THURSDAY, April 27, 2017 (HealthDay News) -- Scientists have found differences in the gut bacteria of people with chronic fatigue syndrome versus their healthy peers.
The finding is among the first to link abnormalities in the makeup of gut bacteria -- the "microbiome" -- and chronic fatigue, a mysterious and debilitating malady.
Whether these differences are merely a sign of chronic fatigue syndrome or an underlying cause isn't clear, said study lead author Dr. W. Ian Lipkin.
But they could be tied to disease severity, said Lipkin. He is director of the Center for Infection and Immunity at Columbia University Mailman School of Public Health.
Chronic fatigue syndrome affects about 1 million Americans -- women more often than men, according to the U.S. Centers for Disease Control and Prevention.
People with the syndrome typically complain of extreme fatigue after exertion, muscle and joint pain, thinking difficulty and sleep problems. But only about 20 percent of people who have the syndrome actually know it, because it's difficult to diagnose, the CDC notes.
Scientists have begun to look to the microbiome for answers to a host of medical mysteries.
Your microbiome is the community of bacteria living on and in your body. "In this case, we are describing the bacteria in your intestines," said Lipkin.
"These bacteria influence how we feel, how our immune systems respond to our environment and our resistance to disease," he added.
To explore a potential association between chronic fatigue syndrome and an imbalance in the gut environment, researchers recruited 50 patients with chronic fatigue syndrome and 50 healthy peers from four U.S. cities. Most were women, average age 51.
Fecal samples from all participants were genetically broken down to identify the types and quantity of bacteria present. Blood samples were also analyzed.
What the investigation found is that people with chronic fatigue syndrome "have different bacteria in their intestines than healthier people," Lipkin said.
Specifically, the research team observed that chronic fatigue patients -- but not the healthy participants -- had high quantities of several intestinal bacteria species.
Also, among people with chronic fatigue syndrome, investigators found that bacterial composition appeared to shift depending on disease severity.
Both associations held up regardless of whether or not a person with chronic fatigue syndrome also had irritable bowel syndrome. The two often go hand-in-hand.
"This study is an early but important step toward determining the composition of a healthy microbiome," said Lipkin. Ultimately, the findings may aid diagnoses and point to new treatments targeting subtypes of chronic fatigue, he and his colleagues suggested.
"As the work continues," Lipkin added, "we anticipate that physicians will be able to make specific recommendations that influence the composition of our microbiomes, and reduce some symptoms of [chronic fatigue syndrome]."
Currently, there are no approved treatments for chronic fatigue syndrome in the United States.
However, one doctor cautioned that much more research is needed first.
There is unlikely to be a single explanation or "silver bullet" for the syndrome, said Dr. Jim Pagel. He is an associate clinical professor with the University of Colorado Medical School System.
Pagel noted that microbiome abnormalities might reflect just one "secondary" factor related to, but not causing, chronic fatigue syndrome. Numerous factors could be involved.
The bottom-line: "We have only a very limited understanding as to what makes up an appropriate diet and the associations of gastrointestinal flora with illness," said Pagel. "There is far more we don't know than what we do know."
The findings were published online April 26 in the journal Microbiome.
There's more on chronic fatigue syndrome at the U.S. National Institutes of Health.