Investigating Cognitive Functions in Methadone Users in Comparison with Methadone and Methamphetamine Users and Control Group

Document Type : Original Article

Authors

1 Neuroscience Research Center, Institute of Neuropharmacology AND Department of Psychiatry, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran

2 Neurology Research Center AND Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran

3 Department of Psychiatry, Afzalipour School of Medicine AND Neurology Research Center, Kerman University of Medical Sciences, Kerman, Iran

4 Neurology Research Center, Kerman University of Medical Sciences, Kerman, Iran

10.22122/ahj.2022.91879

Abstract

Background: Cognitive impairment in drug users is a marker for predicting recurrence and poorer adherence 
to treatment. The purpose of this study was to compare the cognitive function in three groups of methadone 
users methadone maintenance treatment (MMT), compared to methadone and methamphetamine (MAMP) 
users (MMT + MAMP) and healthy people (control group).

Methods: Three groups of 90 people including 30 users of MMT, 30 users of MMT + MAMP, and 30 healthy 
persons participated in this cross-sectional and purposeful study. The study was performed on outpatients of 
MMT Clinic of Psychiatric Hospital in Kerman, Iran. The demographic and related data questionnaire was 
filled out. In addition, Persian version of the Brief Assessment of Cognition in Schizophrenia (BACS) was 
used to assess cognitive function.

Findings: The mean of total number of scores and all BACS subscales were significantly better in control 
group than the other two groups of patients. Moreover, not only the mean of total number of BACS was 
significantly different between two substance abuser groups, but also there was a significant difference 
between them on verbal memory, digit sequencing, and token motor test, with MMT + MAMP group 
performing worse than MMT group.

Conclusion: Concomitant use of opioids and stimulant substance such as MAMP results in cumulative toxic 
effect of them on brain and cognitive functions.

Keywords