Salivary Cortisol in Chronic Fatigue Syndrome

In this study, salivary cortisol were obtained on consecutive days in the first three days of the menstrual cycle and compared in three samples of women taking no medication and matched for age.

There were 14 patients with chronic fatigue syndrome, 26 controls diagnosed with ICD-10 (a physician's code to describe depression episodes) current depressive episodes and 131 healthy controls. The mean evening cortisol was significantly lower in the chronic fatigue syndrome patients compared to controls with depression and healthy controls.

Chronic fatigue syndrome patients without psychiatric disorder had significantly lower morning salivary cortisol compared to the controls. The authors conclude that chronic fatigue syndrome is biochemically distinct from community depression.

(Journal of Affective Disorders [1998], 47 [1-3], 191-194)