Stimulant use and symptoms of abuse/dependence: Epidemiology and associations with cannabis use-A twin study

There were moderate genetic influences on stimulant use and stimulant abuse/dependence with moderate overlap between the genetic factors associated with these outcomes. Additionally, there were strong associations between measures of lifetime stimulant use and analogous measures of cannabis use which, importantly, could be largely attributed to shared familial risk factors predisposing to both stimulant and cannabis use.