Alexithymia and cortisol awakening response in people with eating disorders

Alexithymia, which is the inability to recognise and describe one's own emotions, is a transdiagnostic feature across eating disorders (EDs) and it has been associated with prolonged stress exposure. Therefore, we evaluated whether alexithymia was associated with hypothalamus-pituitary-adrenal (HPA) axis functioning, the main endogenous stress response system, in patients with anorexia nervosa (AN) or bulimia nervosa (BN).

26 women with AN and 26 with BN participated in the study. Alexithymia was evaluated by the Toronto Alexithymia Scale-20 and eating-related psychopathology was measured by the Eating Disorder Inventory-2. The activity of the HPA axis was assessed by measuring the salivary cortisol awakening response (CAR).

The prevalence of alexithymia did not differ significantly between the two diagnostic groups. Alexithymia was associated with more severe eating-related psychopathology in AN women but not in BN women. A significant reduction in the magnitude of CAR occurred in alexithymic patients with BN compared to non-alexithymic patients, but not in alexithymic women with AN.

These results confirm the presence of a more severe specific psychopathology in alexithymic individuals with AN and show, for the first time, an association between alexithymia and a dampened basal activity of the HPA axis in BN.