Cognitive Control in Opioid Dependence and Methadone Maintenance Treatment

• Published in: PloS one Vol. 9; no. 4; p. e94589
• Main Authors: Liao, Ding-Lieh, Huang, Cheng-Yi, Hu, Sien, Fang, Su-Chen, Wu, Chi-Shin, Chen, Wei-Ti, Lee, Tony Szu-Hsien, Chen, Pau-Chung, Li, Chiang-shan R.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.04.2014; Public Library of Science (PLoS)
• Subjects: Addictions; Addicts; Adult; Alcohol; Amphetamine - therapeutic use; Biology and Life Sciences; Cocaine; Cognition - drug effects; Cognition disorders; Cognitive ability; Comorbidity; Covariance; Demography; Drug abuse; Drug dependence; Education; Errors; Gender differences; Group effects; Health aspects; Health care; Heroin; Humans; Inhibition; Maintenance Chemotherapy; Male; Medical imaging; Medicine; Medicine and Health Sciences; Methadone; Methadone - pharmacology; Methadone - therapeutic use; Methadone hydrochloride; Middle Aged; Narcotics; Occupational safety; Opioid-Related Disorders - drug therapy; Opioid-Related Disorders - physiopathology; Opioid-Related Disorders - psychology; Opioids; Physical Sciences; Psychiatry; Public health; Reaction time; Reaction Time - drug effects; Reaction time task; Rehabilitation; Risk factors; Risk reduction; Social Sciences; Substance abuse treatment; Systematic review; Task Performance and Analysis; Variance analysis; Taiwan; United States > US; Connecticut
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0094589

Substance misuse is associated with cognitive dysfunction. We used a stop signal task to examine deficits in cognitive control in individuals with opioid dependence (OD). We examined how response inhibition and post-error slowing are compromised and whether methadone maintenance treatment (MMT), abstinence duration, and psychiatric comorbidity are related to these measures in individuals with OD. Two-hundred-and-sixty-four men with OD who were incarcerated at a detention center and abstinent for up to 2 months (n = 108) or at a correctional facility and abstinent for approximately 6 months (n = 156), 65 OD men under MMT at a psychiatric clinic, and 64 age and education matched healthy control (HC) participants were assessed. We computed the stop signal reaction time (SSRT) to index the capacity of response inhibition and post-error slowing (PES) to represent error-related behavioral adjustment, as in our previous work. We examined group effects with analyses of variance and covariance analyses, followed by planned comparisons. Specifically, we compared OD and HC participants to examine the effects of opioid dependence and MMT and compared OD sub-groups to examine the effects of abstinence duration and psychiatric comorbidity. The SSRT was significantly prolonged in OD but not MMT individuals, as compared to HC. The extent of post-error slowing diminished in OD and MMT, as compared to HC (trend; p = 0.061), and there was no difference between the OD and MMT groups. Individuals in longer abstinence were no less impaired in these measures. Furthermore, these results remained when psychiatric comorbidities including misuse of other substances were accounted for. Methadone treatment appears to be associated with relatively intact cognitive control in opioid dependent individuals. MMT may facilitate public health by augmenting cognitive control and thereby mitigating risky behaviors in heroin addicts.