Comparison of cognitive functioning in abstinent opiate-dependent individuals, methadone-maintenance patients and healthy controls: study protocol and update of the existing literature

Abstract

Aims: Cognitive dysfunction plays an important role in the treatment of opioid dependence but the extent of this role and the question of whether the cognitive dysfunction is primary or secondary are matters of controversy. Few studies have been conducted in this area, particularly in abstinent opioid users. This article will give a comprehensive update of the existing literature on this issue and will also describe the protocol of a study on cognitive function in opioid dependence. Methods: The study will compare abstinent opiate-dependent patients, opiate-dependent individuals on stable maintenance treatment with no substance use and matched healthy controls. Results: We are expecting the study to provide information about the severity or possible reversal of cognitive impairment in formerly opiate-dependent patients and opiate-dependent patients on stable maintenance treatment. Conclusion: The study will answer the question of whether opioid dependence can cause impairment in cognitive and executive functions.