Nuria Gómez-Barros

Multicenter Analysis of the SLC6A3/DAT1 VNTR Haplotype in Persistent ADHD Suggests Differential Involvement of the Gene in Childhood and Persistent ADHD

Attention deficit/hyperactivity disorder (ADHD) is one of the most common neuropsychiatric disorders with a worldwide prevalence around 4–5% in children and 1–4% in adults. Although ADHD is highly heritable and familial risk may contribute most strongly to the persistent form of the disorder, there are few studies on the genetics of ADHD in adults. In this paper, we present the first results of the International Multicentre Persistent ADHD Genetics CollaboraTion (IMpACT) that has been set up with the goal of performing research into the genetics of persistent ADHD. In this study, we carried out a combined analysis as well as a meta-analysis of the association of the SLC6A3/DAT1 gene with persistent ADHD in 1440 patients and 1769 controls from IMpACT and an earlier report. DAT1, encoding the dopamine transporter, is one of the most frequently studied genes in ADHD, though results have been inconsistent. A variable number tandem repeat polymorphism (VNTR) in the 3′-untranslated region (UTR) of the gene and, more recently, a haplotype of this VNTR with another VNTR in intron 8 have been the target of most studies. Although the 10/10 genotype of the 3′-UTR VNTR and the 10-6 haplotype of the two VNTRs are thought to be risk factors for ADHD in children, we found the 9/9 genotype and the 9-6 haplotype associated with persistent ADHD. In conclusion, a differential association of DAT1 with ADHD in children and in adults might help explain the inconsistencies observed in earlier association studies. However, the data might also imply that DAT1 has a modulatory rather than causative role in ADHD.

Association Study of 10 Genes Encoding Neurotrophic Factors and Their Receptors in Adult and Child Attention-Deficit/Hyperactivity Disorder

BACKGROUND Attention-deficit/hyperactivity disorder (ADHD) is a common childhood-onset psychiatric disorder that often persists into adolescence and adulthood and is characterized by inappropriate levels of inattention, hyperactivity, and/or impulsivity. Genetic and environmental factors are believed to be involved in the continuity of the disorder as well as in changes in ADHD symptomatology throughout life. Neurotrophic factors (NTFs), which participate in neuronal survival and synaptic efficiency, are strong candidates to contribute to the neuroplasticity changes that take place in the human central nervous system during childhood, adolescence, and early adulthood and might be involved in the genetic predisposition to ADHD. METHODS We performed a population-based association study in 546 ADHD patients (216 adults and 330 children) and 546 gender-matched unrelated control subjects with 183 single nucleotide polymorphisms covering 10 candidate genes that encode four neurotrophins (NGF, BDNF, NTF3, and NTF4/5), a member of the cytokine family of NTFs (CNTF), and their receptors (NTRK1, NTRK2, NTRK3, NGFR, and CNTFR). RESULTS The single-marker and haplotype-based analyses provided evidence of association between CNTFR and both adulthood (p = .0077, odds ratio [OR] = 1.38) and childhood ADHD (p = 9.1e-04, OR = 1.40) and also suggested a childhood-specific contribution of NTF3 (p = 3.0e-04, OR = 1.48) and NTRK2 (p = .0084, OR = 1.52) to ADHD. CONCLUSIONS Our data suggest that variations in NTFs might be involved in the genetic susceptibility to ADHD, support the contribution of the CNTFR locus as a predisposition factor for the disorder, and suggest that NTF3 and NTRK2 might be involved in the molecular basis of the age-dependent changes in ADHD symptoms throughout life span.

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.

Psychoeducation for adults with attention deficit hyperactivity disorder vs. cognitive behavioral group therapy: a randomized controlled pilot study.

Abstract The aim of the present study was to assess the efficacy of psychoeducation as compared with cognitive behavioral group therapy in adults with attention deficit hyperactivity disorder (ADHD) who still had significant symptoms and were in pharmacological treatment. This is the first study on psychoeducation in adults with ADHD. Thirty-two individuals were randomized to two treatment conditions: 15 were in the psychoeducation group and 11 were in the cognitive behavioral group therapy. A total of 30 completed treatment, and 26 completed the follow-up assessments. The results indicated that both treatments were associated with statistically significant improvements on inattention, hyperactivity, impulsivity, and self-esteem. The patients in both groups showed a decrease in anxiety symptoms and obtained significantly lower scores in depression. Measures on functional impairment showed statistically significant differences on improved quality of life and on lower global severity as perceived in self-report and assessed by clinician report. Psychoeducation demonstrated to be an effective treatment in reducing ADHD core symptoms.

Validez de criterio y concurrente de la versión española de la Conners Adult ADHD Diagnostic Interview for DSM-IV

INTRODUCTION Attention deficit hyperactivity disorder (ADHD) is a common neuropsychiatric disorder in adulthood. Its diagnosis requires a retrospective evaluation of ADHD symptoms in childhood, the continuity of these symptoms in adulthood, and a differential diagnosis. For these reasons, diagnosis of ADHD in adults is a complex process which needs effective diagnostic tools. AIM To analyse the criterion validity of the CAADID semi-structured interview, Spanish version, and the concurrent validity compared with other ADHD severity scales. METHODS An observational case-control study was conducted on 691 patients with ADHD. They were out-patients treated in a program for adults with ADHD in a hospital. RESULTS A sensitivity of 98.86%, specificity 67.68%, positive predictive value 90.77% and a negative predictive value 94.87% were observed. Diagnostic precision was 91.46%. The kappa index concordance between the clinical diagnostic interview and the CAADID was 0.88. Good concurrent validity was obtained, the CAADID correlated significantly with WURS scale (r=0.522, P<.01), ADHD Rating Scale (r=0.670, P<.0.1) and CAARS (self-rating version; r=0.656, P<.01 and observer-report r=0.514, P<.01). CONCLUSION CAADID is a valid and useful tool for the diagnosis of ADHD in adults for clinical, as well as for research purposes.

Personality profile of adult ADHD: the alternative five factor model.

Attention-deficit/hyperactivity disorder (ADHD) is one of the most frequently diagnosed disorders in childhood affecting around 3% to 5% of adults worldwide. Most of the studies have been carried out using the Five Factor Model (FFM). Given the value and importance of describing adult ADHD in terms of general personality structure for a better conceptualization of this disorder, this study contributes adding new data on an Alternative Five Factor Model (AFFM) of personality. The aim of the present study is twofold: To assess the personality profile of adults with ADHD under the AFFM perspective, and to test the discriminant validity of the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ) in differentiating ADHD subjects vs. normal range controls. A sample of 217 adults (64% male) meeting ADHD diagnosis (DSM-IV) was paired by age and sex with 434 normal-range controls. Logistic regression analysis showed that high scores on Neuroticism-Anxiety, Impulsivity and General Activity, and low on Work Activity were the most powerful predictors of being endorsed with an ADHD diagnosis. Results may suggest refinements in the personality assessment of ADHD as it seems that the ZKPQ provides more specific subscales for the description and conceptualization of this disorder.

Emotional lability: The discriminative value in the diagnosis of attention deficit/hyperactivity disorder in adults

OBJECTIVE The aim of this study is to assess the discriminative value of emotional lability (EL) in the diagnosis of adults with ADHD. METHODS A group of adults who met ADHD DSM-IV diagnostic criteria (n=589), a clinical control group (n=138) and a community control group (n=98) were compared in EL scores. SCID-I, SCID-II and CAADID were used to select subjects. The specific subscale on EL of the Conners Adult ADHD Rating Scale (CAARS) was used to evaluate EL. RESULTS An analysis of the covariance was carried out in order to explore the association between EL, ADHD and comorbidity. The group factor (ADHD, clinical or community group) and the comorbidity factor (presence or absence of other psychiatric disorders different from ADHD) showed to be significant on EL intensity (group: F=81.78 p=0.000; comorbidity: F=25.48 p=0.000). However, no significant differences were found in the group × comorbidity interaction (F=1.006, p=0.366). EL showed a sensitivity of 87.1% and a specificity of 46.6% in discriminating between ADHD patients and subjects with other psychiatric disorders. CONCLUSION EL is specifically related to ADHD and this association is not explained for the presence of other psychiatric disorders. The presence of comorbid disorders is only related to a major intensity of EL.