Brain cortical thickness in male adolescents with serious substance use and conduct problems

Abstract

Background: Adolescents with substance use disorder (SUD) and conduct problems exhibit high levels of impulsivity and poor self-control. Limited work to date tests for brain cortical thickness differences in these youths. Objectives: To investigate differences in cortical thickness between adolescents with substance use and conduct problems and controls. Methods: We recruited 25 male adolescents with SUD, and 19 male adolescent controls, and completed structural 3T magnetic resonance brain imaging. Using the surface-based morphometry software FreeSurfer, we completed region-of-interest (ROI) analyses for group cortical thickness differences in left, and separately right, inferior frontal gyrus (IFG), orbitofrontal cortex (OFC) and insula. Using FreeSurfer, we completed whole-cerebrum analyses of group differences in cortical thickness. Results: Versus controls, the SUD group showed no cortical thickness differences in ROI analyses. Controlling for age and IQ, no regions with cortical thickness differences were found using whole-cerebrum analyses (though secondary analyses co-varying IQ and whole-cerebrum cortical thickness yielded a between-group cortical thickness difference in the left posterior cingulate/precuneus). Secondary findings showed that the SUD group, relative to controls, demonstrated significantly less right > left asymmetry in IFG, had weaker insular-to-whole-cerebrum cortical thickness correlations, and showed a positive association between conduct disorder symptom count and cortical thickness in a superior temporal gyrus cluster. Conclusion: Functional group differences may reflect a more nuanced cortical morphometric difference than ROI cortical thickness. Further investigation of morphometric differences is needed. If replicable findings can be established, they may aid in developing improved diagnostic or more targeted treatment approaches.

• Adolescents
• cortical thickness
• substance use

Funding

This work was supported by grants from the National Institute on Drug Abuse (Grants DA 009842, 011015, 027748) and the Kane Family Foundation (kanefamilyfoundation.org). Dr Sakai's effort and his labs work are also supported by DA031761 and the Hewit Family Foundation. Serhiy Chumachenko's effort was supported by DA033219.

Declaration of interest

Drs. Sakai and Tanabe both received reimbursement in 2012 for completing a policy review for the WellPoint Office of Medical Policy & Technology Assessment (OMPTA), WellPoint, Inc., Thousand Oaks, CA, USA. Dr. Sakai serves on the board of the ARTS Foundation. Dr. Crowley received travel support from the American Psychiatric Association to participate in revising the Diagnostic and Statistical Manual of Mental Disorders. He previously received travel support from the National Institute on Drug Abuse for serving on its National Advisory Council. The other authors report no biomedical financial interests or potential conflicts of interest. The authors alone are responsible for the content and writing of this paper.