Numerous studies of patients with long standing chronic fatigue syndrome (CFS) have found alterations to the hypothalamus-pituitary-adrenal (HPA) axis including hypocortisolism (low cortisol) (Cleare, 2004). The HPA axis asists in regulating temperature, digestion, immune system, mood, sexuality and energy production. However, it is strongly involved in controlling reactions to physical and emotion stress. Cleare (2004) informs us that reduced levels of cortisol, stress hormone, can potentially have a marked symptomatic effect on the body. For example, there is evidence to suggest that some patients with chronic fatigue experience an alleviation of symptoms when hypocortisolism is reversed (Cleare, 2004). Hence, low cortisol levels may act as a maintaining factor in chronic fatigue syndrome. In a study conducted by researchers at Cambridge University, London, 32 patients diagnosed with chronic fatigue syndrome were administered consecutive low dose hydrocortisone therapy (5-10 mg daily) for one month (Cleare, Heap, Malhi, Wessley, O'Keane & Miell, 1999). In this study it was found that self-reported fatigue scores fell by 7.2 points for CFS patients using administered low dose hydrocortisone. This being so, extended treatment time and follow up studies are required to find out whether the effect could be clinically useful.
Cleare, A.J. The HPA axis and the genesis of chronic fatigue syndrome. Trends in Endocrinology Metabolism, 15, 2, 55-59.
Cleare, A.J., Heap, E., Malhi, G.S., Wessely, S, O'Keane, V. & Miell, J. 1999. Low dose hydrocortisone in chronic fatigue syndrome: a randomised crossover trial. Lancet, 353, 455-459.