Lack of longitudinal changes in cognition in individuals with methamphetamine use disorder during the first 6 weeks after commencing treatment

Rebecca E. Fitzpatrick, Alex H. Robinson, Adam J. Rubenis, Dan I. Lubman, Antonio Verdejo-Garcia

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Background: Methamphetamine use disorder (MUD) associates with cognitive impulsivity deficits. However, few studies have examined longitudinal changes in cognition, and it remains unclear if deficits resolve during early recovery. Objectives: To compare: (1) cognitive function of individuals with MUD at treatment onset and six-weeks later with controls tested over the same period; (2) cognitive changes in MUD-individuals who remained abstinent versus relapsed. Method: We recruited 108 participants meeting DSM-IV-TR criteria for methamphetamine dependence (81 males) and 50 demographically matched controls (38 males); 77 methamphetamine- dependent participants (59 males) and 48 controls (36 males) were retained at follow-up. We administered response inhibition, delay discounting and uncertainty-based decision-making tests at both endpoints. Relapse was defined as methamphetamine concentrations >0.4 ng/mg at follow-up in hair toxicology. Results: We found a significant time-by-group interaction on uncertainty-based decision-making (effect size: η2 = .05), although post-hoc tests to disentangle this interaction yielded inconclusive results (p-range = .14–.40; BF10 -range = 0.43–1.67). There were no significant time-by-group interactions on response inhibition or delay discounting, with the former likely a null effect (η2 -interaction = .003 and.02; BFincl = 0.23 and 0.71). There were no significant differences in cognitive recovery between individuals who maintained abstinence (n = 12) versus relapsed (n = 65) (η2 -range = .003-.04), although evidence was inconclusive toward whether findings reflected true null effects (BFincl -range = 0.33–0.75). Conclusion: We did not find evidence that MUD-related cognitive impulsivity deficits improve beyond practice effects over 6 weeks. Findings do not support previous, albeit conflicting, evidence of early recovery of cognitive deficits in MUD.

Original languageEnglish
Number of pages10
JournalAmerican Journal of Drug and Alcohol Abuse
DOIs
Publication statusAccepted/In press - 2021

Keywords

  • cognitive recovery
  • cognitive tests
  • impulsivity
  • Methamphetamine use disorder

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