A longitudinal study of self-reported psychopathology in early ecstasy and amphetamine users.
It still remains unclear whether psychopathological abnormalities described in human 3,4-methylenedioxymethamphetamine users (MDMA users) and d-amphetamine users (AMPH users) existed before the beginning of regular use or if they develop with ongoing use. The present study was conducted in order to assess this relationship and to overcome previous methodological shortcomings. A longitudinal cohort study in 96 beginning MDMA and d-amphetamine users between 2006 and 2011 with a follow-up duration of 24 months. In order to explore the impact of MDMA and AMPH use on self-reported psychopathology (measured by the Symptom Checklist-90-Revised), mixed models for repeated measures were fitted. In order to examine the impact of previous psychopathology on subsequent use, partial correlation analyses and linear regression analyses were applied. Over the course of the 2-year follow-up period, 31 subjects used neither MDMA nor AMPH (non-users) 65 subjects used both MDMA and AMPH 37 subjects used between 1 and 14 tablets of MDMA and 28 subjects used 15 or more tablets of MDMA. Thirty-three subjects used between 1 and 14 g of AMPH, and 32 subjects used 15 g or more. No associations concerning MDMAAMPH use and development of self-reported psychopathology were found. However, there was a significant relationship between globally increased self-reported psychopathology-particularly psychoticism-at the beginning of the study and subsequent AMPH use. The data of the present study suggest that a certain psychopathological profile could form a risk factor for later use of amphetamines.