Changes in salivary cortisol levels as a prognostic predictor in children with anorexia nervosa.

This study investigated the hypothalamus-pituitary-adrenal (HPA) axis activity in children with anorexia nervosa (AN) before and after inpatient treatment. Salivary cortisol levels were measured to ascertain whether changes in the HPA axis activity following therapeutic intervention could be applicable as a prognostic predictor. This study comprised 21 females with AN and 22 control subjects. Saliva was collected at 2-hour intervals from 9 a.m. to 7 p.m. before and after inpatient treatment. The concentrations for areas under the curve (AUC) were compared with physical parameters, eating attitude score, profile of mood states (POMS), and prognostic factors. Mean salivary cortisol levels at all points and mean AUC cortisol levels in subjects with AN before therapy were significantly higher than those in controls, but returned to control levels after inpatient treatment. Higher AUC cortisol levels were associated with lower standard deviation for weight in AN. A significant positive correlation between the AUC cortisol level and POMS subscale of "Fatigue" was apparent in the control group, but not in the AN group. The increased change values of AUC cortisol level before and after inpatient treatment correlated with increased body weight gain ratio just after treatment, but not with the ratio after one year. The present study indicated that HPA axis activity could reflect severity of illness, but did not show an accurate neuroendocrine response for mood states. Changes in HPA axis activity following treatment could therefore be used to predict prognosis and particularly in the short term.