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

Abstract

ABSTRACTObjective: 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 o...