A Comparison of Cognitive Function in Patients under Maintenance Treatment with Heroin, Methadone, or Buprenorphine and Healthy Controls: An Open Pilot Study

Introduction: Cognitive impairment has been reported in drug-dependent patients under opioid maintenance treatment. Objectives: To compare cognitive functioning in healthy controls and in opioid-dependent patients treated with Buprenorphine, Heroin, or methadone maintenance. Methods: We used the standardized test battery ART-90 to study cognitive function in patients under long-term heroin treatment (n = 20), Bup (n = 22), or Met (n = 24) maintenance treatment and healthy controls (n = 25). Results: Patients receiving heroin performed significantly worse than healthy controls in most domains. Heroin patients performed worse than patients in the other two treatment groups in subtests measuring psychomotor performance under stress conditions and monotony. Conclusions and Scientific Significance: Although a number of limitations must be taken into account, this study provides some preliminary evidence that cognitive function may be more impaired in patients under heroin maintenance treatment than in patients receiving Bup or Met and in healthy controls.