The benefits of harm reduction are not as obvious as they seem

Warning: This Area Contains Tobacco Smoke
Warning: This Area Contains Tobacco Smoke (Photo credit: tbone_sandwich)

Theodore Dalrymple points out the inconsistency in the British Medical Journal’s vigorous advocacy for harm reduction where heroin is concerned and its squeamishness with harm reduction for nicotine. He pulls a passage from BMJ and inserts comments:

What, then, does the BMJ, so much in favour of harm reduction for heroin addicts, say about harm reduction for smokers?

A broad perspective suggests potential problems [from a public health perspective].

Firstly, the new nicotine containing products are not intuitively appealing; smokers will need to be persuaded of their benefits. For public health there is a key benefit: it is easier to use them than to   quit. Here I interject that the same is true of the methadone or other substitute for heroin. But for most smokers quitting is the best option and should be presented as achievable and attractive.

   So rolling out harm reduction puts public health in the contradictory position of having to emphasise both the difficulties and attractions of quitting. Why should harm reduction for heroin addiction be any different, one might ask? A related danger is that children will pick up on this apparent confusion. While previous generations were told simply that tobacco is bad, new ones would learn that nicotine is acceptable – just be careful how you access it. This is precisely the burden of public health “education” with regard to heroin and other drug addiction. Moreover, promotion of harm reduction might reduce the perceived “cost” of uptake. Would not the same effect apply to the medical treatment of drug addiction, to say nothing of the provision of free needles? Finally, the fact that e-cigarettes deliberately mimic conventional ones (even to emitting fake smoke) may result in the inadvertent modelling of smoking. Would not the prescription of injectable methadone not do the same? More broadly, the media, which in the UK have become a reliable supporter of comprehensive control measures, might also struggle with this more complex position. How much media effort, one is inclined to ask, ‘reliably’ goes into supporting ‘comprehensive control measures’ with regard to illicit drugs? Thus the benefits of harm reduction are not as obvious as they seem.

The article goes on to criticise harm reduction in tobacco because of the obvious, if not entirely consistent, commercial interests that the tobacco and pharmaceutical industries have in it.

Dead space is the part of the syringe where fluid is retained once the plunger is fully depressed. High-dead-space syringes retain fluid both in the syringe itself and in the needle; low-dead-space syringes expel all the fluid in the syringe, retaining only a small amount of fluid. (In low-dead-space syringes, the needle is not detachable.)

In experiments that mimicked drug injections, the high-dead-space syringes retained 1,000 times as many microliters of blood, even after rinsing. For people carrying HIV with viral loads between one million copies and 2,000 copies per milliliter, the capacious syringes could carry multiple copies of HIV, “whereas,” William A. Zule and his coauthors write, “low-dead-space syringes would retain even a single copy only a fraction of the time.”

What’s interesting here, is that needle exchange advocates have been so busy arguing that they are the obvious answer to injection disease transmission on pragmatic and moral grounds, while insisting that there are no social costs (ignoring the fact that needle sharing persists among exchange users, discarded syringes are a problem, they often ignore treatment access problems and that they make convey despair to addicts and communities), that they seem to have never stopped to ask if we could make syringes safer.

These low-dead-space syringes in universal use might be much more effective than needle exchanges and prevent transmissions through accidental pokes. If so, will they follow the evidence?

Depression, exercise, research and the media

A recent study on treating depression with exercise encouragement and advice has caused quite a stir. Check out the headlines.

But the paper itself says the following:

The main implication of our results is that advice and encouragement to increase physical activity is not an effective strategy for reducing symptoms of depression. Although our intervention increased physical activity, the increase may not have been sufficiently large to influence depression outcomes.

An article tackling the coverage of the study quotes the pay-walled editorial from the same issue of the medical journal:

Or, as the BMJ’s own editorial points out: “Patients in both groups therefore already received high quality care, and 57% were taking antidepressants at recruitment. It may have been difficult for the addition of a physical activity intervention to make an appreciable difference.” Further, about 25 per cent were already meeting Government exercise guidelines, so there may have been “little room for the intervention to make a difference”. The BMJ says that there has still been insufficient research.

I think that this is a very important point. It would be interesting to compare the following groups:

  1. exercise/no medication
  2. exercise/medication
  3. no exercise/medication
  4. no exercise/no medication

Further, look at the effect of exercise rather than the effect of advice and support. AND, follow them for at least a year. Then, if we establish exercise is helpful, we can look at whether it helps some but not others, what dose and frequency is needed, whether it’s helpful as an adjunct to other treatments, and THEN explore strategies for getting patients to exercise.

Another blog summarizes the study this way:

So, what did the study actually find? Two groups of depressed individuals were kept on their standard treatment plan and one of those groups was mildly encouraged to do more exercise through a few short telephone calls and a couple of face to face meetings. There was no minimum amount of exercise required for inclusion in the study, nor were any facilities for exercise provided. Over half of the participants were on anti-depressant medication that may provide some of the benefits of exercise alone, thus negating the benefit of exercise on self reported happiness.

At the four month follow up, exactly the same number of people in the treatment group had participated in physical activity as had done so in the control group (though it should be noted that there were seventeen more people in the control group than in the treatment group). Over the course of the study there was only a fifteen percent difference in the amount of exercise between the two groups! This study shows that the current exercise based treatment plan of telling people to exercise is not effective. It does not assess the outcomes of enabling people to exercise, or indeed of actually exercising.

“EXERCISE DOES NOT HELP DEPRESSION” is a good headline, but it’s not that simple and it’s not true.