August 2014 Newsletter

The recent death of Robin Williams is incredibly sad. As always, when a celebrity dies, especially when substance use is somehow involved, there is a lot of talk about the dangers of drug use and how addiction so often leads to death. I have a slightly different take on the issue: life long substance use disorders, where there is a constant battle against relapse - are usually the sign of something severe that underlies the SUD.

In this case, it seems, the monster below the surface was unresolved pathological depression. Of course, that mixed with an alcohol use disorder is a recipe for disaster. But the alcohol is an adjunct - it is both the (temporary) solution, and the (long-term) catalyst. It is not the primary disease.

I often see how by focusing on the SUD the real pathology is missed. Each relapse brings around renewed focus on the SUD rather than sparking the question: "Well, we know that SUDs die a natural death in most cases, unless there is a contributing factor, this person is not getting better, so what is the contributing factor, and how do we resolve that?"

It is sad that complex problems get reduced to the simple statement "Oh, he was an alcoholic".

In this newsletter I bring together some information from different types of addiction and drug use. When put together much of the research seems to be stating the obvious and, in my opinion, addiction looks more like a learning disorder or adaptive process and not a primary disease of the brain. It seems that Maia Szalavitz agrees with me.

We look at Marijuana and brain changes and schizophrenia, methamphetamine and brain changes, porn and brain changes, internet addiction (and brain changes), Tom Hovarth and SMART Recovery, the results of the Global Drug Survey. I hope you enjoy, and please feel free to comment! Please click HERE to find out more about the Cape Town Recovery Film Festival 2014.


Marijuana Madness!
Earlier this year there was a study published in the Journal of Neuroscience entitled "Cannabis Use Is Quantitatively Associated with Nucleus Accumbens and Amygdala Abnormalities in Young Recreational Users" and predictably the press went crazy. There followed a spate of alarmist headlines. Reuters reported in a headline that implied certainty that "Casual pot use causes brain abnormalities in the young:study". Fox News was slightly less certain with their headline "Casual marijuana use linked with brain abnormalities, study finds". It is embarrasing listening to this cringe-worthy interview with their "expert" who makes some massive leaps in logic.

The study, conducted at Northwest University conducted MRI scans on 20 casual Cannabis users and 20 controls. They conducted three analyses to detect structural differences on the nucleus accumbens and amygdala by looking at gray matter density via voxel-based morphometry, volume and shape. They found (from the abstract):
 "Gray matter density analyses revealed greater gray matter density in marijuana users than in control participants in the left nucleus accumbens extending to subcallosal cortex, hypothalamus, sublenticular extended amygdala, and left amygdala, even after controlling for age, sex, alcohol use, and cigarette smoking. Trend-level effects were observed for a volume increase in the left nucleus accumbens only. Significant shape differences were detected in the left nucleus accumbens and right amygdala. The left nucleus accumbens showed salient exposure-dependent alterations across all three measures and an altered multimodal relationship across measures in the marijuana group." 
and concluded:
 "These data suggest that marijuana exposure, even in young recreational users, is associated with exposure-dependent alterations of the neural matrix of core reward structures and is consistent with animal studies of changes in dendritic arborization"
From this one may start thinking that maybe there is a greater-than-observed risk in having the odd joint. However, very soon the study was discredited on many fronts, and one of them from an unexpected source - one of the co-researchers. Although he did not directly criticise the study itself, Dr Jodi Gilman, stated that they did not claim a causitive correlation between canabis use and the observed brain differences. However, if you read the article, this is what they do claim, right up until the second-last paragraph where there is a sudden about-turn.

But this is not the only problem with this piece of research. Rather than go into it here, I would suggest that you read this great and detailed blog post by Professor Lior Pachter of Berkley. The good professor states: "This is quite possibly the worst paper I have read all year......" and then he proceeds to rip it apart on a number of levels.

So, once again, a badly written and poorly reviewed article combined with a few sensationalist headlines in the popular press will further stigmatise drug users and present the unproven as "fact". 

Schizophrenia and Pot
Talking of correlation and causation, there has long been heated debate around whether cannabis causes or precipitates schizophrenia. While we know that there is a correlation between schizophrenia, is it causal? A previous study has cautiously suggested that the link may be both ways. Many have argued that it is causal, and this has formed one of the arguments against legalisation. Last year a Harvard study concluded that the levels of schizophrenia in cannabis users was due to familial risk, and not due to cannabis use.

Taking things a step further, a recent study in Molecular Psychiatry looked at a sample of 2 082 unrelated healthy males in Australia. The genotype for each individual was obtained. This data was compared with Swedish data which had previously identified a number of Single Nucleotide Polymorphisms that seem to indicate an increased risk of developing schizophrenia.

In a really clever second part of the study the researchers looked at the genetic risk of 990 twins (approximately 1/3 mono-zygotic) and then predicted whether one or both twins would use cannabis!

A significant association between level of genetic predisposition for schizophrenia and cannabis use was found. Having said this, the genetic risk is a small factor in developing a cannabis habit. What the authors did conclude was: "that to some extent the association between cannabis and schizophrenia is due to a shared genetic aetiology [cause] across common variants. They suggest that individuals with an increased genetic predisposition to schizophrenia are both more likely to use cannabis and to use it in greater quantities."

 Of course, being a cross-sectional study there are limitations, and the authors also point out a number of other possible confounders and limiters. Interesting though that there were no huge headlines proclaiming "Schizophrenia Causes Cannabis Use!".

And as for that nature versus nurture debate, it is increasingly becoming clear that it is a false dichotomy.

Methamphetamine and Cognitive Impairment
The "controversial" but always thought provoking Dr Carl Hart recently published a critical review on cognitive impairment in methamphetamine users. Once again the ability to assign causation in cross-sectional studies comes into question. While Dr Hart certainly has an agenda, as the recuring themes of his work suggest, he makes some excellent points in his review of a variety of studies that examine cognitive function in methamphetamine users. He examines studies in a number of areas: Acute effects on drug naive and drug accustomed subjects, long-term effects on current and abstinent drug users, the brain structures and sizes of currently abstinent methamphetamine users and comprehensive neuropsychological testing of abstinent abusers.

While Hart acknowledges that there are some "brain changes", particularly in the area of dopamine transporter density in animal studies and that striatal binding potentials were lower in human subjects, this did not translate into clinically significant behavioural changes. The same was found regarding the gray and white matter structural changes observed in some studies.

Hart effectively highlights many of the weaknesses in these studies and makes a valid conclusion:
"Many researchers in this area begin with the assumption that methamphetamine abusers exhibit cognitive dysfunction, and that their research bears this out. Findings from this review suggest that this assumption should be reevaluated to document the actual pattern of cognitive effects caused by the drug."
Certainly my experience with treating high dose meth users is that they do not seem to suffer any long-term cognitive defects, and certainly there is no problem using cognitive based therapies. There is some evidence emerging though that shows that cognitive training can improve outcomes for treatment, although I think we will find this to be true across all addictive behaviours.

Having said that, there is little doubt that drug use changes the brain - as does virtually everything else, reading, for example - but is this permanent or as extreme as is believed by many? And who said "change" was bad? It is this neural plasticity that allows us to learn, grow and sometimes recover from brain traumas. Is brain change a sign of disease? I don't think so.....

Porn and the brain
Porn has been in the headlines again...more specifically porn addiction. Something that the DSM5 has deemed not an addiction (at this point in time) but certainly looks like an addiction and shares many neural correlates, as I have previously discussed in two posts: relationships and addiction and sexual addiction and drug addiction. Now a study led by Dr Valerie Voon and published on PlosOne has shown that when viewing pornography, the brains of sex addicts look remarkably like the brains of drug addicts. Who would have guessed. Well, quite a few of us actually.

Using fMRI, the subject's brains were scanned while watching a series of videos of 5 varying degrees of eroticism and other content. Through self report the researchers tried to quantify subjective experience of "wanting" and "liking". These are important concepts explored by the work of Kent Berridge, and the distinction is important in the field of addiction. As predicted, the "wanting" was more important than the "liking" in those that were considered to have compulsive sexual behaviour, and there was greater activation in the "regions implicated in drug cue reactivity studies including the ventral striatum, dACC and amygdala. We further hypothesized that these regional activations would be functionally linked across groups but more strongly in individuals with compulsive sexual behaviour (CSB) as compared to those without, and that sexual desire (wanting) would be more strongly linked to activity within these regions in individuals with CSB as compared to those without."

So porn addiction is neurologically, to some degree, much like some aspects drug addiction. This to me is obvious because it can easily be seen that the behaviours are really similar, and so one would expect neural correlates. But does it cause cognitive impairment? A recent German study is speculating a loss of "brain power" in sex addicts due to "over-stimulation of the reward centre".

Like with many of the methamphetamine studies, the authors found negative association between hours viewing porn per week and "gray matter volume in the right caudate (P  < .001, corrected for multiple comparisons) as well as with functional activity during a sexual cue–reactivity paradigm in the left putamen (P < .001). Functional connectivity of the right caudate to the left dorsolateral prefrontal cortex was negatively associated with hours of pornography consumption."

I wonder what this means for all those hyper-sexual methamphetamine users? Are they doubly cognitively impaired, or is addiction simply addiction with multiple manifestations? 

It certainly appears so when we look at the rise of internet addiction:

Internet and Gaming Addiction
Gaming and internet addiction also did not make the cut into the DSM5.
In a recent Fix article they discussed the Sun's antagonistic headline "Gaming as Addictive as Heroin" and one of the experts consulted for the article refuting the claim. What I find interesting is that the expert, Dr Mark Griffiths of the International Gaming Research Unit at Nottingham Trent University, does not refute the existence of gaming addiction, but that only a minority of problematic game users could be classified as "addicted". I would agree with that.

Where we may differ is that I would argue that the same is true for drug addiction - problematic drug use does not equal addictive drug use, and it is only a small minority of drug users that actually become addicted.

Closely linked with gaming addiction is internet addiction, which is also being shown to change the brain! In a recent Medscape Article a paper presented at American Psychiatric Association's 2014 annual meeting is discussed. I could have guessed that internet addiction is linked to a reduction in dopamine transporters. And from a 2012 study "Internet addiction is associated with structural and functional changes in the brain regions involving emotional processing, executive attention, decision making and cognitive control."

Although internet addiction is looking a lot like other types of addiction, lets hope that treatment doesn't go back to the punitive abstinence based approach that forms the basis of many addiction treatment facilities. It looks like that is the route that the Chinese will be taking if this New York Times video is anything to go by!

Tom Horvath and SMART Recovery
Tom Horvath, PhD is strong voice in the field of addiction treatment. Way back in 1985 he founded Practical Recovery which offers a much-needed alternative to the 12-step models that dominate the treatment field. Anne Fletcher, in her book Inside Rehab, describes Practical Recovery's approach as completely different from that of other programs.

Not only is Dr Hovarth the founder and president of Practical Recovery, but he is also president of SMART Recovery, the international nonprofit that offers free, self-empowering, science based mutual help groups for addiction recovery. SMART has over 20 to 30 000 members world-wide.

In both treatment modalities that Tom oversees the power is vested in the individual - there's no talk of being powerless in the face of addiction. Recently SMART Recovery has started meetings in Cape Town, and I am hoping that these find traction in my local setting where this type of intervention is much needed.

Global Drug Survey Data
The global drug survey aims to collect data from drug users around the world. It all started 15 years ago as a simple questionaire in a clubbing magazine and has now grown to an international web-based survey.

Filled with some fascinating pieces of information, such as cocaine was voted the worst value for money drug and MDMA the best, the results of the 2014 Global Drug Survey are out. The data was collected from nearly 80 000 self-selected participants around the world. Worth a look even if the sample is not truly representative.

One of the key messages from the survey was that current drug laws are a barrier to people seeking help for problematic drug use. The Huffington post talks more about this issue here.

http://capetownrecoveryfilmfestival.com/





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