Increased Risk of Smoking in Female Adolescents Who Had Childhood ADHD

Objective:This study examined the effects of childhood attention deficit hyperactivity disorder (ADHD) symptoms, both inattention and hyperactivity-impulsivity, on the development of smoking in male and female adolescents.Method:Twin difference methods were used to control for shared genetic and environmental confounders in three population-based, same-sex twin samples (N=3,762; 64% monozygotic). One cohort oversampled female adolescents with ADHD beginning in childhood. Regressions of childhood inattentive and hyperactive-impulsive symptoms were conducted to predict smoking outcomes by age 17. ADHD effects were divided into those shared between twins in the pair and those nonshared, or different within pairs.Results:Adolescents who had more severe ADHD symptoms as children were more likely to initiate smoking and to start smoking younger. The association of ADHD symptoms with daily smoking, number of cigarettes per day, and nicotine dependence was greater in females than in males. Monozygotic female twin...