What causes chronic pain?
"Pain can become a chronic state if we're not going to receive help and we continue to do more damage."
Doctors are finding that patients with chronic pain are often dealing with a combination of biomechanical, psychological, biological, social and genetic factors. The growing body of research in this area is presenting new treatment opportunities for the future.
They found that during times of distress, such as during disease or accident, the pituitary gland secrete a flood of hormones that activates the HPA axis, which then produces painkillers.
Based on previous research, Stanford scientists predicted that after an injury, our bodies would ramp up our need for painkillers, and the HPA axis would then release adrenaline and cortisol, two hormones that suppress pain.
A professor of neurology at Stanford University and a co-author of the study said "We think chronic pain is this evolved, ancient mechanism that's saying we have an injury and we should defend ourselves" published in the journal Nature.
The researchers studied mice with an injury that caused inflammation in their Achilles tendons and then conducted genetic and molecular studies on their cells to see what happened in the absence of painkillers and when they were injected with cortisol.
When mice with the injury were given no painkiller, the adrenal glands released adrenaline and cortisol, while those who were given painkiller also had a spike in the hormones, but it wasn't until they were exposed to the hormones that they had trouble in navigating mazes, essentially because they weren't used to them.
There is also evidence that the pain signal can persist for many months after an injury, even though people may recover. For example, studies have shown that the average duration of persistent abdominal pain in people who have had appendectomies is more than two months.
Pain can often have a big impact on a person's life and can impact their job and relationships.
Sometimes, doctors may be required to try other treatment methods before starting pain treatment. If other treatments are not effective, there is usually a risk of the patient developing a resistant form of the condition. Chronic pain treatment involves the prescription of medication or treatment that relieves pain and prevents it from occurring.