THURSDAY, Oct. 4, 2018 (HealthDay News) -- People with fibromyalgia have widespread inflammation in their brains, new research reveals.

"Finding an objective neurochemical change in the brains of people who are used to being told that their problems are imaginary is pretty important," explained senior study author Marco Loggia. He is associate director of the Center for Integrative Pain Neuroimaging at Harvard Medical School.

The new research used an advanced imaging test called positron emission tomography (PET) and looked at 31 people with fibromyalgia and 27 healthy "controls" from Boston and Stockholm, Sweden.

Dr. Harry Gewanter, a master of the American College of Rheumatology, agreed the findings could bring comfort to patients.

"There's a heck of a lot of stigma associated with chronic pain conditions like fibromyalgia. I think it's going to make a lot of people feel much better to know that there are physiologic changes you can find," Gewanter said.

Fibromyalgia causes pain throughout the body, according to the U.S. Centers for Disease Control and Prevention. The condition also causes sleep problems, fatigue and difficulty with thinking and memory.

The disorder affects about 4 million Americans, the CDC reports. The exact cause of fibromyalgia is unknown, though the researchers said it's likely a disease of the central nervous system. Medications and lifestyle modifications can help manage the condition.

All of the volunteers in the study underwent PET scans. Fibromyalgia patients in Boston were heavier than the healthy controls in Boston, and those in Stockholm with fibromyalgia. The researchers said this was the only significantly different variable between the two groups.

When the researchers compared the scans of people with fibromyalgia to healthy controls, they saw more inflammation in the immune cells of the brain (glia) in people with fibromyalgia.

Loggia said the findings might lead to better ways to test fibromyalgia treatments, to see if they reduce inflammation. It's also possible that this finding may eventually help researchers tease out the cause of the disorder.

Gewanter said this study gives scientists a number of possible directions to go. One is to be able to follow a treatment to see how well it works. Another is possibly developing ways to intervene with new treatments.

Now, treatment focuses on medication and lifestyle changes. According to the CDC, people with fibromyalgia are encouraged to try to exercise 30 minutes daily most days of the week. And establishing regular sleep habits can help, as can reducing stress as much as possible, perhaps using yoga or meditation.

The study was published recently in the journal Brain, Behavior, and Immunity.