Relationship between ecstasy use and depression: a study controlling for poly-drug use (2004)

RATIONALE: 3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy") causes serotonin neuron damage in laboratory animals. The serotonin system is known to be important in the regulation of mood. Previous research has shown that MDMA users score higher on self-report ratings of depression than controls. However, MDMA users commonly take other illicit substances and many studies do not fully control for polydrug use. OBJECTIVES: The aim of this study was to examine the relationship between MDMA use and affective disturbance, while fully controlling for polydrug use. METHODS: Participants were 30 current MDMA users, 30 poly-drug controls who had never used MDMA, 30 drug-naive controls with no history of illicit drug use and 20 ex-MDMA users. The current MDMA users and poly-drug controls were well matched on all indices of non-MDMA drug use. All participants were administered the Beck Depression Inventory (BDI) and the Affective Go/No-go task, which has been shown to be sensitive to depression. RESULTS: The current and ex-MDMA users scored significantly higher on the BDI than the drug-naive controls, but were not significantly different from the poly-drug controls. There were no differences between the groups in terms of affective bias scores on the Affective Go/No-go task. CONCLUSIONS: Increased scores on self-report depression scales in MDMA users are not entirely attributable to MDMA use. MDMA users do not show the same attentional bias towards negatively toned material as depressed patients. (Author' s abstract)