In patients with fibromyalgia, the central nervous system is inflamed, as is the rest of the body, according to a study that found a large range of increased inflammatory factors in the blood and spinal fluid of fibromyalgia patients.

But the study could not demonstrate if the increased inflammation causes, or is a risk factor for, pain in fibromyalgia — or if it’s a consequence thereof. In addition, other disease-related factors such as inactivity, depression, poor sleep or pain-related stress have all been linked to increased low-grade inflammation.

The study, “Evidence of both systemic inflammation and neuroinflammation in fibromyalgia patients, as assessed by a multiplex protein panel applied to the cerebrospinal fluid and to plasma,” appeared in the Journal of Pain Research.

Plenty of research has shown that fibromyalgia patients seem to have what researchers call central sensitization — a condition in which nerve connections in the spinal cord and brain get overly sensitive to stimuli, also reacting with pain when there is no real pain-causing event.

But studies of chronic pain also show that inflammation often accompanies other molecular changes. Earlier attempts to analyze inflammatory factors in fibromyalgia exist, but most studies have looked at a few factors at a time, which only gives researchers a limited view of what is going on.

To overcome this, Swedish researchers at Linköping University and Uppsala University gathered 40 fibromyalgia patients to perform a large-scale analysis of 92 inflammatory factors simultaneously. Researchers took blood and cerebrospinal fluid samples from the patients, as well as from healthy controls. The screening revealed increased levels of inflammation markers in patients’ blood plasma and cerebrospinal fluid. The profiles of inflammatory markers were distinctly different in patients and controls, and also differed between blood and spinal fluid.

Although the findings suggest that fibromyalgia patients have an ongoing inflammation that affects both the body and the brain and spinal cord, researchers underscored that many factors that could have influenced the result.

For instance, body weight can affect inflammatory signaling, and the team did not have access to participants’ body mass index measurements. In addition, measuring inflammatory factors is fraught with technical difficulties, as the initial handling of samples has an effect on making correct measurements. In the study, patient and control samples came from different sources, introducing a potential bias.

Also, a comparison between patients and controls reveal nothing about how inflammatory changes relate to the disease.

“Whether our findings are a risk factor for, a direct mirror of, or a consequence of the pathophysiological [disease mechanism] processes involved in these patients is hence an important area for further investigations,” wrote researchers, who suggested more studies to better understand the inflammatory processes present in fibromyalgia.