How to read and understand cannabis science
By Richard Shrubb
NORML recently posted a link to a blog on Facebook. The blog in question suggested that cannabis can be beneficial to bipolar disorder. On one line of thinking this is very interesting – cannabis is a nice sedative, and I have seen studies that show it can actually be good at treating psychosis. This fed my interest.
One of my specialisms is as a medical science journalist, so I looked at the study myself. What came up led to a bit of a dingdong on the Facebook page, because the bloggers writing the piece overlooked a key part of the study – that the group who used cannabis had a far higher prevalence of psychosis than the non using group. In short, yes it does have some favourable results in treating bipolar disorder, but there is a high risk of psychosis.
Reading science is key for a movement that has science used against it so rabidly and effectively. The Mail raves incontinently seemingly every week about cannabis “causing schizophrenia”, which when you speak to the scientists that the Mail quote, you tend to find is nothing short of bollocks. Scientists working in that field who are unfortunate favourites of the right wing press live in fear of headlines taking some half truth from their studies and blowing it into supposed fact.
I have paranoid schizophrenia. I was led to believe it was caused by smoking weed. Only through my journalism did I learn that people with psychosis shouldn’t touch it, and if you even get paranoid smoking it, you should leave it alone. I also learned that there is little to fear in most people having the odd joint. More to the point, cannabis does NOT cause schizophrenia.
In order to respond effectively to broadsides from the Mail and selective use of science from MP’s, people need to understand how to read science and thus to respond effectively. I work closely with leading science journalist Dr Toby Murcott. He has kindly responded to some basic questions about “reading science”.
For all we know, then Prime Minister Gordon Brown was talking to his Dad’s boss (God) when he had the revelation that cannabis causes schizophrenia – no scientist would ever say that! According to Dr Murcott, science “has important limits. Firstly, science cannot prove something, it can only disprove. This means that you cannot say to science “prove to me that (insert your own pet theory here)”, which is what many politicians would like.”
Science can never prove. As Dr Murcott says, “Einstein’s Theories of Relativity are still being tested to this day, even though they have survived every attempt to knock them over so far. Any scientist who succeeds in finding a chink in its armour will be praised and may well win a Nobel Prize.“ What we accept as “incontrovertible proof” from the best physicist of the last century, may well be disproved in our lifetime!
Moving back to the world of weed, there is a lot of anecdote that cannabis can wipe out cancer tumours. Many people say this is incontrovertible. I understand that there is a group of scientists taking this anecdote and trying to show it scientifically. Just because you “know” it to be true, unless scientists test your ideas there will be no way you will get a THC spray for your lung cancer any time soon. People who believe strongly enough that weed can cure their lung cancer may actually recover. There is a massive amount of work being done on so called “placebo”, an inert chemical that is taken in the sincere belief it is a wonder cure, and the body fixes the problem purely on the belief it is true. Until I read something that said it takes 20 minutes to get your fix from an e-cigarette I believed I was getting the hit instantly. Reading that text destroyed my belief and now I don’t get a hit from e-cigarettes. That bloody research may have shortened my life by a decade.
Dr Murcott explains the difference between anecdote and research, “imagine you know nothing about astronomy and you sit in a field from sunrise to sunset. If you were asked whether the Sun goes around the Earth or the Earth around the Sun, the evidence of your eyes will clearly tell you that the Sun goes around the Earth.” Science however has shown us that the earth spins and travels around the Sun, providing day, night and seasons.
Generally in medical research the bigger the number of participants – the “cohort” – the better the piece. Dr Murcott says, “the crude rule of thumb is the more patients the drug or treatment is tested on, the more reliable the results are likely to be.”
So, if everyone in the UK participated in a cannabis and schizophrenia study – say 60 million people – you would find that 1% get schizophrenia. This is core to my understanding of the links between cannabis and schizophrenia. Since the 1960’s several tens of millions of people have abused psychedelics yet the rate of schizophrenia hasn’t even wobbled globally. I’m sure if everyone in the UK got stoned for a month in a badly made study, the Mail would point to the 1% and say “cannabis causes schizophrenia in 1%”! This is why scientific research has to be designed properly. Likely you’d have three groups of 20 million – one group of stoners, another smoking THC free hemp, and the third smoking nothing at all. You would compare the rates of mental illness among all three groups and could draw your conclusions.
Why does medical research take so long? It seems frustrating. But if you gave out a drug that yes, wiped out a lung tumour but drove everyone who took it so nuts they jumped off Beachy Head, you wouldn’t be saving lives. I’ve taken a drug that helped stop my alcoholism but it made me psychotic for five years. I’m lucky to have a career, let alone a life.
Research goes through three phases over around a decade if all goes well. Most drugs fail in testing. Dr Murcott explains the three phases:
“Phase One. This is the first time a drug has been tried in humans and the purpose is to ensure that it is safe.”
“Phase Two. This is the first time the drug will have been tried in human patients who have the condition it is designed to treat. A group of suitable patients will be selected and then divided at random into two or more groups. One group will get the experimental drug, and the other groups may get an established treatment or a placebo depending on the design of the trial. Normally the drug will have to show it is both more effective than a placebo and the current treatments before moving to Phase Three.”
He continues, “Phase Three. This is the real crunch. Depending on the drug and the condition the drug will be tested on large numbers of patients, often many thousands. This is point at which the drug has to show it offers real improvements over current treatments both in terms of safety and efficacy against the condition it’s designed to treat.”
Phase Three is at a very large scale. The antipsychotic I take has a 50% increase in chance of the patient becoming obese. It also has a 3% rate of diabetes – above the normal rate of 2% in ordinary people. The authorities will weigh up the risks of diabetes against the benefit of the drug. I’ve made the choice to try to live a lifestyle that reduces the risks of diabetes but am happy that the drug doesn’t make me twitch uncontrollably or sedate me so much I am a bloody zombie like the drugs of the 1970’s did. Because I am not a twitching zombie I can function in society – exactly what the drug was designed to do. The risks weighed up? Olanzipine got through Phase Three trials and was licensed.
In another interview, Dr Murcott told me “science is about being nosy”. All scientists do is test something to destruction. Unfortunately different designs and motivations behind research find different things. At the moment with regard research on cannabis you can do as one MP did recently on the request of NORML and be selective as to which research you read and choose to believe.
Because science is inexact in regards cannabis, people can believe what they want to and generally come up with the research to prove their own beliefs. Yes cannabis can cause psychosis. It only causes psychosis in a certain group of people and no one understands why Chris can smoke bath bongs all day and be OK where Peter loses it on one toke of a spliff. Until someone designs a study that explains this, which can be repeated at a large scale a dozen times, it is for those to choose their beliefs. At the minute, the Daily Mail (readership, 3 million) has a delusion it seeks to prove every day (like I do my psychotic delusion) and MP’s read it as well as the poor souls who waste their money at the newsagents. Until something utterly incontrovertible comes? Learn to read science well, and derive your own opinions!
Richard Shrubb is a freelance journalist with a specific interest in medical science and sailing, for more info about Richard, see his web site www.richardshrubb.co.uk and you can follow Richard on Twitter #Shrubberz