A $7.5 million grant from the National Institute of Health will help University of Michigan Health System researchers determine the causes of chronic pain disorders.
Though the common cause of chronic pain is damage or inflammation in a joint or nerve, University researchers believe that for many sufferers, the chronic pain is actually occurring because the volume control was set too high in the brain for pain processing. The principal researchers on the project refer to this as “brain pain,” because it results from the brain instead of the localized damaged body part.
Because people experiencing this type of pain don’t respond well to current drug and non-drug treatments available for chronic pain, researchers said they're aiming to figure out whether these patients will respond better to treatments aimed at the brain instead.
The funding will specifically support the University’s Fibromyalgia Center of Research Translation and expand upon existing research on chronic pain disorders.
The research will be led by Daniel Clauw, director of the University’s Chronic Pain and Fatigue Research Center, and Chad Brummett, the director of the Department of Anesthesiology’s Division of Pain Research.
Clauw and Brummett plan to use brain imaging and functional MRIs, which measure brain activity by picking up on changes in blood flow, to study people with rheumatoid arthritis, osteoarthritis and carpal tunnel syndrome, in addition to fibromyalgia patients.
Clauw, a rheumatologist and researcher at the University, has been researching pain management for nearly three decades, and said he already has substantial evidence that suggests the secret to healing chronic pain lies in the brain.
“Our group and others have been talking about this for 10 or 20 years, and we now finally have the tools,” Clauw said. “The field has matured enough and the research tools are good enough that we can see by putting people in a brain scanner what their volume control is and test this hypothesis.”
Part of the research will involve studying people with rheumatoid arthritis that have recently begun a biological anti-inflammatory medication. Rheumatoid arthritis is an autoimmune disorder that causes inflammation of joint linings. The study will investigate the subset of people that still experience pain once all their inflammation has been treated.
“If we can identify in advance whose pain is coming from the brain and whose pain is coming from the hip, we wouldn’t do hip replacement surgery on these people, and we would instead use the drug and non-drug treatments we use to treat fibromyalgia,” Clauw said.
The research may also have implications on opioid prescriptions for pain disorders. Pain coming from the brain is inherently unresponsive to opioids and, according to Clauw, may even make brain pain conditions worse.
Though Clauw and Brummett are the study’s co-principal investigators, they plan to work with a broader pain research community.
“We are buoyed by a large number of really talented, incredible co-investigators and collaborators from both here at Michigan in the Department of Anesthesiology and outside the department, and even outside the University,” Brummett said.
Many University students will also be involved, whether through UROP projects, graduate work or other programs.
The grant is to be spread out over the next five years, giving Clauw, Brummett and their team time to recruit enough people with chronic pain conditions and do the brain imaging studies that will either confirm, refute or modify their hypothesis.
“But we have a fair amount of evidence already,” Clauw said. “In order to get NIH funding, you have to be halfway sure that what you think is going on is really going on.”
Brummett said he is hopeful that this research could change the way pain conditions are viewed by doctors.
“I think this can have a substantial impact on how we think of pain and how we treat pain,” Brummett said. “If we can do a better job of differentiating those patients who have pain of more peripheral nature versus those patients that might have pain from the central nervous system, I think we can better tailor treatment.”