• We studied if insomnia was related to outcomes in the treatment of chronic fatigue.
• A decrease in insomnia severity reduces fatigue in chronic fatigue patients.
• A decrease in insomnia severity improves the cortisol recovery after a stress task.
• Targeting insomnia in the treatment of chronic fatigue may improve outcomes.
The definition of Chronic Fatigue Syndrome (CFS) overlaps with definitions of insomnia, but there is limited knowledge about the role of insomnia in the treatment of chronic fatigue.
To test if improvement of insomnia during treatment of chronic fatigue was associated with improved outcomes on 1) fatigue and 2) cortisol recovery span during a standardized stress exposure.
Patients (n = 122) with chronic fatigue received a 3.5-week inpatient return-to-work rehabilitation program based on Acceptance and Commitment Therapy, and had been on paid sick leave > 8 weeks due their condition.
A physician and a psychologist examined the patients, assessed medication use, and SCID-I diagnoses. Patients completed self-report questionnaires measuring fatigue, pain, depression, anxiety, and insomnia before and after treatment. A subgroup (n = 25) also completed the Trier Social Stress Test for Groups (TSST-G) before and after treatment. Seven cortisol samples were collected during each test and cortisol spans for the TSST-G were calculated.
A hierarchical regression analysis in nine steps showed that insomnia improvement predicted improvement in fatigue, independently of age, gender, improvement in pain intensity, depression and anxiety. A second hierarchical regression analysis showed that improvement in insomnia significantly predicted the cortisol recovery span after the TSST-G independently of improvement in fatigue.
Improvement in insomnia severity had a significant impact on both improvement in fatigue and the ability to recover from a stressful situation. Insomnia severity may be a maintaining factor in chronic fatigue and specifically targeting this in treatment could increase treatment response.
The role of insomnia in the treatment of chronic fatigue, by Håvard Kallestad, Henrik B. Jacobsen, Nils Inge Landrø, Petter C. Borchgrevink, Tore C. Stiles in Journal of Psychosomatic Research 2014 Dec 5. pii: S0022-3999(14)00422-X