Trajectories of the cortisol awakening responses during weight gain in anorexia nervosa patients with severe and less severe symptoms

• We investigate a sample of AN patients including patients with a very low BMI.
• We examine the cortisol awakening response (CAR) of AN patients.
• Severely ill AN patients show a lower CAR than AN patients with less severe symptoms.
• The differences in CAR between the two groups are due to differences in cortisol levels at 30 min after awakening.
• Results should be interpreted as explorative due to the small sample size.

The aim of this study was to examine the features and changes of the cortisol awakening response (CAR) in patients with anorexia nervosa (AN) with severe and less severe symptoms over the course of inpatient treatment.Our study included n = 20 AN patients who received treatment at the University Hospital, Heidelberg. N = 11 patients were admitted at a psychosomatic and internal-medicine ward that specialized in the treatment of AN patients with a very low BMI (patient group with high symptom severity, HSS). The mean BMI of these patients was 13.2 kg/m2 (SD = 1.4) at the beginning of the study and 16.9 kg/m2 (SD = 1.7) at the end. N = 9 patients were treated at a psychotherapeutic ward where AN patients with less severe symptoms are admitted (patient group with low symptom severity, LSS). The mean BMI of these latter patients was 16.3 kg/m2 (SD = 0.89) at the beginning of the study and 17.1 kg/m2 (SD = 0.65) at the end. Salivary cortisol was measured on two consecutive days respectively, both at the beginning and the end of the study.At the beginning of the study, patients with HSS had a significantly lower mean CAR compared to patients from the LSS group (3.4 nmol/l vs. 11.4 nmol/l). At the end of the study, the mean CAR of patients from the HSS group was still significantly lower compared to the mean CAR of patients with LSS (2.0 nmol/l vs. 9.2 nmol/l).Results indicate that AN patients with severe symptoms exhibit a lower CAR compared to AN patients with less severe symptoms.