Background-Opiate-dependent individuals are prone to dysphoria that may contribute to treatment failure. Methadone-maintenance therapy (MMT) may mitigate this vulnerability, but controversy surrounds its long-term use. Little is known about the neurobiology of mood dysregulation in individuals receiving or removed from MMT.Methods-Fifteen opiate-abstinent and 12 methadone-maintained, opiate-dependent subjects, who lacked other Axis I pathology, and 13 control subjects were compared on the Cornell Dysthymia Rating Scale (CDRS) and regional cerebral glucose metabolism (rCMRglc) using [ 18 F] fluorodeoxyglucose positron emission tomography.Results-CDRS scores showed no group differences. Opiate-abstinent subjects had lower rCMRglc than control subjects in the bilateral perigenual anterior cingulate cortex (ACC), left midcingulate cortex, left insula and right superior frontal cortex. Methadone-maintained subjects exhibited lower rCMRglc than control subjects in the left insula and thalamus. In opiate-abstinent subjects, rCMRglc in the left perigenual ACC and mid-cingulate cortex correlated positively with CDRS scores.Conclusions-In remitted heroin dependence, opiate-abstinence is associated with more widespread patterns of abnormal cortical activity than MMT. Aberrant mood processing in the left perigenual ACC and mid-cingulate cortex, seen in opiate-abstinent individuals, is absent in those receiving MMT, suggesting that methadone may improve mood regulation in this population.

Objective-Methadone Maintenance Therapy (MMT) and detoxification to abstinence are among the most common treatment options for opiate-dependent patients. This paper compares personality traits in detoxified former heroin users and those on MMT in order to assess their relevance to treatment selection.Methods-Twenty-six formerly heroin-dependent subjects receiving MMT (MM), 33 formerly heroin-dependent subjects withdrawn from MMT (MW), and 43 healthy controls were compared on the Millon Clinical Multiaxial Inventory-II (MCMI-II) and the Temperament and Character Inventory (TCI).Results-On the TCI, MM patients had higher Novelty Seeking and lower Self Directedness scores than controls. Both MM and MW subjects scored higher than controls on multiple MCMI-II scales. MW but not MM subjects scored higher than controls on 2 Cluster A scales and the Delusional Disorder scale.Conclusions-Schizophrenia-spectrum pathology in former opiate users may be greater than previously recognized and could potentially be relevant to treatment selection.