Physical issues often cause severe pain, but emotional and social factors can affect how we feel and respond to it. “Pain usually has physical and psychosocial parts,” said Noemi Gozzi, a doctoral student at ETH Zurich.
Doctors try to consider both aspects when treating pain, but it’s hard to separate them. They usually rely on patients’ descriptions to assess pain, which can lead to broad treatments. Opioid painkillers are still commonly used despite their drawbacks, such as side effects, reduced effectiveness over time, and the risk of addiction or overdose.
Stanisa Raspopovic’s group at ETH Zurich, including Gozzi, has worked with Balgrist University Hospital to create a method to separate and measure pain’s physical and emotional parts.
Raspopovic, recently a professor of neuroengineering at ETH Zurich, explained that their method can help doctors assess pain more individually, leading to personalized treatment.
If the pain is mainly physical, doctors may focus on medication or physiotherapy. If emotional factors are more significant, psychological support might be recommended to help change how the pain is perceived.
To develop the new method, researchers studied data from 118 people, including those with chronic pain and healthy individuals. They asked detailed questions about the participants’ pain perception, mental health factors like depression and anxiety, and how often pain prevented them from working. They also looked at how well the participants could distract themselves from pain, whether pain made them feel helpless, or if they tended to overestimate their pain.
The researchers used standardized tests to compare how participants felt pain. They applied small, safe, painful heat pulses to the skin. They measured the brain’s response with an EEG and the skin’s electrical conductivity, which changes with sweating and helps measure stress, pain, and emotions. They also included participants’ diagnoses from Balgrist University Hospital.
Using machine learning, the researchers analyzed the data to separate pain’s physical and emotional parts. They created two new indices: one for the physical causes of pain and another for how much emotional factors increase it. These indices help doctors better understand and treat a patient’s pain.
The researchers continue their study with other hospitals to test the new method’s effectiveness in real-world settings.
Journal reference:
- Noemi Gozzi, Greta Preatoni, et al., Unraveling pain’s physiological and psychosocial signatures by machine learning. Med. DOI:10.1016/j.medj.2024.07.016.