A U.S. study of 237 people by researchers from Emory University in Georgia has found that childhood trauma, particularly emotional maltreatment and sexual abuse is associated with a sixfold increase in the risk of chronic fatigue syndrome. The study compared people with and without chronic fatigue who completed a questionnaire on five different types of childhood trauma including emotional, physical and sexual abuse and emotional and physical neglect. The researchers also collected saliva samples from the participants to measure the levels of the stress hormone cortisol and found that low levels of the hormone - often a symptom of chronic fatigue syndrome - were associated with childhood trauma. Of the people suffering from chronic fatigue syndrome only those who had suffered childhood trauma had low levels of cortisol.
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