title: Cognitive impairment in cocaine users is drug-induced but partially reversible: evidence from a longitudinal study.
abstract: Cocaine users consistently display cognitive impairments. However, it is still unknown whether these impairments are cocaine-induced and if they are reversible. Therefore, we examined the relation between changing intensity of cocaine use and the development of cognitive functioning within 1 year. The present data were collected as part of the longitudinal Zurich Cocaine Cognition Study (ZuCo(2)St). Forty-eight psychostimulant-naive controls and 57 cocaine users (19 with increased, 19 with decreased, and 19 with unchanged cocaine use) were eligible for analysis. At baseline and after a 1-year follow-up, cognitive performance was measured by a global cognitive index and four neuropsychological domains (attention, working memory, declarative memory, and executive functions), calculated from 13 parameters of a broad neuropsychological test battery. Intensity of cocaine use was objectively determined by quantitative 6-month hair toxicology at both test sessions. Substantially increased cocaine use within 1 year (mean +297%) was associated with reduced cognitive performance primarily in working memory. By contrast, decreased cocaine use (-72%) was linked to small cognitive improvements in all four domains. Importantly, users who ceased taking cocaine seemed to recover completely, attaining a cognitive performance level similar to that of the control group. However, recovery of working memory was correlated with age of onset of cocaine use-early-onset users showed hampered recovery. These longitudinal data suggest that cognitive impairment might be partially cocaine-induced but also reversible within 1 year, at least after moderate exposure. The reversibility indicates that neuroplastic adaptations underlie cognitive changes in cocaine users, which are potentially modifiable in psychotherapeutical or pharmacological interventions.
authors.affiliation: Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Vonmoos
authors.affiliation: Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: Lea M
authors.initials: LM
authors.lastname: Hulka
authors.affiliation: Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: Katrin H
authors.initials: KH
authors.lastname: Preller
authors.affiliation: Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: Franziska
authors.initials: F
authors.lastname: Minder
authors.affiliation: Center of Forensic Hairanalytics, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland.
authors.forename: Markus R
authors.initials: MR
authors.lastname: Baumgartner
authors.affiliation: Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: Boris B
authors.identifier: 0000000179332865
authors.initials: BB
authors.lastname: Quednow
mesh_terms: D000328:Adult; D017668:Age of Onset; D000697:Central Nervous System Stimulants / Q000008:administration & dosage / Q000009:adverse effects / Q000032:analysis; D003042:Cocaine / Q000008:administration & dosage / Q000009:adverse effects / Q000032:analysis; D019970:Cocaine-Related Disorders / Q000150:complications* / Q000503:physiopathology / Q000523:psychology*; D003071:Cognition / Q000187:drug effects / Q000502:physiology; D003072:Cognition Disorders / Q000139:chemically induced / Q000209:etiology* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006197:Hair / Q000737:chemistry; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects / Q000502:physiology; D009483:Neuropsychological Tests; D020127:Recovery of Function; D012720:Severity of Illness Index
chemical_list: D000697:Central Nervous System Stimulants; D003042:Cocaine