The Headline:

“Low levels of the stress hormone cortisol marks out children at higher risk of developing chronic fatigue syndrome as adults,” reported the BBC today. It said that if children with low levels of cortisol are exposed to trauma such as sexual abuse, they are six times more likely to develop the condition when older.

NHS Choices says that:

This was a relatively small study, which may provide some early evidence of a link between psychological and biological risk factors for CFS. There are some limitations to note, however:

  • Although people with CFS reported more childhood trauma, this type of study cannot conclusively prove that the childhood trauma itself “caused” CFS because other factors may be responsible for the apparent link. For example, other illnesses in childhood, abuses outside of the family unit and adult trauma were not considered or adjusted for.
  • There may be differences in how individuals rate or recall their experiences of trauma, and this could have affected the results. The authors acknowledge that there may be problems in relying on “retrospective and uncorroborated self reports” of childhood experiences and suggest that simply forgetting the trauma, not disclosing it, or other biases, may have partly accounted for the difference between the groups.
  • This study only measured cortisol levels in adults who were already known to have or not have CFS. Therefore it cannot indicate whether cortisol levels in childhood owuld be able to predict risk of CFS in later life. As CFS is relatively rare, this type of test by itself would be unlikely to help identify those at risk.

Although this study cannot prove that childhood trauma itself “causes” CFS, or that childhood cortisol levels can predict CFS in adulthood, this study contributes to knowledge about potential risk factors for CFS. Much more research is needed to fully understand the causes of this complex condition.

Links to the Headlines:

Stress hormone 'a marker for ME'. BBC News, January 6 2009

Links to the Science:

Heim C, Nater UM, Maloney E, et al. Childhood Trauma and Risk for Chronic Fatigue Syndrome. Arch Gen Psychiatry 2009; 66: 72-80

Further readingPrice JR, Mitchell E, Tidy E, Hunot V. Cognitive behaviour therapy for chronic fatigue syndrome in adults. Cochrane Database of Systematic Reviews 2008, Issue 3