Conditioned placebo response and its application to global medicine
Benedetti is arguably the world expert on mechanisms of the placebo effect, with very few other people conducting research in the field. His recent paper 'Teaching neurons to respond to placebos' (2016) is just the latest of a vast body of work that seeks to define the exact mechanisms behind the placebo effect. His recent paper looked at patients with Parkinson’s disease, measuring their placebo response after various periods of conditioning. He found that receiving four injections of the active drug over four days, adequately conditioned patients to respond clinically and neuronally to a single placebo, as if it were the active drug. It was found that this effect lasted for over 24 hours, and with the administration of another placebo, it continued for another 24 hours. The study did not assess the duration of effects beyond 48 hours, but if the conditioned placebo response is limited to 48 hours, it still has great potential.
Further tests need to be done, to understand if a greater period of conditioning would lead to a more sustained placebo response. And whether alternating the conditioning and placebo periods over time leads to renewed effects. If this is the case, then active drugs could be given to patients for four days, with a two day placebo period, alleviating the pressure on drug supplies, by reducing their need. To best apply this to global medicine, it will also be necessary to explore this with patients with a range of other diseases, to see if it would continue to be applicable to diseases more common in LDCs.
Resolving ethical conflicts
As stated previously, there are several ethical considerations that would need to be resolved in order to introduce conditioned placebo response to treatment plans. These issues involve ensuring efficacy, ensuring just evaluation of treatment (WHO, 2015) and quantifying the benefit/loss ratio. Our most natural response to the possibility of giving placebo conditioning to LDCs is that we immediately feel it is immoral to do so. Jumping to concern for exploiting LDCs and introducing deception into global medicine. We feel that our developed countries should value people of LDCs equally and not provide them with any treatment less than what we would use ourselves. However, whilst these perspectives are certainly valid, they may not actually be relevant concerns.
Firstly, on the point of deception, various studies have shown that patients can be told that they are taking a placebo and that they will still experience response (Blease, 2016). This is particularly true of conditioned placebo response as it does not appear to require conscious anticipation to work. This has been demonstrated by several studies involving mice who receive medication in saccharine sweetened water. After the medication is removed, they continue to respond to the saccharine flavour as if it were the active medication (Ader, 1975). Therefore, deception does not necessarily need to be involved, although the best options still need to be tested regarding this and the efficacy of placebo in global medicine.
Currently research into the incorporation of placebo response into Primary Care in more economically developed countries is being undertaken at various locations in the UK (Southampton, Nottingham, Oxford). Therefore, exploring the incorporation of placebo into treatments in LDCs would not necessarily demonstrate that we might value their lives as less than our own. We do deem placebos an adequate tool to explore for our own treatment, so therefore if we hold similar standards for LDCs we should be able to explore the possibility of placebo treatments in global medicine too. However, it is important to consider that diseases common in LDCs are not as common in our own countries, and if we were to suffer from them similarly, we may not deem placebo treatments adequate. Therefore, we must ensure that the risks, benefits and cost is calculated as it would be in our own countries. In the UK, before a treatment is made available on the NHS, the treatment is evaluated against the current treatments available, the risks and benefits of the treatment to the patient and the financial cost (Parliamentary Office of Science & Technology, 2015). Whilst, putting financial value on human life or quality life is understandably uncomfortable, it is a necessary measure that is done around the world. As there is no ‘Global Health Service’, and such measures are controlled largely at a national level, the evaluation must be done in light of the situation within the countries the treatment is proposed for. So, when evaluating the placebo treatment against the current treatment available, it must be considered that for many people, there simply may not be any treatment available. For many, it could be placebo treatment or no treatment. The cost and associated risks of placebos are negligible as there are no active ingredients. Therefore, considering the treatment evaluation methods in more developed countries, providing that placebo treatments are more effective than no treatment, and that they do not harm the patient, they should be considered for use in global medicine where treatment access in particularly poor.