By triggering its opioid receptors, the brain is naturally hardwired to shut down or dampen physical discomfort.
But for those with pain from chronic conditions such as fibromyalgia, a continued reliance on that process can be overtaxing — and ultimately ineffective.
“It’s sort of like trying to run a marathon … for months and years,” says Daniel Harper, Ph.D.
This is an apt description of pain. A sensation easily tolerated for a few moments can become excruciating over months and years.
“If a person’s brain is constantly releasing endogenous opioids over a long period of time, the system gets worse and worse about being able to do that.”
Beyond a reduced capacity to self-regulate, such gradual dysfunction also hinders the brain’s ability to process and translate the effects of prescription opioids which, in a typical patient, could offer relief.
Harper co-authored a recent study examining how the brains of 18 adult females with fibromyalgia respond when subjected to experimental pain (in this case, varying levels of intensity applied to the left thumb).
Published in May in the journal Pain, it is the first research of its kind to evaluate a chronic pain population via a combination of positron emission tomography and functional magnetic resonance imaging (fMRI).
Using the technology to conduct blood oxygenation-level-dependent (BOLD) imaging and observe opioid receptors during the pain sequence, the research team found reduced binding ability of the opioid receptors, which could mean fewer receptor molecules present in the brains of fibromyalgia patients.
As hypothesized, such dysregulation affected the brain’s innate ability to relieve pain.
Says Andrew Schrepf, Ph.D., a research fellow at the U-M pain center and a co-author of the study: “We’ve been able to complete the picture — their brains are doing a fairly bad job controlling pain.”
Although the researchers focused exclusively on subjects with fibromyalgia, ties that also were probed in a 2007 U-M study, the takeaways could be applied to other types of chronic pain, they say.
All this underscores the value of a personalized approach.
Unlike the CDC, which is still hanging on to the outdated model of “standardized” medicine – especially with its absurd position on standard dosages of opioids.