Neurocognitive allied phenotypes for schizophrenia and bipolar disorder

Psychiatric disorders are genetically complex and represent the end product of multiple biological and social factors. Links between genes and disorder-related abnormalities can be effectively captured via assessment of phenotypes that are both associated with genetic effects and potentially contributory to behavioral abnormalities. Identifying intermediate or allied phenotypes as a strategy for clarifying genetic contributions to disorders has been successful in other areas of medicine and is a promising strategy for identifying susceptibility genes in complex psychiatric disorders. There is growing evidence that schizophrenia and bipolar disorder, rather than being wholly distinct disorders, share genetic risk at several loci. Further, there is growing evidence of similarity in the pattern of cognitive and neurobiological deficits in these groups, which may be the result of the effects of these common genetic factors. This review was undertaken to identify patterns of performance on neurocognitive and affective tasks across probands with schizophrenia and bipolar disorder as well as unaffected family members, which warrant further investigation as potential intermediate trait markers. Available evidence indicates that measures of attention regulation, working memory, episodic memory, and emotion processing offer potential for identifying shared and illness-specific allied neurocognitive phenotypes for schizophrenia and bipolar disorder. However, very few studies have evaluated neurocognitive dimensions in bipolar probands or their unaffected relatives, and much work in this area is needed.

Type and duration of subsyndromal symptoms in youth with bipolar I disorder prior to their first manic episode

OBJECTIVES

The aim of the present study was to systematically evaluate the prodrome to mania in youth.

METHODS

New-onset/worsening symptoms/signs of ≥ moderate severity preceding first mania were systematically assessed in 52 youth (16.2 ± 2.8 years) with a research diagnosis of bipolar I disorder (BD-I). Youth and/or caregivers underwent semi-structured interviews, using the Bipolar Prodrome Symptom Scale-Retrospective.

RESULTS

The mania prodrome was reported to start gradually in most youth (88.5%), with either slow (59.6%) or rapid (28.8%) deterioration, while a rapid-onset-and-deterioration prodrome was rare (11.5%). The manic prodrome, conservatively defined as requiring ≥ 3 symptoms, lasted 10.3 ± 14.4 months [95% confidence interval (CI): 6.3-14.4], being present for ≥ 4 months in 65.4% of subjects. Among prodromal symptoms reported in ≥ 50% of youth, three were subthreshold manic in nature (irritability: 61.5%, racing thoughts: 59.6%, increased energy/activity: 50.0%), two were nonspecific (decreased school/work functioning: 65.4%, mood swings/lability: 57.7%), and one each was depressive (depressed mood: 53.8%) or subthreshold manic/depressive (inattention: 51.9%). A decreasing number of youth had ≥ 1 (84.6%), ≥ 2 (48.1%), or ≥ 3 (26.9%) 'specific' subthreshold mania symptoms (i.e., elation, grandiosity, decreased need for sleep, racing thoughts, or hypersexuality), lasting 9.5 ± 14.9 months (95% CI: 5.0-14.0), 3.5 ± 3.5 months (95% CI: 2.0-4.9), and 3.0 ± 3.2 months (95% CI: 1.0-5.0) for ≥ 1, ≥ 2, or ≥ 3 specific symptoms, respectively.

CONCLUSIONS

In youth with BD-I, a relatively long, predominantly slow-onset mania prodrome appears to be common, including subthreshold manic and depressive psychopathology symptoms. This suggests that early clinical identification and intervention may be feasible in bipolar disorder. Identifying biological markers associated with clinical symptoms of impending mania may help to increase chances for early detection and prevention before full mania.

Child- and family-focused cognitive-behavioral therapy for pediatric bipolar disorder: a randomized clinical trial

OBJECTIVE

Previous studies have found that family-based psychosocial treatments are effective adjuncts to pharmacotherapy among adults and adolescents with bipolar disorder (BD). The objective of this study was to compare the efficacy of adjunctive child- and family-focused cognitive-behavioral therapy (CFF-CBT) to psychotherapy as usual (control) for mood symptom severity and global functioning in children with BD.

METHOD

Sixty-nine youth, aged 7 to 13 years (mean = 9.19, SD = 1.61) with DSM-IV-TR bipolar I, II, or not otherwise specified (NOS) disorder were randomly assigned to CFF-CBT or control groups. Both treatments consisted of 12 weekly sessions followed by 6 monthly booster sessions delivered over a total of 9 months. Independent evaluators assessed participants at baseline, week 4, week 8, week 12 (posttreatment), and week 39 (6-month follow-up).

RESULTS

Participants in CFF-CBT attended more sessions, were less likely to drop out, and reported greater satisfaction with treatment than controls. CFF-CBT demonstrated efficacy compared to the control treatment in reducing parent-reported mania at posttreatment and depression symptoms at posttreatment and follow-up. Global functioning did not differ at posttreatment but was higher among CFF-CBT participants at follow-up.

CONCLUSION

CFF-CBT may be efficacious in reducing acute mood symptoms and improving long-term psychosocial functioning among children with BD.

Microstructural abnormalities of white matter differentiate pediatric and adult-onset bipolar disorder

OBJECTIVES

White-matter microstructure, known to undergo significant developmental transformation, is abnormal in bipolar disorder (BD). Available evidence suggests that white-matter deviation may be more pronounced in pediatric than adult-onset BD. The present study aimed to examine how white-matter microstructure deviates from a typical maturational trajectory in BD.

METHODS

Fractional anisotropy (FA) was measured in 35 individuals presenting with first episode BD (type I) and 46 healthy controls (HC) (aged 9-42) using diffusion tensor imaging (DTI). Patients were medication free and close to illness onset at the time of the DTI scans. Tract-based spatial statistics were used to examine the center of white-matter tracts, and FA was extracted from nine tracts of interest. Axial, radial, and mean diffusivity were examined in post-hoc analyses.

RESULTS

The left anterior limb of the internal capsule (ALIC) showed significantly lower FA in pediatric than adult-onset BD. The lower FA in BD was due primarily to greater radial, rather than decreased axial, diffusivity.

CONCLUSIONS

The ALIC connects the frontal lobes with archistriatum, thalamus, and medial temporal regions, and alteration in these pathways may contribute to mood dysregulation in BD. Abnormalities in this pathway appear to be associated with an earlier onset of illness and thus may reflect a greater susceptibility to illness.

Post-acute effectiveness of lithium in pediatric bipolar I disorder

OBJECTIVE

This study examined the long-term effectiveness of lithium for the treatment of pediatric bipolar disorder within the context of combination mood stabilizer therapy for refractory mania and pharmacological treatment of comorbid psychiatric conditions.

METHODS

Outpatients, ages 7-17 years, meeting American Psychiatric Association, diagnostic and statistical manual of mental disorders, 4th ed. (DSM-IV) diagnostic criteria for bipolar disorder I (BP-I) (manic or mixed) who demonstrated at least a partial response to 8 weeks of open-label treatment with lithium (phase I) were eligible to receive open-label lithium for an additional 16 weeks (phase II). Up to two adjunctive medications could be prescribed to patients experiencing residual symptoms of mania or comorbid psychiatric conditions, following a standardized algorithm.

RESULTS

Forty-one patients received continued open-label long-term treatment with lithium for a mean of 14.9 (3.0) weeks during phase II. The mean weight-adjusted total daily dose at end of phase II was 27.8 (6.7) mg/kg/day, with an average lithium concentration of 1.0 (0.3) mEq/L. Twenty-five of the 41 patients (60.9%) were prescribed adjunctive psychotropic medications for residual symptoms. The most frequent indications for adjunctive medications were refractory mania (n=13; 31.7%) and attention-deficit/hyperactivity disorder (ADHD) (n=15; 36.6%). At the end of this phase 28 (68.3%) patients met a priori criteria for response (≥50% reduction from phase I baseline in young mania rating scale [YMRS] summary score and a clinical global impressions-improvement [CGI-I] score of 1 or 2), with 22 (53.7%) considered to be in remission (YMRS summary score≤12 and CGI-severity score of 1 or 2). These data suggest that patients who initially responded to lithium maintained mood stabilization during continuation treatment, but partial responders did not experience further improvement during Phase II, despite the opportunity to receive adjunctive medications. The most commonly reported (≥20%) adverse events associated with lithium treatment were vomiting, headache, abdominal pain, and tremor.

CONCLUSIONS

Lithium may be a safe and effective longer-term treatment for patients with pediatric bipolar disorder who respond to acute treatment with lithium. Partial responders to acute lithium did not appear to experience substantial symptom improvement during the continuation phase, despite the possibility that adjunctive medications could be prescribed.

The Collaborative Lithium Trials (CoLT): specific aims, methods, and implementation

BACKGROUND

Lithium is a benchmark treatment for bipolar illness in adults. However, there has been relatively little methodologically stringent research regarding the use of lithium in youth suffering from bipolarity.

METHODS

Under the auspices of the Best Pharmaceuticals for Children Act (BPCA), a Written Request (WR) pertaining to the study of lithium in pediatric mania was issued by the United States Food and Drug Administration (FDA) to the National Institute of Child Health and Human Development (NICHD) in 2004. Accordingly, the NICHD issued a Request for Proposals (RFP) soliciting submissions to pursue this research. Subsequently, the NICHD awarded a contract to a group of investigators in order to conduct these studies.

RESULTS

The Collaborative Lithium Trials (CoLT) investigators, the BPCA-Coordinating Center, and the NICHD developed protocols to provide data that will: (1) establish evidence-based dosing strategies for lithium; (2) characterize the pharmacokinetics and biodisposition of lithium; (3) examine the acute efficacy of lithium in pediatric bipolarity; (4) investigate the long-term effectiveness of lithium treatment; and (5) characterize the short- and long-term safety of lithium. By undertaking two multi-phase trials rather than multiple single-phase studies (as was described in the WR), the feasibility of the research to be undertaken was enhanced while ensuring all the data outlined in the WR would be obtained. The first study consists of: (1) an 8-week open-label, randomized, escalating dose Pharmacokinetic Phase; (2) a 16-week Long-Term Effectiveness Phase; (3) a 28-week double-blind Discontinuation Phase; and (4) an 8-week open-label Restabilization Phase. The second study consists of: (1) an 8-week, double-blind, parallel-group, placebo-controlled Efficacy Phase; (2) an open-label Long-Term Effectiveness lasting either 16 or 24 weeks (depending upon blinded treatment assignment during the Efficacy Phase); (3) a 28-week double-blind Discontinuation Phase; and (4) an 8-week open-label Restabilization Phase. In December of 2006, enrollment into the first of these studies began across seven sites.

CONCLUSION

These innovative studies will not only provide data to inform the labeling of lithium in children and adolescents with bipolar disorder, but will also enhance clinical decision-making regarding the use of lithium treatment in pediatric bipolar illness.

TRIAL REGISTRATION

NCT00442039.

Dosing strategies for lithium monotherapy in children and adolescents with bipolar I disorder

OBJECTIVE

The primary goal of this exploratory study was to obtain data that could lead to evidence-based dosing strategies for lithium in children and adolescents suffering from bipolar I disorder.

METHODS

Outpatients aged 7-17 years meeting Diagnostic and Statistical Manual of Mental Disorders, 4th edition, diagnostic criteria for bipolar I disorder (manic or mixed) were eligible for 8 weeks of open label treatment with lithium in one of three dosing arms. In Arm I, participants began treatment at a dose of 300 mg of lithium twice daily. The starting dose of lithium in Arms II and III was 300 mg thrice daily. Patients in Arms I and II could have their dose increased by 300 mg/day, depending on clinical response, at weekly visits. Patients in Arm III also had mid-week telephone interviews after which they could also have their dose of lithium increased by 300 mg per day. Youths weighing <30 kg were automatically assigned to Arm I, whereas youths weighing ≥30 kg were randomly assigned to Arm I, II, or III. Randomization was balanced by age (7-11 years, 12-17 years) and sex in approximately equal numbers. A priori response criteria were defined as a Clinical Global Impressions-Improvement scale score of ≤ 2 and a 50% decrease from baseline on the Young Mania Rating Scale.

RESULTS

Of the 61 youths [32 males (52.5%)] who received open-label lithium, 60 youths completed at least 1 week of treatment and returned for a postbaseline assessment. Most patients had a ≥ 50% improvement in Young Mania Rating Scale score, and more than half of the patients (58%) achieved response. Overall, lithium was well tolerated. All three treatment arms had similar effectiveness, side effect profiles, and tolerability of lithium.

CONCLUSIONS

On the basis of these results, a dosing strategy in which pediatric patients begin lithium at a dose of 300 mg thrice daily (with an additional 300 mg increase during the first week), followed by 300 mg weekly increases until a priori stopping criteria are met, will be used in an upcoming randomized, placebo-controlled trial.

Lithium for the Maintenance Treatment of Bipolar I Disorder: A Double-Blind, Placebo-Controlled Discontinuation Study

OBJECTIVE

This study examined the role of lithium in the maintenance treatment of pediatric patients with bipolar I disorder (BP-I).

METHOD

Participants aged 7 to 17 years who presented with a manic or mixed episode received 24 weeks of lithium treatment in one of two multiphase studies, the Collaborative Lithium Trials (CoLT 1 and CoLT 2). Responders were randomized to continue lithium or to be cross-titrated to placebo for up to 28 weeks. The primary outcome measure was relative risk of study discontinuation for any reason.

RESULTS

A Cox regression analysis found that those who continued treatment with lithium (n = 17) had a lower hazard ratio compared to those who received placebo (n = 14) (p = .015)]. The vast majority of discontinuations were due to mood symptom exacerbations, with most of these occurring in the placebo-treated group. Discontinuation for other reasons occurred at similarly low rates across both group. Most adverse events were mild to moderate in severity, and only one study participant was discontinued from the trial owing to a serious adverse event (aggression). There was no statistically significant difference with respect to weight gain in participants receiving lithium compared to those receiving placebo.

CONCLUSION

This randomized, double-blind, placebo-controlled Discontinuation Trial builds support for the role of lithium as a maintenance treatment in pediatric patients with bipolar disorder and for the safety and tolerability of 28 weeks of maintenance lithium treatment.

CLINICAL TRIAL REGISTRATION INFORMATION

Lithium for the Treatment of Pediatric Mania; https://clinicaltrials.gov/; NCT00442039 (CoLT 1). Safety and Efficacy Study of Lithium for the Treatment of Pediatric Mania; https://clinicaltrials.gov/; NCT01166425 (CoLT 2).

Psychosocial intervention for pediatric bipolar disorder: current and future directions

Pediatric bipolar disorder (PBD) affects approximately 2% of the population and disrupts mood regulation, psychosocial functioning and quality of life among affected youths and families. Given the significant psychosocial impairment and poor long-term prognosis associated with PBD, psychosocial intervention is considered to be an essential component of a multimodal treatment approach. This relatively young field of research has witnessed significant growth in the evidence base for psychosocial treatments targeting youths in the past decade, particularly family-based interventions grounded in a biopsychosocial framework. This article reviews existing empirically supported interventions for children and adolescents with PBD. Common elements of successful interventions are identified, and future research directions to address current limitations in the field and advance understanding of treatment for PBD are discussed.

A practical guide to using ratings of depression and anxiety in child psychiatric practice

The objective of this paper is to provide pragmatic information on commonly used rating scales of depression and anxiety disorders with established psychometric properties. A comprehensive Medline search on the rating scales of depression and anxiety was conducted. Relevant research findings were further synthesized where possible, with the information on clinical use of the scales from manuals. Research findings replicating original studies, strengths, weaknesses, and scoring information were summarized for each scale, and psychometric properties were tabulated. Several rating scales are available for screening, determining the severity, as well as estimating treatment effects in depression and anxiety. It is prudent to use more than two scales, especially a combination of self-rating scale and a clinician rating scale. It is recommended that the depression and anxiety scales are used in concert to aid in differentiating these two disorders. Several new and improved scales are available, although they await further replication.

Efficacy of omega-3 fatty acids in mood disorders - a systematic review and metaanalysis

OBJECTIVES

Existing efficacy trials of Omega-3 (omega-3) fatty acids in mood disorders have yielded inconsistent results. The current paper is an effort to provide a systematic review and meta-analysis to evaluate efficacy of omega-3 fatty acids in treatment of mood disorders.

DESIGN

We searched Medline, Embase, PsychInfo, and the Cochrane Controlled Trials registry up to June 2008 for randomized trials investigating efficacy of omega-3 fatty acids in mood disorders.We conducted random effects meta-analyses.We used the I2 statistic to quantify between-study inconsistency, and conducted pre-specified subgroup analyses to explore potential explanations for inconsistency.

OBSERVATIONS

We included 21 trials in our systematic review and found 13 trials to be eligible for meta-analysis. The pooled standardized mean difference in depressed mood states (n = 554 in 12 trials) was -0.47 (95% CI:-0.92,-0.02; I2 = 82.7; p = 0.07) and in manic mood states (n = 126 in 4 trials) was 0.22 (95% CI: -0.21, 0.65; I2 = 40.5; p = 0.31).We did not identify any treatment- subgroup interaction across forms of omega-3 fatty acids preparations (P = 0.99) or patient diagnosis (bipolar vs. unipolar depressive disorder; P = 0.96); there was a significant correlation between omega-3 fatty acids dose and treatment effect on depressive symptoms (r = 0.5, p = 0.04), but not on manic symptoms (P = 0.3).

CONCLUSIONS

The available evidence suggests that omega-3 fatty acids are a potential treatment of depressive disorders, but not mania. The unexplained between-study inconsistency and imprecision of the pooled estimates mitigate this suggestion. Large randomized placebo-controlled trials are needed to better estimate the value of this intervention for patients with depression.

Emerging biosignature of brain function and intervention in pediatric bipolar disorder

Pediatric bipolar disorder (PBD) is a complex illness with a chronic course, requiring multiple medications over the longitudinal course of illness, with limited recovery and high relapse rate. Beyond the placebo controlled trials of monotherapy, there is an increased need to understand how each medication influences regions of affective and cognitive circuitry function by normalization or deployment of alternative circuitry regions. Functional studies are beginning to unravel the improved function in the fronto-limbic and fronto-temporal affective circuitry, and based on the paradigm administered, also in the interfacing cognitive fronto-striato-temporo-parietal regions. Treatment studies illustrated a pattern of improvement in functional activity consistently among the affective ventrolateral and medial prefrontal regions, and variably in the cognitive dorsolateral prefrontal cortex. While there is decreased activity in amygdala with treatment for mania or depression among patients with PBD, there appears to be residual increased amygdala activity regardless of response, relative to healthy controls, suggesting a trait-like abnormality. Parallel biochemical abnormalities in magnetic resonance spectroscopic studies and fronto-limbic activity in magnetic resonance imaging studies of brain function at baseline provide maiden data on predicting outcome. This preliminary cohort of studies that probed the hypothesized circuitries underlying specific symptom constructs, coupled with futuristic paradigms and analytic methods, serve as a guidepost to generate the next generation of studies and build on the emerging biosignature towards specific treatment targets for personalized medicine in PBD.

Development of a Korean Version of the Child Mania Rating Scale: Korean Validity and Reliability Study

OBJECTIVE

Clinical rating scales are essential in psychiatry. The Young Mania Rating Scale is the gold standard for assessing mania. However, increased attention to pediatric bipolar disorder has led to the development of the Child Mania Rating Scale (CMRS), which is a parent-reported rating scale designed to assess mania in children and adolescents. This study aimed to translate the CMRS into Korean and assess the validity and reliability of the Korean version of the CMRS (K-CMRS).

METHODS

The original English version of the CMRS has been translated into Korean. We enrolled 33 patients with bipolar disorder and 26 patients with attention-deficit hyperactivity disorder (ADHD). All participants were evaluated using the translated K-CMRS, Mood Disorder Questionnaire (MDQ), and ADHD Rating Scale.

RESULTS

The Cronbach's α was 0.907. Correlation analyses between K-CMRS and MDQ scores yielded significant positive correlations (r=0.529, p=0.009). However, the factor analysis was unsuccessful. The total K-CMRS scores of bipolar disorder and ADHD patients were compared. However, the differences were not statistically significant.

CONCLUSION

The K-CMRS showed good internal consistency and reliability. The correlation between the K-CMRS and MDQ scores verifies its validity. The K-CMRS was designed to assess and score manic symptoms in children and adolescents but had difficulties in differentiating between bipolar disorder and ADHD. It is a valuable tool for evaluating the presence and severity of manic symptoms in pediatric patients with bipolar disorder.

Mechanistic comparisons of functional domains across pediatric and adult bipolar disorder highlight similarities, as well as differences, influenced by the developing brain

Recent neuroimaging studies have uncovered much about the specific neural deficits in adult bipolar disorder (ABD), but despite promising results, neuroimaging research for pediatric bipolar disorder (PBD) is still developing. The neuroimaging literature is highly heterogeneous, varying in the paradigms used and in participants' mood states and medication status. Despite this variability, several dominant patterns emerge. In response to emotional stimuli, both ABD and PBD show limbic hyperactivity coupled with hypoactivity in ventral prefrontal emotion regulation systems. This pattern occurred most robustly in response to negative incidental stimuli and was especially apparent in manic PBD. ABD showed more variability in ventral prefrontal activity, possibly due to maturational and medication factors. On numerous cognitive paradigms, PBD showed dorsal prefrontal hypoactivity linked to ventral dysfunction, whereas ABD showed compensatory frontal, parietal, and temporal activity with paradigm-specific variations. In emotion-cognition interaction paradigms, patients show dysregulation in regions interfacing between cognitive and emotional brain systems (e.g., ventral prefrontal and cingulate cortices), which expend extra effort to process emotional stimuli effectively and recruit additional posterior attention systems to cope with affective instability. In addition, novel functional connectivity techniques have uncovered connectivity deficits between frontal and limbic regions in ABD and PBD at rest and during active emotional and cognitive tasks. Finally, the neuroimaging literature currently lacks cross-sectional studies comparing PBD with ABD and longitudinal studies following children and adolescents with BD into adulthood. Such studies would provide important insights into patients' prognosis and would determine targets for early interventions in the evolving illness diathesis.