Purpose: Psychological, psychiatric: to investigate the relationship between the psychological profile of ecstasy users and their drug use patterns, to discover whether ecstasy use is associated with differences in personality or in number and type of psychiatric complaints.

Design: Non-experimental (retrospective) 3-group between subjects (across group) design, with drug use (ecstasy user, cannabis user or non-drug user) serving as a between subjects factor, and with participants in all groups completing measures of personality and of psychiatric symptoms.

Subjects: 28 ecstasy users, 28 cannabis users and 28 non-users in the Aachen (Germany) area, with subjects recruited directly by students participating in the dance scene or through word of mouth. Matching - On gender, age and education. Ecstasy users and cannabis users matched on extent of cannabis use. (Participants in this study are identical to participants appearing in Gouzoulis-Mayfrank et al. 2000, a study comparing cognitive performance across groups).

Criteria for Inclusion - Ecstasy Users - Regular ecstasy use for 6 months or longer, minimum frequency of use; twice a month or 25 instances in 2 years. No regular use of other legal or illegal drugs except cannabis, with regular use defined as at least once a month in past 6 months, and no heavy use of alcohol, defined as severe drunkenness 2 or more times a month. Cannabis Users - No use of ecstasy, all other criteria above concerning drug and alcohol use, and cannabis use matched with that of ecstasy users. Non-Users - No past or current use of cannabis, ecstasy or any other illicit substance, and lack of heavy alcohol use. All Groups - Absence of any major medical or psychiatric disorder (excepting substance abuse for drug user groups), ascertained through medical and psychiatric interview, and abstinence from ecstasy or cannabis for at least 7 days before study day, with compliance verified through urinary analysis on the study day.

Drug Use Parameters - Ecstasy users took ecstasy, on average, 93.4+/- 119.9 times over a lifetime (20-500), using an average dose of 1.4 +/- .9 tablets per use (.5 - 3.5 tablets per occasion). Average frequency of use was 2.4 +/- 1.6 times per month (.75 - 8 times), and average duration of use in months was 27 +/- 18 months (6-60). Self-reported length of drug-free period before study day, in days was 41 +/- 71 days (7-356 days). 26 / 28 were regular ecstasy users and 2 / 28 were sporadic users. The average age when ecstasy was first used = 19.4 +/- 3.3 years (14-27 years). Cannabis use - 22 ecstasy users were regular cannabis users, 1 used cannabis sporadically and 5 did not use cannabis. In matched cannabis user group, 23 were regular cannabis users, 2 were sporadic cannabis users and 3 did not use cannabis. Cannabis was used on 20.7 +/- 11.5) days a month by ecstasy users and 20.9 +/- 10.2 days per month by cannabis users. Duration of cannabis use extends for 66.6 +/- 37 months for ecstasy users and for 35.1 +/-24 months for cannabis users. Ecstasy users had last used cannabis 4.3 +/- 5.3 days before the study day and cannabis users last used cannabis 4 +/- 15.5 days before the study day. 17 ecstasy users and 20 cannabis users tested positive for presence of THC in urine on study day, and 11 ecstasy users and 8 cannabis users tested negative for THC in urinary analysis. Average age of first cannabis use for ecstasy users = 16.6 +/- 2.9 years, and the average age of first cannabis use for cannabis users = 17.1 +/- 2.4 years.

Group Demographics and Matched Variables - Ecstasy users matched with both cannabis user and non-user controls on gender, age and education level. Gender, as M / F ratio - ecstasy users, 16/12: cannabis users, 15/13: non-users, 17 / 11. Age - Ecstasy users, 18-29, mean = 23.25, cannabis users, 18-31, mean = 22.9, non-users, 18-30, mean = 23.5. Education level - Little / no secondary school - 1 ecstasy user, 0 cannabis users, 0 non-users: "Basic" school-leaving exam - 2 ecstasy users, 2 cannabis users, 0 non-users: "intermediate" school-leaving exam - 8 ecstasy users, 5 cannabis users, 8 non-users: "highest" school-leaving exam - 16 ecstasy users, 20 cannabis users, 20 non-users: university degree - 1 ecstasy user, 1 cannabis user, 0 non-users. Average education, ecstasy users = 3.5 (approx. 11 years), cannabis users = 3.7 (approx. 12 years), non-users = 3.7 (approx. 12 years). Cannabis Use - Ecstasy users matched with cannabis using controls on cannabis use. Regular cannabis use - 22 ecstasy users, 23 cannabis users: sporadic cannabis use - 1 ecstasy user, 2 cannabis users: No cannabis use - 5 ecstasy users, 3 cannabis users. Duration of regular cannabis use significantly longer for ecstasy users than for cannabis users, and early age of onset for ecstasy use was significantly associated with early age of onset for cannabis use.

Measures: Personality - Personality dimensions were measured via Freiburg Personality Inventory-Revised, with subscales for satisfaction, social orientation, inhibition, excitability, aggressiveness, somatic complaints, health worry and extroversion), Impulsiveness and novelty seeking measured via Sensation Seeking Scale (SSS -V) and Barratt Impulsiveness Scale before evoked potential recordings performed. Aggressiveness, anger and hostility measured with the State-Trait Anger-Depression Inventory-Trait form and the Questionnaire for Aggressiveness Factors (FAF), a German-language version of the BDHI. Trait anxiety measured via the State Trait Anxiety-Trait form.

Psychiatric Symptoms - SCL-90 used to measure occurrence of psychiatric complaints, with both sub-scale scores and global index scores (severity, positive symptom distress and positive symptom total) calculated. The [Van Zerssen] Depression Scale (DS), a self-administered measure of depression as administered as a measure of depression.

Analyses: All measures of personality and psychiatric symptoms were analyzed via 1-way between-subjects ANOVA, with drug use (ecstasy user, cannabis user, non-drug using control) serving as the between-subjects factor, with p. set at 0.05. Post-hoc comparisons were made via Scheffe's test; because of its conservatism, the 0.1 level was used reported as well as the 0.05 level.

Drug Use Parameters and Psychometric Scores - Scores on all measures of personality and psychiatric symptoms were correlated with extent of ecstasy use and extent of cannabis use.

Analyses of Covariance - After initial analyses found relationships between age of onset and duration of cannabis use and psychometric measures, analyses of covariance (ANCOVAs) were performed with age of onset for cannabis use and duration of cannabis use as covariates.

Results - Significant Differences Found: Impulsivity - Ecstasy users scored significantly higher than non-drug users on non-planning impulsivity scale of BIS, and they scored marginally higher than cannabis users on non-planning impulsivity (ecstasy users > cannabis users > = non-drug controls. Ecstasy users scored higher than cannabis users on "experience seeking" on SSS. (Ecstasy users = non-drug > cannabis). Cannabis users scored higher than ecstasy users on "thrill and adventure seeking" than non-users (Cannabis = ecstasy users > controls). Ecstasy users had higher FPI somatic complaint scores than non-drug controls, but not cannabis users. (ecstasy users = cannabis users = > non-drug controls). Aggressiveness - Cannabis users had significantly higher scores for reactive aggression and significantly lower scores for aggressive inhibition than ecstasy users. Cannabis users also had lower aggression inhibition scores than non-drug controls. (Reactive aggression, Cannabis users = > ecstasy users = non-drug controls). Aggression inhibition. (Cannabis users > non-drug controls = > ecstasy users). Psychiatric Symptoms - Ecstasy users had significantly higher scores than non-drug controls on the following SCL-90 scales; phobic anxiety, obsession-compulsion, paranoid ideation, psychoticism. (ecstasy users = cannabis users, ecstasy users > non-drug users).

Drug Use Parameters and Psychometric Variables - Duration of regular ecstasy use, lifetime ecstasy use (total number of tablets taken) and frequency of ecstasy use were all (apparently positively) associated with measures of impulsiveness, experience seeking (BIS), aggression (not described), depression, anxiety, obsessive-compulsiveness and psychoticism. The duration of regular cannabis use and age of onset for cannabis use were also associated with these measures of personality and psychiatric symptoms. (The nature of the relationships is not given separately for reach variable, so it is assumed all are positively correlated with each drug-use variable).

Analyses of Covariance - After using age of onset of cannabis use and duration of cannabis use as covariates, cannabis users found to differ from ecstasy users and non-user controls on 3 psychometric scores, thrill-seeking, experience and aggression inhibition. Though direction not specified, earlier analysis would indicate that cannabis users had higher thrill-seeking scores than the other 2 groups and lower experience seeking and aggression inhibition scores.

Results - No Significant Differences: Impulsivity - There were no significant differences between all three groups on attentional impulsivity and motor impulsivity on BIS. Ecstasy users, cannabis users and controls did not have significantly different SSS Scores for boredom susceptibility or disinhibition. There were no significant differences between ecstasy users and non-drug controls on "experience seeking" SSS score. Members of all 3 groups attained similar scores on all FPI scales (satisfaction, social and achievement orientation, inhibition, excitability, health worries, and extroversion). Aggression - Ecstasy users did not significantly differ from non-drug controls on any FAF (German BDHI) scores, and they did not differ from cannabis users on spontaneous aggression, irritability, negativism or resentment scores. Cannabis users did not differ from non-users on all FAF scores except for aggression inhibition. The three groups did not differ on STAXI trait aggressiveness scores or on FPI aggressiveness scale scores. Psychiatric symptoms - All 3 groups did not attain significantly different scores on the following SCL-90 scales: somatization, interpersonal sensitivity, anxiety, hostility, or any of the SCL-90 global and positive symptom indices. Ecstasy users and cannabis users attained similar scores on SCL-90 measures of phobic anxiety, paranoid ideation and psychoticism. All three groups scored similarly on the DS (depression scale) and the STAI.

Drug Use Parameters and Psychometric Scores - No associations were found between any ecstasy use or cannabis use parameters for all STAXI, STAI, FPI scores, and for all other BIS (impulsivity), FAF (aggression), SSS and SCL-90 scores not found to be associated with duration of ecstasy or cannabis use, total lifetime ecstasy use, frequency of ecstasy use or age of onset for cannabis use.

Analysis of Covariance - Ecstasy users, cannabis users and non-drug users no longer differed on all other variables found to be significant when analyzed via ANOVA except for those scale scores listed above (SSS "experience" and "thrill" scores, FAF "aggression inhibition" score) after age of onset for cannabis user and duration of cannabis user were treated as covariates.

Overall Effects: Ecstasy users had higher unplanned impulsivity scores on the BIS and higher experience seeking scores on the SSS when compared with cannabis user and non-drug user controls matched for age and gender. However, none of the groups had significantly different scores on measures of aggression, anxiety, depression or psychiatric symptoms (such as interpersonal sensitivity). Cannabis users had lower aggression inhibition scores than either ecstasy users or controls (indicating a difficulty suppressing aggression) and greater reactive aggression scores than ecstasy users. None of the 3 groups differed on extroversion, excitability, social orientation, achievement orientation, satisfaction or health worries. SCL-90 somatization, phobic anxiety, paranoid ideation and psychoticism scores, and somatic complaint scores on the FPI were significantly higher in ecstasy users than in non-user controls, but they were not significantly higher than those of cannabis users. When a subsequent analysis of covariance treated age of onset of cannabis use and duration of cannabis use as covariates, differences between ecstasy users and non-drug users were no longer significant. However, cannabis users still had higher thrill-seeking scores than ecstasy users or non-drug users, and they had lower experience-seeking and aggression-inhibition scores.

Comments: The findings reported here are consonant with findings reported in a number of other papers (e.g. Morgan et al. 2002; Parrott et al. 2001b) that have failed to find a simple relationship between ecstasy use and psychiatric symptoms. Since recent drug use was verified via urinary analysis, not self-report alone, the results are less likely to be influenced by potential recent drug use. Unlike Gerra et al. (2001), no relationship was found between ecstasy use and increased aggression, even though self-reported time since last use was equal to or shorter than that reported by the sample studied by Gerra and colleagues. However, this study employed an instrument of self-reported aggression, whereas Gerra et al. relied on laboratory induced aggression. Along with findings reported elsewhere, study findings suggest changes in psychological function are not predictably produced by regular ecstasy use and cannot serve as an indicator of ecstasy-induced neurotoxicity. Rather, these and other study findings lend support to contentions that factors predisposing people to use drugs, or perhaps the effects of other drugs, and not ecstasy use per se, that are associated with greater impulsivity, higher number of psychiatric symptoms or greater aggression. In contrast, findings from a study using the same sample (Gouzoulis-Mayfrank et al. 2000) found that tests of cognitive function, especially verbal memory and executive function, did distinguish ecstasy users from cannabis users and non-drug users. All recent publications relating to psychological function are retrospective studies wherein selection is non-random (based on past behavior), and the limitations applicable to retrospective studies apply to this study as well.