title: Impulsivity and attentional bias as predictors of modafinil treatment outcome for retention and drug use in crack-cocaine dependent patients: Results of a randomised controlled trial.
abstract: High impulsivity and attentional bias are common in cocaine-dependent patients and predict poor treatment outcomes. The pharmacological agent modafinil is studied for its cognitive-enhancing capacities and may therefore improve clinical outcomes in crack-cocaine dependent patients. In this study, we investigated first whether pre-treatment impulsivity and attentional bias predict treatment outcome; next whether the drug modafinil given as an add-on treatment to cognitive behavioural therapy (CBT) improves impulsivity and attentional bias; and last, whether changes in impulsivity and attentional bias are related to improvements in treatment outcome.
  
  
  
  Crack-cocaine dependent outpatients (n = 65) were randomised to 12 weeks CBT plus modafinil (400 mg/day) or only CBT. Self-reported impulsivity was assessed at baseline using the Barratt Impulsiveness Scale. At baseline and Week 12, we assessed inhibitory control as a behavioural measure of impulsivity, in terms of cognitive interference (Stroop task) and response inhibition ('stop-signal task'), and attentional bias with the addiction Stroop task. Clinical outcomes were CBT-retention and crack-cocaine use.
  
  
  
  At baseline, self-reported impulsivity predicted better CBT-retention; low self-reported and behavioural impulsivity and attentional bias predicted less crack-cocaine use. Changes in cognitive performance were not modafinil-related, but most likely due to low adherence. Improvements in impulsivity or attentional bias were not associated with CBT-retention nor changes in crack-cocaine use.
  
  
  
  Baseline impulsivity and attentional bias predicted clinical outcomes in crack-cocaine dependent patients. There were no firm indications that modafinil reduced impulsivity nor attentional bias in this population. Future studies involving cognitive-enhancing medications should include strategies to optimise adherence, to be better able to evaluate their potential.
authors.affiliation: Parnassia Addiction Research Centre (PARC), Brijder Addiction Treatment, The Hague, the Netherlands mascha.nuijten@brijder.nl.
authors.forename: Mascha
authors.initials: M
authors.lastname: Nuijten
authors.affiliation: Parnassia Addiction Research Centre (PARC), Brijder Addiction Treatment, The Hague, the Netherlands.
authors.forename: Peter
authors.initials: P
authors.lastname: Blanken
authors.affiliation: Department of Psychiatry, Academic Medical Centre, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Wim
authors.initials: W
authors.lastname: Van den Brink
authors.affiliation: Department of Psychiatry, Academic Medical Centre, University of Amsterdam, Amsterdam, the Netherlands Arkin Mental Health Care, Amsterdam, the Netherlands.
authors.forename: Anna E
authors.initials: AE
authors.lastname: Goudriaan
authors.affiliation: Parnassia Addiction Research Centre (PARC), Brijder Addiction Treatment, The Hague, the Netherlands Department of Child and Adolescent Psychiatry, Leiden University Medical Centre, Leiden University, Leiden, the Netherlands.
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Hendriks
mesh_terms: D001288:Attention / Q000187:drug effects*; D000070379:Attentional Bias / Q000187:drug effects*; D016739:Behavior, Addictive / Q000188:drug therapy; D001559:Benzhydryl Compounds / Q000627:therapeutic use*; D019970:Cocaine-Related Disorders / Q000188:drug therapy*; D015928:Cognitive Behavioral Therapy / Q000379:methods; D016578:Crack Cocaine / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D000077408:Modafinil; D018697:Nootropic Agents / Q000627:therapeutic use; D057190:Stroop Test; D016896:Treatment Outcome
chemical_list: D001559:Benzhydryl Compounds; D016578:Crack Cocaine; D018697:Nootropic Agents; D000077408:Modafinil
keywords: Adherence; attentional bias; cocaine dependence; cognition; cognitive behavioural therapy; crack cocaine; drug use; impulsivity; modafinil; randomised controlled trial