Why Does 'Mono' Sometimes Turn Into Chronic Fatigue Syndrome?

WEDNESDAY, Jan. 27, 2021 (HealthDay News) -- While most people know about mononucleosis, the dreaded "kissing" disease that knocks down teenagers and young adults, many don't know there is a link between "mono" and chronic fatigue syndrome.

Now, new research that followed college students who didn't have mono yet (though some contracted it after the study began) sheds light on the risk factors that may trigger chronic fatigue syndrome for some people.

"A problem is, because there's so many different causes of ending up with this very debilitating illness, it's a little bit hard to understand what are some of the factors that might be predisposing or even precipitating the illness," said study author Leonard Jason, director of the Center for Community Research at DePaul University, in Chicago.

Mononucleosis is almost always caused by the Epstein-Barr virus, and most college students recover within one to six weeks, the researchers said. But mono isn't the only cause of what is also known as ME/CFS, which stands for myalgic encephalomyelitis/chronic fatigue syndrome.

For this study, researchers from DePaul University and Northwestern University focused on one particular trigger (mono) and a population that seems to get that trigger frequently (college students).

Of the 4,500 students, 238 (just over 5%) contracted mono. About 55 (23% of the students with mono) met the criteria for ME/CFS six months later, the study authors said. Twenty of them (8%) had severe ME/CFS.

The researchers discovered that people who developed ME/CFS had more physical symptoms and immune irregularities at baseline. The participants did not start with more psychological symptoms, such as stress, depression, anxiety or abnormal coping.

According to Dr. Lily Chu, vice president of the International Association for Chronic Fatigue Syndrome/Myalgic Encephalomyelitis, the misconception that ME/CFS is caused by psychological reasons has persisted for decades. This study adds to the evidence that ME/CFS is not a psychiatric or psychological condition, she said.

"This is a recurring issue, unfortunately, in medicine, where if there is an illness that we don't understand the cause of the illness, especially if it affects women, there is this presumption that the illness is related to the person's personality or to some psychiatric or psychological cause," Chu said.

Despite evidence to the contrary, it wasn't until 2017 that the U.S. Centers for Disease Control and Prevention removed cognitive behavioral therapy as first-line treatment for the disease, noted Chu, who was not involved with the new study.

That decades-long emphasis on cognitive behavioral therapy meant that promising areas of research were underfunded, Chu said, including immunological, neurological, infection-related and metabolic research. There are still no diagnostic tests or effective treatments for ME/CFS, she added.

"I think this study provides a great model for studying ME/CFS," Chu said. "And I would like to see prospective studies done on conditions other than just Epstein-Barr virus."

The research was published recently in the journal Clinical Infectious Diseases.

The CDC says that between 836,000 and 2.5 million people have ME/CFS, but 90% have not been diagnosed. Symptoms of ME/CFS include severe fatigue, poor sleep and cognitive impairment.

The research team is continuing to evaluate the patients, six years after the initial group joined the study. Deficiencies in certain proteins known as cytokines may suggested "predisposing irregularities in immune response," the researchers reported. They plan to analyze these cytokine networks in participants' blood.

This study may also help researchers studying COVID-19, Jason added. They can use that same database of 4,500 students to look for risk factors that indicate who might become what are called long-haulers, people whose symptoms linger.

"And you can see it's happening with COVID-19," Jason said, because over 25 million people in the United States have tested positive. "And if it turns out that 10% are basically long-haulers in some ways, we're talking about hundreds of thousands of people who are going to be ill. And if our model of ME/CFS is anything like what's occurring, this is a major issue" for the United States, he added.

More information

The U.S. Centers for Disease Control and Prevention has more on ME/CFS.

SOURCES: Leonard Jason, PhD, professor of psychology and director, Center for Community Research, DePaul University, Chicago; Lily Chu, MD, vice president, International Association for Chronic Fatigue Syndrome/Myalgic Encephalomyelitis; Clinical Infectious Diseases, Dec. 25, 2020