Where is the field of pain going? Reflections on the last EFIC congress.
The last congress of the European Pain Federation took place last September in beautiful Valencia (Spain). Big congresses typically have so many lectures and sessions, often in parallel, that everybody is sort of living a different and personal experience – a bit like visiting one same region of the world, but planning the journey differently, taking different paths. What follows here, it is therefore just my experience, but anyway, I hope it can be of interest.
The general feeling is that knowledge around pain is accumulating fast. Many smart people are working hard to do their part and unravel at least one piece of the puzzle. It also feels like that the puzzle has billion pieces and it might take a while for us to finish it. The hope is that, as Douglas Adams imagined in his Hitchhiker’s guide to the Galaxy,rats will eventually bring us to answer the ultimate question of life, the universe, and everything (hence pain included). And that (spoiler alert!)the answer is not 42. But I’m digressing. What I am trying to say is that all this knowledge needs to converge at some point, in order to deliver the best possible treatment to the single patient. From my perspective, two main lines of research are currently hot topics in the scientific community: biology and patient-centred care. The two are obviously interconnected, but let’s take them as two separate pieces of the puzzle.
Biology and pain
So, biology. It might well be that some people are significantly more vulnerable to pain. This might be because of genetic influences, epigenetic mechanisms, or, more likely, a combination of both (Polli et al. 2019). The fact is that – as Prof. Diatchenkoshowed – persistent pain syndromes are partially heritable and many genes have been associated to persistent pain. Intriguingly, such genes are not related to bones, muscles, or skin structures, but rather on the nervous and immune systems. In addition, this genetic heritability is substantially shared among different persistent pain conditions. This is important. Clinician and researchers strive for finding subgroups in order to better predict the natural history of the disease, or the effectiveness of their treatments. However, they mostly try to identify subgroups within a single pain condition. For instance, subgrouping people with fibromyalgia, or persistent low back pain. If the research on pain vulnerability is pointing in the right direction, it seems that we will be able to perhaps identify subgroups across different pain syndromes. And this would clearly have an influence on how we look at, diagnose, and treat people with persistent pain (Huijnen et al. 2015). Exciting times ahead!
A second hot topic in the field of biology and pain is represented by neuroinflammation, and in particular the role of glial cells. Up until 10-15 years ago, glial cellswere merely considered as neuron-supporting cells holding some immune functions. Now we fully appreciated their key role in actively contribute to establish or maintain nociceptive processes (Albrecht et al. 2019). Glial cells are basically at the cross-road between the immune and central nervous system and accumulating research shows that this interaction is of crucial importance – in fact, many people with persistent pain show some alteration of the immune system. This is a very exciting avenue in pain research so keep an eye on it.
After thinking about all this, however, one big question remains unanswered. How do we treat persistent pain? I mean, can science, biology or genetics help at all? We cannot do much (yet?) about genetic predisposition, and drugs targeting glial mechanisms are just not ready yet. Our best option at the moment is probably targeting one person’s lifestyle – sleep, stress, physical activity. Intriguingly, the underlying biological mechanisms that might explain why changing one’s lifestyle can influence nociceptive mechanisms are again related to glial cells, as Prof. Nijs showed (Nijs et al. 2017).
This also was, I think, a big part of the congress. To see so many people interested in putting the patient at the centre of the treatment is reassuring. Many clinicians and researchers highlighted the importance of the patient-clinician relationship, empathy, and education. A proper education is necessary to target patient’s expectations before proposing our treatments. Most patients with persistent pain expect exercise to increase their pain, for instance. In this context, we might consider education as a sort of primer for subsequent treatments within an operant conditioning model – as suggested by Prof. Meeus(Nijs et al. 2015).
Education is not merely the transfer of some information from the clinician to the patient. It is a complex, non-linear process in which the clinician tries to change some unhelpful thoughts, often in order to change patient’s lifestyle. Education can be powerful, and actually change one’s behaviour. However, it risks to be useless if the patient does not consider the information relevant to their condition, or does not understand what the clinician is talking about. Only those who actually show to have learnt and reconceptualised the meaning they give to their pain, recover and experience less pain, showed Prof. Moseley. And only those who believe that that information is relevant to them will want to learn it. Clinicians therefore need first to carefully assess what information is considered relevant by the patients, before going on and see if they have learnt and consolidated it. Learning seems a big variable in the outcome that has so far been overlooked. I guess future research will need to consider this.
After this first part of the treatment, other parts can be added. Exercise, for instance, or cognitive behavioural therapy. In this context, exercise could easily be seen not only as part of the treatment – which it clearly is – but also as sort of an assessment, where the clinician can get the idea on whether the patient has actually reconceptualised their pain. What a tough job!
EFIC organised a number of interviews – you can find them all on the EFIC Facebook page – with plenary speakers and other people that are or have been relevant to the study of pain. One of them is definitely Professor Stephen McMahon. One hallmark of my experience at EFIC was definitely being able to follow his interview. The interview was a real journey through his career, from his PhD in no less than Professor Patrick Wall’s lab to now. It is both a great overview on why we are where we are today, and an inspiring conversation with somebody with a very broad view on pain and research in general. Highly recommended! You can find the interview here.
Andrea Polli is a physiotherapist and OMT manual therapist. After his bachelor and master in rehabilitation of musculoskeletal disorders, he moved from Italy to the UK, to obtain the MSc in Pain: Science & Society at the prestigious King’s College London. He then returned to Italy for a few years, working at the IRCCS San Camillo Hospital, in Venice. He is part of the Pain in Motion group since 2015, where he works as PhD researcher at the Vrije Universiteit Brussel and KU Leuven, exploring whether epigenetic changes can play a role in helping people with persistent pain.
2019 Pain in Motion
Albrecht DS, Forsberg A, Sandström A, et al. Brain glial activation in fibromyalgia - A multi-site positron emission tomography investigation. Brain Behav Immun. 2019 Jan; 75:72-83.
Huijnen IP, Rusu AC, Scholich S, Meloto CB, Diatchenko L. Subgrouping of low back pain patients for targeting treatments: evidence from genetic, psychological, and activity-related behavioral approaches. Clin J Pain. 2015 Feb;31(2):123-32.
Nijs J, Loggia M, Polli A, et al. Sleep disturbances and severe stress as glial activators: key targets for treating central sensitization in chronic pain patients?Expert Opin Ther Targets. 2017 Aug;21(8):817-826.
Nijs J, Lluch Girbés E, Lundberg M, Malfliet A, Sterling M. Exercise therapy for chronic musculoskeletal pain: Innovation by altering pain memories.Man Ther. 2015 Feb;20(1):216-20.
Polli A, Nijs J, Ickmans K, Velkeniers B, Godderis L. Linking Lifestyle Factors to Complex Pain States: 3 Reasons Why Understanding Epigenetics May Improve the Delivery of Patient-Centered Care. Journal of Orthopaedic & Sports Physical Therapy, 2019; 49(10):683–687.