Baseline Cortisol Levels Predict Treatment Outcomes in Chronic Fatigue Syndrome Nonpharmacologic Clinical Trial

Abstract

Objective: Understanding how nonpharmacologic interventions differentially affect the subgroups of patients with chronic fatigue syndrome (CFS) might provide insights into the pathophysiology of this illness. In this exploratory study, baseline measures of normal versus abnormal cortisol were compared on a variety of immune markers and other self-report measures. Normal versus abnormal cortisol ratings were used as predictors in a nurse-delivered nonpharmacologic intervention. Methods: Participants diagnosed with CFS were assigned to 6-month nonpharmacologic interventions. Individuals were classified as having abnormal or normal cortisol levels on the basis of scores over the five testing times. Cortisol levels were considered abnormal if they continued to rise, were flat, or were at abnormally low over time.Results: Across interventions, those with abnormal cortisol at the baseline appeared not to improve over time, whereas those with normal baseline cortisol evidenced improvements on a number of immunologic and self-report measures. Conclusion: It appears that, in subgroups of individuals with CFS, baseline cortisol markers are associated with outcome trajectories for nonpharmacologic treatment trials. The implications of these findings are discussed.

Letter to the Editor: Stratification using biological factors should be performed in more CFS studies

“…The careful work of Roberts and colleagues (2009), in examining possible predictors in the response of Chronic Fatigue Syndrome (CFS) patients to Cognitive Behavioural Therapy (CBT), is to be welcomed. The results are consistent with findings reported by Jason et al (2007). In a study of four non-pharmacological interventions (including CBT), they found that those with abnormal cortisol at baseline did not improve over time, while those with normal baseline cortisol recorded positive outcomes on a number of immunological and self-report measures (cortisol levels were considered abnormal if they continued to rise, were flat, or were at abnormally low over time).…”