Neuropsychological functioning in patients under maintenance treatment with methadone or buprenorphine, opioid users and healthy individuals

Background and Aim: Methadone and buprenorphine are widely used for the treatment of opioid dependence. It has been discussed whether buprenorphine treatment may cause less cognitive impairment in comparison with methadone. Methods: One hundred twenty matched for age, gender and education were categorized into four subgroups: MMP (n=۳۰), BMP (n=۳۰), opioid users (n=۳۰) and healthy subjects (n=۳۰). The Symptom Checklist-۹۰ (SCL-۹۰) used to measure subjective psychopathology. Neuropsychological tests were administered to measure executive function, selective attention and learning/memory using Stroop test, Wisconsin Card Sorting test (WCST) and Wechsler working memory test (WWMT). Results The aim of present study was to evaluate cognitive performance in methadone-maintenance patients (MMP) and buprenorphine-maintenance patients (BMP) and compare to opioid users and healthy control subjects. Conclusion: Opioid users and MMP showed sever psychological distress in all and BMP in some symptoms. SCL-۹۰ global score of opioid users, MMP and BMP were ۱۵۲, ۹۸ and ۹۲ respectively which was significant difference with control group score (۵۸). Opioid users showed a significant impairment in all cognitive domains. Control group achieved better results than opioid users, MMP and BMP groups in most cognitive domains, indicating cognitive impairment in the patients under substitution treatment. BMP group performed better than MMP in Stroop and WCST tests. Scores on WWMT were higher in MMP compare to BMP groups however the difference was not statistically significant. The results indicated sever psychological distress and cognitive impairment in opioid users. MMP and BMP showed improvement in psychological distress and cognition in comparison with opioid users. In addition, treatment with buprenorphine may result in less impairment of cognitive functions compared to treatment with methadone.

کلیدواژه ها:

Opioid ، Methadone ، Buprenorphine ، Cognitive functions ، Psychological distress