BACKGROUND: DSM-IV specifies three ADHD subtypes; the combined, the hyperactive-impulsive and the inattentive. Little is known about the developmental relationships underlying these subtypes. The objective of this study was to describe the development of parent-reported hyperactivity-impulsivity and inattention symptoms from childhood to adolescence and to study their associations with genetic factors, family risk, and later adjustment problems in early adulthood. METHOD: Data in this study comes from 1,450 twin pairs participating in a population-based, longitudinal twin study. Developmental trajectories were defined using parent-ratings of hyperactivity-impulsivity and inattention symptoms at age 8-9, 13-14, and 16-17. Twin methods were used to explore genetic influences on trajectories. Family risk measures included low socioeconomic status, large family size and divorce. Self-ratings of externalizing and internalizing problems in early adulthood were used to examine adjustment problems related to the different trajectory combinations. RESULTS: We found two hyperactivity-impulsivity trajectories (low, high/decreasing) and two inattention trajectories (low, high/increasing). Twin modeling revealed a substantial genetic component underlying both the hyperactivity-impulsivity and the inattention trajectory. Joint trajectory analyses identified four groups of adolescents with distinct developmental patterns of hyperactivity-impulsivity and inattention: a low/low group, a primarily hyperactive, a primarily inattentive and a combined (high/high) trajectory type. These trajectory combinations showed discriminant relations to adjustment problems in early adulthood. The hyperactive, inattentive and combined trajectory subtypes were associated with higher rates of family risk environments compared to the low/low group. CONCLUSION: Study results showed that for those on a high trajectory, hyperactivity decreased whereas inattention increased. The combinations of these trajectories lend developmental insight into how children shift from (i) a combined to inattentive subtype, and (ii) a hyperactive-impulsive to a combined subtype. This study suggests that ADHD subtypes cannot be viewed as discrete and stable categories.
BACKGROUND: DSM-IV specifies three ADHD subtypes; the combined, the hyperactive-impulsive and the inattentive. Little is known about the developmental relationships underlying these subtypes. The objective of this study was to describe the development of parent-reported hyperactivity-impulsivity and inattention symptoms from childhood to adolescence and to study their associations with genetic factors, family risk, and later adjustment problems in early adulthood. METHOD: Data in this study comes from 1,450 twin pairs participating in a population-based, longitudinal twin study. Developmental trajectories were defined using parent-ratings of hyperactivity-impulsivity and inattention symptoms at age 8-9, 13-14, and 16-17. Twin methods were used to explore genetic influences on trajectories. Family risk measures included low socioeconomic status, large family size and divorce. Self-ratings of externalizing and internalizing problems in early adulthood were used to examine adjustment problems related to the different trajectory combinations. RESULTS: We found two hyperactivity-impulsivity trajectories (low, high/decreasing) and two inattention trajectories (low, high/increasing). Twin modeling revealed a substantial genetic component underlying both the hyperactivity-impulsivity and the inattention trajectory. Joint trajectory analyses identified four groups of adolescents with distinct developmental patterns of hyperactivity-impulsivity and inattention: a low/low group, a primarily hyperactive, a primarily inattentive and a combined (high/high) trajectory type. These trajectory combinations showed discriminant relations to adjustment problems in early adulthood. The hyperactive, inattentive and combined trajectory subtypes were associated with higher rates of family risk environments compared to the low/low group. CONCLUSION: Study results showed that for those on a high trajectory, hyperactivity decreased whereas inattention increased. The combinations of these trajectories lend developmental insight into how children shift from (i) a combined to inattentive subtype, and (ii) a hyperactive-impulsive to a combined subtype. This study suggests that ADHD subtypes cannot be viewed as discrete and stable categories.
Authors: Zeynep Yilmaz; Kristin N Javaras; Jessica H Baker; Laura M Thornton; Paul Lichtenstein; Cynthia M Bulik; Henrik Larsson Journal: J Adolesc Health Date: 2017-08 Impact factor: 5.012
Authors: Katelijne van Emmerik-van Oortmerssen; Geurt van de Glind; Maarten W J Koeter; Steve Allsop; Marc Auriacombe; Csaba Barta; Eli Torild H Bu; Yuliya Burren; Pieter-Jan Carpentier; Susan Carruthers; Miguel Casas; Zsolt Demetrovics; Geert Dom; Stephen V Faraone; Melina Fatseas; Johan Franck; Brian Johnson; Máté Kapitány-Fövény; Sharlene Kaye; Maija Konstenius; Frances R Levin; Franz Moggi; Merete Møller; J Antoni Ramos-Quiroga; Arild Schillinger; Arvid Skutle; Sofie Verspreet; Wim van den Brink; Robert A Schoevers Journal: Addiction Date: 2013-11-20 Impact factor: 6.526
Authors: Julia Rachel S E Mazza; Michel Boivin; Richard E Tremblay; Gregory Michel; Julie Salla; Jean Lambert; Maria Victoria Zunzunegui; Sylvana M Côté Journal: Soc Psychiatry Psychiatr Epidemiol Date: 2016-06-20 Impact factor: 4.328