A study by an international group of pain experts, led by a professor at the Vrije Universiteit Brussel (VUB), has shed new light on the cause of various forms of chronic pain.
According to these scientists, central sensitization, a type of hypersensitivity of the central nervous system, is more common than thought in people suffering from chronic pain. This would mean that many patients should be helped with precision medicine, an individual treatment tailored to their needs.
Chronic pain, one of the most common causes of disability worldwide, often puzzles doctors. Because often patients feel much more pain than can be explained based on the damage that is determined in their body. In other words, the patient suffers from an ‘exaggerated’ feeling of pain without a clear cause.
The new study on chronic pain is the result of a collaboration between seventeen pain experts, from thirteen universities from seven countries. Together they wrote a summary report on their research. The management of the project was in the hands of VUB professor Jo Nijs.
Central sensitization
According to the analysis of the international experts, central sensitization is in many cases the main culprit in chronic pain.
“In central sensitization, the nerve cells in the central nervous system – that’s the brain and spinal cord – are hypersensitive to stimuli,” explains Professor Nijs. “We have known for some time that this is happening, but only now has it become clear that central sensitization can explain pain in very different diseases.”
Specifically, central sensitization could be the cause of pain in fibromyalgia, osteoarthritis, and arthritis, tendon disorders, headaches, and back pain.
Certain pains after cancer, surgery, and whiplash would also often be caused by an overstimulated central nervous system.
Tailor-made treatments
These insights can have important consequences for the treatment of chronic pain patients. According to the researchers, precision medicine can eliminate a lot of suffering.
“Precision medicine means that we can accommodate patients in certain subgroups, with each subgroup receiving a different treatment tailored to the patient,” says Professor Nijs. “We can now consider patients with central sensitization as a large and distinct subgroup, and this has major implications for the treatment of chronic pain.”
With such an approach, doctors will first examine in detail the specific pain complaints of the patient, with the presence or absence of central sensitization guiding the implementation of the treatment plan.
Crucially, patients with central sensitization do not respond well to treatment aimed at joints, muscles, or other ‘local’ structures, such as surgery, manual therapy, or certain forms of medication. They benefit more from centrally acting drugs combined with other ways to reduce pain, such as exercise, stress management, and treatment of any sleep problems. With a personalized approach, the quality of life of patients could be greatly improved.
