Study finds unique “molecular signature” for fibromyalgia

Fibromyalgia can be reliably detected in blood samples, a discovery that will hopefully lead to faster diagnoses, according to a new study by researchers at Ohio State University and published in the Journal of Biological Chemistry.

The study included 50 people with a fibromyalgia diagnosis, 29 with rheumatoid arthritis, 19 who have osteoarthritis, and 23 with lupus. Researchers examined blood samples from each participant using vibrational spectroscopy, which measures the energy level of molecules within the sample. Scientists detected clear patterns that consistently set fibromyalgia patients' blood sample results apart from those with other, similar disorders, according to a statement by the university.

First, the researchers analyzed blood samples from participants whose disease status they knew, so they could develop a baseline pattern for each diagnosis. Then, using two types of spectroscopy, they evaluated the rest of the samples blindly, without knowing the participants' diagnoses, and accurately clustered every study participant into the appropriate disease category based on a molecular signature, researchers said.

The discovery could be an important turning point in care of patients with a disease that is frequently misdiagnosed or undiagnosed, leaving them without proper care and advice on managing their chronic pain and fatigue, according to lead researcher Kevin Hackshaw, PhD, an associate professor in Ohio State's College of Medicine and a rheumatologist at the university's Wexner Medical Center.

Identification of biomarkers of the disease, which researchers call a "metabolic fingerprint,” could also open up the possibility of targeted treatments, he said.

To diagnose fibromyalgia, doctors now rely on patient-reported information about a multitude of symptoms and a physical evaluation of a patient's pain, focusing on specific tender points, he said. But there's no blood test, no clear-cut, easy-to-use tool to provide a quick answer.

"We found clear, reproducible metabolic patterns in the blood of dozens of patients with fibromyalgia. This brings us much closer to a blood test than we have ever been," Hackshaw said.

Though fibromyalgia is currently incurable, and treatment is limited to exercise, education, and antidepressants, an accurate diagnosis has many benefits, Hackshaw said. Those include ruling out other diseases, confirming for patients that their symptoms are real and not imagined, and guiding doctors toward disease recognition and appropriate treatment. Many undiagnosed patients are prescribed opioids, he said.

Hackshaw said the next step is a larger-scale clinical trial to determine if the success they saw in this research can be replicated. He said his goal is to have a test ready for widespread use within five years.

In addition to identifying fibromyalgia, the researchers also found evidence that the metabolic fingerprinting technique has the potential to determine the severity of fibromyalgia in an individual patient.

"This could lead to better, more directed treatment for patients," Hackshaw said.