Low Cortisol Levels May Be Risk Factor in Developing Chronic Fatigue Syndrome

We all occasionally get tired, depressed, and run down, but between 1 and 4 million Americans suffer from a disorder that causes long-term and sometimes debilitating tiredness that is not relieved by rest or sleep—a condition called myalgic encephalomyelitis (ME), more commonly referred to as chronic fatigue syndrome (CFS). Those suffering from ME/CFS not only deal with extreme mental and physical exhaustion, but also a wide range of other symptoms, including flu-like symptoms, widespread muscle and joint pain, and cognitive difficulties. ME/CFS is hard to diagnose because no single diagnostic test exists and its symptoms often mimic those of many other disorders, such as fibromyalgia, mononucleosis, Lyme disease, and major depressive disorders. Another problem is that there is no identifiable cause of the illness, although many hypotheses have been proposed. Many researchers believe at least some cases of ME/CFS are caused by an abnormal reaction to common infectious agents, although studies have fallen short of proving a consistent causal link. Other experts suspect that something called central sensitization is at least partially to blame. However, scientists believe they have discovered another marker likely to trigger ME/CFS—childhood trauma.

Researchers from Emory University School of Medicine in Atlanta, Georgia compared 113 adults with ME/CFS to a control group of 124 without the illness. The participants were asked to complete a questionnaire on five different types of childhood trauma including emotional, physical and sexual abuse, and emotional and physical neglect. They also gave saliva samples that were checked for cortisol, a hormone that regulates the body’s response to stress.

The researchers found that 62 percent of the participants with ME/CFS had suffered a childhood trauma in comparison with 24 percent who hadn’t experienced trauma. Although not all of those with ME/CFS had been abused as children, and not all with traumatic childhoods went on to develop the illness, the individuals with a history of childhood trauma with ME/CFS all had lower than normal cortisol levels. The researchers also found that a greater proportion of ME/CFS patients had severe depression, high-state anxiety and clinical posttraumatic stress disorder symptoms, compared with the control group. “Stress in interaction with other risk factors likely triggers chronic fatigue syndrome symptoms through its effects on central nervous, neuroendocrine and immune systems,” the study’s authors said.

According to the CDC, the first credible evidence of a biological basis for ME/CFS came in 2006, when twenty researchers from different specialties each linked the illness with genes involved in the sympathetic nervous system and what’s called the HPA axis. These genes control how your body responds to things like stress and injuries.

“Childhood trauma has been linked to a higher incidence of all kinds of medical problems over the years and ME is no exception—but it is important to make one thing crystal clear. A diagnosis of ME does not mean that a patient has been mistreated or had a bad childhood,” said Sir Peter Spencer, CEO of Action for ME. “ME may be triggered by a wide range of factors including glandular fever, chickenpox, shingles, viral meningitis, gastroenteritis, salmonella and Lyme disease. The main conclusion that I draw from this rather limited study is the urgent need for much more biomedical research into the causes, risk factors, and development of this very distressing illness.”

“The study indicates that low levels (of cortisol) may actually reflect a marker for the risk of developing CFS rather than being a sign of the syndrome itself. When looking at CFS cases with and without histories of childhood trauma, only those with childhood trauma had the classic low cortisol levels often seen in CFS cases,” said lead researcher Dr. Christine Heim. “Trauma that occurs at different times in childhood may be linked to different long term changes. It’s an area in which more work is needed.”

Currently, treatment for ME/CFS can include prescription or over-the-counter medications to help with specific symptoms, complementary or alternative therapies and emotional support. Common drugs are antidepressants, antivirals, allergy medications, anti-inflammatory drugs and immune-system boosters. Some medical practitioners recommend dietary changes, herbal or nutritional supplements, homeopathic remedies and acupuncture. Some sufferers also benefits from counseling, support groups and stress-reduction techniques because ME/CFS can be an extremely stressful condition. Also being researched are psychostimulants, which may help with memory and concentrations problems; D-ribose, which improves cellular function and may help with energy, sleep, mental clarity and pain reduction; and antibiotics, which can help level out the immune system.

The study, supported by the federal Centers for Disease Control and Prevention (CDC), was published in the Archives of General Psychiatry.