Original: Tod durch Cannabis? Eine kritische Betrachtung by Maximilian Plenert, translated by Tim Gluckman.
On 25.2.2014 the article ‘Cannabis erstmals als Todesursache nachgewiesen’ (Cannabis proven for the 1st time to be cause of death) appeared in the Rheinischen Post (major German regional daily newspaper). In it Dr Benno Hartung, coroner and co-author of the underlying case-report which appeared in the specialist journal ‘Forensic Science International’, is quoted with the words, ”To the best of our knowledge these are the first cases of cannabis-caused death worldwide which have been examined entirely in accordance with state-of-the art scientific standards.’ He and his colleagues came to this conclusion after they found THC in the blood of the corpses; all other causes were in their opinion ruled out. The resonance of their report in the media was formidable, it even gained international attention. On closer examination the would-be proof evaporates and (such cases) are also not new.
The study can be scrutinised from various viewpoints. As well as criticism of the analysis itself, the risk supposedly established should also be considered in the entire debate (re legal cannabis).
1. Criticism of the Study itself
The examination by Hartung and colleagues displays many weaknesses. In particular the procedural method, “We have excluded everything else, as a result it must be cannabis,” is questionable. Furthermore one of the deceased suffered, for example, from a hypertrophic cardiomyopathy. Sudden cases of death of people younger than 35 commonly result from activity in sports, and an undiagnosed hypertrophic cardiomyopathy. In an email we shall ask Mr Hartung to respond to the points mentioned by ourselves and others.
Dr. med. Franjo Grotenhermen (International Association for Cannabinoid Medicines): ”One mostly finds no cause of sudden cardiac death, and if one then finds THC in those concerned, then it does indeed say nothing about the cause.”
In the weekly newspaper Die ZEIT Michael Tsokos, Director of Forensic Medicine at the Berlin hospital Charité, Frank Mußhoff from Forensisch Toxikoloischen Centrum (Forensic Toxicology Centre) Munich, and Prof. Rainer Thomasius, Director of the Deutschen Zentrums für Suchtfragen des Kindes- und Jugendalters (German centre for Addiction Research in Childhood and Adolescence) have already expressed their opinions.
In reply to ZEIT’s question: “Do the detailed post-mortem findings actually prove that both men died of hash?” Tsokos replied: “The individual findings do not support that.” “From them it emerges that the 23-year-old deceased had a serious cardiac pre-condition. If he had not by chance smoked cannabis the day before his death, a connection (of cannabis) with his death could not have been established (…) Cases in which the cause of death is unclear, occur regularly. To assume cannabis is the cause is for me a Verlegenheitsdiagnose (a diagnosis to prevent embarrassment / diagnosis ofconvenience).” Tsokos underlined: “This is all about a coincidence not causality.”
Mußhoff is quoted with the following words: “Since nothing more turned up after the analyses, Hartung and his team plumped for cannabis.” He referred to the lowq THC and THCOOH values in the blood of the deceased. These contra-indicate an ongoing state of intoxication.”
Prof. Rainer Thomasius – whom no-one could suspect of an affinity for cannabis, he is comparable with Prof Neil McKeganey – commented: “People with heart damage, dysfunctions of the lipid mechanism in blood, or vascular disease, have an increased likelihood of a heart attack if they smoke cannabis (…) That is, however, not a new perception (…).It concerns only a fraction of people and is very seldom.”
The former Chairman of the Advisory Council on the Misuse of Drugs (ACMD) Prof. David Nutt commented recently about a similar case of a “cannabis death” in Great Britain.
2. “How dangerous is cannabis?” is not the crucial question
Dr. Raphael Gaßmann stated during the Bundestag Hearing concerning ‘Cannabis Social Clubs’:
“From the point of view of the Deutschen Hauptstelle für Suchtfragen (German Centre for Addiction Issues) the crucial question is not whether cannabis consumption may make people dependent and whether it is damaging. The crucial question is that of the prohibition of cannabis. Does the cannabis prohibition have a positive impact? Does the ban result in fewer people taking it and that those who do consume it take less as a result of the prohibition? That is the crucial question, and not whether cannabis leads to dependency.”
In particular when the issue is a problem that occurs very rarely as in this case, or also the risk of testicular cancer which has supposedly increased by 70% given that per year there are 7 cases of testicular cancer for every 100,000 men.
3. Cannabis may damage health
The use of cannabis in particular when it is smoked and with tobacco, may lead to health problems. In particular the pregnant, people with schizophrenia or heart problems should generally be cautious. Cannabis, especially when smoked and with tobacco increases the heart rate, and that may be fatal in the worst cases. When there are undiagnosed, pre-existing medical conditions, this is not an avoidable risk.
Notwithstanding this risk is also present during other activities which may induce tachycardia/palpitations e.g. sex, sport, sauna visits, arguments, visit to Job Centres, bullying, dangerous situations in traffic, or perusing the Rheinzeitung concerning the topic of cannabis deaths.
When one observes enough people over a sufficiently long period of time, somebody will die e.g. one death during the Berlin Marathon is normal.
As a result the following statement by Hartung is meaningless: “The problem is that we cannot estimate who will suffer from cardiac arrhythmia (irregular heartbeat). We can nevertheless assume that theoretically it could affect every cannabis user even when they have already smoked weed without developing symptoms.”
In Hartungs’s statements it is perceptible that he urgently wanted to find something during his investigation, so as to counteract a supposed playing down of (the dangers) of cannabis: “Until now it was often assumed that cannabis could not cause damage.” He went on that cannabis is generally regarded as a drug with “euphoric affects without adverse reactions.”
In his article he criticised, “”little public awareness of the potentially hazardous cardiovascular effects associated with the consumption of cannabis” – in view of the relative risk, this would however be appropriate.
Dr Grotenhermen explains about the extent of the risk in comparison to other substances, ,”If one could say about each medication after one has used it for decades, ’we have now identified the first two cases of death,’ then actually one would be completely enthusiastic,” the expert declares. “They will hardly find that for any pharmaceuticals.”
4. Political impact
In political terms this study is grist to the mill of the “cannabis is dangerous” faction. As with the “weed makes people stupid” study, only the first headline will linger in their memory as it will with the general public, whereas each critique however well founded will seldom be printed let alone taken notice of. Therewith Hartung has contributed to muddying the waters of the debate – possibly wilfully but certainly through negligence. Concerning Hartung’s motivation we can only speculate.
Perhaps it was scientific curiosity plain and simple. But the scientists could assume – on the basis too of their colleagues’ experiences when concerning themselves with similar cases – how much media resonance their hypotheses would bring about. As a result, the desire to make a big impact in the public mind, might be possible motivation. The affect on political debate and their own location is clear. In this context I would like to draw attention to the article ‘Von Hanf ist die Rede – Anmerkungen zum wissenschaftlichen und politischen Diskussionsstand in Deutschland’ (Hemp is the Topic – Comments on the State of the Scientific and Political Discourse in Germany)in which is delineated how some researchers in the past raised their profile with large “Cannabis is dangerous” studies, and with them appointed themselves Crown witnesses for Prohibition.
To the dynamics of media in such media see: So kommen Meldungen wie “Cannabis macht dumm” zustande (This is how reports come about like ‘Cannabis makes people stupid’ ).