Ecstasy (MDMA): are the psychological problems associated with its use reversed by prolonged abstinence?

RATIONALE: Chronic, regular recreational use of ecstasy (MDMA) is associated with psychopathology, elevated behavioural impulsivity and persistent impairment of memory performance.
OBJECTIVE: The aim of the present study was to investigate which of these sequelae persist after at least 6 months of abstinence from ecstasy.
METHODS: Four groups of participants were compared: 18 current regular recreational ecstasy users, 15 ex-regular ecstasy users who had abstained from using the drug for an average of 2 years, 16 polydrug users who had never taken ecstasy and 15 drug-naive controls.
RESULTS: There were no significant group differences in age, education level, or pre-morbid intelligence and, generally, the use of illicit drugs other than ecstasy was not significantly different among the three drug-using groups. Both current and ex-ecstasy users exhibited elevated psychopathology and behavioural impulsivity compared with polydrug users and drug-naive controls, but current ecstasy users exhibited a broader range of psychopathology than ex-users. Both groups of ecstasy users also exhibited impaired working memory and verbal recall performance compared with drug-naive controls, but only ex-users exhibited impaired verbal recall relative to polydrug users. Regression analysis indicated that psychopathology was primarily predicted by the extent of previous consumption of cannabis rather than ecstasy, whereas the majority of the cognitive deficits were only predicted by the extent of previous ecstasy use.
CONCLUSIONS: Selective impairments of neuropsychological performance associated with regular ecstasy use are not reversed by prolonged abstinence. This is consistent with evidence that ecstasy has potent and selective neurotoxic effects on brain serotonergic systems in humans.