Clinical predictors of acute response with olanzapine in psychotic mood disorders

Applied Machine Learning Method to Predict Children With ADHD Using Prefrontal Cortex Activity: A Multicenter Study in Japan

Objective: To establish valid, objective biomarkers for ADHD using machine learning. Method: Machine learning was used to predict disorder severity from new brain function data, using a support vector machine (SVM). A multicenter approach was used to collect data for machine learning training, including behavioral and physiological indicators, age, and reverse Stroop task (RST) data from 108 children with ADHD and 108 typically developing (TD) children. Near-infrared spectroscopy (NIRS) was used to quantify change in prefrontal cortex oxygenated hemoglobin during RST. Verification data were from 62 children with ADHD and 37 TD children from six facilities in Japan. Results: The SVM general performance results showed sensitivity of 88.71%, specificity of 83.78%, and an overall discrimination rate of 86.25%. Conclusion: A SVM using an objective index from RST may be useful as an auxiliary biomarker for diagnosis for children with ADHD.

Validity and reliability of the Dundee difficult times of the day scale in Chinese children and adolescents with attention-deficit/hyperactivity disorder

METHODS

A cross-sectional study enrolled 200 children and adolescents with attention-deficit/hyperactivity disorder visiting four Chinese tertiary care psychiatric clinics to assess the validity and reliability of the Dundee difficult times of the day scale (D-DTODS), using the Weiss functional impairment rating scale for parents form (WFIRS-P) and the Swanson, Nolan and Pelham, version IV 26-item teacher and parent rating scale (SNAP-IV-26).

RESULTS

The calculated Cronbach's-α for the D-DTODS total score was 0.793. The calculated Spearman's correlation coefficients for D-DTODS versus WFRIS-P and Swanson, Nolan and Pelham, version IV 26-item teacher and parent rating scale (SNAP-IV-26) were 0.425 (p < 0.01) and 0.452 (p < 0.001), respectively.

CONCLUSION

The D-DTODS was worth future test-retest confirmation regarding reliability and validity for assessing functional impairment associated with attention-deficit/hyperactivity disorder across different time periods of the day in Chinese children and adolescents.

How Good Am I? Implicit and Explicit Self-Esteem as a Function of Perceived Parenting Styles Among Children With ADHD

OBJECTIVE

To investigate implicit and explicit self-esteem and academic self-evaluation among children with ADHD as a function of parenting styles, namely, authoritarian, authoritative and permissive parenting.

METHOD

Participants included 43 children with ADHD and 35 non-ADHD controls who filled out self-concept and perceived parenting style questionnaires. They also took an Implicit Association Test (IAT) that measured unacknowledged self-esteem.

RESULTS

Lower self-esteem was found among children with ADHD than among controls, with stronger effect on the implicit level. Perceived authoritarian parenting was related to lower implicit self-esteem among children with ADHD. Higher self-esteem was found in the authoritative than in the permissive parenting groups in the non-ADHD control group but not among children with ADHD.

CONCLUSION

The role of parental support versus authoritarian parenting in terms of implicit self-esteem points to the importance of promoting responsiveness strategies among parents in the treatment of children with ADHD.

Genome-wide association study reveals novel genetic locus associated with intra-individual variability in response time

Intra-individual response time variability (IIRTV) is proposed as a viable endophenotype for many psychiatric disorders, particularly attention-deficit hyperactivity disorder (ADHD). Here we assessed whether IIRTV was associated with common DNA variation genome-wide and whether IIRTV mediated the relationship between any associated loci and self-reported ADHD symptoms. A final data set from 857 Australian young adults (489 females and 368 males; Mage = 22.14 years, SDage = 4.82 years) who completed five response time tasks and self-reported symptoms of ADHD using the Conners' Adult ADHD Rating Scale was used. Principal components analysis (PCA) on these response time measures (standard deviation of reaction times and the intra-individual coefficient of variation) produced two variability factors (labelled response selection and selective attention). To understand the genetic drivers of IIRTV we performed a genome-wide association analysis (GWAS) on these PCA-derived indices of IIRTV. For the selective attention variability factor, we identified one single-nucleotide polymorphism (SNP) attaining genome-wide significance; rs62182100 in the HDAC4 gene located on chromosome 2q37. A bootstrapping mediation analysis demonstrated that the selective attention variability factor mediated the relationship between rs62182100 and self-reported ADHD symptoms. Our findings provide the first evidence of a genome-wide significant SNP association with IIRTV and support the potential utility of IIRTV as a valid endophenotype for ADHD symptoms. However, limitations of this study suggest that these observations should be interpreted with caution until replication samples become available.

Olanzapine: Psychopharmacology, Clinical Efficacy, and Adverse Effects

Olanzapine is an atypical antipsychotic that has a pharmacological profile similar that of clozapine. It is biotransformed by hepatic enzymes and can be dosed on a once-daily basis. In large, double-blind, placebo-controlled trials, olanzapine was shown to be efficacious in the treatment of schizophrenia relative to placebo. Many trials showed superior efficacy to haloperidol, especially against negative symptoms. Olanzapine is FDA-approved for the treatment of psychotic disorders, though data suggest possible use in depression, bipolar disorder, psychogenic polydipsia, and developmental disabilities. Olanzap-ine appears to be well-tolerated. Commonly reported adverse effects include orthostatic hypotension, sedation, hepatic transaminase elevations, weight gain, headache, agitation, dizziness, and constipation. The incidence of extrapyramidal symptoms and tardive dyskinesia is low. Few drug interactions have been reported. The recommended starting dose is 10 mg once daily. One trial indicated that the higher cost of this agent might be offset by a reduction in overall hospitalization costs.

Oppositional Defiant Disorder Is Better Conceptualized as a Disorder of Emotional Regulation

OBJECTIVE

It has been reported that Oppositional Defiant Disorder (ODD) can be differentiated into distinct subtypes associated with different outcomes in adulthood. We examined whether ODD is conceptually independent and coherent, and whether ODD and Conduct Disorder (CD) are expressions of the same core deficit.

METHOD

The data come from a sample of 4,380 children for whom SNAP rating scales were available. Parallel analysis was performed on the eight-item ODD diagnostic items and on the SNAP-90 scale. These were factor analyzed and the components were correlated.

RESULTS

ODD has one underlying factor, whereas the parent-rated SNAP has nine underlying factors. ODD items grouped together with emotional lability and irritability items, which did not group with CD. Confirmatory factor analysis supported the separation of ODD and CD but not ODD and emotion dysregulation.

CONCLUSION

The expanded ODD factor more likely captures a disorder of emotion regulation, rather than a disruptive behavior disorder.

Quantitative EEG in Children and Adults With Attention Deficit Hyperactivity Disorder: Comparison of Absolute and Relative Power Spectra and Theta/Beta Ratio

In recent decades, resting state electroencephalographic (EEG) measures have been widely used to document underlying neurophysiological dysfunction in attention deficit hyperactivity disorder (ADHD). Although most EEG studies focus on children, there is a growing interest in adults with ADHD too. The aim of this study was to objectively assess and compare the absolute and relative EEG power as well as the theta/beta ratio in children and adults with ADHD. The evaluated sample comprised 30 male children and 30 male adults with ADHD diagnosed according to DSM-IV criteria. They were compared with 30 boys and 30 male adults matched by age. The mean age (±SD) of the children's group was 9 (±2.44) years and the adult group 35.8 (±8.65) years. EEG was recorded during an eyes-open condition. Spectral analysis of absolute (μV²) and relative power (%) was carried out for 4 frequency bands: delta (2-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), and beta (13-21 Hz). The findings obtained for ADHD children are increased absolute power of slow waves (theta and delta), whereas adults exhibited no differences compared with normal subjects. For the relative power spectra there were no differences between the ADHD and control groups. Across groups, the children showed greater relative power than the adults in the delta and theta bands, but for the higher frequency bands (alpha and beta) the adults showed more relative power than children. Only ADHD children showed greater theta/beta ratio compared to the normal group. Classification analysis showed that ADHD children could be differentiated from the control group by the absolute theta values and theta/beta ratio at Cz, but this was not the case with ADHD adults. The question that should be further explored is if these differences are mainly due to maturation processes or if there is a core difference in cortical arousal between ADHD children and adults.

Glutamatergic and GABAergic gene sets in attention-deficit/hyperactivity disorder: association to overlapping traits in ADHD and autism

Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD) often co-occur. Both are highly heritable; however, it has been difficult to discover genetic risk variants. Glutamate and GABA are main excitatory and inhibitory neurotransmitters in the brain; their balance is essential for proper brain development and functioning. In this study we investigated the role of glutamate and GABA genetics in ADHD severity, autism symptom severity and inhibitory performance, based on gene set analysis, an approach to investigate multiple genetic variants simultaneously. Common variants within glutamatergic and GABAergic genes were investigated using the MAGMA software in an ADHD case-only sample (n=931), in which we assessed ASD symptoms and response inhibition on a Stop task. Gene set analysis for ADHD symptom severity, divided into inattention and hyperactivity/impulsivity symptoms, autism symptom severity and inhibition were performed using principal component regression analyses. Subsequently, gene-wide association analyses were performed. The glutamate gene set showed an association with severity of hyperactivity/impulsivity (P=0.009), which was robust to correcting for genome-wide association levels. The GABA gene set showed nominally significant association with inhibition (P=0.04), but this did not survive correction for multiple comparisons. None of single gene or single variant associations was significant on their own. By analyzing multiple genetic variants within candidate gene sets together, we were able to find genetic associations supporting the involvement of excitatory and inhibitory neurotransmitter systems in ADHD and ASD symptom severity in ADHD.

Is duration of illness really influencing outcome in major psychoses?

BACKGROUND

An increasing number of studies identifies the duration of illness (DI) as an important predictor of outcome in patients affected by major psychoses (MP). The aim of the present paper was to revise medical literature about DI and its effects on MP, focusing in particular on the relationship between DI and outcome with particular reference to treatment response, suicidal risk, cognitive impairment and social functioning.

METHODS

A search in the main database sources has been performed to obtain a comprehensive overview. Studies with different methodologies (open and double-blinded) have been included, while papers considering other variables such as duration of untreated episode/illness were excluded. MP included the diagnoses of schizophrenia, bipolar disorder and major depressive disorder.

RESULTS

Available data show that DI influences treatment response, suicidal risk and loss of social functioning in schizophrenic patients, while results are more controversial with regard to cognitive impairment. In bipolar disorder, a long DI has been associated with less treatment response, more suicidal risk and cognitive impairment, but more data are needed to draw definitive conclusions. Finally, studies, regarding DI of illness and its predictive value of outcome in major depressive disorder show contradictory results.

CONCLUSIONS

DI appears a negative outcome factor particularly for schizophrenia, while with regard to mood disorders, more data are needed to draw definitive sound conclusions.

Efficacy of drug treatment for acute mania differs across geographic regions: An individual patient data meta-analysis of placebo-controlled studies

Given globalization trends in the conduct of clinical trials, the external validity of trial results across geographic regions is questioned. The objective of this study was to examine the efficacy of treatment in acute mania in bipolar disorder across regions and to explain potential differences by differences in patient characteristics. We performed a meta-analysis of individual patient data from 12 registration studies for the indication acute manic episode of bipolar disorder. Patients (n = 3207) were classified into one of three geographic regions: Europe (n = 981), USA (n = 1270), and other regions (n = 956). Primary outcome measures were mean symptom change score on the Young Mania Rating Scale (YMRS) from baseline to endpoint and responder status (50% improvement form baseline). Effect sizes were significantly smaller in the USA (g = 0.203, 95% confidence interval (CI) 0.062-0.344; odds ratio (OR) 1.406, 95% CI 0.998-1.980) than in Europe (g = 0.476, 95% CI 0.200-0.672; OR 2.380, 95% CI 1.682-3.368) or other regions (g = 0.533, 95% CI 0.399-0.667; OR 2.300, 95% CI 1.800-2.941). Regional differences in age, gender, initial severity, body mass index, placebo response, discontinuation rate, and type of compound could not explain the geographic differences in effect. Less severe symptoms at baseline in the US patients did explain some of the difference in responder status between patients in Europe and the USA. These findings suggest that the results of studies involving patients with acute mania cannot be extrapolated across geographic regions. Similar findings have been identified in schizophrenia, contraceptive, and in cardiovascular trials. Therefore, this finding may indicate a more general problem regarding the generalizability of pharmacological trials over geographic regions.

Olanzapine-valproate combination versus olanzapine or valproate monotherapy in the treatment of bipolar I mania: a randomized controlled study in a Chinese population group

BACKGROUND

Bipolar disorder (BP) is a mental illness that has a high social burden estimated by disability-adjusted life years. In the present study, we investigated the efficacy of olanzapine-valproate combination therapy versus olanzapine or valproate monotherapy in the treatment of bipolar I mania in a Chinese population group.

SUBJECTS AND METHODS

Patients aged 19-58 years who had had an acute manic episode of BP were enrolled in the present study and randomly assigned to receive 600 mg sodium valproate daily (group A), 10 mg olanzapine daily (group B), or a combination of 600 mg olanzapine and 10 mg sodium valproate daily (group C) for 4 weeks. The primary outcome was reduction in Young Mania Rating Scale (YMRS) scores. The secondary outcome was assessed with the Clinical Global Impression - Bipolar (CGI-BP) scale. Adverse reactions, such as weight gain, sleepy, and dizziness were also evaluated. Statistical analysis was carried out on a per-protocol basis.

RESULTS

Patients in groups B and C showed significant improvement in YMRS scores compared with those in group A (P<0.01) during weeks 1-4 of treatment. Patients in group C showed significant improvement in YMRS scores compared with those in group B (P<0.01) only after 4 weeks of treatment. Furthermore, after 3-4 weeks of treatment, patients in groups B and C showed significantly greater improvement in CGI-BP scale scores compared with group A (P<0.05), while Group C demonstrated significantly greater improvement in CGI-BP scale scores than group B (P<0.01). No significant difference existed in extrapyramidal reactions among these groups. Adverse reactions, including weight gain, drowsiness, dizziness, and constipation, were stronger in groups B and C than in group A (P<0.05).

CONCLUSION

The combination therapy with olanzapine and sodium valproate had higher efficacy than monotherapy in patients with bipolar mania, which provides a crucial insight of the treatment regimen during clinical practice.

Alpha-2A adrenergic receptor gene variants are associated with increased intra-individual variability in response time

Intra-individual variability in response time has been proposed as an important endophenotype for attention deficit hyperactivity disorder (ADHD). Here we asked whether intra-individual variability is predicted by common variation in catecholamine genes and whether it mediates the relationship between these gene variants and self-reported ADHD symptoms. A total of 402 non-clinical Australian adults of European descent completed a battery of five cognitive tasks and the Conners' Adult ADHD Rating Scale. Exclusion criteria included the presence of major psychiatric or neurologic illnesses and substance dependency. A total of 21 subjects were excluded due to incomplete data or poor quality cognitive or genotyping data. The final sample comprised 381 subjects (201 males; mean age=21.2 years, s.d.=5.1 years). Principal components analysis on variability measures yielded two factors (response selection variability vs selective attention variability). Association of these factors with catecholamine gene variants was tested using single-step linear regressions, with multiple comparisons controlled using permutation analysis. The response selection variability factor was associated with two ADRA2A single-nucleotide polymorphisms (SNPs) (rs1800544, rs602618), p corrected=0.004, 0.012, respectively, whereas the selective attention variability factor was associated with a TH SNP (rs3842727), p corrected=0.024. A bootstrapping analysis indicated that the response selection variability factor mediated the relationship between the ADRA2A SNP rs1800544 and self-reported ADHD symptoms. Thus this study finds evidence that DNA variation in the ADRA2A gene may be causally related to ADHD-like behaviors, in part through its influence on intra-individual variability. Evidence was also found for a novel association between a TH gene variant and intra-individual variability.

Parent-of-origin effects in ADHD: distinct influences of paternal and maternal ADHD on neuropsychological functioning in offspring

OBJECTIVE

The authors examined parent-of-origin effects in transmission of ADHD and neuropsychological functioning. Proof of these effects can identify more etiologically homogeneous ADHD subgroups and facilitate genetic studies.

METHOD

The authors included 238 ADHD and 147 control families. ADHD in children was assessed using parent and teacher ratings, while parents completed self-reports. Children were assessed with neuropsychological paradigms measuring IQ, motor, timing, and executive functions.

RESULTS

Paternal and maternal ADHD were equally positively related to ADHD in offspring. Paternal ADHD was related to poorer time reproduction in offspring and to lower verbal and total IQ in daughters. Maternal ADHD was related to poorer inhibition and motor control in offspring. No mediating effects of neuropsychological functions were found between parent and offspring ADHD symptoms.

CONCLUSION

Neuropsychological functions may be more sensitive to parent-of-origin effects than ADHD symptoms and possibly useful in detecting the transmission of different gene-brain network pathways depending on parental sex.

Clinical predictors of ketamine response in treatment-resistant major depression

OBJECTIVE

The N-methyl-D-aspartate receptor antagonist ketamine has rapid antidepressant effects in treatment-resistant major depressive disorder (MDD) and bipolar depression. Clinical predictors may identify those more likely to benefit from ketamine within clinically heterogeneous populations.

METHOD

Data were analyzed from 4 studies of treatment-resistant inpatients with DSM-IV-TR-diagnosed MDD or bipolar I or II depression. Patients who were currently experiencing a moderate-to-severe major depressive episode were enrolled between November 2004 and March 2013. All subjects received a single subanesthetic (0.5 mg/kg) ketamine infusion over 40 minutes. Patients were analyzed at the 230-minute postinfusion time point (n = 108), at day 1 (n = 82), and at day 7 (n = 71). Univariate Pearson correlations were performed for each variable with percent change from baseline in the 17-item Hamilton Depression Rating Scale (HDRS). Multivariate linear regression was then conducted for statistically significant predictors (P ≤ .05, 2-tailed).

RESULTS

Higher body mass index correlated with greater HDRS improvement at 230 minutes (standardized β = -0.30, P = .004) and at day 1 (standardized β = -0.37, P = .001), but not at day 7 (standardized β = -0.18, P = .10). Family history of an alcohol use disorder in a first-degree relative was associated with greater HDRS improvement at day 1 (standardized β = -0.27, P = .014) and day 7 (standardized β = -0.41, P < .001). No prior history of suicide attempt(s) was associated with greater improvement only at day 7 (standardized β = 0.28, P = .01). The overall statistical model explained 13%, 23%, and 36% of HDRS percent change variance at 230 minutes, day 1, and day 7, respectively.

CONCLUSIONS

Despite its post hoc nature, this study identified several clinical correlates of ketamine's rapid and durable antidepressant effects. Further investigation of these relationships is critical for individualized treatment of depression.

Comparative effectiveness of monotherapy with mood stabilizers versus second generation (atypical) antipsychotics for the treatment of bipolar disorder in children and adolescents

OBJECTIVE

This study compared the effectiveness and safety of second generation (atypical) antipsychotic (SGA) versus traditional mood stabilizers (MS) in children and adolescents with bipolar disorder.

METHODS

The study was a retrospective cohort study on 5 years (2003-2007) of Medicaid claims data from four geographically diversified states. Children and adolescents aged 6-18 years who initiated a new treatment episode for bipolar disorder on either an SGA or an MS were followed for 12 months to compare the effectiveness and safety between the two therapeutic categories for pediatric bipolar disorder (PBD). The outcome measures were psychiatric hospital admission, all cause medication discontinuation and treatment augmentation. Potential selection bias caused by unobserved confounding was addressed with instrumental variable methods, using physician prescribing preference and year of cohort entry as the instruments. Sensitivity analysis was conducted to test the robustness of findings against the uncertainties on PBD diagnosis.

RESULTS

Of the 7423 bipolar children and adolescents identified, 66.60% started treatment on SGA, whereas 33.40% initiated on MS. Patients who initiated on MS and SGA had comparable risk of psychiatric hospital admission (HR=1.172, 95%CI: 0.827-1.660). However, as compared with those who initiated on MS, patients who initiated on SGA were less likely to discontinue the treatment (HR=0.634, 95%CI: 0.419-0.961) and less likely to receive treatment augmentation (HR=0.223, 95%CI: 0.103-0.484).

CONCLUSION

As compared with MS monotherapy, SGA monotherapy could be a more effective and safer treatment option for PBD.

Response inhibition and ADHD traits: correlates and heritability in a community sample

Endophenotypes or intermediate phenotypes are of great interest in neuropsychiatric genetics because of their potential for facilitating gene discovery. We evaluated response inhibition, latency and variability measures derived from the stop task as endophenotypes of ADHD by testing whether they were related to ADHD traits in the general population, heritable and shared genetic risk with ADHD traits. Participants were 16,099 children and adolescents, ages 6 to 18 years who visited a local science center. We measured ADHD traits using the Strengths and Weaknesses of ADHD-symptoms and Normal-Behavior (SWAN) rating scale and performance on the stop signal task (SST)-response inhibition (SSRT), response latency (GoRT), and response variability (GoRTSD). Regression analysis was used to assess the relationship of cognitive measures and ADHD traits while controlling for family, age, sex, ethnicity, socioeconomic status and treatment status. Heritability of ADHD and cognitive traits was estimated using SOLAR in 7,483 siblings from 3,507 families that included multiple siblings. Bivariate relationships between pairs of variables were examined. Individuals with greater ADHD trait scores had worse response inhibition, slower response latency, and greater variability. Younger participants and girls had inferior performance although the gender effects were minimal and evident in youngest participants. Inhibition, latency, variability, total ADHD traits, inattention and hyperactivity-impulsivity scores were significantly heritable. ADHD traits and inhibition, but not latency or variability were coheritable. In the largest study in the general population, we found support for the validity of response inhibition as an endophenotype of ADHD.

The utilization of psychopharmacological treatment and medication adherence among Medicaid enrolled children and adolescents with bipolar depression

BACKGROUND

To examine the psychotropic medication utilization and compare adherence to treatment regimens in pediatric bipolar depression patients.

METHODS

2003-2007 MAX data from four geographically diverse states were used. According to the regimen received by the patients (6-18 years) in the first month after the index bipolar depression diagnosis, patients were categorized into six mutually exclusive groups. The month to month change of treatment regimen in each group was then assessed during the 6 month post-index bipolar depression diagnosis. Adherence to each regimen was measured as continuation of the initial regimen, switch to a new regimen, augmentation with medication from a different therapeutic category, and discontinuation of all pharmacotherapies. Repeated measure analysis was conducted to compare the trend of each adherence measure across the study groups.

RESULTS

Of the 5,460 subjects identified, 15.39% received antipsychotic monotherapy, 9.43% received mood stabilizer monotherapy, 5.77% received antidepressant monotherapy, 26.48% received mood stabilizer-antipsychotic polytherapy, 22.51% received antidepressant polytherapy, and 19.89% received antipsychotic-mood stabilizer-antidepressant polytherapy. At the end of the follow-up period, over 50% of the 1st month polytherapy users and less than 50% of the monotherapy users were continuing their initial regimen. Repeated measure analysis using antipsychotic monotherapy as the reference group suggested differences in trend slopes (p<0.05).

LIMITATIONS

In absence of structured clinical evaluation, bipolar disorder diagnoses cannot be ascertained in this study.

CONCLUSIONS

Bipolar depression patients were predominantly treated with combinations of psychotropic drugs. Potentially questionable practice, such as antidepressant monotherapy was used only in a small fraction of patients. Combination regimens had better adherence as compared to monotherapies.

Biochemical correlates of neuropsychiatric illness in maple syrup urine disease

Maple syrup urine disease (MSUD) is an inherited disorder of branched chain amino acid metabolism presenting with neonatal encephalopathy, episodic metabolic decompensation, and chronic amino acid imbalances. Dietary management enables survival and reduces risk of acute crises. Liver transplantation has emerged as an effective way to eliminate acute decompensation risk. Psychiatric illness is a reported MSUD complication, but has not been well characterized and remains poorly understood. We report the prevalence and characteristics of neuropsychiatric problems among 37 classical MSUD patients (ages 5-35 years, 26 on dietary therapy, 11 after liver transplantation) and explore their underlying mechanisms. Compared with 26 age-matched controls, MSUD patients were at higher risk for disorders of cognition, attention, and mood. Using quantitative proton magnetic resonance spectroscopy, we found lower brain glutamate, N-acetylaspartate (NAA), and creatine concentrations in MSUD patients, which correlated with specific neuropsychiatric outcomes. Asymptomatic neonatal course and stringent longitudinal biochemical control proved fundamental to optimizing long-term mental health. Neuropsychiatric morbidity and neurochemistry were similar among transplanted and nontransplanted MSUD patients. In conclusion, amino acid dysregulation results in aberrant neural networks with neurochemical deficiencies that persist after transplant and correlate with neuropsychiatric morbidities. These findings may provide insight into general mechanisms of psychiatric illness.

Two-year follow-up status of emergency department patients with chest pain: Was it panic disorder?

OBJECTIVES

We previously reported that 25% (108/441) of consecutive patients presenting to the emergency department (ED) of the Montreal Heart Institute with a chief complaint of chest pain suffered from panic disorder (PD). The purpose of the present study was to re-examine these patients (with and without PD) 2 years after their initial ED visit to determine their psychiatric and psychosocial status.

METHODS

An interviewer, who was kept blind to patients' initial medical and psychiatric diagnoses, attempted to contact all patients who participated in the initial study by phone. Patients who completed the phone interview were sent a battery of psychological questionnaires by mail.

RESULTS

A total of 301 (70%) patients completed the phone interview, and 228 (52%) patients completed the self-report questionnaires. Participants and non-participants did not differ with respect to age, gender, initial self-report scores, or initial cardiac or psychiatric diagnoses. At follow-up, significantly (p < 0.05) more PD+ than non-PD (PD-) patients reported: 1) chest pains in the last month (57% vs. 31%); 2) one or more ED consultations in the past year for chest pain (40% vs. 14%); 3) one or more hospitalizations in the past year (31% vs. 11%); and 4) perceiving their general health as "poor" (22% vs. 9%). PD+ patients displayed a significant (p < 0.05) worsening of their panic symptoms, agoraphobic avoidance, depression, and trait anxiety, and reported significantly (p < 0.05) greater suicidal ideation compared to PD- patients (32% vs. 9%). Of all PD+ patients, only 22% (18/82) reported receiving some form of mental health treatment for their symptoms.

CONCLUSIONS

Unrecognized and untreated PD has a chronic and disabling course. Greater efforts should be made to screen for PD in patients complaining of chest pain in EDs.

Examining autistic traits in children with ADHD: does the autism spectrum extend to ADHD?

We examined to what extent increased parent reports of autistic traits in some children with Attention Deficit Hyperactivity Disorder (ADHD) are the result of ADHD-related symptoms or qualitatively similar to the core characteristics of autism spectrum disorders (ASD). Results confirm the presence of a subgroup of children with ADHD and elevated ratings of core ASD traits (ADHD(+)) not accounted for by ADHD or behavioral symptoms. Further, analyses revealed greater oppositional behaviors, but not greater ADHD severity or anxiety, in the ADHD(+) subgroup compared to those with ADHD only. These results highlight the importance of specifically examining autistic traits in children with ADHD for better characterization in studies of the underlying physiopathology and treatment.

An asymmetric stroop/reverse-stroop interference phenomenon in ADHD

OBJECTIVE

To examine whether participants with ADHD showed a deficit in Stroop/reverse-Stroop interference by comparing them to non-ADHD participants.

METHOD

A group with ADHD, primarily inattentive type (n = 15), and a paired non-ADHD group (n = 15) completed the group version of the Stroop/reverse-Stroop test.

RESULTS

Asymmetric interference was observed between the Stroop test and the reverse-Stroop test in ADHD participants, presenting evidence contrary to Barkley's behavioral inhibition model of ADHD in which response inhibition deficits pertained only to the ADHD-C subtype.

CONCLUSION

Participants with ADHD showed a control deficit in reverse-Stroop interference but not in Stroop interference.

Treatment of schizoaffective disorder - a challenge for evidence-based psychiatry

OBJECTIVE

Schizoaffective disorder is a common diagnosis in mental health services. The aim of the present article was to review treatment studies for schizoaffective disorder and draw conclusions for clinical decision making.

METHOD

We searched MEDLINE and Cochrane Library for relevant clinical trials and review articles up to the year 2008.

RESULTS

Thirty-three studies using standardized diagnostic criteria, 14 of which were randomized controlled trials, could be identified. The comparability of studies is limited by the use of different diagnostic criteria. The studies reviewed do not permit consistent recommendations as to whether schizoaffective disorder should be treated primarily with antipsychotics, mood stabilizers or combinations of these drugs. The relevance of diverse subtypes of schizoaffective disorder for treatment recommendations is unclear.

CONCLUSION

The pertinent empirical database is small and heterogeneous. The lack of conclusive recommendations is related to issues of nosological status, plurality of diagnostic criteria and validity of the concept of schizoaffective disorder.

The cost of relapse for patients with a manic/mixed episode of bipolar disorder in the EMBLEM study

BACKGROUND

Bipolar disorder (BD) is characterized by episodes of mania and depression. The debilitating symptoms during an acute episode require intensive treatment, frequently leading to inpatient psychiatric care, which places significant demands on health and social care systems and incurs substantial costs. However, no study to date has estimated the economic impact of relapse.

OBJECTIVES

To estimate the direct costs associated with relapse in the treatment of BD following an acute manic or mixed episode over a 21-month follow-up period in routine clinical practice in Europe, using data from a large, prospective, observational study.

METHODS

EMBLEM was a prospective, observational study on the outcomes of patients with a manic/mixed episode of BD conducted in 14 European countries. Patients eligible for analysis were those enrolled in the 21-month maintenance phase of the study, following the 3-month acute phase. Relapse was defined as achieving any one of the following criteria: (i) at least a one-point increase in Clinical Global Impression - Bipolar Disorder (CGI-BP) overall score from the previous visit, with a final rating of > or =4; (ii) inpatient admission for an acute episode of BD; or (iii) psychiatrists' confirmation of relapse. Data on healthcare resource use were recorded retrospectively for the four respective periods (3-6, 6-12, 12-18 and 18-24 month visits). Multivariate analyses were performed to compare the cost of resource use (inpatient stay, day care, psychiatrist visits and medication) for those who relapsed during the 21-month maintenance phase and those who never relapsed. A sensitivity analysis was also conducted to examine the 6-month costs during relapse. The analyses were adjusted for patient characteristics and took account of non-Normality of the cost data by using a log link function. UK unit costs were applied to resource use. The analysis was repeated after multiple imputation for missing data. All costs were presented as year 2007/08 values.

RESULTS

A total of 1379 patients completed all visits during the maintenance phase and were eligible for inclusion in the present analysis. Of these, over half (54.3%) experienced relapse during this period. A total of 792 patients without any missing data were eventually included in the final cost model. Costs incurred by patients who relapsed during the 21-month maintenance phase were approximately double those incurred by patients who never relapsed (pounds sterling 9140 vs pounds sterling 4457; p < 0.05). Of the cost difference, 80.3% was accounted for by inpatient stay. Estimates on the economic impact were higher (pounds sterling 11,781 vs pounds sterling 4789; p < 0.05) in the additional analysis with imputed missing data. The impact of relapse was even greater in the 6-month cost comparison. The average 6-month costs for patients who relapsed were found to be about three times higher than for those who did not relapse (pounds sterling 4083 vs pounds sterling 1298; p < 0.05).

CONCLUSIONS

Our findings confirm the significant economic impact of relapse in BD patients after an acute manic or mixed episode, even when considering direct costs only. Such costs were dominated by inpatient stay. Nevertheless, the use of UK unit costs requires caution when interpreting this costing in the context of a specific country, as resource use and the associated costs will differ by country.

Preliminary study of the prevalence of restless legs syndrome in adults with attention deficit hyperactivity disorder

Several previous studies have shown that Attention Deficit Hyperactivity Disorder (ADHD) is common in children with Restless Legs Syndrome and ADHD is more common in adults with this syndrome. This pilot study examined the prevalence of Restless Legs Syndrome in adults with ADHD, showing six of 30 adult ADHD participants (20%) had Restless Legs Syndrome. This estimate exceeds the prevalence (7.2%) for a previously published control group. These six adults had more severe ADHD symptomatology than those without Restless Legs Syndrome based on the overall Conners' Adult ADHD Rating Scale. Such results suggest that symptoms of Restless Legs Syndrome may occur often in adults with ADHD and might worsen the symptoms of ADHD. Replication with a larger sample size is in order.

Pharmacotherapy of adult attention deficit hyperactivity disorder (ADHD): a meta-analysis

Our objective was to conduct a meta-analysis of therapeutic efficacy of pharmacological treatment of adult ADHD based on data from controlled clinical trials. We used the search engines PubMed and Medline to identify relevant clinical trials. Short-term studies with double-blind parallel-group design were selected for the analysis. Altogether, we identified 11 trials that met the criteria, and investigated a total of 1991 subjects, 694 and 1297 of whom were treated with placebo or active medication, respectively. In order to pool efficacy data from studies with different characteristics, including different number of participants, different trial duration and measures of efficacy, the statistical effect sizes for each study had to be calculated. Our findings showed that the pooled effect size across all treatments was in the medium-to-high range (Cohen's d=0.65, p<0.0001 vs. placebo), and the effect size for stimulants (Cohen's d=0.67, p<0.0001 vs. placebo) was somewhat higher than for non-stimulant medications (Cohen's d=0.59, p<0.0001 vs. placebo). The current database of controlled trials for adult ADHD is relatively small, and does not include data for many of the potentially important agents. In addition, effect-size estimates for different classes of medications (i.e. stimulant and non-stimulant medications) were based on separate studies; head-to-head comparisons of various agents are severely lacking. Nonetheless, results of this meta-analysis across all ADHD medications in adult subjects demonstrated statistically significant and clinically robust improvement in symptom severity compared to placebo treatment.

Current considerations in the treatment of generalized anxiety disorder

Generalized anxiety disorder (GAD) is a chronic disorder that frequently co-occurs with a variety of co-morbidities in patients with somatic conditions and other mental disorders. GAD is highly prevalent and is one of the most common anxiety disorders seen by primary care physicians. The individual and societal cost associated with GAD is high and the marked level of impairment experienced by patients with this disorder is equivalent in magnitude to that reported in patients with major depressive disorder. Furthermore, patients with GAD are at risk of suicide or suicide attempts, and are frequent users of healthcare services. Thus, GAD is a serious and chronic condition that requires appropriate long-term treatment. The focus of acute treatment for patients with GAD is the improvement of symptoms, while the primary goal of long-term clinical management is remission, i.e. the complete resolution of both symptoms and functional impairment. The consensus across current treatment guidelines is that first-line treatment for patients with GAD should consist of an antidepressant, either a selective serotonin reuptake inhibitor (SSRI) such as sertraline, paroxetine or escitalopram, or a selective serotonin noradrenaline (norepinephrine) reuptake inhibitor (SNRI) such as venlafaxine or duloxetine. However, the SSRIs and SNRIs have efficacy limitations, such as lack of response in many patients, a 2- to 4-week delay before the onset of symptom relief, lack of full remission, and risk of relapse. In addition, there are troublesome adverse effects associated with both the SSRIs and SNRIs. Evidence from early clinical studies of the atypical antipsychotics in the treatment of anxiety and GAD indicate that they may have a potential role in the treatment of GAD, either as monotherapy or as augmentation to standard treatment.

Tryptophan research in panic disorder

A considerable body of evidence suggests the involvement of serotonin neurotransmission in the pathogenesis of panic disorder. Research on pathways and functions of tryptophan, an essential amino acid converted into serotonin, may advance our understanding of serotonergic actions in panic disorder and related phenomena. The investigative approaches in this field include manipulations of tryptophan availability as well as genetic association and functional brain imaging studies. In this review we examine the principle findings of these studies and propose further research directions.

Characteristics of adults with attention-deficit/hyperactivity disorder and past conduct disorder

OBJECTIVE

DSM-IV Attention-deficit/hyperactivity disorder (ADHD) comorbid with DSM-IV conduct disorder (CD) in childhood/adolescence has been proposed as a 'distinct subtype'. The present study investigated subsequent psychopathological characteristics of this proposed subtype in adults.

METHOD

Questionnaires were completed by 71 adults (mean age 29.6 years) with ADHD and their informants.

RESULTS

The 39 subjects with a history of past CD, when compared with the remaining subjects, were associated with significantly increased ratings of aspects of ADHD-related impulsivity, with features of all three DSM-IV 'Clusters' of personality disorders (PDs) (in particular of 'Cluster B' PDs) and with other psychopathology. Also, there were significant correlations between the number of endorsed past CD criteria and various self-ratings of psychopathology.

CONCLUSION

The results indicate the psychopathological characteristics of adults with a history of the proposed 'ADHD with CD' subtype. The findings are relevant to future studies of ADHD subtypes in adults.

A comprehensive approach to treating autism and attention-deficit hyperactivity disorder: a prepilot study

OBJECTIVES

The purpose of this study was to observe the effects of a multi dimensional treatment plan involving nutrition, environmental control, chelation, and behavioral/educational/physical/speech therapy to treat children with autistic spectrum disorder and attention-deficit hyperactivity (ADHD) disorder. This study is only a preliminary study, and its small size (10 patients) precludes statistical analysis of simultaneous multiple modal treatment regimes.

DESIGN

This was an open-label observational study. SETTINGS/LOCATION/SUBJECTS: This study examined 10 children aged 4-10 years old who had been diagnosed with both autistic spectrum disorder and ADHD by outside physicians or psychologists. These 10 children presented consecutively in an environmental medicine clinic in Buffalo, New York. The children were given comprehensive nutritional/environmental/chelation treatment for 3 to 6 months in addition to their usual behavioral, educational, speech, and physical therapies.

OUTCOME MEASURES

Study outcomes were measured by objective/subjective improvement as judged by physicians/parents/teachers. Outcomes were also measured by changes in urinary heavy metal burdens over time.

RESULTS

All 10 children showed significant improvement in many areas of social interaction, concentration, writing, language, and behavior. Urinary lead burden dropped significantly in all 10 children.

CONCLUSIONS

Autistic spectrum disorders and ADHD are complicated conditions that probably require multidimensional treatment strategies. Larger studies are needed to determine optimum treatment plans involving nutrition, environmental control, medication, and behavioral/education/speech/physical therapies.

Olanzapine in the treatment of depression with psychotic features: A prospective open-label study

Objective. Depression with psychotic features is a severe subtype of major depression associated with the presence of delusions, hallucinations and specific neurobiological features. Despite clinical consensus and guideline recommendations, data comparing the efficacy of combining antipsychotics with antidepressants compared to antidepressants alone remain inconclusive. The aim of the study was to investigate effectiveness and tolerability of the atypical antipsychotic olanzapine in acute depression with psychotic features. Methods. Seventeen inpatients with major depressive disorder with psychosis (MDDp) were treated with a combination of an antidepressant and olanzapine for 6 weeks in a prospective open-label study. Depressive and psychotic symptoms, extrapyramidal and general side effects were assessed every 2 weeks. Sixteen patients were eligible for final analysis. Results. The Brief Psychiatric Rating Scale (BPRS) showed a 30% symptom reduction after week 2, a 45% symptom reduction after week 4 and no considerable improvement thereafter. Depressive symptoms (Bech-Rafaelsen Melancholia Scale, BRMS) receded by 37% after week 2 and 50% after week 4. No extrapyramidal side effects occurred. Conclusion. Olanzapine is effective and tolerable in combination with an antidepressant in an MDDp inpatient sample. The results concur with data supporting good efficacy in negative and depressive symptoms of patients with schizophrenic and schizoaffective diseases.

The social, psychopathological and consumer context of rate of symptom improvement in acute mania

BACKGROUND

Knowledge of moderators of symptom improvement over time in acute mania improves predictability of individual patient outcomes. This study attempted to identify such moderators of the rate of symptom improvement.

METHODS

In 3459 patients with high levels of mania in whom a change in psychotropic treatment was initiated and who were assessed six times over three months, clinical and social moderators of the rate of response were examined. Additionally, moderators of symptom improvement in individuals with high baseline levels of comorbid depression (n = 815) and psychosis (n = 1849) were identified.

RESULTS

Within three months, mania symptoms were reduced by 52%, psychotic symptoms by 56% and depressive symptoms by 36%. High levels of baseline depression, greater illness severity in the past year, lower age of onset and rapid cycling reduced the rate of mania symptom improvement by 5-15%. Social variables indicating disadvantage similarly had negative contributions (5%-14%). Several reasons for change of medication involving patient choice, patient compliance, side effects and lack of effectiveness impacted negatively (reductions of 10%, 6%, 14% and 9% respectively). For the psychosis dimension, both low mania scores (22% reduction) and high depression scores (14% reduction) at baseline impacted negatively, whereas rate of reduction in depression was not conditional on baseline psychopathology.

CONCLUSIONS

The rate of symptom improvement in acute mania is to a large extent conditional on the context as provided by the social, psychopathological and consumer environment. Understanding the context of treatment response offers valuable insights into treatment approaches aimed at moderation of traditional pharmacological interventions.

Dopaminergic genotype biases spatial attention in healthy children

In everyday life, our sensory system is bombarded with visual input and we rely upon attention to select only those inputs that are relevant to behavioural goals. Typically, humans can shift their attention from one visual field to the other with little cost to perception. In cases of 'unilateral neglect', however, there is a persistent bias of spatial attention towards the same side as the damaged cerebral hemisphere. We used a visual orienting task to examine the influence of functional polymorphisms of the dopamine transporter gene (DAT1) on individual differences in spatial attention in normally developing children. DAT1 genotype significantly influenced spatial bias. Healthy children who were homozygous for alleles that influence the expression of dopamine transporters in the brain displayed inattention for left-sided stimuli, whereas heterozygotes did not. Our data provide the first evidence in healthy individuals of a genetically mediated bias in spatial attention that is related to dopamine signalling.

An investigation of the neurotrophic factor genes GDNF, NGF, and NT3 in susceptibility to ADHD

Attention deficit hyperactivity disorder (ADHD) is a common, highly heritable, neurodevelopmental disorder with onset in early childhood. Genes involved in neuronal development and growth are, thus, important etiological candidates and neurotrophic factors have been hypothesized to play a role in the pathogenesis of ADHD. Glial derived neurotrophic factor (GDNF), nerve growth factor (NGF (beta subunit)), and neurotrophic factor 3 (NT3) are members of the neurotrophin family and are involved in the survival, differentiation, and maintenance of neuronal cells. We have examined 10 coding and intronic single nucleotide polymorphisms (SNPs) across GDNF, NGF, and NT3 in a family-based association sample of 120 DSM-IV ADHD probands and their biological parents, as well as a case-control analysis with 120 sex-matched controls. Borderline significant overtransmission of the C allele of a non-synonymous C/T SNP (rs6330) in NGF which codes an alanine/valine change was found in the family-based sample (Chi-square = 3.69, odds ratio (OR) = 1.65, P = 0.05). Although this SNP is located in the 5' pro-NGF sequence and not the mature NGF protein, it may affect intracellular processing and secretion of NGF.

Cognitive remediation in ADHD: effects of periodic non-contingent alerts on sustained attention to response

Few studies have attempted direct cognitive remediation of attention deficits in attention-deficit hyperactivity disorder (ADHD). The present study investigated the efficacy of periodic non-informative alerting cues for improving sustaining attention in ADHD. This technique is known to improve sustained attention in right frontal injury patients and may be effective in ADHD, given that this disorder has also been linked with right frontal dysfunction. Fifteen children with ADHD and 15 matched controls completed four blocks of a modified version of the Sustained Attention to Response Task (SART). Eight random non-contingent alerts were introduced on two of these blocks as a cue for participants to adopt a more supervisory stance to their performance. While the alerting cues did not alter the total number of commission errors committed by ADHD children over a task block, they did produce a significant short-term reduction in commission errors in the period immediately following an alerting cue. Our data demonstrate that sustained attention performance can be enhanced in children with ADHD using a simple cognitive training strategy. Methods from the field of cognitive rehabilitation may be viably applied to the remediation of attention deficits in ADHD.

Striatal D(2) receptor occupancy in bipolar patients treated with olanzapine

We explored the relationship between striatal dopamine-2 (D(2)) receptor occupancy and extra-pyramidal symptoms (EPS) in bipolar patients receiving olanzapine. Seventeen patients with a DSM-IV diagnosis of bipolar disorder were treated with 5-45 mg/day olanzapine for at least 14 days. After that period, D(2) receptor occupancy was determined using Iodobenzamide (IBZM) and SPECT. EPS were assessed by the Simpson-Angus Scale (SAS) and Barnes-Akathisia Scale (BAS). We found a dose-dependent increase in occupancy: 5 mg led to 28-50%, 10 mg to 40-68%, 15 mg to 69%, 20 mg to 57-66%, 30 mg to 66% and 45 mg to 80% D(2) receptor occupancy; and a significant correlation between plasma levels and occupancy (R(2)=.55, P=.001). Similar to schizophrenic patients, bipolar patients did not exhibit EPS at D(2) occupancy levels of 28 to 80%. Although we did not find an increased vulnerability for acute EPS in bipolar patients receiving olanzapine at clinical relevant doses, this needs to be replicated with larger sample sizes.

A family-based study of Indian subjects from Kolkata reveals allelic association of the serotonin transporter intron-2 (STin2) polymorphism and attention-deficit-hyperactivity disorder (ADHD)

Serotonin transporter (SLC6A4) polymorphisms are variously implicated in mediating susceptibility to attention-deficit-hyperactivity disorder (ADHD), a highly heritable and heterogeneous disorder with onset in childhood. Since there has been no survey in this regard from India, a sample of 56 ADHD cases and 174 healthy individuals from Kolkata were genotyped for the SLC6A4 promoter (5-HTTLPR) and intron-2 (STin2) polymorphisms. We report that the observed distribution of allele frequencies is consonant with that expected as per Hardy-Weinberg equilibrium proportions. Pair-wise combination of alleles comprising the 5-HTTLPR and STin2 polymorphic systems exhibit significant (chi(2) = 14.74, df = 1; P = 0.0001) linkage disequilibrium of low magnitude (D' = 0.269). The estimates of haplotype-based haplotype relative risk (HHRR) (chi(2) = 4.92, P = 0.027; RR = 1.47; 95% CI = 1.01-2.13) and transmission disequilibrium test (TDT) statistics (chi(2) = 7.00, P = 0.008; OR = 3.00; 95% CI = 1.53-5.90) using a family-based study design, indicate significant preferential transmission of the STin2.12 (A12) allele to ADHD cases. Maternal inheritance of the A12 allele is significant in terms of the HHRR (chi(2) = 6.53, P = 0.011; RR = 2.00; 95% CI = 1.08-3.72) and TDT (chi(2) = 8.07, P = 0.005; OR = 6.50; 95% CI = 1.76-23.98) suggesting a novel role for epigenetic mechanisms in the etiology of ADHD. Similar analyses yielded no evidence of association between the 5-HTTLPR polymorphism and ADHD. Studies including additional polymorphic markers, ADHD subjects and other ethnic groups are warranted to further substantiate the present findings.

Clinical assessment and treatment of attention deficit hyperactivity disorder in adults

Attention deficit hyperactivity disorder (ADHD) is a common childhood disorder that frequently persists into adulthood, with significant levels of inattentive, hyperactive and impulsive behavior. Impairments associated with adult ADHD include distress from the symptoms, impaired ability to function in work and academic settings, and problems sustaining stable relationships. The disorder is commonly associated with volatile moods, antisocial behavior, and drug and alcohol misuse. There is an increased risk of developing comorbid anxiety, depression, personality disorders, and drug and alcohol dependence. Despite the proven effectiveness of drugs such as methylphenidate, dexamphetamine and atomoxetine, few cases of ADHD are recognized and treated in the UK. The reasons for this are unclear, since most psychiatrists working with children and adolescents are aware that ADHD commonly persists into adult life and they also see the disorder affecting parents of children with ADHD. Issues of transition from the care of child to adult psychiatry and the need to refer adult relatives of children with ADHD to suitable psychiatric services are a major concern. Furthermore, many cases of adult ADHD go unrecognized or are seen by mental health teams that are not familiar with the subtleties of the adult presentation. As a result, misdiagnosis and treatment for conditions such as atypical depression, mixed affective disorder, cyclothymia, and borderline and unstable emotional personality disorders is not uncommon. There is therefore a requirement for further training in this area. This review will describe the common clinical presentation and provide guidelines for the diagnosis and treatment of ADHD in adults. Any psychiatrically trained physician using standard psychiatric assessment procedures can perform clinical evaluations for adult ADHD. As with other psychiatric disorders in adulthood, ADHD has its own characteristic onset, course and psychopathology. Symptoms of ADHD are trait-like, being stable characteristics from early childhood, and commonly co-occur with affective instability. Stimulants are the mainstay of treatment and are effective in around 70% of cases. Psychotherapeutic interventions also have an important role. These guidelines will assist psychiatrists and other adult mental health workers in identifying and treating individuals with adult ADHD.

The role of quetiapine in the treatment of bipolar disorder

Through a review of randomised, controlled trials, this article evaluates the efficacy and tolerability of quetiapine in the acute and maintenance phases of bipolar disorder. In trials involving mania patients, quetiapine was found to be effective as adjunctive therapy in combination with lithium or valproate, significantly superior to placebo, and equal to lithium or haloperidol as monotherapy. With regard to the prevention of relapses in bipolar disorder, quetiapine seems to differ from other atypical antipsychotics in its characteristics as a mood stabiliser, which are associated with a promising efficacy in the treatment of bipolar depressive episodes. However, further larger controlled long-term prospective studies are needed to confirm the efficacy of quetiapine for the prevention of relapses in bipolar disorder. Quetiapine seems to have a satisfactory safety and tolerability profile, with a low prevalence of extrapyramidal symptom-related adverse events, treatment-emergent depression and weight gain. Sedation is the main side effect of treatment with quetiapine.

Serotonin function in panic disorder: important, but why?

The essential role of serotonin (5-hydroxytryptamine (5-HT)) system in the neurobiology and pharmacotherapy of panic disorder (PD) continues to be a topic of intensive interdisciplinary research. Interest in the involvement of 5-HT in PD has been fuelled by clinical studies demonstrating that medications increasing the synaptic availability of 5-HT, such as selective 5-HT re-uptake inhibitors, are effective in the treatment of PD. Rival theories of 5-HT deficiency vs excess have attempted to explain the impact of 5-HT function in PD. In the past decade, knowledge of the role of 5-HT in the neurobiology of PD has expanded dramatically due to much new research including experimental, treatment, brain-imaging, and genetic studies. The current review attempts to summarize the new data and their implications. The challenge and treatment studies generally confirm the specific inhibitory influence of 5-HT on panicogenesis. The brain-imaging studies in PD patients demonstrate functional and clinically relevant alterations in various elements of 5-HT system affecting the neurocircuitry of panic. The findings of genetic association studies suggest that certain 5-HT-related genes may contribute to the susceptibility to PD; however, these data are rather limited and inconsistent. It appears that, even if not the primary etiological factor in PD, the 5-HT function conveys important vulnerability, as well as adaptive factors. A better understanding of these processes may be critical in achieving progress in the treatment of patients suffering from PD.

Association between dopamine transporter (DAT1) genotype, left-sided inattention, and an enhanced response to methylphenidate in attention-deficit hyperactivity disorder

A polymorphism of the dopamine transporter gene (DAT1, 10-repeat) is associated with attention-deficit hyperactivity disorder (ADHD) and has been linked to an enhanced response to methylphenidate (MPH). One aspect of the attention deficit in ADHD includes a subtle inattention to left space, resembling that seen after right cerebral hemisphere damage. Since left-sided inattention in ADHD may resolve when treated with MPH, we asked whether left-sided inattention in ADHD was related to DAT1 genotype and the therapeutic efficacy of MPH. A total of 43 ADHD children and their parents were genotyped for the DAT1 3' variable number of tandem repeats polymorphism. The children performed the Landmark Test, a well-validated measure yielding a spatial attentional asymmetry index (leftward to rightward attentional bias). Parents rated their child's response to MPH retrospectively using a three-point scale (no, mediocre or very good response). Additionally, parents used a symptom checklist to rate behavior while on and off medication. A within-family control design determined whether asymmetry indices predicted biased transmission of 10-repeat parental DAT1 alleles and/or response to MPH. It was found that left-sided inattention predicted transmission of the 10-repeat allele from parents to probands and was associated with the severity of ADHD symptomatology. Children rated as achieving a very good response to MPH displayed left-sided inattention, while those rated as achieving a poorer response did not. Our results suggest a subgroup of children with ADHD for whom the 10-repeat DAT1 allele is associated with left-sided inattention. MPH may be most efficacious in this group because it ameliorates a DAT1-mediated hypodopaminergic state.

Insights into the control of attentional set in ADHD using the attentional blink paradigm

BACKGROUND

Previous work on visual selective attention in Attention Deficit Hyperactivity Disorder (ADHD) has utilised spatial search paradigms. This study compared ADHD to control children on a temporal search task using Rapid Serial Visual Presentation (RSVP). In addition, the effects of irrelevant singleton distractors on search performance were examined.

METHOD

In each condition, subjects reported the identity of a red letter 'probe' in a sequence of white letters which appeared one after the other at a central fixation point. The temporal position of the probe varied from an initial target, which was distinguished by surrounding asterisks. The target was reported in addition to the probe in condition 2, but not in the baseline condition 1. In a third condition, the initial target was not reported, but one of the asterisks appeared as a colour singleton on some trials.

RESULTS

All children displayed an 'attentional blink' with probe detection reduced when it appeared at close temporal relations relative to the target. This 'blink' reduced over time, and there were no group differences in the recovery of performance, although ADHD children made more errors overall. The ADHD group were also more vulnerable than controls to distraction from irrelevant singletons in condition 3.

CONCLUSION

Although the basic mechanisms of selective attention were not impaired in children with ADHD, these children appeared to require more resources to execute the task and were more vulnerable to distraction by irrelevant singletons, indicating deficits in the maintenance of attentional control.

Association of the paternally transmitted copy of common Valine allele of the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene with susceptibility to ADHD

Attention deficit hyperactivity disorder (ADHD) is a common, highly heritable, neurodevelopmental disorder with onset in early childhood. Genes involved in neuronal development and growth are, thus, important etiological candidates and brain-derived neurotrophic factor (BDNF), has been hypothesized to play a role in the pathogenesis of ADHD. BDNF is a member of the neurotrophin family and is involved in the survival and differentiation of dopaminergic neurons in the developing brain (of relevance because drugs that block the dopamine transporter can be effective therapeutically). The common Val66Met functional polymorphism in the human BDNF gene (rs 6265) was genotyped in a collaborative family-based sample of 341 white UK or Irish ADHD probands and their parents. We found evidence for preferential transmission of the valine (G) allele of BDNF (odds ratio, OR=1.6, P=0.02) with a strong paternal effect (paternal transmissions: OR=3.2, P=0.0005; maternal transmissions: OR=1.00; P=1.00). Our findings support the hypothesis that BDNF is involved in the pathogenesis of ADHD. The transmission difference between parents raises the possibility that an epigenetic process may be involved.

The scientific foundation for understanding attention-deficit/hyperactivity disorder as a valid psychiatric disorder

Continued questioning of the validity of a diagnosis of attention-deficit/hyperactivity disorder (ADHD) has created uncertainties about its management in the minds of many clinicians and the public. Inaccurate beliefs about the validity of ADHD hinder the clinical care of many ADHD patients and lead to confusion about the need to seek out or accept treatment. Critics describe ADHD as a diagnosis used to label difficult children who are not ill but whose behavior is at the extreme end of normal. They further contend that, far from having a biological basis, ADHD results from poor parenting and ineffective teaching practices. Such attitudes do much to further stigmatize patients and their families and increase the burden of this debilitating condition. This review attempts to address these challenges by presenting evidence to show that ADHD meets the criteria for a valid psychiatric diagnosis. Not only does it cause specific disabling symptoms that frequently persist into adulthood, but many studies show it has a biological basis and a characteristic response to treatment. Such data support the idea that ADHD is a valid diagnostic category.