Self-reported depressive symptomatology in community samples of polysubstance misusers who report Ecstasy use: a meta-analysis

National drugs information strategies convey the message that use of Ecstasy is associated with an increase in both the incidence and severity of major depressive disorder. However, very little primary research supports this. Unlike apparent deficits in higher cognitive functions, most published studies have found no difference in self-reported depressive symptomatology between Ecstasy users and controls. To investigate this further, we conducted a meta-analysis of studies investigating depressive symptomatology in recreational users of Ecstasy. According to selection criteria, we identified 25 relevant studies. A statistically significant effect size (ES) of 0.31 (95% confidence interval 0.17-0.37, p < 0.001) was calculated. Significance remained after examining the small number of studies that controlled for cannabis use (n = 9, p < 0.001) but, in general, drug histories were poorly reported. There was an association between ES and Lifetime Ecstasy exposure (p < 0.001), but not for other use parameters or abstention (p > 0.05). These data indicate that there is an association between Ecstasy use and depressive symptomatology, but this is small and unlikely to be clinically relevant. In addition, the self-report scales used may be heavily confounded by the somatic effects of substance misuse. Public health strategies derived from psychopharmacological investigations should acknowledge the potential negative effects of substance misuse but qualify the difficulties in interpreting research studies.