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Date: Thu, 22 Jun 2000 From: rick@maps.org Subject: Re: MDMA effects To All: Dave [Nichols] sent out a message yesterday mentioning an article that supposedly is another bit of evidence about the harmfulness of the recreational use of MDMA:
First, one comment from me. I just spoke to Dr. Carl Salzman at Harvard Medical School. He is an esteemed psychiatrist who among other things conducted psilocybin research with Walter Pahnke back in the 1960s. He confirmed my assumption that the SCL-90, which was used in Parrott's study, contains a scale for depression. Since MDMA is supposed to lead to lower serotonin levels and depression, the absence of significantly lower depression scores in the MDMA groups is noteworthy. Harry has much more important comments to make about the study.
The Parrott study is immensely frustrating with regards to what data is given about the subjects who took part. In general it is quite cautious in tone but the interpretation of the data lapses back into the usual assumptions. Briefly,here's what I noticed, I'm sorry it's not referenced but I'm away from the office for a week (Luckily I had this paper with me) 1. Firstly, there are several references to an 'in-press' edition of Neuropsychobiology which suggests to me that a whole edition of the journal may be devoted to this field and this particular point of view. McCann and Ricaurte have a couple of papers in there, perhaps it is a follow up to the Novartis conference held in London a couple of years ago? 2. The whole study seems to be a third year undergraduate project padded out into a paper. Subjects were obtained from a small town in Ireland and were friends and colleagues of one of the investigators, hence the population seems to be highly selected and there are no guarantees that they weren't chosen for some specific reason. How representative of the general drug taking population these subjects are is unknown; they all come from a small town in a rural part of the country which as far as I'm aware is not well known for its clubs and youth scene. 3. There is a real lack of subject demographics. We are told their mean age and gender but nothing else. No screening tools were used to assess current, clinically-relevant psychiatric health and no mention is made as to whether they had any pre-existing conditions (or indeed whether this was part of the exclusion criteria). This leads subject selection open to all the criticisms leveled at previous works.
4. Additional drug use was assessed by simply asking the subjects to indicate
as to whether they had used a drug before. These substances ranged from
Alcohol through to Opiates and results were shown as % of group. Tellingly,
there is no mention of prescription, psychiatric medications so we must
assume that either they weren't asked or they had never used them (I suspect
the former considering the lack of screening information). Ecstasy users
(Heavy users defined as >20 occasions, Light<20, never = 0 occasions but
other drug use) used a great deal more (P<0.001) cocaine and LSD, and
significantly more (P<0.05) tobacco, amphetamine and psilocybin mushrooms
than 'controls'. 33% of Heavy Ecstasy users had experience with
Barbiturates, 50% with solvents. 25% of all E users had taken opiates
before - we are not told why they used them; self-medication?
pharmacotherapy? 5. No drug screens (hair or urine) were performed on the day of testing so we have to take their word that subjects were drug free when assessed. I wish they had asked when was the last time the subjects had taken Ecstasy, or any drug for that matter, they could have separated their groups up in those terms and seen whether the observed results were a 'come-down' effect, 'mid-week' effect or long term effect. It would have also been useful to ask them where they take their drugs considering all that is known about the night club environment and also when they last went to a club and how frequently they attend clubs; chronic circadian rhythm disruption from frequent all-night party attendance will have an adverse effect upon all manner of health aspects. It is reported that E users had significantly greater self-reported disruptions in sleep (although the table of results does not support this :- typing error?) which may underlie some symptoms and may be reflective of recent night-club attendance (and perhaps also of recent drug use?) 6. I've not come across the SCL-90 questionnaire before. It is used as a clinical symptom self-rating scale for psychiatric out-patients, so how appropriate it is to use it as an assessment of a non-clinical sample is not clear. I'm not sure whether the scale has been validated in a community sample such as this or for that matter what the general population scores on the various subscales.The uplift/hassles questionnaire (results not mentioned in abstract), in particular 'cognitive failures', yielded no differences between groups, Parrott suggests that this is because users are not aware of their own deficits but equally it may be possible that psychobiological problems remain an artifact of the rating scales - users simply aren't affected by them and have noticed no change in their performance. Equally, users may believe that recent drug use may have caused current mental state and adjust their answers accordingly. 7. IVE impulsivity measures, this is something I wrote for another piece: "Questionnaire assessment of impulsivity in human Ecstasy users has so far been equivocal, with some authors reporting that users are less impulsive (McCann et al, 1994) whilst others that they are more impulsive than controls (Morgan 1998; Parrott et al., 2000). Using the Matching Familiar Figures Test (MFF20), Morgan (1998) suggested that users of Ecstasy exhibited greater impulsive behavior than both poly-drug and non-drug using controls as a result of reduced levels of serotonergic function. This latter set of data suggests that exposure to Ecstasy may possibly affect inhibitory control function and, as hypothesized by Jentsch and Taylor (2000), like other drugs of abuse may diminish the cognitive inhibition of impulsive behavior. However, it is also equally possible that differences may be the cause of Ecstasy use in the first place rather than a result. It is well known that drug abuse is associated with impulsive personality traits (Zuckerman et al., 1988; Reed et al., 1999) and decreased serotonergic function is a common feature in individuals with clinically relevant impulsive personality traits (Zuckerman, 1986; Coccaro et al, 1992). Therefore, are individuals with pre-existing serotonergic hypofunction and pre-morbid impulsive personality traits prone to use Ecstasy? Accordingly, are such individuals overrepresented in self-reported and behavioral tests of impulsivity in drug users? Furthermore, Evenden (1999,2000) opines that questionnaire measures of impulsivity are more suited for assessment of stable personality traits so it is unclear how applicable they are to the supposed more recent Ecstasy induced variations in impulsivity." Smokers of tobacco are more impulsive than non-smokers (Mitchell - psychopharmacology 1999 146:455-464) so Parrott's results may be due to the fact that around 87% of his ecstasy users smoked cigarettes compared to only 50% of controls. 8. An interesting point is made by Parrott on p109 "Many psychopharmacologists would not be too surprised at the current findings...,since the regular use of amphetamine and/or cocaine can lead to various psychobiological problems". Exactly, and his population were users of amphetamine and cocaine, so how can he relate his results to MDMA alone? Additionally, "The message that regular MDMA-use causes problems, needs to be incorporated into drug education packages. This information may also help those who develop psychiatric symptoms. At the moment, they may consider themselves unlucky or atypical and be afraid of seeking professional advice since their problems are self inflicted". I certainly agree with the provision of information to users about potential risks associated with excessive use of any drug but I do not see how further misinterpretation of data can help them. They are already bombarded with campaigns pertaining to the long term effects of Ecstasy use. Users may mistakenly attribute psychiatric problems to their drug use simply because they are continually informed by the media that Ecstasy has "damaged their brain" or "made them stupid"- the problem may be entirely unrelated to any drug use whatsoever. Users are not provided with unbiased presentation of scientific data by the media and the majority are not trained to disseminate and interpret results. If a user develops a psychiatric disorder that it is affecting their day to day life, relationships, work, etc., then I think that they will seek treatment regardless of whether it is a result of drug use or not. Hope this helps, please ask if you want any specific details as I've just rushed through the paper and mentioned only what caught my eye Best wishes, Harry Sumnall
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