Showing posts with label methylphenidate. Show all posts
Showing posts with label methylphenidate. Show all posts

Sunday, March 2, 2014

Cognitive Enhancement IS Cheating

One of my colleagues posted a recent commentary from Nature on how the idea of the smart pill has been oversold.  The basic theme of the commentary is that there is no good evidence that treatment of ADHD with stimulants improves academic outcomes.  The author reviews a few long term studies and contends that differences between the medication and placebo seem to wash out over time and therefore there is no detectable difference.  Her overall conclusions seem inconsistent with her view that:  "For most people with ADHD, these medications — typically formulations of methylphenidate or amphetamine — quickly calm them down and increase their ability to concentrate. Although these behavioural changes make the drugs useful, a growing body of evidence suggests that the benefits mainly stop there..."

A question for any cognitive psychologists out there - is it possible to improve your concentration and have that not improve learning?  I can't imagine how that happens.  If you go from not being able to read 2 pages at a time to suddenly reading chapters at a time, how is that not enhanced cognitive performance?  If you go from staring out the window all day and daydreaming to being able to focus on what the teacher is saying how will that not lead to an improved outcome?  The idea that improved attention - a central factor in human cognition will not affect anything over time suggests to me that the measures being used for follow up are not very robust or that this is a skewed sample of opinion.   

For the purpose of cognitive enhancement, the typical users are students trying to gain an edge by increasing their study time.  Anyone who has experienced college and professional school realizes that here is a large amount of information to be mastered and it is not presented in an efficient way.  I can never recall a professor who advised us of the important guideposts along the way or gave us any shortcuts.  The usual message is study all of this material in depth every day or you will fall behind.  That approach in general is consistent with gaps in the ability to study either through the normal course of life or the competition for intellectual resources by 3 or 4 other professors who regard their courses as important.  That typically results in a pattern of cramming for specific key exams.  Although I have not seen any specific studies, stimulant medications are generally used for this purpose and in many cases the use is widespread.  There is a literature on the number of college students who may be feigning ADHD symptoms in order to get a prescription and that number could be as high as 50% (4,5). 

What  about the issue of stimulants acting as a smart pill in people who don't have ADHD?  In the most comprehensive review I could find on the subject (6) the authors review laboratory studies and conclude that in those settings stimulants enhance consolidation of declarative learning to varying degrees, had mixed effects on working memory, and mixed effects on cognitive control.  On 8 additional tests of executive function, the authors found that stimulant medication enhance performance on two of those tests - non-verbal fluency and non-verbal intelligence.  They have the interesting observation that small effects could be important in a competitive environment.  Their review also provides an excellent overview of the epidemiology of stimulant use on campuses that suggests that the overall prevalence is high and the pattern of use is consistent with cramming for exams.  They cite a reference that I could not find (7) that was a reanalysis of NSDUH data suggesting that as many as 1 in 20 stimulant users may have a problem with excessive use and dependence.     

Getting back to the theme of the Nature commentary, it is ironic that the smart pill theme is being called into question when it was the subject of a Nature article years earlier advocating for the use of cognitive enhancement.  In that article Greely, et al come to the somewhat astounding conclusion: 

"Based on our consideration, we call for a presumption that mentally competent adults should be able to engage in cognitive enhancement using drugs."

They arrive at that conclusion by rejecting three arguments against this practice.  Those arguments include that it is cheating, it is not natural and it is drug abuse.  Their rejection of the cheating argument is interesting because they accept the idea that performance enhancing drugs (PEDS) in sports is cheating.  They reject that in cognitive enhancement claiming that there would need to be a set of rules outlining what forms of enhancement would be outlawed and what would not (e.g. drugs versus tutors).  To me that seems like a stretch.  I think that sports bodies select performance enhancing drugs as a specific target because it clearly alters body physiology in a way that cannot be altered by any other means.  There is also plenty of evidence that the types of PEDS are dangerous to the health of athletes and associated with deaths.  Their conclusion about drug abuse: "But drugs are regulated on a scale that subjectively judges the potential for harm from the very dangerous (heroin) to the relatively harmless (caffeine).  Given such regulation the mere fact that cognitive enhancers are drugs is no reason to outlaw them."   That is a serious misread of the potential addictive properties of stimulants and the previous epidemics that occurred when the drugs were FDA  approved for weight loss, the epidemic of street use in the 1970s and the current and ongoing epidemic of meth labs and methamphetamine use throughout much of the USA.

These authors go on to outline four policy mechanisms that they believe would "support fairness, protect individuals from coercion, and minimize enhancement related socioeconomic disparities."  At first glance these lofty goals might seem reasonable if society had not already had in depth experience with the drugs in question.  The clearest example was the FDA approved indication of amphetamines for weight loss.  What could be a more equitable application than providing amphetamines to any American who wanted to use them for weight loss?  The resulting epidemic and reversal of the FDA decision is history.  A similarly equitable decision to liberalize opioids in the treatment of chronic pain had resulted in another epidemic of higher lethality due to differences in the toxicology of opioids and amphetamines. 

The contrast between these two commentaries in Nature also highlight a couple of the issues about the way medical problems and treatment is portrayed in the media.  This first is that you can't have it both ways.  Quoting a researcher or two out of context does not constitute an accurate assessment of the science involved.   Some of the authors in the first commentary are highly respected researchers in cognitive science and they clearly believe that cognitive enhancement occurs and it should be widely applied.  Nature or any other journal cannot have it both ways.  A more realistic appraisal of the problem is addressed in reference 6.   The second issue is that in both cases the authors seem blind to the addictive properties of stimulants and they are ignorant of what happens when there is more access as exemplified by the FDA misstep of approving stimulants for weight loss.  Do we really need a new epidemic to demonstrate this phenomenon again?  Thirdly, all of this comes paying lip service to non - medication strategies for cognitive enhancement.  We can talk about the importance of adequate sleep - a known cause of ADHD like symptoms and if we are running universities and workplaces in a manner that creates sleep deprived states, the next step is reaching for pills to balance an unbalanced lifestyle.  The new rules for residency training are a better step in the right direction.  Fourth, college is a peak time for alcohol and substance use in the lives of most Americans.  These substances in general can lead to a syndrome that looks like ADHD.  It is highly problematic to make that diagnosis and provide a medication that can be used in an addictive manner.  It is also highly problematic to think that treating an addicted person with a stimulant will cure them of the addiction and yet it happens all of the time.

There is plenty of evidence to suggest that cognitive enhancement is cheating.   Much of my career has been spent correcting the American tendency of trying to balance one medication against another and using medications to tolerate a toxic lifestyle or workplace.  It does not work and the current group of medications that are being put forward as cognitive enhancers are generally old drugs with bad side effect profiles particularly with respect to the potential for addiction.

If you want safe cognitive enhancers that can be made widely available, they have not been invented yet.  

George Dawson, MD, DFAPA




References:

1: Sharpe K. Medication: the smart-pill oversell. Nature. 2014 Feb 13;506(7487):146-8. doi: 10.1038/506146a. PubMed PMID: 24522583.

2: Greely H, Sahakian B, Harris J, Kessler RC, Gazzaniga M, Campbell P, Farah MJ.
Towards responsible use of cognitive-enhancing drugs by the healthy. Nature. 2008 Dec 11;456(7223):702-5. doi: 10.1038/456702a. Erratum in: Nature. 2008 Dec 18;456(7224):872. PubMed PMID: 19060880.

3: Feldman HM, Reiff MI. Clinical practice. Attention deficit-hyperactivity disorder in children and adolescents. N Engl J Med. 2014 Feb 27;370(9):838-46. doi: 10.1056/NEJMcp1307215. PubMed PMID: 24571756.  

4: Green P, Lees-Haley PR, Allen LM., III The word memory test and the validity of neuropsychological test scores. J Forensic Neuropsychol. 2002;2:97–124. doi: 10.1300/J151v02n03_05

5: Suhr J, Hammers D, Dobbins-Buckland K, Zimak E, Hughes C.  The relationship of malingering test failure to self-reported symptoms and neuropsychological findings in adults referred for ADHD evaluation.  Arch Clin Neuropsychol. 2008 Sep; 23(5):521-30.

6: Smith ME, Farah MJ. Are prescription stimulants "smart pills"? The epidemiology and cognitive neuroscience of prescription stimulant use by normal healthy individuals. Psychol Bull. 2011 Sep;137(5):717-41. doi: 10.1037/a0023825. Review. PubMed PMID: 21859174 

7: Kroutil LA, Van Brunt DL, Herman-Stahl MA, Heller DC, Bray BM, Penne MA. Nonmedical use of prescription stimulants in the United States. Drug and Alcohol Dependence. 2006; 84:135–143.10.1016/j.drugalcdep.2005.12.011 [PubMed: 16480836]


Wednesday, December 12, 2012

ADHD and Crime

There has been a lot of commentary on the NEJM article on the association between stimulant treatment of Attention Deficit Hyperactivity Disorder (ADHD) and less crime in a cohort of patients with ADHD.  Two of my favorite bloggers have commented on the study on the Neuroskeptic and Evolutionary Psychiatry blogs.  As a psychiatrist who treats mostly patients with addictions who may have ADHD and teaches the subject in lectures - I thought that I would add my opinion.

Much of my time these days is spent seeing adults who are also being treated for alcoholism or addiction. I also teach the neurobiological aspects of these problems to graduate students and physicians.  In the clinical population that I work with - ADHD is common and so is stimulant abuse/dependence and diversion.  Cognitive enhancement is a widely held theory on college campuses and in professional schools.  That theory suggests that you can study longer, harder, and more effectively under the influence of stimulants.  They are easy to obtain.  Stimulants like Adderall are bought, sold, and traded.  It is fairly common to hear that a feeling of enhanced cognitive capacity based on stimulants acquired outside of a prescription is presumptive evidence of ADHD.  It is not.  It turns out that anyone (or at least most people) will have the same experience even without a diagnosis of ADHD.

There is very little good guidance on how to treat ADHD when stimulant abuse or dependence may be a problem.  Some literature suggests that you can treat people in recovery with stimulants - even if they have been previously addicted to stimulants.  Anyone making the diagnosis of ADHD needs to makes sure that there is good evidence of impairment in addition to the requisite symptoms.  Ongoing treatment needs to assure that the stimulants are not being used in an addictive manner.  I would define that as not accelerating the dose, not taking medications for indications other than treating ADHD (cramming for an exam, increased ability to tolerate alcohol, etc), not attempting to extract, smoke, inject, or snort the stimulant, not obtaining additional medication from an illegal source, and not using the stimulant in the presence of another active addiction.  Addressing this problem frequently requires the use of FDA approved non stimulant medication and off-label approaches.

With the risk of addiction that I see in a a population that is selected on that dimension, why treat ADHD and more specifically why treat with medications?  The literature on the treatment of ADHD is vast relative to most other drugs studied in controlled clinical trials.  There have been over 350 trials and the majority of them are not only positive but show very robust effects in terms of treatment response.  The safety of these medications is also well established.

Enter the article from the NEJM on criminality and the observation that stimulants treatment may reduce the criminality rate.  This was a Swedish population where the research team had access to registries containing data on all persons convicted of a crime, diagnosed with ADHD, getting a prescription for a stimulant, and to assign 10 age, sex, and geography matched controls to each case.  Active treatment was rather loosely defined as any time interval between two prescriptions as long as that interval did not exceed six months.  The researchers found statistically significant reductions during the time of active treatment for both men (32%) and women (41%).      

I agree that this is a very high quality article from the standpoint of epidemiological research - but my guess is the editors of the NEJM already knew that.  This study gets several style points from the perspective of epidemiological research.  That includes the large data base and looking for behavioral correlates of another inactive medication for ADHD - serotonin re-uptake inhibitors or SSRIs.  There is a robust correlation with stimulants but not with self discontinued SSRIs.  They also analyzed the data irrespective of the order of medications status to rule out a reverse causation effect (treatment was stopped because of criminal behavior) and found significant correlations independent of order.

Apart from the usual analysis clinical and researchers in the field ranging from neurobiologists to researchers doing long term follow up studies do not find these results very surprising.  The Medline search below gives references of varying quality dating back for decades.  The pharmacological treatment certainly goes back that far.  The accumulating data suggests that where the disorder persists, it requires treatment on an ongoing basis.  A limited number of studies suggest that cognitive behavioral therapy (CBT) may be useful for adults with ADHD but not as useful for children or adolescents.  The practice of "drug holidays" prevalent not so long ago - no longer makes sense when the diagnosis is conceptualized as a chronic condition needing treatment to reduce morbidity ranging from school failure to decreased aggression to better driving performance.

One of the typical criticisms of epidemiological research of this design is that association is not causality, I think it is time to move beyond that to what may be considered causal.  In fact, I think it may be possible at this time to move beyond the double blind placebo controlled trial to an epidemiological standard and I will try to pull together some data about that approach.

George Dawson, MD, DFAPA

Lichtenstein P, Halldner L, Zetterqvist J, Sjölander A, Serlachius E, Fazel S, Långström N, Larsson H. Medication for attention deficit-hyperactivity disorder and criminality. N Engl J Med. 2012 Nov 22;367(21):2006-14. doi: 10.1056/NEJMoa1203241.

Criminality and ADHD:  Medline Search