity of neuropsychological outcome were also investigated.

RESULTS

The 15 independent samples reviewed yielded data for 644 patients with a mean age of 39.36 years (SD=10.21). Significant cognitive deficits were identified (small to medium effect sizes) for psychomotor speed, attention, visual learning and memory, and all aspects of executive functioning. Symptom remission, inpatient status, antidepressant use, age and educational attainment, each significantly contributed to heterogeneity in effect sizes in at least one cognitive domain.

LIMITATIONS

Reviewed studies were limited by small sample sizes and often did not report important demographic and clinical characteristics of patients.

CONCLUSIONS

The current meta-analysis was the first to systematically demonstrate reduced neuropsychological functioning in first-episode MDD. Psychomotor speed and memory functioning were associated with clinical state, whereas attention and executive functioning were more likely trait-markers. Demographic factors were also associated with heterogeneity across studies. Overall, cognitive deficits appear to be feasible early markers and targets for early intervention in MDD.

Neurophysiological biomarkers support bipolar-spectrum disorders within psychosis cluster

BACKGROUND

Mismatch negativity (MMN) and P3a are event-related potentials that index deviance detection and the orienting response, respectively. We have previously shown that the MMN/P3a complex is impaired in patients with schizophrenia and affective spectrum psychoses, which suggests that it may index a common pathophysiology and argues against the purported specificity in schizophrenia. Further research is warranted to determine whether patients with bipolar-spectrum disorders show similar impairments in these biomarkers.

METHODS

We assessed patients aged 15-30 years with early schizophrenia-spectrum disorders (schizophrenia, schizoaffective disorder, schizophreniform disorder), early bipolar-spectrum disorders (bipolar I or II, with and without psychotic features) and healthy, matched controls. We acquired MMN/P3a amplitudes during a 2-tone, auditory paradigm with 8% duration deviants. Clinical, psychosocial and neuro psychological assessments were also undertaken.

RESULTS

We included 20 patients with schizophrenia-spectrum disorders, 20 with bipolar-spectrum disorders and 20 controls in our study. Both patient groups showed significantly reduced frontocentral MMN and central P3a amplitudes. The schizophrenia-spectrum group had additional impairments in left temporal MMN and frontal P3a. Both patient groups performed worse than controls across psychosocial and clinical measures; however, only the schizophrenia-spectrum group performed significantly worse than controls for cognitive measures. Correlational analyses between patient groups revealed associations between frontocentral or left temporal MMN and psychiatric symptomatology or quality of life measures.

LIMITATIONS

Limitations to our study include the modest sample size and the lack of control with regards to the effects of other (i.e., nonantipsychotic) psychotropic medications.

CONCLUSION

Compared with patients in early stages of schizophrenia-spectrum disorders, those in the early stages of bipolar-spectrum disorders are similarly impaired in established biomarkers for schizophrenia. These findings support a shared diathesis model for psychotic and bipolar disorders. Furthermore, MMN/P3a may be a biomarker for a broader pathophysiology that overlaps traditional diagnostic clusters.

Targeted primary care-based mental health services for young Australians

OBJECTIVE

To assess the extent to which youth-specific, mental health care centres engage young people (12-25 years of age) in treatment, and to report the degree of psychological distress, and the diagnostic type, stage of illness, and psychosocial and vocational impairment evident in these young people.

DESIGN AND SETTING

Standardised clinical and self-report assessments of consecutive presentations at two youth-specific centres from October 2007 to December 2009. Both sites are operated by the Brain and Mind Research Institute in Sydney, Australia, as part of headspace: the National Youth Mental Health Foundation mental health care service.

RESULTS

Of 1260 young people assessed, 53% were male, and the mean (SD) age was 18.1 (3.9) years. Over 40% of the young people were self-referred, or their assessment was arranged by family or friends, or by other social agencies; 30% of young people were referred from other primary health providers. Almost 70% reported high or very high levels of psychological distress. More than 60% of subjects reported having 2 or more days "unable to function" within the past month, and clinicians rated over 50% as having at least moderate difficulty in social/occupational functioning. Importantly, 25% of subjects were receiving income support. Two-thirds of subjects were rated as being at the early stage of an illness, and almost half were diagnosed with anxiety or depressive syndromes.

CONCLUSIONS

Targeted youth-specific mental health services, based in primary care settings, are able to engage young Australians, particularly young men, in treatment. Many of these young people report established patterns of psychosocial and vocational impairment.

Circadian profiles in young people during the early stages of affective disorder

Although disturbances of the circadian system are strongly linked to affective disorders, no known studies have examined melatonin profiles in young people in early stages of illness. In this study, 44 patients with an affective disorder underwent clinical and neuropsychological assessments. They were then rated by a psychiatrist according to a clinical staging model and were categorized as having an 'attenuated syndrome' or an 'established disorder'. During the evening, salivary melatonin was sampled under dim light conditions over an 8-h interval and for each patient, the time of melatonin onset, total area under the curve and phase angle (difference between time of melatonin onset and time of habitual sleep onset) were computed. Results showed that there was no difference in the timing of melatonin onset across illness stages. However, area under the curve analyses showed that those patients with 'established disorders' had markedly reduced levels of melatonin secretion, and shorter phase angles, relative to those with 'attenuated syndromes'. These lower levels, in turn, were related to lower subjective sleepiness, and poorer performance on neuropsychological tests of verbal memory. Overall, these results suggest that for patients with established illness, dysfunction of the circadian system relates clearly to functional features and markers of underlying neurobiological change. Although the interpretation of these results would be greatly enhanced by control data, this work has important implications for the early delivery of chronobiological interventions in young people with affective disorders.

Distinct neurometabolic profiles are evident in the anterior cingulate of young people with major psychiatric disorders

Currently, there are no validated neurobiological methods for distinguishing different pathophysiological pathways in young patients presenting in the early phases of major psychiatric disorders. Hence, treatments are delivered simply on the basis of their possible effects on nonspecific symptom constructs such as depression, cognitive change or psychotic symptoms. In this study, the ratios (relative to creatine) of key metabolites (N-acetyl aspartate, myoinositol, glutamate and glutathione) were measured with proton magnetic resonance spectroscopy ((1)H-MRS) within the anterior cingulate cortex of 88 young persons presenting with major mood or psychotic symptoms. We derived empirically (using a cluster analytical technique) three subgroups of subjects on the basis of their patterns of in vivo brain biochemistry. The three subgroups were distinguished (from each other) by all the four metabolites, in particular, glutathione and glutamate. By contrast, the groups could not be distinguished by differences in terms of other demographic, functional or clinical measures. We propose that this (1)H-MRS-based subclassification system could be used as the basis for much more specific tests of novel intervention strategies (notably, antioxidant and glutamatergic therapies) early in the course of major psychiatric disorders.

Reduced temporal mismatch negativity in late-life depression: an event-related potential index of cognitive deficit and functional disability?

BACKGROUND

Depression in older people has been consistently linked with a variety of neurobiological brain changes. One measure of preattentive auditory processing, the mismatch negativity (MMN), has not been previously examined in late-life depression. This study examined MMN elicited by duration deviant stimuli in older people with lifetime depression, and explored its relationship with neuropsychological functioning and disability.

METHODS

Twenty-two older health-seeking patients (mean age=65.2 years) with lifetime major depressive disorder and twelve age and sex-matched control participants (mean age=64.6 years) completed detailed clinical and neuropsychological assessments and the WHO-DAS as a measure of disability. MMN amplitudes were elicited using a two-tone passive auditory oddball paradigm and measured at frontal (Fz), central (Cz) and temporal (left and right mastoid: M1 and M2, respectively) sites.

RESULTS

Patients with depression demonstrated reduced mean MMN amplitude at temporal (M1, t=3.1, p<0.01; M2, t=3.8, p<0.01), but not fronto-central sites. Reduced temporal MMN amplitudes did not relate to depressive symptom severity, but were associated with reduced semantic fluency and greater self-rated functional disability.

LIMITATIONS

The contribution of depressive symptom 'state' and medications on MMN need to be considered.

CONCLUSIONS

Reduced mean amplitudes of mastoid MMN in older patients with lifetime depression may reflect underlying brain changes. This preattentive marker relates to neuropsychological probes of frontotemporal circuits, and importantly, is associated with disability. Longitudinal analysis of MMN in this group will determine its predictive utility as a biomarker for ongoing cognitive decline and illness chronicity.

Frontal lobe changes occur early in the course of affective disorders in young people

BACKGROUND

More severe and persistent forms of affective disorders are accompanied by grey matter loss in key frontal and temporal structures. It is unclear whether such changes precede the onset of illness, occur early in the course or develop gradually with persistence or recurrence of illness. A total of 47 young people presenting with admixtures of depressive and psychotic symptoms were recruited from specialist early intervention services along with 33 age matched healthy control subjects. All participants underwent magnetic resonance imaging and patients were rated clinically as to current stage of illness. Twenty-three patients were identified as being at an early 'attenuated syndrome' stage, while the remaining were rated as having already reached the 'discrete disorder' or 'persistent or recurrent illness' stage. Contrasts were carried out between controls subjects and patients cohorts with attenuated syndromes and discrete disorders, separately.

RESULTS

The patients that were identified as having a discrete or persisting disorder demonstrated decreased grey matter volumes within distributed frontal brain regions when contrasted to both the control subjects as well as those patients in the attenuated syndrome stage. Overall, patients who were diagnosed as more advanced in terms of the clinical stage of their illness, exhibited the greatest grey matter volume loss of all groups.

CONCLUSIONS

This study suggests that, in terms of frontal grey matter changes, a major transition point may occur in the course of affective illness between early attenuated syndromes and later discrete illness stages.

How does social functioning in the early stages of psychosis relate to depression and social anxiety?

AIMS

The study aims to compare social functioning in young people considered to be at risk of psychosis with those meeting criteria for first episode psychosis (FEP) and controls, and to determine the association between social functioning and positive and negative symptoms, depressive symptoms, and social anxiety.

METHODS

This study examined social functioning in 20 individuals at risk of psychosis, 20 FEP patients and 20 healthy controls. Social functioning was measured using the Social Functioning Scale and World Health Organization Disability Assessment Scale. Psychiatric variables were also measured using the Comprehensive Assessment of At-Risk Mental States, the Brief Psychiatric Rating Scale, the Brief Social Phobia Scale, and the Depression Anxiety and Stress Scale.

RESULTS

At-risk individuals had comparable social deficits to the FEP group, and both patient groups had significantly poorer social functioning than controls. Importantly, social functioning was most strongly associated with depressive and social anxiety symptoms and to a lesser extent with positive symptoms. However, negative symptoms did not appear to relate to social functioning.

CONCLUSION

Social functioning impairments precede the onset of full-threshold psychosis and may therefore be a significant marker for the illness. Additionally, associated psychiatric symptoms such as depression and social anxiety may provide an avenue for early interventions of social functioning deficits in psychosis.

A randomized controlled trial investigation of a non-stimulant in attention deficit hyperactivity disorder (ACTION): rationale and design

BACKGROUND

The ACTION study (Attention deficit hyperactivity disorder Controlled Trial Investigation Of a Non-stimulant) is a multi-center, double-blind, randomized cross-over trial of the non-stimulant medication, Atomoxetine, in children and adolescents with attention deficit hyperactivity disorder (ADHD). The primary aims are to examine the efficacy of atomoxetine for improving cognition and emotional function in ADHD and whether any improvements in these outcomes are more pronounced in participants with comorbid anxiety; and to determine if changes in these outcomes after atomoxetine are more reliable than changes in diagnostic symptoms of ADHD. This manuscript will describe the methodology and rationale for the ACTION study.

METHODS

Children and adolescents aged 6 - 17 y with ADHD will be enrolled. Clinical interview and validated scales will be used to confirm diagnosis and screen for exclusion criteria, which include concurrent stimulant use, and comorbid psychiatric or neurological conditions other than anxiety. Three assessment sessions will be conducted over the 13-week study period: Session 1 (Baseline, pre-treatment), Session 2 (six weeks, atomoxetine or placebo), and Session 3 (13 weeks, cross-over after one-week washout period). The standardized touch-screen battery, "IntegNeuro™", will be used to assess cognitive and emotional function. The primary measure of response will be symptom ratings, while quality of life will be a secondary outcome. Logistic regression will be used to determine predictors of treatment response, while repeated measures of analysis will determine any differences in effect of atomoxetine and placebo.

RESULTS

The methodology for the ACTION study has been detailed.

CONCLUSIONS

The ACTION study is the first controlled trial to investigate the efficacy of atomoxetine using objective cognitive and emotional function markers, and whether these objective measures predict outcomes with atomoxetine in ADHD with and without comorbid anxiety. First enrollment was in March 2008. The outcomes of this study will be a significant step towards a 'personalized medicine' (and therefore a more efficient) approach to ADHD treatment.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry ANZCTRN12607000535471.

Chronic cannabis users show altered neurophysiological functioning on Stroop task conflict resolution

RATIONALE

Chronic cannabis use has been related to deficits in cognition (particularly memory) and the normal functioning of brain structures sensitive to cannabinoids. There is increasing evidence that conflict monitoring and resolution processes (i.e. the ability to detect and respond to change) may be affected.

OBJECTIVES

This study examined the ability to inhibit an automatic reading response in order to activate a more difficult naming response (i.e. conflict resolution) in a variant of the discrete trial Stroop colour-naming task.

METHODS

Event-related brain potentials to neutral, congruent and incongruent trials were compared between 21 cannabis users (mean 16.4 years of near daily use) in the unintoxicated state and 19 non-using controls.

RESULTS

Cannabis users showed increased errors on colour-incongruent trials (e.g. "RED" printed in blue ink) but no performance differences from controls on colour congruent (e.g. "RED" printed in red ink) or neutral trials (e.g. "*****" printed in green ink). Poorer incongruent trial performance was predicted by an earlier age of onset of regular cannabis use. Users showed altered expression of a late sustained potential related to conflict resolution, evident by opposite patterns of activity between trial types at midline and central sites, and altered relationships between neurophysiological and behavioural outcome measures not evident in the control group.

CONCLUSIONS

These findings indicate that chronic use of cannabis may impair the brain's ability to respond optimally in the presence of events that require conflict resolution and hold implications for the ability to refrain from substance misuse and/or maintain substance abstention behaviours.

Impaired MMN/P3a complex in first-episode psychosis: cognitive and psychosocial associations

Mismatch negativity (MMN) is a neurophysiological indicator of the brain's ability to extract relevant information from an irrelevant background. The P3a orienting response often accompanies MMN in deviance detection paradigms. Both MMN and P3a have been described as reliable biomarkers of schizophrenia. MMN/P3a impairments are associated with deficits in verbal memory and attentional switching, reflecting dysfunctions in the temporal and frontal systems, respectively. It remains unresolved whether MMN/P3a are robust biomarkers of psychosis in first-episode patients. Thirty-four young people (18 to 30years) were assessed in this study; 17 first-episode psychosis (FEP) patients were compared to 17 healthy controls. To elicit MMN/P3a, a two-tone passive auditory oddball paradigm with 8% duration deviants was used; event-related potentials were recorded at frontal, central and temporal (mastoid) sites. Neuropsychological assessments included processing speed, attentional switching, simple attention, and verbal learning and memory. Social functioning and quality of life measures were also obtained. The FEP group showed significantly reduced MMN amplitudes compared to controls. The FEP group also showed significantly reduced P3a amplitudes at frontal and central sites compared with controls. As expected, the FEP group also showed significant deficits in attention and verbal learning/memory. Correlational analyses found strong associations between fronto-central MMN/P3a peak amplitude and cognitive/psychosocial functioning. This study provides evidence of early neurobiological markers in young people with FEP. These findings suggest that MMN/P3a impairments are present at early stages of psychosis and that fundamental pre-attentive/deviance detection deficits may mark the beginning of progressive underlying changes with illness onset. Such deficits in FEP appear to have important links with higher-order cognitive and psychosocial functioning.

Impaired verbal memory in young adults with unipolar and bipolar depression

AIM

Early stages of severe mood disorders may be accompanied by neurocognitive changes. Specifically, deficits in verbal memory have been linked to depression in young people. This study examined whether young adults with unipolar compared with bipolar depression showed similar neurocognitive deficits.

METHODS

A total of 57 young adults (16-32 years) were assessed in this study. Twenty with unipolar and 20 with bipolar depression, all currently depressed, were compared with 17 healthy controls. Neuropsychological assessment included psychomotor speed, attention for routine mental operations, attentional switching, executive control and verbal learning and memory.

RESULTS

Both unipolar and bipolar subjects showed significant impairments in verbal memory and attentional switching compared with controls. Both mood disorder groups showed no impairments in psychomotor speed, attention for routine mental operations and executive control. Effects size calculations show that the unipolar and bipolar groups do not differ from each other across a range of neurocognitive measures.

CONCLUSION

Neurocognitive deficits in young adults with current depressive syndromes appear to differ from those typically seen in older patients. In early adulthood, both unipolar and bipolar depression may be distinguished by poor verbal memory, despite intact speed of processing, attention and executive functions. This study suggests that there is utility in neuropsychological testing for young adults in the early stages of severe mood disorders. In order to prevent neurobiological changes inherent to the disease, pharmacological and non-pharmacological interventions that target verbal memory deficits may be optimally delivered early in the disease course.