A Longitudinal Twin Study on the Association Between Inattentive and Hyperactive-Impulsive ADHD Symptoms

Abstract

DSM-IV distinguishes two symptom domains of attention deficit hyperactivity disorder (ADHD): inattentiveness and hyperactivity-impulsivity. The present study examines the aetiologies and developmental relations underlying the associations between inattentiveness and hyperactivity-impulsivity over time, based on a representative population sample from the United Kingdom of approximately 7,000 twin pairs. ADHD symptoms were assessed as continuous dimensions using the DSM-IV items from the Conners' Parent Rating Scale at two ages: middle childhood (age 1) and early adolescence (age 2). Quantitative genetic cross-lagged analyses showed that the association of the ADHD dimensions over time is influenced by stable as well as newly developing genetic factors. Moreover the longitudinal relationship between the ADHD dimensions appears to be unidirectional, with hyperactivity-impulsivity in middle childhood predicting the presence of inattentiveness in early adolescence, but not vice versa. Thus, hyperactivity-impulsivity may serve to exacerbate inattentiveness over time. Findings are discussed in the context of developmental changes in ADHD symptoms.

Review: changing (shared) heritability of ASD and ADHD across the lifespan

“…Several longitudinal twin studies on ADHD symptoms report that new, age-specific genetic effects influence ADHD symptoms in adolescence and adulthood, suggesting that ADHD symptoms are a developmentally complex phenotype characterized by both continuity and change across the life span [3,9,12,13,19]. In addition, only a modest overlap between longitudinal genetic effects underlying both symptom domains (inattention versus hyperactivity/impulsivity) appears present, suggesting it is necessary to study both separately.…”

Does the Environment Have an Enduring Effect on ADHD? A Longitudinal Study of Monozygotic Twin Differences in Children

“…Greven, Asherton, Rijsdijk, and Plomin (2011) analysed inattention and hyperactivity, separately, at ages 7 and 11. At age 11, for both phenotypes, ~70% of the environmental variance (including measurement error) was short-lived and specific to one time point.…”

Emerging Control and Disruptive Behavior Disorders During Early Childhood

“…Cognitive forms of control, and possibly effortful temperamental control, are typically viewed as developing slightly later due to their reliance on the prefrontal cortex and anterior cingulate gyrus and their facilitation of individual-driven influences on the environment (Casey et al, 2005; Nigg & Casey, 2005). In line with this idea, DBD symptoms such as ODD and hyperactivity-impulsivity, which are hypothesized to depend on affective control, typically peak early during development and then decline; whereas DBD symptoms such as inattention, that are believed to depend more on cognitive control, usually start later and are relatively stable (Greven, Asherson, Rijsdijk, & Plomin, 2011; Lahey, Pelham, Loney, Lee, & Willcutt, 2005). …”