Severe pain is often attributed to physical causes. However, emotional, psychological, and social factors can also impact how we experience and respond to pain. Noemi Gozzi, a doctoral student at ETH Zurich, explains that pain typically consists of both a physical and a psychosocial component.
Physicians strive to consider this when making treatment recommendations. However, distinguishing one component from the other has been challenging. Physicians often use straightforward methods to assess pain and its severity, relying on the patient’s subjective descriptions. This can result in nonspecific treatments. Despite their drawbacks such as adverse effects, reduced effectiveness over time, and the potential for addiction or overdose, opioid painkillers continue to be widely used.
Making treatment more individual
In recent years, Stanisa Raspopovic’s group at ETH Zurich, which includes Gozzi, has collaborated with researchers at Balgrist University Hospital in Zurich to create a new approach to effectively differentiate and measure the physical and psychosocial aspects of pain. They have published their new method in the current issue of the journal Med. Raspopovic was formerly a professor of Neuroengineering at ETH Zurich.
“Our new approach should help physicians assess patients’ pain more individually, allowing for more personalized treatment in the future,” Raspopovic states. If the pain is mainly physical, doctors are likely to focus treatment on the physical aspect, including the use of medications or physiotherapy. Alternatively, if psychosocial factors significantly contribute to the patient’s pain experience, it may be beneficial to address the perception of pain through psychological or psychotherapeutic support.
Large dataset
To develop the new method, the researchers analyzed data from 118 volunteers, including people with chronic pain as well as healthy controls. The researchers asked the study participants in detail about their perception of pain and any psychosocial characteristics such as depression, anxiety, and fatigue. They also inquired about the frequency with which the participants experienced pain that prevented them from going to work. Additionally, the researchers assessed the participant’s ability to distract themselves from pain and examined the extent to which pain led them to ruminate or feel helpless, causing them to overestimate the intensity of the pain.
The researchers used standardized measurements to compare the subjects’ perceptions of pain. Participants received small, non-dangerous but painful pulses of heat on their skin. To record the physical reaction to the pain, the researchers measured the study participants’ brain activity using an electroencephalogram (EEG) and the skin’s electrical conductivity, which changes depending on how much someone is sweating and is used to measure stress, pain, and emotional arousal. The extensive dataset also included the diagnoses of the study participants, which the researchers at Balgrist University Hospital made.
Machine learning delivers precision medicine.
Machine learning has assisted researchers in analyzing a large amount of data, enabling them to clearly distinguish between the two components of pain and develop a new index for each. The index for the physical component of pain indicates the extent to which physical processes cause the pain, while the index for the psychosocial component indicates how strongly emotional and psychological factors intensify the pain. Finally, the scientists validated these two factors using comprehensive measurement data from the participants.
The new method combines measuring body signals, self-disclosure, computerized evaluation, and the resulting two indices. It is intended to help physicians treat pain. “Our method enables physicians to precisely characterize the pain a particular person is suffering, so they can better decide what kind of targeted treatment is needed,” says Gozzi.