I was asked to consider writing a post on mental illness and links (if any) to cannabis. I’ll be honest, I did wonder whether the debate behind that and all of the science that goes with it was not just a bit above my pay-grade? Then I learned something about a policing incident in which I was extremely interested which opened this up for me so I thought I’d put down a few thoughts:
Over the last few years, the UK has been on something of a journey regarding cannabis. When I joined the police, it was a Class B drug under the Misuse of Drugs Act 1971 – this legislation governs our society’s approach to drugs to this day. In 2004 it was re-classified to a Class C drug on advise from the Advisory Council on the Misuse of Drugs. However, it was re-classified in 2009 to Class B for what were described by the Chair of the Council, Professor David NUTT, as ‘political reasons’. He had previously described cannabis as “less harmful than alcohol or tobacco” but the re-classification decision went ahead, called for by some senior police officers and supported by the Home Secretary. This was despite the Council’s advice amidst a public debate which tried to link cannabis to the development of some psychotic conditions and longer-term mental health problems.
I once heard someone describe the taking cannabis as having all the joys of smoking like cancer with the “added bonus of mental illness”. And this was by a psychiatrist. In my career, I’ve met a lot of people who use cannabis; some of them to quite a startling degree. Throughout that time it has been “received wisdom” amongst many officers with whom I have worked that prolonged use of cannabis over many years can lead to mental health problems. But when it was declassified in 2004, this link was denied or deemed to be of little significance. This potential link was more acknowledged in 2009 when cannabis was reclassified although as stated, this was opposed by the Advisory Council. The dispute lead to the sacking of Professor NUTT and subsequent resignations by other members, in protest at the dismissal.
We know that cannabis is considered by some people with medical problems, to ease suffering. Some patients with multiple sclerosis have campaigned to have cannabis de-criminalised (as opposed to legalised) for use in the treatment of some medical conditions. Meanwhile, we know some patients with mental health problems report that cannabis can ease the impact of auditory hallucinations and other symptoms. Other patients have reported they cause them.
I am aware of some police interventions with people under the influence of cannabis which have lead to them being admitted to a hospital on the grounds of being mentally ill. I am aware that some of those led, just a few days later, to the person being released from care because the effects of drugs had worn off and it was no longer believed that they sufferred from a mental disorder. (I am also aware of a case where this occurred after a man drank a bottle of red wine having also taken over-the-counter medication to assist him to stop smoking – the two things produced a chemical effect which made him present to police officers as if he were mentally ill. The MHA assessment team agree and detained him s2 MHA.)
Of course, there are some examples of people who regularly use large amounts of cannabis being repeatedly detained by the police under emergency detention and sometimes admitted to hospital, only to continue a revolving door approach when the effects wear-off and psychotic behaviour dissipates. The ‘interesting case’ I referred to at the top involved a family complaining at a police decision to implement detention under mental health law (s136) but the assessing professinoals were also sufficiently satisfied by the man’s presentation in the (MHA) Place of Safety, to admit him s2 MHA for 28 days. Does this not validate the officers impressions, that experienced mental health professionals also thought he was mentally disordered and sufficiently to justify 28 day detention in hospital? Yes, in my view.
As I became interested in policing and mental health, I did a little bit of reading around this area and spoke to mental health professionals. There seemed to be consensus that excess cannabis use in some people can indeed induce temporary psychotic states and long-term use could lead to long-term problems. I have since seen studies (meta-analyses) which state that there could be as much of a three-fold risk of developing schizophrenia or a schizophrenia-like illness; and other studies make similar claims. It has also been suggested that substance abuse is a predictor of disengagement from psychiatric treatment. [I will shortly add links to studies which have been drawn to my attention implying the link between cannabis and mental health to be negligible.]
In discussion around this, I was once told an interesting statistic which I’ve tried out on a range of mental health and / or dual diagnosis professionals. (For those who don’t know, “dual diagnosis” means mental health and substance abuse problems.) The statistic was: that 90% of people with a dual diagnosis are patients with mental health problems who ‘self-medicate’ with drugs, including cannabis, and / or alcohol. 10% are people who have mental health problems, associated to their original abuse of substances. I’ve heard this expressed a few ways: 90/10, 80/20 or 70/30. But the point seems agreed anecdotally by those in the field, that most dual diagnoses are people developing substance abuse problems after self-medicating.
So my lay person’s impression is that if substance abuse leading to mental health problems is the minority of dual diagnosis conditions; and if substance abuse is predictive risk factor for disengagement from treatment, then addressing substance abuse problems is key to effective mental health strategies at the population level. When one then also thinks about the impact of alcohol on society … problematic.
A final point: police forces have often been asked – indeed, some have offered – to take drugs dogs into psychiatric facilities to help identify patients who possess illicit substances or to identify whether drugs have been brought in. Knowing a few dog handlers quite well, it’s fair to say that those who have done it have sometimes reported that the dog thought it was Christmas because every ‘find’ gets a reward (usually a toy, sometimes a snack). In some wards, no issues at all.
Reactions to suggestions by staff, or offers by police, that drugs dogs could be used to help with drugs problems have been mixed in my experience. I’ve seen some professionals argue it is highly inappropriate, but some have immediately found conflict with their colleagues who know there is a drug use (or even drug dealing) problem on the ward. In addition to pointing out that hospitals have a legal duty not to knowingly tolerate drug use or supply on wards (s8 Misuse of Drugs Act 1971), it is also relevant to point out that patients who do not wish to use or supply drugs find the presence of such factors on ward life to be extremely negative at an already difficult time. It contributes to feeling unsafe, amongst other things.
I’ve never had a view that cannabis is benign, notwithstanding its image in some quarters and the links to mental illness now seem more clearly understood. In the spirit of balance I will add links to studies which imply the link to be negligible, althought in the face of both sets and my own experience and various service users’ feedback, my instinct is away from them. It is also clear that substance abuse generally needs to be tackled for any mental health strategy to be successful at that population level and I’m not even vaguely satisfied that this is properly understood.
The main point of this blog is not to side particularly with one view or another – although you’ll clearly see where my personal instinct lies. If mental health professionals are sometimes mistakenly convinced or temporarily convinced that reaction to cannabis use is consistent with mental disorder; it must be accepted as reasonable that police officers will sometimes think this. Especially, this is the case where police decision-making must occur within minutes or seconds, rather than in an MHA interview which can take an hour or so. It has sometimes become necessary to ‘section’ people under the MHA for 28 days to fully work this stuff through.