title: Childhood attention-deficit/hyperactivity disorder symptoms and the development of adolescent alcohol problems: A prospective, population-based study of Swedish twins.
abstract: Children with attention-deficit/hyperactivity disorder (ADHD) are at increased risk of problematic alcohol and other substance use in adolescence. This study used data from an ongoing, prospective, population-based twin study of Swedish children and adolescents to evaluate the extent to which the association between ADHD symptoms and alcohol problems reflects a unique source of genetic or environmental risk related to ADHD versus a broader predisposition to youth externalizing behavior. We used all available data from same-sex monozygotic (MZ) and dizygotic (DZ) twins on ADHD symptoms in childhood (age 9/12; N = 15,549) and alcohol problems in late adolescence (age 18; N = 2,564). Consistent with prior longitudinal studies, the phenotypic association between hyperactive/impulsive ADHD symptoms and alcohol problems was small in magnitude, whereas the association for inattentive symptoms was even weaker. Additive genetic influences explained 99.8% of the association between hyperactive/impulsive symptoms and alcohol problems. Furthermore, we found that the genetic risk specifically associated with hyperactive/impulsive symptoms was attenuated when estimated in the context of externalizing behavior liability during childhood, of which ADHD symptoms were specific expressions. In sensitivity analyses exploring hyperactivity in mid-adolescence, we found a similar pattern of genetic associations. These results are consistent with previous findings of genetically driven overlap in the etiology of ADHD and problematic alcohol use. At least some of this co-occurrence may result from a general predisposition to externalizing behaviors in youth. © 2015 Wiley Periodicals, Inc.
authors.affiliation: Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana. quinnp@indiana.edu.
authors.forename: Patrick D
authors.initials: PD
authors.lastname: Quinn
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Pettersson
authors.affiliation: Gillberg Neuropsychiatry Centre, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Lundström
authors.affiliation: Department of Psychiatry and Neurochemistry, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Anckarsäter
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Niklas
authors.initials: N
authors.lastname: Långström
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Clara Hellner
authors.initials: CH
authors.lastname: Gumpert
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Larsson
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Paul
authors.initials: P
authors.lastname: Lichtenstein
authors.affiliation: Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana.
authors.forename: Brian M
authors.initials: BM
authors.lastname: D'Onofrio
mesh_terms: D000293:Adolescent; D000428:Alcohol Drinking / Q000235:genetics* / Q000523:psychology; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications* / Q000209:etiology / Q000235:genetics*; D002648:Child; D019955:Conduct Disorder / Q000523:psychology; D004777:Environment; D005260:Female; D059647:Gene-Environment Interaction; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D019966:Substance-Related Disorders / Q000209:etiology / Q000235:genetics; D013548:Sweden; D014427:Twins / Q000235:genetics
keywords: ADHD; behavioral genetics; externalizing; neurodevelopmental problems; substance misuse