Alterations in Volume and Intrinsic Resting-State Functional Connectivity Detected at Brain MRI in Individuals with Opioid Use Disorder

Background Structural and functional MRI studies have revealed brain alterations associated with opioid use disorder (OUD). However, previous research has been limited by small sample sizes, few female participants, and single-modality analyses. Purpose To identify structural and functional brain alterations in individuals with OUD using whole-brain data-driven methods to analyze T1-weighted MRI and resting-state functional MRI (rsfMRI). Materials and Methods This secondary analysis of the Collaboration Linking Opioid Use Disorder and Sleep study compared participants with OUD (data collection February 2021 to February 2023) receiving methadone treatment with healthy control participants (data collection February 2018 to May 2023). T1-weighted MRI and rsfMRI were analyzed using tensor-based morphometry and intrinsic connectivity distribution, respectively. Primary outcome measures included regional brain volumes and functional connectivity. Voxel-wise linear regression was used to assess group differences, with family-wise error correction. Pearson partial correlations were used to examine structure-function relationships. Results Compared with healthy control participants (