Genetic and environmental influences on attention-deficit/hyperactivity disorder symptoms in Chinese adolescents: a longitudinal twin study

This study investigated changes of genetic and environmental influences and their contributions to the stability and change of ADHD symptoms of hyperactivity/impulsivity and inattention in Chinese adolescent twins. A prospective sample of 602 twin pairs (48% male) self-reported both DSM-IV ADHD symptom subscales three times at the approximate age of 12, 13, and 15  years. Longitudinal multivariate genetic analyses through structural equation modelling examined genetic and environmental contributions to the developmental course of ADHD symptoms. From early (time 1 and 2) to middle adolescence (time 3), both symptoms showed modest and non-significant genetic i nfluences that became substantial and significant, whereas shared environmental influences were substantial and significant and became modest and non-significant. The same genetic factors influenced ADHD symptoms throughout adolescence, while shared and non-shared environmental influences largely ca me from new emerging factors. In early adolescence, genetic factor contributed to the stability of inattention, whereas shared environmental factor contributed to the stability of hyperactivity/impulsivity. Genetic influences of ADHD tended to be smaller, whereas shared environmental influences tend ed to be larger in Chinese than in Western populations. Genetic factors played a large role in the stability of ADHD throughout adolescence, while shared and non-shared environment primarily contributed to its change. Findings hig...
Source: European Child and Adolescent Psychiatry - Category: Psychiatry Source Type: research