Research into the best possible pain expectations: ‘Pain is inherently subjective’
Expectations influence our experience of pain. According to psychologist Dr Kaya J. Peerdeman, this is a key factor in pain care. For example, the expectation that taking a medication will reduce pain can lead to genuine pain relief (placebo effect), while the expectation of severe side effects or worsening of symptoms can actually have negative effects on the pain experience. How can we better respond to this in our patient care?
Kaya Peerdeman received a project grant from the Den Dulk-Moermans Fund – a named fund from the Leiden University Fund – to research ideal pain expectations. We spoke to her about her project.
How does the expectation of pain affect our experience of it?
Pain is inherently subjective. The experience of it depends on factors like the social context, individual thoughts and emotions. ‘Pain’ does not actually happen in your body. If you stub your toe while you’re dancing, it’s no big deal: the pain will be gone in a minute – if you notice it at all. But if you’re already cranky and tired that day and suddenly you stub your toe, you experience it completely differently. You might even hop around the house swearing!
It appears that expectations play a significant role in our experience of pain. The consensus is that it’s a self-fulfilling prophecy: if you expect something to hurt, it often does. Positive expectations have positive effects and negative expectations have negative effects. But I wondered whether this is not too simplistic a view. That’s why I’m investigating the conditions that lead to the best possible pain expectation.
When you have a medical procedure, an injection or an operation, you know it will be painful. The doctors know it too. What should they say to a patient in this situation? Should they say it will hurt, or is it better not to? Or might it be wise to exaggerate the pain so ultimately it’s not so bad? Theoretical and practice-driven experimental research can help shed light on this.
‘It appears that expectations play a significant role in our experience of pain’
You write that optimising expectations can significantly improve pain care. How does that work?
There are still many opportunities for healthcare providers to help people in the best possible way. I really want to find the best way to communicate to patients about pain. Realistic expectations are important. You have to be careful not to embellish or lie about the experience. An earlier study showed that if the researcher said ‘this won’t hurt’ before a very painful procedure, the participant no longer trusted the researcher afterwards. That’s very damaging. How would you be able to listen to the same person next time? Do you still trust a doctor who minimised your pain so much? Or even worse, does such an experience also create distrust of other doctors?
As part of the research we are now doing in the lab with the aid of the LUF grant, we are giving healthy people electrodes to wear on their arm. We then use a current to briefly cause them a controlled amount of pain, for one second each time. Before this pain stimulus, a screen shows them how much pain to expect: no pain, moderate pain or extreme pain. In most cases, the screen accurately indicates how much pain will occur, but sometimes it under- or overestimates it. This shows us how people react: how their experience of pain and their emotional experience are influenced by their expectations.
Another question is how exactly we can know how much pain someone will experience, since pain is subjective and influenced by many factors. Is it not more realistic to give broader estimates? How does this affect the experience of pain? I will also investigate that in the lab.
As humans we want to be in control, but unfortunately, we don’t always succeed. You can never have full control over experiences of pain and all the sensations surrounding them. But you can have some influence on the overall experience. And as healthcare providers, we need to use that to help patients.
Why is this such an interesting subject for you personally?
I’ve always been interested in people: what they do and why they do it. That’s why I studied psychology in Amsterdam. Pain is the most common physical symptom that people suffer; it’s very common. Chronic pain in particular has an enormous impact on our lives. We already know a lot about pain and treatments, but it’s not enough. After studying clinical psychology and doing research in that field, I started my PhD with a focus on pain and other physical symptoms. I was particularly interested in the mechanisms of placebo effects because of their relevance to the treatment of physical symptoms. This grew into research into the mechanisms and clinical implications of expectations around pain and other symptoms in the hope of improving treatments.
‘Chronic pain in particular has an enormous impact on our lives’
And now you’ve received a grant. What does that mean for your project?
Thanks to the LUF grant, we have just started collecting data. We want to do two experiments, and we are now working with participants in the lab. The second experiment will start later in 2022, and then we can run the analyses. There is quite a lot involved in terms of programming the project! I expect the real end result somewhere around September.
I would not have been able to do these studies without this grant. It made it possible for me to hire a research assistant, Suzanne Derksen. She is incredibly good at helping me with the research. Working together, you get a lot more done and come up with more and better ideas and insights, which is very valuable.
I also like that the grant provides us space to test and experiment with ideas at an early stage, so we can see what is relevant. This will let me take bigger steps and achieve more in the future. I hope this grant is a stepping stone to bigger research funded by bigger grants. I would like to do research with pain patients, to translate everything we think we’re going to find now into practice. I think this is incredibly valuable research, looking at the complexity of expectations.
Dr Peerdeman’s research is made possible by donations to the Leiden University Fund. Would you like to contribute to important scientific research? You can do so by setting up a named fund or contributing to an existing fund. For more information, please contact Heiltje Boumeester at h.boumeester@LUF.leidenuniv.nl at 071 527 5539.