Ecstasy is a widely used psychoactive drug that users often take because they experience positive effects such as increased euphoria, sociability, elevated mood, and heightened sensations. Ecstasy use is not harmless and... [ view full abstract ]
Ecstasy is a widely used psychoactive drug that users often take because they experience positive effects such as increased euphoria, sociability, elevated mood, and heightened sensations. Ecstasy use is not harmless and several immediate and long term side effects have been identified. We examined the demographics of ecstasy users and determined the relationship of ecstasy use with use of other substances (legal and illegal). We also estimated the heritability of ecstasy use and the genetic association of ecstasy use with smoking, alcohol, and cannabis use.
The sample comprised >8,500 twins and siblings aged 18-45 years from twin families registered at the Netherlands Twin Registry. In 2013-2014 participants filled out a questionnaire including questions about ecstasy use. A subset of these individuals (N>4000) were also genome-widely genotyped. We used the classical twin design to partition the individual differences in liability to ecstasy use into genetic, shared environmental, and residual components. Moreover, we created polygenic risk scores for tobacco, alcohol, and cannabis use and determined to what extent these polygenic scores could predict ecstasy use.
Approximately 10% of the sample had used ecstasy during their lifetime, with a somewhat higher prevalence in males than females. On average, ecstasy users more often lived in urbanized areas and were higher educated than non-users. Ecstasy users were significantly more likely to have used other substances (legal or illegal) compared to non-users. Twin modelling indicated that individual differences in liability to lifetime ecstasy use are for 74% due to genetic differences between individuals, whereas shared environmental and residual factors explain a small proportion of its liability (5% and 21%, respectively). Polygenic risk scores for cannabis use (but not tobacco or alcohol use) significantly predicted lifetime ecstasy use in our sample. This indicates that there is overlap in the genetic vulnerability between use of cannabis and ecstasy.
