The relation between attention deficit hyperactivity disorder and substance abuse: what role does conduct disorder play?

This paper presents a comprehensive review of the literature examining the relation between childhood attention deficit hyperactivity disorder (ADHD) and substance abuse. A number of researchers have statistically controlled for conduct disorder (CD) when examining the ADHD-substance-abuse relation. These studies have generally found that the ADHD-substance-abuse relation disappears when the high overlap between ADHD and CD is taken into account. On this basis, one may conclude that ADHD is unimportant to substance abuse. However, there is some evidence from both empirical studies and related fields that ADHD and CD may interact to afford a higher risk for substance abuse than may either disorder alone. Thus, ADHD appears to be important to substance abuse in that it interacts with CD to increase the risk. This paper calls for more research that directly examines the joint effects of ADHD and CD on risk for substance abuse. There is also a need for more research that examines gender differences, and mechanisms of the relations among ADHD, CD, and substance abuse.