Hylke K.E. Vervaeke

Ecstasy use and self-reported depression, impulsivity, and sensation seeking: a prospective cohort study

Although there are indications that ecstasy users have higher levels of depression, impulsivity, and sensation seeking, it is unknown whether these are consequences of ecstasy use or predisposing factors for starting ecstasy use. We prospectively assessed the predictive value of depression, impulsivity, and sensation seeking on future .rst time ecstasy use. We also assessed whether depression, impulsivity, and sensation seeking had changed after .rst ecstasy use. Depression, impulsivity, and sensation seeking were assessed using self-report questionnaires in 188 ecstasynaive volunteers with high probability for future ecstasy use. After a mean follow-up of 17 months, measurements were repeated in 59 incident ecstasy users (mean 6.0 tablets) and 61 matched persistent ecstasy-naive volunteers. Only experience seeking (subscale of the sensation seeking scale) predicted future ecstasy use (OR -- 1.05, 95% CI 1.00 to 1.10), but after adjustment for potential confounders this was not signi.cant anymore. At follow-up, signi.cant effects of ecstasy use on the general and the disinhibition subscale of the sensation seeking scale were observed (after adjustment for potential confounders: regression coef.cient B 0.51, 95% CI 0.20 to 0.83 and B -- 3.25, 95% CI 1.74 to 4.76, respectively). These data indicate that depression, impulsivity, and sensation seeking do not predict .rst time ecstasy use in a population of young adults with the intention to start using ecstasy and that low level ecstasy use does not seem to cause depression or impulsivity. However, low level ecstasy use may increase (certain aspects of) sensation seeking.

The role of peers in the initiation and continuation of ecstasy use

This study is a supplement to the Netherlands XTC Toxicity Study (NeXT), funded by grants from the Netherlands Organisation for Health Research and Development as part of its Addiction Programme. To better understand the processes of peer influence and peer selection, in a field study 106 Ecstasy users (67M/39F, average age 25.4 years) were interviewed face-to-face in Amsterdam in 2005. In the initiation of Ecstasy use, peer influence emerged as the dominating mechanism; peer selection was uncommon. In the continuation of Ecstasy use, peer influence and peer selection occurred reciprocally in a dynamic process, although peer influence made a greater relative contribution. Our study confirms that peer influence is a multidimensional process: influence was quite often reciprocal (with respondents both exerting and undergoing influence) and it could have both restraining and encouraging effects on ecstasy use. The studys limitations are noted.

Predicting ecstasy use among young people at risk: a prospective study of initially ecstasy-naive subjects.

Our aim is to identify predictors of first-time ecstasy use in a prospective study among young people at risk. As part of the multidisciplinary Netherlands XTC Toxicity Study (NeXT), we monitored 188 subjects aged ≥ 18 who were ecstasy-naive at baseline but seemed likely to start taking ecstasy in the near future. After an 11- to 26-month follow-up period, 160 respondents remained (85.1%; mean age 21.0 years, 58.1% females): 65 who took ecstasy at least once (ecstasy users) and 95 non-users. At baseline and four times during follow-up, respondents completed self-report questionnaires. Cox regression analysis was used to examine the effects of baseline respondent characteristics on incident ecstasy use. Development of peer group ecstasy use was analyzed by logistic regression. Intention to use ecstasy, low education, and current weekly cannabis use independently increased the hazard rate for first ecstasy use. Although ecstasy use among peers at baseline was not a predictor, the proportion of ecstasy users with ecstasy-using peers increased markedly during the study. Our results suggest that targeted prevention activities should focus in particular on young people who have strong intentions to take ecstasy, especially if they are also regular smokers of cannabis.

Fear, Rationality and Opportunity: Reasons and Motives for Not Trying Ecstasy.

Aim: To gain more insight into the reasons and motives why people do not start taking ecstasy. Method: As part of the NeXT Study, we prospectively monitored 188 subjects who were ecstasy-naive at baseline but seemed likely to take ecstasy (MDMA) of their own accord during the course of the study. After an 11- to 26-month follow-up period, 160 respondents remained (85.1%). Among these, 65 participants started taking ecstasy (novel ecstasy users, NEUs) and 95 did not (persistent non-users, PNUs). Several times during their participation, subjects completed lists of reasons and motives for not taking ecstasy. Findings: Principal components analysis identified three main factors associated with non-use: rationality (factor score 0.491), lack of opportunity (0.229) and fear of the effects of ecstasy (0.211). At baseline, PNUs scored higher than NEUs on all three factors. For the NEUs, no significant changes occurred over the course of the study in all three factor curves. Slight shifts were seen for PNUs—the fear of effects diminished and lack of opportunity grew; scores on rationality remained constant. Conclusions: NEUs and PNUs were distinguished most clearly by their factor scores on rationality. Some valuable insights for prevention are discussed.