A multicentre randomized controlled trial on trans-generational attention deficit/hyperactivity disorder (ADHD) in mothers and children (AIMAC): an exploratory analysis of predictors and moderators of treatment outcome.

OBJECTIVE: We examined predictors and moderators of treatment outcome in mothers and children diagnosed with ADHD in a large multicentre RCT. METHOD: In total, 144 mother-child dyads with ADHD were randomly assigned to either a maternal ADHD treatment (group psychotherapy and open methylphenidate medication, TG) or to a control treatment (individual counselling without psycho- or pharmacotherapy, CG). After maternal ADHD treatment, parent-child training (PCT) for all mother-child dyads was added. The final analysis set was based on 123 dyads with completed primary outcome assessments (TG: n = 67, CG: n = 56). The primary outcome was the change in each child's externalizing symptoms. Multiple linear regression analyses were performed. RESULTS: The severity of the child's externalizing problem behaviour in the family at baseline predicted more externalizing symptoms in the child after PCT, independent of maternal treatment. When mothers had a comorbid depression, TG children showed more externalizing symptoms after PCT than CG children of depressive mothers. No differences between the treatment arms were seen in the mothers without comorbid depression. CONCLUSIONS: Severely impaired mothers with ADHD and depressive disorder are likely to need additional disorder-specific treatment for their comorbid psychiatric disorders to effectively transfer the contents of the PCT to the home situation (CCTISRCTN73911400).

Sex- and Subtype-Related Differences in the Comorbidity of Adult ADHDs.

OBJECTIVE: Comorbidity in adult ADHD (aADHD) has been investigated in a large number of studies using varying research approaches with divergent results. In contrast, there is limited information about sex- or subtype-related differences from studies with small sample size. METHOD: A large sample of 910 individuals (458 males, 452 females) affected with aADHD was recruited at a tertiary referral center. All probands underwent a four-step procedure for diagnosing aADHD, including the Structured Clinical Interview of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) Axis I disorders to assess comorbidity. This study will provide additional information regarding the co-morbidity of Axis I disorders in the currently largest clinical referral sample. However, the main objective of this study is to gain information about sex- or subtype-related differences. RESULTS: Affected females show higher rates of mood (61% vs. 49%), anxiety (32% vs. 22%), and eating disorders (16% vs. 1%) than affected males, while substance use disorders were more frequent in affected males (45% vs. 29%), which mirrors sex differences in prevalence in the general population. There were hardly any relevant differences in comorbidities between subtypes, with the exception of the inattentive subtype having an especially low prevalence of panic disorder. Comorbidity in general and substance use disorders in particular, but not sex or subtype, were highly predictive of lower psychosocial status. CONCLUSION: Sex-related differences in the comorbidity of aADHD are more pronounced than subtype-related differences.

Sex- and Subtype-Related Differences of Personality Disorders (Axis II) and Personality Traits in Persistent ADHD.

OBJECTIVE: Despite growing awareness of adult ADHD and its comorbidity with personality disorders (PDs), little is known about sex- and subtype-related differences. METHOD: In all, 910 patients (452 females, 458 males) affected with persistent adult ADHD were assessed for comorbid PDs with the Structured Clinical Interview of DSM-IV and for personality traits with the revised NEO personality inventory, and the Tridimensional Personality Questionnaire. RESULTS: The most prevalent PDs were narcissistic PD in males and histrionic PD in females. Affected females showed higher Neuroticism, Openness to Experience, and Agreeableness scores as well as Harm Avoidance and Reward Dependence scores. Narcissistic PD and antisocial PD have the highest prevalence in the H-type, while Borderline PD is more frequent in the C-type. CONCLUSION: Sex- and subtype-related differences in Axis II disorder comorbidity as well as impairment-modifying personality traits have to be taken into account in epidemiological studies of persistent ADHD.

Effects of Group Psychotherapy, Individual Counseling, Methylphenidate, and Placebo in the Treatment of Adult Attention-Deficit/Hyperactivity Disorder: A Randomized Clinical Trial.

IMPORTANCE: Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder with high prevalence in adulthood. There is a recognized need to assess the efficacy of psychotherapy in adult ADHD. OBJECTIVE: To evaluate the efficacy of cognitive behavioral group psychotherapy (GPT) compared with individual clinical management (CM) and that of methylphenidate hydrochloride compared with placebo. DESIGN, SETTING, AND PARTICIPANTS: Prospective, multicenter, randomized clinical trial of 18- to 58-year-old outpatients with ADHD from 7 German study centers. Patients were recruited between January 2007 and August 2010, treatment was finalized in August 2011, and final follow-up assessments occurred in March 2013. INTERVENTIONS: Sessions of GPT and CM were held weekly for the first 12 weeks and monthly thereafter (9 months). Patients received either methylphenidate or placebo for 1 year. MAIN OUTCOMES AND MEASURES: The primary outcome was the change in the ADHD Index of the Conners Adult ADHD Rating Scale from baseline to the end of the 3-month intensive treatment (blinded observer ratings). Secondary outcomes included ADHD ratings after 1 year, blinded observer ratings using the Clinical Global Impression Scale, and self-ratings of depression. RESULTS: Among 1480 prescreened patients, 518 were assessed for eligibility, 433 were centrally randomized, and 419 were analyzed as randomized. After 3 months, the ADHD Index all-group baseline mean of 20.6 improved to adjusted means of 17.6 for GPT and 16.5 for CM, with no significant difference between groups. Methylphenidate (adjusted mean, 16.2) was superior to placebo (adjusted mean, 17.9) (difference, -1.7; 97.5% CI, -3.0 to -0.4; P = .003). After 1 year, treatment effects remained essentially stable. Descriptive analyses showed that methylphenidate was superior to placebo in patients assigned to GPT (difference, -1.7; 95% CI, -3.2 to -0.1; P = .04) or CM (difference, -1.7; 95% CI, -3.3 to -0.2; P = .03). Regarding depression, no significant differences were found. In contrast, GPT was superior to CM for all visits in the Clinical Global Impression global assessment of effectiveness. CONCLUSION AND RELEVANCE: Highly structured group intervention did not outperform individual CM with regard to the primary outcome. Psychological interventions resulted in better outcomes during a 1-year period when combined with methylphenidate as compared with placebo. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN54096201.

Does intensive multimodal treatment for maternal ADHD improve the efficacy of parent training for children with ADHD? A randomized controlled multicenter trial.

BACKGROUND: This is the first randomized controlled multicenter trial to evaluate the effect of two treatments of maternal attention-deficit hyperactivity disorder (ADHD) on response to parent-child training targeting children's external psychopathology. METHODS: Mother-child dyads (n = 144; ADHD according to DSM-IV; children: 73.5% males, mean age 9.4 years) from five specialized university outpatient units in Germany were centrally randomized to multimodal maternal ADHD treatment [group psychotherapy plus open methylphenidate medication; treatment group (TG): n = 77] or to clinical management [supportive counseling without psychotherapy or psychopharmacotherapy; control group (CG): n = 67]. After 12 weeks, the maternal ADHD treatment was supplemented by individual parent-child training for all dyads. The primary outcome was a change in the children's externalizing symptom scores (investigator blinded to the treatment assignment) from baseline to the end of the parent-child training 6 months later. Maintenance therapy continued for another 6 months. An intention-to-treat analysis was performed within a linear regression model, controlling for baseline and center after multiple imputations of missing values. RESULTS: Exactly, 206 dyads were assessed for eligibility, 144 were randomized, and 143 were analyzed (TG: n = 77; CG: n = 66). After 6 months, no significant between-group differences were found in change scores for children's externalizing symptoms (adjusted mean TG-mean CG=1.1, 95% confidence interval -0.5-2.7; p = .1854), although maternal psychopathology improved more in the TG. Children's externalizing symptom scores improved from a mean of 14.8 at baseline to 11.4 (TG) and 10.3 (CG) after 6 months and to 10.8 (TG) and 10.1 (CG) after 1 year. No severe harms related to study treatments were found, but adverse events were more frequent in TG mothers than in CG mothers. CONCLUSIONS: The response in children's externalizing psychopathology did not differ between maternal treatment groups. However, multimodal treatment was associated with more improvement in maternal ADHD. Child and maternal treatment gains were stable (CCT-ISRCTN73911400).

Case-control genome-wide association study of persistent attention-deficit hyperactivity disorder identifies FBXO33 as a novel susceptibility gene for the disorder.

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder with high heritability. At least 30% of patients diagnosed in childhood continue to suffer from ADHD during adulthood and genetic risk factors may play an essential role in the persistence of the disorder throughout lifespan. To date, genome-wide association studies (GWAS) of ADHD have been completed in seven independent datasets, six of which were pediatric samples and one on persistent ADHD using a DNA-pooling strategy, but none of them reported genome-wide significant associations. In an attempt to unravel novel genes for the persistence of ADHD into adulthood, we conducted the first two-stage GWAS in adults with ADHD. The discovery sample included 607 ADHD cases and 584 controls. Top signals were subsequently tested for replication in three independent follow-up samples of 2104 ADHD patients and 1901 controls. None of the findings exceeded the genome-wide threshold for significance (PGC<5e-08), but we found evidence for the involvement of the FBXO33 (F-box only protein 33) gene in combined ADHD in the discovery sample (P=9.02e-07) and in the joint analysis of both stages (P=9.7e-03). Additional evidence for a FBXO33 role in ADHD was found through gene-wise and pathway enrichment analyses in our genomic study. Risk alleles were associated with lower FBXO33 expression in lymphoblastoid cell lines and with reduced frontal gray matter volume in a sample of 1300 adult subjects. Our findings point for the first time at the ubiquitination machinery as a new disease mechanism for adult ADHD and establish a rationale for searching for additional risk variants in ubiquitination-related genes.

Internalizing and externalizing behavior in adult ADHD.

Although there are many studies available investigating internalizing and externalizing behavior in childhood and adolescent manifestations of attention-deficit/hyperactivity disorder, there is limited information about their relevance in adults featuring persistence of the disease. We examined a large sample of 910 adults affected with attention-deficit/hyperactivity disorders (AADHD) for internalizing and externalizing behavior. Regarding correlates of internalizing behavior, AADHD probands showed significantly higher scores of the anxiety- and depression-related personality traits Neuroticism and Harm Avoidance, compared with reference values. The lifetime comorbidity of depressive disorders, anxiety disorders, and anxious or fearful Cluster C personality disorders (PDs) is elevated in AADHD patients compared with general population. Regarding correlates of externalizing behavior, patients affected with AADHD show significantly lower scores of Conscientiousness and significantly higher scores of Novelty Seeking than the published German reference values. Emotional, dramatic, or erratic Cluster B PDs were most frequent in AADHD. Internalizing and externalizing behavior notably affected psychosocial status to a similar extent. The frequency of both internalizing and externalizing behavior in AADHD might reflect an underlying emotional regulation disorder.

A randomized controlled multicenter trial on the multimodal treatment of adult attention-deficit hyperactivity disorder: enrollment and characteristics of the study sample.

Adult ADHD is a frequent psychiatric disorder affecting relevant aspects of an individual's life. The aim of our study group was to carry out the first randomized controlled multicenter study to evaluate the effects of psychotherapy compared to clinical management in combination with psychopharmacological treatment with methylphenidate (MPH) or placebo (Plac) in a factorial four-arm design. Here, we present the enrollment procedure and description of adult ADHD patients recruited for the trial. Four hundred and thirty-three adult patients with ADHD were randomized at seven study sites in Germany to four treatment conditions: manualized dialectical-behavioral-therapy-based group psychotherapy (GPT) plus MPH or Plac, or clinical management (CM) including supportive counseling plus MPH or Plac with weekly sessions in the first 12 weeks and monthly sessions thereafter. Assessment for eligibility included standardized scales and instruments. After prescreening of 1,480 patients, 518 were evaluated for trial participation and 433 were randomized. The main reasons for prescreening failure were lack of interest in participating (n = 205), difficulties in meeting the time and effort requirements for participation (n = 186), and contraindications for psychopharmacological treatment with MPH (n = 194). The full analysis set (FAS) comprised 419 adult ADHD patients (mean age 35.2 years, males/females 1:1). Fifty-seven percent of the patients suffered from the combined ADHD subtype. Prevalence of at least one current or lifetime axis-I comorbidity was 66 %. Axis-II comorbidity rates was 18 % (patients with comorbid borderline and antisocial personality disorders were excluded). Our network was able to recruit an adult ADHD sample essentially comparable to community samples. A selection bias was created by excluding patients unable or unwilling to participate, or who had somatic and psychiatric contraindications for stimulant treatment (Current Controlled Trials ISRCTN54096201, FUNDING: Federal Ministry of Education and Research 01GV0606).

KCNIP4 as a candidate gene for personality disorders and adult ADHD.

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder in children with striking persistence into adulthood and a high co-morbidity with other psychiatric disorders, including personality disorders (PD). The 4p15.31 region was shown to be associated with ADHD in several genome wide association studies (GWAS). In the present study we also report association of the 4p15.31 locus with Cluster B and Cluster C PD as identified by a pooled genome-wide association study in 400 individuals suffering from PD. The gene coding for the Kv channel-interacting protein 4 (KCNIP4) is located in this region. KCNIP4 is an interaction partner of presenilin and plays a role in a negative feedback loop in the Wnt/ß-catenin pathway. Thus, we reasoned it to be a promising candidate gene for ADHD as well as for PD. To clarify the role of KCNIP4 in those disorders, we conducted candidate gene based association studies in 594 patients suffering from adult ADHD and 630 PD patients as compared to 974 healthy control individuals. In the adult ADHD sample, six single markers and one haplotype block revealed to be associated with disease (p values from 0.0079 to 0.049). Seven markers within the KCNIP4 gene showed an association with PD (p values from 0.0043 to 0.0437). The results of these studies suggest a role of KCNIP4 in the etiology of ADHD, PD and other co-morbid disorders.

A randomized controlled multicentre trial on the treatment for ADHD in mothers and children: enrolment and basic characteristics of the study sample.

Parental ADHD may be a significant barrier to a successful treatment for the child's ADHD. The objective of our randomized controlled trial was to evaluate whether the treatment for maternal ADHD improves the efficacy of a behavioural parent training for children's ADHD. Patient enrolment and a description of the full analysis set (FAS) of mother-child pairs with non-missing baseline data are presented. One hundred and forty-four mother-child pairs were randomized to two treatments for maternal ADHD: cognitive behavioural group psychotherapy plus open methylphenidate treatment or control treatment (supportive counselling). After 3 months of treatment for maternal ADHD, mother-child pairs participated in a behavioural parent-child training. Assessment for eligibility included standardized instruments. After pre-screening out of 444 mother-child pairs, 206 were evaluated for trial participation and 144 were randomized. The FAS was built up by 143 dyads (children: mean age 9.4 years, 73 % males; mothers: mean age: 38.3 years). Fifty-two per cent of the children and 66 % of the mothers had combined ADHD subtype. Current axis-I co-morbidity rates were 48 % in children and 31 % in mothers. Maternal axis-II co-morbidity was 20.1 %. Fifty-seven per cent of the mothers lived together with the father of the index-child, and 29 % were single mothers. Sixty-two per cent had part-time or full-time employment. There was a selection bias excluding mothers with lack of time and effort for participation and mothers affected by coexisting mental and physical illness. Nevertheless, for our trial we were able to collect a sample comparable to routine psychiatric outpatient settings (registration: CCT-ISRCTN73911400, funding: BMBF-01GV0605).

PPP2R2C as a candidate gene of a temperament and character trait-based endophenotype of ADHD.

There are several lines of evidence that the 4p16 region is a candidate locus of both attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder. None of the harbored candidate genes of this region were hitherto shown to be associated with ADHD despite promising functionality. One of the most promising candidate genes in this region is protein phosphatase 2, regulatory subunit B, gamma (PPP2R2C), which, however, thus far has not been assessed for a potential association with ADHD. A total of 513 in- and outpatients affected with adult ADHD and 536 controls as well as 170 nuclear families with 249 children affected with ADHD were genotyped for 35 SNPs, which tagged the promoter region, the 5' and 3' UTRs, and the exons of the PPP2R2C. Two independent samples provided evidence that the major G allele of rs16838844 increases risk toward ADHD. Allelic variations of PPP2R2C rs16838698 on the other hand might be associated with a variety of personality traits. There is evidence that allelic variation in PPP2R2C may be associated with a variety of personality traits and ADHD per se. Nevertheless, as all those conditions are comorbid, PPP2R2C might reflect a common underlying neurobiological risk factor.

Pilot study: potential transcription markers for adult attention-deficit hyperactivity disorder in whole blood.

Attention-deficit hyperactivity disorder (ADHD) is a common behavioural disorder that affects not only children and adolescents but also adults; however, diagnosis of adult ADHD is difficult because patients seem to have reduced externalized behaviour. ADHD is a multifactorial disorder in which many genes, all with small effects, are thought to cause the disorder in the presence of unfavourable environmental conditions. Therefore, in this pilot study, we explored the expression profile of a list of previously established candidate genes in peripheral blood samples from adult ADHD subjects (n = 108) and compared these results with those of healthy controls (n = 35). We demonstrate that combining the gene expression levels of dopamine transporter (SLC6A3), dopamine D5 receptor, tryptophan hydroxylase-1, and SNAP25 as predictors in a regression model resulted in sensitivity and specificity of over 80 % (ROC: max R(2) = 0.587, AUC = 0.917, P < 0.001, 95 % CI: 0.900-0.985). In conclusion, the combination of these four genes could represent a potential method for estimating risk and could be of diagnostic value for ADHD. Nevertheless, further investigation in a larger independent population including different subtypes of ADHD (inattentive, hyperactive, or combined type) patients is required to obtain more specific sets of biomarkers for each subtype as well as to differentiate between child, adolescent, and adulthood forms.

An association study of sequence variants in the forkhead box P2 (FOXP2) gene and adulthood attention-deficit/hyperactivity disorder in two European samples.

OBJECTIVES: Attention-deficit/hyperactivity disorder (ADHD) is a common psychiatric disorder manifesting as symptoms of inattention, hyperactivity, and/or impulsivity. Learning disabilities co-occur with ADHD in 20-30% of cases and this high co-occurrence raises the possibility of a common etiological background. Forkhead box P2 (FOXP2) encodes a transcription factor involved in speech and language impairment and in the control of the corticobasal ganglia circuits known to be relevant in ADHD, suggesting a possible role of FOXP2 in ADHD. Our aim was to carry out an association study between FOXP2 and adulthood ADHD. METHODS: We carried out a case-control association study in 643 adult ADHD patients and 619 controls from Germany and in 361 adult ADHD patients and 442 controls from Spain with 12 tagging single nucleotide polymorphisms covering the FOXP2 gene. RESULTS: The single-marker and multiple-marker analyses showed an association between FOXP2 and combined ADHD in the German cohort [rs12533005: P=0.0033; odds ratio=1.30 (1.09-1.56); rs12533005/rs1229761: P=4.1e-04; odds ratio=1.38 (1.15-1.66)]. These positive results, however, were not confirmed in the Spanish sample. CONCLUSION: Although these preliminary findings provide a tentative evidence for the contribution of FOXP2 to ADHD and suggest common genetic factors for this psychiatric disorder and learning disabilities, they should be interpreted with caution. Further studies in larger samples are needed to clarify the role of this transcription factor in ADHD.

DIRAS2 is associated with adult ADHD, related traits, and co-morbid disorders.

Several linkage analyses implicated the chromosome 9q22 region in attention deficit/hyperactivity disorder (ADHD), a neurodevelopmental disease with remarkable persistence into adulthood. This locus contains the brain-expressed GTP-binding RAS-like 2 gene (DIRAS2) thought to regulate neurogenesis. As DIRAS2 is a positional and functional ADHD candidate gene, we conducted an association study in 600 patients suffering from adult ADHD (aADHD) and 420 controls. Replication samples consisted of 1035 aADHD patients and 1381 controls, as well as 166 families with a child affected from childhood ADHD. Given the high degree of co-morbidity with ADHD, we also investigated patients suffering from bipolar disorder (BD) (n=336) or personality disorders (PDs) (n=622). Twelve single-nucleotide polymorphisms (SNPs) covering the structural gene and the transcriptional control region of DIRAS2 were analyzed. Four SNPs and two haplotype blocks showed evidence of association with ADHD, with nominal p-values ranging from p=0.006 to p=0.05. In the adult replication samples, we obtained a consistent effect of rs1412005 and of a risk haplotype containing the promoter region (p=0.026). Meta-analysis resulted in a significant common OR of 1.12 (p=0.04) for rs1412005 and confirmed association with the promoter risk haplotype (OR=1.45, p=0.0003). Subsequent analysis in nuclear families with childhood ADHD again showed an association of the promoter haplotype block (p=0.02). rs1412005 also increased risk toward BD (p=0.026) and cluster B PD (p=0.031). Additional SNPs showed association with personality scores (p=0.008-0.048). Converging lines of evidence implicate genetic variance in the promoter region of DIRAS2 in the etiology of ADHD and co-morbid impulsive disorders.

Cross-disorder analysis of bipolar risk genes: further evidence of DGKH as a risk gene for bipolar disorder, but also unipolar depression and adult ADHD.

Recently, several genome-wide association studies (GWAS) on bipolar disorder (BPD) suggested novel risk genes. However, only few of them were followed up and further, the specificity of these genes is even more elusive. To address these issues, we genotyped SNPs in ANK3, CACNA1C, CMTM8, DGKH, EGFR, and NPAS3, which were significantly associated with BPD in previous GWAS, in a sample of 380 BPD patients. Replicated SNPs were then followed up in patients suffering from unipolar depression (UPD; n=387) or adult attention-deficit/hyperactivity disorder (aADHD; n=535). While we could not confirm an association of ANK3, CACNA1C, and EGFR with BPD, 10 SNPs in DGKH, CMTM8, and NPAS3 were nominally associated with disease, with two DGKH markers surviving correction for multiple testing. When these were followed up in UPD and aADHD, seven DGKH SNPs were also associated with UPD, while one SNP each in NPAS3 and CMTM8 and four in DGKH were linked to aADHD. Furthermore, a DGKH haplotype consisting of rs994856/rs9525580/rs9525584 GAT was associated with all disorders tested, while the complementary AGC haplotype was protective. The corresponding haploblock spans a 27-kb region covering exons coding for amino acids 65-243, and thus might include functional variants yet to be identified. We demonstrate an association of DGKH with BPD, UPD, and aADHD by applying a two-stage design. These disorders share the feature of mood instability, so that this phenotype might be associated with genetic variation in DGKH.

Exploring DRD4 and its interaction with SLC6A3 as possible risk factors for adult ADHD: a meta-analysis in four European populations.

Attention-deficit hyperactivity disorder (ADHD) is a common behavioral disorder affecting about 4-8% of children. ADHD persists into adulthood in around 65% of cases, either as the full condition or in partial remission with persistence of symptoms. Pharmacological, animal and molecular genetic studies support a role for genes of the dopaminergic system in ADHD due to its essential role in motor control, cognition, emotion, and reward. Based on these data, we analyzed two functional polymorphisms within the DRD4 gene (120 bp duplication in the promoter and 48 bp VNTR in exon 3) in a clinical sample of 1,608 adult ADHD patients and 2,352 controls of Caucasian origin from four European countries that had been recruited in the context of the International Multicentre persistent ADHD CollaboraTion (IMpACT). Single-marker analysis of the two polymorphisms did not reveal association with ADHD. In contrast, multiple-marker meta-analysis showed a nominal association (P = 0.02) of the L-4R haplotype (dup120bp-48bpVNTR) with adulthood ADHD, especially with the combined clinical subtype. Since we previously described association between adulthood ADHD and the dopamine transporter SLC6A3 9R-6R haplotype (3'UTR VNTR-intron 8 VNTR) in the same dataset, we further tested for gene × gene interaction between DRD4 and SLC6A3. However, we detected no epistatic effects but our results rather suggest additive effects of the DRD4 risk haplotype and the SLC6A3 gene.

Olfactory and gustatory sensitivity in adults with attention-deficit/hyperactivity disorder.

Recently, research on olfactory functions in attention-deficit/hyperactivity disorder (ADHD) has become prominent, whereas gustation has never been investigated. Increased odor sensitivity was found in medication-naïve children with ADHD, but not in adult ADHD, which might be due to a dopaminergic dysregulation presumed to underlie this disorder. Taste sensitivity, in particular bitter sensitivity as a hereditary trait, also might be altered in ADHD. To examine olfactory and gustatory functions in adult ADHD patients, we assessed odor sensitivity by Sniffin' Sticks, taste sensitivity by taste strips, and bitter sensitivity by the one-solution test in women with ADHD (n = 12), Bulimia Nervosa (n = 12), and healthy control women (n = 12). Bulimia Nervosa as second patient group was included to control for effects of impulsivity. Preliminary results indicate that ADHD patients were significantly more often classified as tasters, i.e. perceived the bitter taste as more intense, compared to both bulimic patients and healthy controls. No group differences were found with regard to general odor and taste sensitivity. It is proposed that the higher frequency of tasters in ADHD patients might underlie a genetic variation of the bitter receptor-dependent signaling pathway associated with ADHD.

Evaluation of the efficacy and effectiveness of a structured disorder tailored psychotherapy in ADHD in adults: study protocol of a randomized controlled multicentre trial.

ADHD is a serious risk factor for co-occurring psychiatric disorders and negative psychosocial consequences in adulthood. Previous trials on psychotherapeutic concepts for adult ADHD are based on behavioural (cognitive behavioural and dialectical behavioural) psychotherapeutic approaches and showed significant effects. The aim of our study group (COMPAS) is to carry out a first randomized and controlled multicentre study to evaluate the effects of a disorder tailored psychotherapy in adult ADHD compared to clinical management in combination with psychopharmacological treatment or placebo. A total of 448 adults with ADHD according to DSM-IV will be treated at seven university sites in Germany. In a four-arm design, patients are randomized to a manualized dialectical behavioural therapy (DBT) based group programme plus methylphenidate or placebo or clinical management plus methylphenidate or placebo with weekly sessions in the first 12 weeks and monthly sessions thereafter. Therapists are graduated psychologists or physicians. Treatment integrity is established by independent supervision. Primary endpoint (ADHD symptoms measured by the Conners Adult Rating Scale) is rated by interviewers blind to the treatment allocation. Intention-to-treat analysis will be performed within a linear regression model (Current Controlled Trials ISRCTN54096201). The trial is funded by the German Federal Ministry of Research and Education (01GV0606) and is part of the German network for the treatment of ADHD in children and adults (ADHD-NET).

A gene-environment investigation on personality traits in two independent clinical sets of adult patients with personality disorder and attention deficit/hyperactive disorder.

While an interactive effect of genes with adverse life events is increasingly appreciated in current concepts of depression etiology, no data are presently available on interactions between genetic and environmental (G x E) factors with respect to personality and related disorders. The present study therefore aimed to detect main effects as well as interactions of serotonergic candidate genes (coding for the serotonin transporter, 5-HTT; the serotonin autoreceptor, HTR1A; and the enzyme which synthesizes serotonin in the brain, TPH2) with the burden of life events (#LE) in two independent samples consisting of 183 patients suffering from personality disorders and 123 patients suffering from adult attention deficit/hyperactivity disorder (aADHD). Simple analyses ignoring possible G x E interactions revealed no evidence for associations of either #LE or of the considered polymorphisms in 5-HTT and TPH2. Only the G allele of HTR1A rs6295 seemed to increase the risk of emotional-dramatic cluster B personality disorders (p = 0.019, in the personality disorder sample) and to decrease the risk of anxious-fearful cluster C personality disorders (p = 0.016, in the aADHD sample). We extended the initial simple model by taking a G x E interaction term into account, since this approach may better fit the data indicating that the effect of a gene is modified by stressful life events or, vice versa, that stressful life events only have an effect in the presence of a susceptibility genotype. By doing so, we observed nominal evidence for G x E effects as well as main effects of 5-HTT-LPR and the TPH2 SNP rs4570625 on the occurrence of personality disorders. Further replication studies, however, are necessary to validate the apparent complexity of G x E interactions in disorders of human personality.

Case-control study of six genes asymmetrically expressed in the two cerebral hemispheres: association of BAIAP2 with attention-deficit/hyperactivity disorder.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a childhood-onset neuropsychiatric disease that persists into adulthood in at least 30% of patients. There is evidence suggesting that abnormal left-right brain asymmetries in ADHD patients may be involved in a variety of ADHD-related cognitive processes, including sustained attention, working memory, response inhibition and planning. Although mechanisms underlying cerebral lateralization are unknown, left-right cortical asymmetry has been associated with transcriptional asymmetry at embryonic stages and several genes differentially expressed between hemispheres have been identified. METHODS: We selected six functional candidate genes showing at least 1.9-fold differential expression between hemispheres (BAIAP2, DAPPER1, LMO4, NEUROD6, ATP2B3, and ID2) and performed a case-control association study in an initial Spanish sample of 587 ADHD patients (270 adults and 317 children) and 587 control subjects. RESULTS: The single- and multiple-marker analysis provided evidence for a contribution of BAIAP2 to adulthood ADHD (p = .0026 and p = .0016, respectively). We thus tested BAIAP2 for replication in two independent adult samples from Germany (639 ADHD patients and 612 control subjects) and Norway (417 ADHD cases and 469 control subjects). While no significant results were observed in the Norwegian sample, we replicated the initial association between BAIAP2 and adulthood ADHD in the German population (p = .0062). CONCLUSIONS: Our results support the participation of BAIAP2 in the continuity of ADHD across life span, at least in some of the populations analyzed, and suggest that genetic factors potentially influencing abnormal cerebral lateralization may be involved in this disorder.