Neuropsychological function in ecstasy users: a study controlling for polydrug use.
BACKGROUND
A number of studies have compared ecstasy users to control groups on various measures of neuropsychological function in order to determine whether ecstasy use results in lasting cognitive deficits. However, few of those studies controlled adequately for non-ecstasy illicit drug use.


OBJECTIVE
The aim of this study was to investigate neuropsychological function in chronic ecstasy users while controlling for polydrug use.


METHODS
Neuropsychological function was assessed in four groups-30 current 3,4-methylenedioxymethamphetamine (MDMA) users with a little history of illicit drug use other than ecstasy and cannabis, 30 polydrug controls, 30 drug-naïve controls and 20 ex-MDMA users-using a battery of well-validated, computerized neuropsychological tests. The battery focused on memory, executive function, impulsivity and risk-taking.


RESULTS
Few differences were apparent between the groups, and on no measure were the current MDMA users impaired significantly relative to the polydrug controls. However, within the current MDMA users, questionnaire-measured impulsivity correlated with performance on a number of tests-a relationship that was not apparent in the controls.


CONCLUSIONS
These data highlight the complexity in understanding the current ecstasy literature and suggest that some individuals may be particularly vulnerable to cognitive impairment following chronic use. Although no differences were identified between the current MDMA users and the controls, trait impulsiveness was significantly correlated with impairment on a number of neuropsychological outcome measures in the MDMA users, but not in the controls. These data suggest that impulsive individuals may be those most at risk for the development of cognitive impairment following chronic ecstasy use.
Roiser
Jonathan P
JP
Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Box 189, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 2QQ, UK.
Rogers
Robert D
RD
Sahakian
Barbara J
BJ
D019969:Amphetamine-Related Disorders / Q000209:etiology* / Q000523:psychology; D003071:Cognition / Q000187:drug effects*; D003072:Cognition Disorders / Q000139:chemically induced* / Q000523:psychology; D003430:Cross-Sectional Studies; D003657:Decision Making / Q000187:drug effects; D006213:Hallucinogens / Q000009:adverse effects*; D006801:Humans; D007175:Impulsive Behavior / Q000139:chemically induced; D008568:Memory / Q000187:drug effects; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000009:adverse effects*; D012107:Research Design; D012309:Risk-Taking
D006213:Hallucinogens; D018817:N-Methyl-3,4-methylenedioxyamphetamine