Jan. 5, 2009 -- Experiencing serious trauma during childhood may increase a person's risk for developing chronic fatigue syndrome later in life, a new study suggests.
In the study from the CDC and Atlanta's Emory University, patients with chronic fatigue syndrome (CFS) reported much higher levels of childhood trauma than people without the disorder.
Severe childhood trauma -- including sexual abuse, emotional abuse, and neglect -- was associated with a sixfold increase in CFS.
Chronic fatigue syndrome remains a poorly understood disorder, and the suggestion that early-life stresses play an important role in the disease remains controversial.
Harvard Medical School professor and CFS expert Anthony L. Komaroff, FACP, did not take part in the new study. But he tells WebMD that the findings make a strong case for childhood trauma altering brain chemistry in a way that makes some people more vulnerable to CFS.
"These researchers are definitely not saying that early-life trauma is the cause of chronic fatigue syndrome," he says. "To say that something is a risk factor is very different from saying that it is the cause."
Childhood Trauma and CFS
The newly reported study builds on previous research from the CDC and Emory team, which first suggested the link between early-life trauma and an increased risk for CFS.
CDC estimates suggest that as many as 2.5% of American adults have CFS, even though many have not been diagnosed.
In that study, researchers examined and interviewed 43 CFS patients and 60 people without the disorder living in Wichita, Kan.
Self-reported childhood trauma was associated with a three- to eightfold increased risk for CFS, with the highest risk seen in patients who had suffered from more than one early-life trauma.
The new study involved 113 CFS patients and 124 people without the disorder living in urban, suburban, or rural Georgia.
In addition to interviews to determine whether study participants had experienced childhood trauma, all participants underwent screening for depression, anxiety, and posttraumatic stress disorder.
The interviews revealed that:
- 62% of CFS patients reported being the victims of severe childhood traumas compared to 24% of study participants without CFS.
- 33% of CFS patients reported a childhood history of sexual abuse, compared to nearly 11% of study participants without CFS.
- 33% of CFS patients reported being the victims of emotional abuse, compared to 7% of study participants without CFS.
The researchers also tested all participants for levels of the hormone cortisol, which is associated with stress and the so-called "fight or flight" response.
Low cortisol levels may indicate that the body does not respond to stress normally, CFS researcher William Reeves, MD, of the CDC tells WebMD.
Reeves and colleagues found reduced cortisol levels in the CFS patients who had experienced childhood traumas, but not in CFS patients who did not report early-life exposure to trauma.
This suggests that early trauma may "rewire" the brain in a way that makes people more vulnerable to developing chronic fatigue syndrome in adulthood, he says, adding that the finding could have implications for diagnosis and treatment.
"We know that cognitive behavioral therapy works for many people with CFS, and this is especially true for people who have a history of childhood trauma," Reeves says.
Viral Triggers Likely
While 60% of CFS patients had a history of childhood trauma, Komaroff points out that 40% did not and that a significant number of the participants who had experienced severe childhood trauma did not develop chronic fatigue syndrome.
"The danger is that people will jump to the conclusion that early-life trauma causes CFS even though this study showed that a large number of people with CFS had no history of trauma," he says.
Komaroff believes, as many CFS researchers do, that multiple viruses trigger the disorder in people who are vulnerable due to genetics or other reasons.
"I don't believe that any single virus is the cause of CFS in the way that HIV is absolutely critical to causing AIDS," he says.