Aidan Cashin, PhD, is a NHMRC Emerging Leadership Fellow at the Centre for Pain IMPACT (Neuroscience Research Australia) and an Associate Lecturer at the School of Health Sciences, The University of New South Wales. His PhD research focused on improving the evidence-based management of low back pain. Cashin was recently announced as the Australian Pain Society’s Rising Star for 2023, an award showcasing up-and-coming researchers. As the Rising Star Award winner, Cashin will deliver a plenary lecture focusing on understanding the mechanisms of interventions to improve efficacy and clinical translation at the upcoming 43rd Annual Scientific Meeting (ASM) of the Australian Pain Society, which will be held in Canberra from April 2-5, 2023.
As part of the build-up for the ASM, Cashin spoke with Lincoln Tracy, a researcher and writer from Melbourne, Australia, about his passion for unpacking the mechanisms underlying treatments for chronic pain, what winning the Rising Star Award means to him, and his love of surfing. Below is an edited transcript of their conversation.
Before you pursued a career in pain research, you were an accredited exercise physiologist. What initially drew you to that line of work?
I’ve always had interest in health and a desire to try and help people in some way. And like a lot of 17- or 18-year-old kids, I liked the idea of medicine. But at the time, I wasn’t keen on spending so much time at university – I didn’t think I could handle it. Little did I know that I was probably going to spend that long at university anyway! But I found out about exercise physiology at an open day for the University of New South Wales. It sounded like it was going to tick all the boxes for me: I was really interested in the person-centred focus of the profession and the ability to meet people from all different walks of life.
And I loved it. It was rewarding but challenging at times, particularly the breadth of conditions people would present with. We saw people with complex regional pain syndrome, people with post-stroke pain, people with pain post-amputation… it was quite interesting. I enjoyed working with people who had pain because you got an opportunity to learn their story and their experiences to understand what was contributing to their pain and to try and help them shape their journey moving forward. In some clinics you’re quite restricted with your consultations, but the practice I worked at really made time for it.
How did you transition from working clinically to a career in research?
As an undergraduate exercise physiology student, I just thought research was all lab coats and pipetting. It just didn’t excite me. But John Booth, my clinical mentor at the time, really inspired and encouraged me to add research to my tool belt. John himself was a part-time clinician and academic – it seemed like a good combination and something I wanted to do. When he introduced me to James McAuley, we got on well and found our interests aligned. The rest, as they say, history. James became my PhD supervisor and showed me how patient-oriented research can be, and how patients can be involved on a day-to-day basis. That really caught my attention. I took to it and have never looked back.
Many clinicians make the shift into research after noticing something that affects their clinical work and wondering, ‘how can we do this better?’ Did you have a moment like that in your career?
Definitely. As an exercise physiologist, some of the primary tools we use on a daily basis are exercise- or movement-based strategies, as well as conversations around education and behavioural change. The exercise aspect really struck me, because at one point I noticed that regardless of whether I was providing a resistance-based program with weights or a more aerobic focused program, people seemed to be getting better. That started me wondering whether there was a specific part of what I was doing that was making a difference, or whether it was a more general effect of just doing something. That really interested both James and I – we had a common interest in wanting to unpack the effects of these interventions and the mechanisms underlying them.
You’ve done a lot of work around reporting on, and guidelines for, mediation analyses. What are mediation analyses, and why is it important to do these in a structured way?
Mediation analysis is an approach to understand how interventions, such as exercise, cause their effects on patient outcomes. It’s a complimentary approach to what trials or observational studies, which are good at telling you if and by how much something changes – but not how they change. Being able to look under the hood would have really helped back when I was a clinician, I could have really pulled apart an exercise to figure out it works by changing not only strength, but someone’s mastery of the experience or their confidence to move.
But through my research and trying to synthesise other studies which used mediation analysis, we found they were really poorly reported. This made it hard for us to use their findings in our research or to help inform clinical practice. Therefore, the focus of the AGReMA guidelines, authored by my colleague Hopin Lee, was to address this shortcoming we were seeing. We wanted to create a guideline that had a minimum set of recommendations so that anyone could report the results of a mediation analysis in a transparent way that included all the important and relevant details.
What does winning the Australian Pain Society Rising Star Award mean to you?
It’s a huge honour to receive this award. I’m a big fan of the Australian Pain Society and everything they do to help Australians living with pain. So, to be recognised by this group is great. I feel such a privilege to stand amongst the previous winners, who are all amazing researchers. In addition, no research is done on its own or in a vacuum. This award reflects all the support and achievements of the people around me – my supervisors, mentors, and collaborators – because without them I wouldn’t have been in the position to apply and be successful in this award. I’d like to give a particular shout-out to last year’s winner, Adrian Traeger, who was another of my PhD supervisors and has taught me so much.
Last year you also won the International Association for the Study of Pain’s Ronald Dubner Research Prize. Given your success, do you have any advice for anyone out there thinking of applying for awards like these?
I think the best advice I was given is that you have to be in it to win it. And while that bit of advice doesn’t guarantee success, it puts you in the mindset of getting out there and having a go. In my experience, putting yourself out there – and the unsuccessful applications that come with it – teaches you something every time you do it. Your ideas and thoughts get more clarity, or you get better at trying to describe your work, achievements, and impact. It’s not easy to do, but practicing is a useful exercise.
The other useful bit of advice is to read successful applications if you can. I feel that through reading other applications, you can see where you set yourself apart and how you are different. In some of the bigger schemes, like the NHMRC, reviewers are reading stacks of fantastic applications, so you need to find a way to make yourself unique and memorable. For me, I feel my uniqueness came about because I approached my PhD like an internship. I leant a lot of different skills, be that research methods or statistical approaches, and through that I could show impact across a broad range of areas rather than staying focused on just one area. But who knows?
Without giving too much away, what do you hope attendees will take away from your plenary lecture at the ASM later this year?
I hope attendees gain an appreciation for the role of mediation analysis alongside trials and observational studies, particularly if you’re trying to unpack how treatments work – whether they end up being effective or not. To me, this information isn’t just useful for researchers when they’re thinking about developing and optimising interventions. It’s also helpful for clinicians in how they implement these interventions in clinical practice, as they often think intuitively, rather than explicitly, about the mechanisms that are involved. The results of mediation analyses can really inform their decision-making.
For example, knowing how to provide an educational intervention that leads to larger changes in disability could help the clinician design their curriculum in a targeted way to optimise those mechanisms. I’ve found that targeting self-efficacy and someone’s ability to engage in physical activity despite being in pain is a key target for educational concepts. Knowing that, I can think about how I can give that person the relevant learning experiences to allow them to master the concepts or objectives before I even see them.
You’ve been involved in a diverse range of research activities throughout your PhD and your career thus far; is there a specific manuscript or project that you are most proud of?
I’ve always been proud of the work that I do, but if I had to pick one, I’d say I’m quite proud of the RESOLVE trial we had published in JAMA last year, where Matthew Bagg was the first author. I’m particularly proud of this one because I worked on this trial as a clinician during my PhD and made significant contributions to writing the final manuscript. It was a long time in the making – from designing the intervention all the way through to implementing it and then trying to make sense of it – but it was a fabulous project that is only getting started.
Our end goal is for graded sensorimotor retraining to be an intervention that’s available for clinicians to provide to patients in their practice. There are a few steps we have to go through to get there, such as comparing the intervention against guideline-based care rather than a placebo, but we’re looking for partners and developing grants to try and make that happen.
I’m sure everyone will be watching on with great interest! Changing tack now – if you had an unlimited amount of money to fund your dream research project, what question would you want to answer?
For most of my career I’ve been focused on trying to help people with back pain, particularly long-term back pain. One of the big roadblocks we seem to be facing as a field is trying to identify and develop effective treatments. This is a challenge, because we don’t understand what causes back pain or what causes it to persist. So, If I had all the necessary resources and participants willing to be involved, I would try to understand what causes back pain and determine whether terms like “nonspecific low back pain” are appropriate. If we know what causes pain, and then causes it to persist, we can develop targeted treatments to hopefully reduce the burden of – or even cure back pain.
I don’t have a particular theory as to what causes low back pain. But there are some smart people out there with some great ideas. Like Ben Wand, from The University of Notre Dame, who has developed a framework around how he things back pain persists. We recently wrote an article together about the Fit-for-Purpose physical therapy model, which explains how information from our environment and our body can lead to the development of persistent pain, while also providing opportunities to change it.
Finally, do you have any interesting hobbies or secret talents?
I don’t know if it’s a secret, but I try to surf as much as I can. My dad taught me when I was young, and I was just hooked. I competed when I was younger and was the Australian university national longboard champion at one point, which was a quite fun. Now my wife – who is a competitive longboard surfer – and I are teaching our son. He’s only 15 months old and although he doesn’t know it yet, he’s going to be hooked too [laughs].
Lincoln Tracy is a postdoctoral research fellow at Monash University and freelance writer from Melbourne, Australia. He is a member of the Australian Pain Society and enthusiastic conference attendee. You can follow him on Twitter (@lincolntracy) or check out some of his other writing on his website.