TY - JOUR
T1 - Genetic associations between the ADHD symptom dimensions and Cloninger's temperament dimensions in adult twins
AU - Merwood, Andrew
AU - Asherson, Philip
AU - Larsson, Henrik
N1 - Copyright © 2012 Elsevier B.V. and ECNP. All rights reserved.
PY - 2013/6
Y1 - 2013/6
N2 - Previous studies have identified phenotypic associations between Cloninger's temperament dimensions and the symptoms of attention deficit hyperactivity disorder (ADHD) in adults. However the underlying aetiology of these associations remains unclear. We investigate the extent to which genetic and environmental influences contribute to the relationship between temperament and ADHD, examining the ADHD symptoms of inattention (IA) and hyperactivity/impulsivity (HI) separately. Participants were 886 adult twin pairs aged 19-20 years. ADHD symptoms of IA and HI were measured using a DSM-IV based rating scale. Temperament was measured using Cloninger's Temperament and Character Inventory (TCI), across four dimensions: novelty seeking (NS), harm avoidance (HA), reward dependence (RD) and persistence (PS). The twin method was used to decompose phenotypic variance/covariance among these variables into genetic and environmental components. We found that NS was genetically associated with both ADHD symptom dimensions (IA and HI), but that HA was genetically associated with IA only. There was also some evidence of genetic association between PS, IA and HI. These findings suggest that unique profiles of temperament are genetically related to the two ADHD symptom dimensions in adults. Further work is now needed to elucidate the mechanisms that underlie both the combined and separate symptom factor domains of ADHD.
AB - Previous studies have identified phenotypic associations between Cloninger's temperament dimensions and the symptoms of attention deficit hyperactivity disorder (ADHD) in adults. However the underlying aetiology of these associations remains unclear. We investigate the extent to which genetic and environmental influences contribute to the relationship between temperament and ADHD, examining the ADHD symptoms of inattention (IA) and hyperactivity/impulsivity (HI) separately. Participants were 886 adult twin pairs aged 19-20 years. ADHD symptoms of IA and HI were measured using a DSM-IV based rating scale. Temperament was measured using Cloninger's Temperament and Character Inventory (TCI), across four dimensions: novelty seeking (NS), harm avoidance (HA), reward dependence (RD) and persistence (PS). The twin method was used to decompose phenotypic variance/covariance among these variables into genetic and environmental components. We found that NS was genetically associated with both ADHD symptom dimensions (IA and HI), but that HA was genetically associated with IA only. There was also some evidence of genetic association between PS, IA and HI. These findings suggest that unique profiles of temperament are genetically related to the two ADHD symptom dimensions in adults. Further work is now needed to elucidate the mechanisms that underlie both the combined and separate symptom factor domains of ADHD.
U2 - 10.1016/j.euroneuro.2012.10.003
DO - 10.1016/j.euroneuro.2012.10.003
M3 - Article
C2 - 23122641
SN - 0924-977X
VL - 23
SP - 416
EP - 425
JO - European Neuropsychopharmacology
JF - European Neuropsychopharmacology
IS - 6
ER -