Effects of Atomoxetine for Cognitive Function in Methamphetamine-dependent Patients: A Randomized Controlled Trial

Abstract

Background: A substantial body of evidence indicates that methamphetamine abuse can lead to persistent and severe cognitive dysfunction. Preclinical studies and early pilot clinical investigations suggested that atomoxetine, a cognitive enhancer, may improve cognitive dysfunction. The present study evaluated whether atomoxetine would affect cognitive dysfunction in methamphetamine-dependent patients. Methods: Participants with methamphetamine dependence (N=86) under Methadone Maintenance Therapy (MMT) were enrolled in a double-blind, placebo-controlled, randomized clinical trial. This investigation was performed on 86 subjects to consume either 40 mg/day atomoxetine (n=45) or placebo (n=41) for 8 weeks. Between January 2016 and June 2017, volunteers were selected from methamphetamine abusers in MMT centers in Kashan City, Iran. They completed the Cognitive Abilities Questionnaire at the first and each monthly visit to assess the cognitive functions. The collected data were analyzed using the Independent Samples t-test, Mann Whitney U test, and Chi-square in SPSS software. Results: This study revealed that atomoxetine treatment improved some cognitive dysfunctions in methamphetamine users, including memory, inhibitory control, selective attention, decisionmaking, planning, sustained attention, and cognitive flexibility in methamphetamine users (P<0.05); however, social cognition improvement was less than others (P=0.107). There were only mild adverse effects in the placebo and atomoxetine groups. Conclusion: The obtained findings indicated the efficacy of atomoxetine for improving cognitive dysfunction in methamphetamine users and suggest the potential effectiveness of atomoxetine for treating them.