Association between platelet MAO activity and lifetime drug use in a longitudinal birth cohort study.

Rationale: Platelet monoamine oxidase (MAO) activity, a marker of central serotonergic capacity, has been associated with a variety of problem behaviours. However, studies on platelet MAO activity and addictive drugs have not consistently linked MAO activity with addiction or reported to predict illicit substance use initiation or frequency.

Objectives: Platelet MAO activity and illicit drug use was examined in a longitudinal birth cohort study.