Structural brain characteristics of anabolic–androgenic steroid dependence in men

AIM: To identify differences in brain morphology between dependent and non‐dependent male anabolic–androgenic steroid (AAS) users. DESIGN: This study used cross‐sectional data from a longitudinal study on male weightlifters. PARTICIPANTS: Oslo University Hospital, Norway. SETTING: Eighty‐one AAS users were divided into two groups; AAS‐dependent (n = 43) and AAS‐non‐dependent (n = 38). MEASUREMENTS: Neuroanatomical volumes and cerebral cortical thickness were estimated based on magnetic resonance imaging (MRI) using FreeSurfer. Background and health information were obtained using a semi‐structured interview. AAS‐dependence was evaluated in a standardized clinical interview using a version of the Structured Clinical Interview for DSM‐IV, adapted to apply to AAS‐dependence. FINDINGS: Compared with non‐dependent users, dependent users had significantly thinner cortex in three clusters of the right hemisphere and in five clusters of the left hemisphere, including frontal, temporal, parietal and occipital regions. Profound differences were seen in frontal regions (left pars orbitalis, cluster‐wise P < 0.001, right superior frontal, cluster‐wise P < 0.001), as has been observed in other dependencies. Group differences were also seen when excluding participants with previous or current non‐AAS drug abuse (left pre‐central, cluster‐wise P < 0.001, left pars orbitalis, cluster‐wise P = 0.010). CONCLUSION: Male dependent anabolic–androgenic steroid users appear to have thinner cortex in widespread regions, specifically in pre‐frontal areas involved in inhibitory control and emotional regulation, compared with non‐dependent anabolic–androgenic steroid users.