The role of conduct disorder in the association between ADHD and alcohol use (disorder). Results from the Netherlands Mental Health Survey and Incidence Study-2.

BACKGROUND Much is unclear about the association between attention-deficit/hyperactivity disorder (ADHD) and alcohol use (disorder). Research on this subject is hindered by the role of conduct disorder (CD). We investigate whether (1) childhood ADHD is associated with higher prevalence and earlier onset of alcohol initiation, regular alcohol use and alcohol use disorder (AUD) (2) CD mediates or modifies this association. METHODS Data were derived from the baseline assessment of the Netherlands Mental Health Survey and Incidence Study-2, a general population study. ADHD and CD were assessed among respondents aged 18-44 (n=3309). ADHD, CD, and alcohol use (disorder) were assessed using the Composite International Diagnostic Interview 3.0. RESULTS Lifetime prevalence was 2.9% for ADHD, 5.6% for CD, 94.3% for alcohol initiation, 85.7% for regular alcohol use and 19.0% for AUD; mean ages of onset were 6.7, 11.5, 14.8, 16.7 and 19.2 years, respectively. After correction for gender and age, ADHD was associated with a higher prevalence of all three stages of alcohol use, but not with earlier onset of these stages. The association between ADHD and prevalence of AUD was fully explained by a mediating role of CD. CD did not modify the associations between ADHD and prevalence and onset of alcohol use (disorder). CONCLUSIONS The mediating role of CD in the association between ADHD and AUD suggests a developmental pathway from ADHD to CD and subsequent AUD. Early interventions in children with ADHD may prevent CD and subsequent onset of AUD.