LAUSR

BACKGROUND In chronic fatigue syndrome (CFS) little is known about how partner-related factors influence patients' fatigue symptoms and treatment outcome. We examined partners' fatigue severity, and determined the role of partner-related factors for patients' symptoms and the outcome of cognitive behavioural therapy (CBT). METHODS 1356 CFS patients and their partners completed baseline measures of fatigue severity (Checklist Individual Strength), causal attributions of symptoms, partner responses to patient symptoms, and relationship satisfaction. Fatigue in partners of patients with CFS was compared with fatigue in age- and gender-matched controls from the Dutch population. Associations between partners' fatigue severity and other partner-related factors were determined. In a subgroup of 760 CFS patients who completed CBT, logistic regression analyses were used to identify partner-related baseline predictors for treatment outcome (fatigue severity, functional impairment). RESULTS Partners' fatigue (M = 21.66, SD 11.60) was significantly lower than in controls (M = 24.58, SD = 11.02) (p < .001) and not related to patients' fatigue (r = -0.02, p = .58). Partners' fatigue was correlated with patients' functional impairment (p = .001), partners' and patients' relationship dissatisfaction, negative partner responses, and partners' and patients' psychological attributions of patient symptoms at baseline (all p < .001). After controlling for patients' baseline fatigue severity and functional impairment, only relationship dissatisfaction as reported by (female) patients significantly predicted worse treatment outcome. For male patients with female partners, higher partners' fatigue severity predicted higher fatigue severity after CBT. CONCLUSIONS Female partners' fatigue and relationship dissatisfaction as reported by the female patient should be addressed in CBT for CFS, as these factors affect treatment outcome.