title: Increased self-reported impulsivity in methamphetamine users maintaining drug abstinence.
abstract: Impulsivity has been proposed as an important factor in the initiation and maintenance of addiction. Indirect evidence suggests that some methamphetamine users report less impulsivity when they are using methamphetamine compared to when abstaining from drug use, but this hypothesis has not been directly tested.
  
  
  
  In this study, self-reports of impulsivity were obtained from 32 methamphetamine-dependent (DSM-IV) research participants and 41 healthy control subjects, using the Barratt Impulsiveness Scale-11. The methamphetamine users were assessed during an active period of methamphetamine use, as determined through urinalysis, and again after approximately 1 week of confirmed abstinence. Control subjects likewise completed two assessments. A subset of participants also completed serial assessments of the Beck Depression Inventory (Methamphetamine Group, N = 17, Control Group, N = 38) and the Methamphetamine Withdrawal Questionnaire (Methamphetamine Group, N = 12).
  
  
  
  There was a significant interaction of group with time on impulsivity (p = 0.044), reflecting a significant increase from the first to the second assessment in the methamphetamine users (p = 0.013), but no change among healthy control subjects. In contrast, depressive and withdrawal symptoms significantly decreased between the first and second assessments in the methamphetamine users (ps ≤0.01). Change in impulsivity in methamphetamine users was not significantly correlated with change in withdrawal or depression (ps >0.05).
  
  
  
  These findings suggest that methamphetamine users report more impulsivity when abstaining from drug use, an effect that is not significantly related to methamphetamine withdrawal. Attenuation of impulsivity may reinforce continued methamphetamine use in these individuals.
authors.affiliation: a Department of Clinical Psychology, Fuller Graduate School of Psychology, Fuller Theological Seminary , Pasadena , CA , USA.
authors.forename: Hannah W
authors.initials: HW
authors.lastname: Jones
authors.affiliation: b Department of Psychiatry and Biobehavioral Sciences , UCLA Semel Institute for Neuroscience , Los Angeles , CA , USA.|d Brain Research Institute, David Geffen School of Medicine , Los Angeles , CA , USA.
authors.forename: Andy C
authors.initials: AC
authors.lastname: Dean
authors.affiliation: b Department of Psychiatry and Biobehavioral Sciences , UCLA Semel Institute for Neuroscience , Los Angeles , CA , USA.
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Price
authors.affiliation: b Department of Psychiatry and Biobehavioral Sciences , UCLA Semel Institute for Neuroscience , Los Angeles , CA , USA.|c Department of Molecular and Medical Pharmacology , UCLA Semel Institute for Neuroscience , Los Angeles , CA , USA.|d Brain Research Institute, David Geffen School of Medicine , Los Angeles , CA , USA.
authors.forename: Edythe D
authors.initials: ED
authors.lastname: London
mesh_terms: D000328:Adult; D019969:Amphetamine-Related Disorders / Q000523:psychology*; D016022:Case-Control Studies; D003863:Depression / Q000523:psychology*; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000187:drug effects*; D008297:Male; D008694:Methamphetamine / Q000009:adverse effects*; D057566:Self Report; D013375:Substance Withdrawal Syndrome / Q000523:psychology*; D055815:Young Adult
chemical_list: D008694:Methamphetamine
keywords: Drug abuse; abstinence; impulsivity; methamphetamine; self-medication; stimulant; withdrawal