Background: The externalising disorders conduct disorder (CD) and ADHD occur frequently in patients suffering from substance use disorders. These disorders play an important role in the onset and development of addiction.
Aim: To examine the influence of CD and ADHD on the current problems and the psychiatric comorbidity of patients with a chronic addiction.
Method: A group of 193 opiate-addicted patients receiving methadone maintenance treatment were evaluated extensively in the following areas: functioning, quality of life, psychiatric comorbidity (including CD and ADHD) and comorbid addictions. Standardised interviews were used to check for the presence of CD and ADHD.
Results: A history of CD was demonstrated in the majority of participants (60.1%). Persistent ADHD was ascertained in 24.9%. Participants with CD and/or ADHD had a more severe addiction, characterised by more psychiatric comorbidity, more serious dysfunctioning and reduced quality of life. A history of CD predisposed patients particularly to antisocial behaviour and personality disorders. ADHD increased the risk of psychiatric comorbidity.
Conclusion: Psychiatric comorbidity is part and parcel of addiction and reduces the quality of life of addicted patients. Behaviour problems in childhood play a major role in the development of severe addictions. Although CD is the biggest risk factor, the combination of ADHD with CD increases this risk, possibly through increased vulnerability to further psychiatric comorbidity.