Drug testing – the decision is political
BY PROFESSOER STEPHEN LEEDER, EMERITUS PROFESSOR, PUBLIC HEALTH, UNIVERSITY OF SYDNEY
How can we help to prevent drug-related deaths of young people attending music festivals? One suggestion receiving media attention and polarising the debate is drug testing at the venues.
Three facts from medicine and public health should help the decision-makers. But many facts from chemistry, biochemistry and pharmacology also need consideration. That is not my domain.
Hope and the silver bullet
First, let’s accept that hope springs eternal: when confronted with a complicated problem we wish for a simple solution – a magic bullet. We forget that there are seldom simple solutions to complex social problems.
We see the occasional successes of ‘precision medicine’ where a single new medication dramatically alters the course of a disease; for example, the tyrosine kinase inhibitors in the management of patients carrying the phi chromosome who develop chronic myeloid leukaemia. In general, we pursue the one thing that will make a big difference – usually without finding it. Pill testing might be mistaken for such a silver bullet.
The messiness of reality
Second, we health professionals should accept that we usually manage complex medical and surgical problems incrementally – often muddling through. This can be quite effective, but it’s messier. A bit like evolution, which makes many mistakes – as any obstetrician would verify.
But we still pursue the silver bullets! Consider the energy and money supporting the search for risk factors for cardiovascular disease. Google ‘coronary heart disease risk factors’ and hundreds of scientific papers will full your screen. Beside the six principal ‘planet-sized’ factors, such as smoking, where political action has decreased the incidence of atheromatous heart disease, there are many other factors – ‘asteroids’ – where tiny associations have been demonstrated but nothing therapeutic has eventuated. Useless.
Living with ambiguity
Third, it is unlikely that one intervention alone will reduce or eliminate drug use in the socially, psychologically and chemically complex context of a young person’s musical festival. In public health, as in clinical practice, it is uncommon to find one therapeutic effort which kills a problem stone dead. You could argue that immunisation comes close; while the successes of immunisation programs are clear, it would be a mistake to reduce these programs to doctors turning up with needles or to oral vaccines. These programs are sophisticated organisational efforts, costing millions; but reflect, for a moment of humility, on how few diseases we have eradicated this way.
In 1993, my public health colleague, Simon Chapman, wrote a superb paper showing the dramatic decline in smoking rates over the past 20 or 30 years and asking if it could be due to one particular intervention.
One can readily do a randomised trial of a new medication for blood pressure, but not to show the effect of plain packaging of cigarettes on smoking rates. Chapman showed that smoking fell at a steady rate against a background of lots of actions – banning advertising, health promotion, taxing tobacco, changing community knowledge and attitudes, and more.
But none of these individual interventions changed the gradient of the downward-sloping line. Taken together, though, they were clearly associated. To determine the effect of any one of these interventions was, Chapman suggested, akin to trying to unravel gossamer with boxing gloves https://www.ncbi.nlm.nih.gov/pubmed/8374457
If pill testing were introduced, it would be impossible to attribute to it any reduction in deaths – from, say, one or two to none, or, for that matter, an increase of the same order – any more than we could measure the effectiveness of sniffer dogs and uniformed police. The numbers are too small and the evaluative methods do not extend to the microscopic level.
It might be argued that pill testing should be assessed in terms of adverse events, other than death, related to drug use. This would increase the sample size and make assessment of effect easier, but who defines an adverse event? To what extent does the enumeration of an adverse event depend upon available professionals able to make the diagnosis, and what would be the relevant post-event time-span? And remember, it is deaths we are seeking to prevent, not simply improving efficiency.
The decision to provide pill testing, is, therefore, political, not medical, nor scientific. It cannot be ducked by saying that there is, or is not, evidence on which to base a decision.
Prima facie, it sounds like a good idea. Those knowledgeable of the sociology and psychology of youth music festivals, and young people themselves, should offer their opinions. Assuming that they favour testing, that pill testing is technically accurate, and that the cost is reasonable, it should be tried. We should observe carefully for the inevitably unintended side-effects.
This is how we usually, and slowly, make progress in promoting and protecting the health of the public.
Published: 15 Feb 2019