Summary: One of the new studies using brain scans in whiplash injury patients found that individuals experiencing greater anxiety post-injury show greater crosstalk between the hippocampus and cortex, resulting in consolidation of injury memory. Such individuals are more likely to develop chronic pain.
Chronic pain is the most common health issue in the US, with about one-fourth of adults complaining about it. Chronic pain is pain that lasts for three months or more. It is a pain that outlasts the condition that initially caused that pain.
There are numerous reasons why chronic pain is so challenging to manage. As one can understand, it is a pain that outlasts the condition that initially caused it. This means that many individuals complaining about chronic pain are relatively healthy adults with normal lab tests. Even if they have some health condition that is often unrelated to their pain.
Since doctors are unable to say why the pain is happening, they also find it challenging to cure this pain. Of course, doctors use various treatments to manage such pain, both pharmacological and non-pharmacological therapies.
However, wouldn’t it be great if we could predict the risk of chronic pain after injury?
Many people continue to complain about pain for months and even years after making a complete recovery from an injury. However, this does not occur in all individuals, only in some. Which also means that these individuals might be different from others. There must be reason why chronic pain is more likely to occur in some. If science could understand why pain becomes chronic in some or who is at the greater risk, it could find ways of preventing chronic pain.
This is exactly what one of the new studies does. It found one of the reliable ways of identifying individuals who are at a greater risk of developing chronic pain.
This new study identified a way of understanding the risk of chronic pain within a few days of an injury. The results of this study were published in Nature Mental Health.
Since chronic pain often outlasts physical injury that initially caused it, researchers believe that, in many instances, the condition is due to certain brain changes or negative emotional learning.
Studies also show that people with specific personality traits are more likely to develop chronic pain. Thus, individuals who experience more anxiety post-trauma are also individuals who are more likely to experience chronic pain.
However, in the study, researchers wanted to identify a more objective way of determining the risk. Therefore, they scanned the brains of 110 patients (within the first three days of injury) who had experienced whiplash injuries. They noticed that those who experienced chronic pain had stronger crosstalk between the hippocampus and cortex.
The cortex is known to store long-term memories, whereas the hippocampus has a significant role in starting this storage process. Moreover, in their studies, they also saw increased anxiety or emotional response in these patients, with greater activity in the amygdala region.
So, researchers found that those who had greater anxiety during these early days were more likely to undergo specific brain changes leading to chronic pain.
This also means that the first few days are important to prevent these brain changes. Researchers say that during these early days, there must be a special focus on preventing anxiety in patients, and this may help prevent pain from becoming chronic.
There could be many ways of managing anxiety in those early days. This could be by using medications or even through non-pharmacological means. It is important to prevent this increased crosstalk between the hippocampus and the cortex, thus preventing pain consolidation.
In many cases of chronic pain, the brain plays an important role. Unlike in acute pain, the brain has a much greater role in chronic pain. It is the brain that decides if certain kinds of motions would be painful or not. Hence, during those early days, the focus must be both on managing injury and associated pain, along with the anxiety associated with that injury.
Source:
Branco, P., Bosak, N., Vigotsky, A. D., Granovsky, Y., Yarnitsky, D., & Apkarian, A. V. (2024). Hippocampal functional connectivity after whiplash injury is linked to the development of chronic pain. Nature Mental Health, 2(11), 1362–1370. https://doi.org/10.1038/s44220-024-00329-8
