In a clinical sample of 116 children and adolescents we studied the relation between the course of an anxiety disorder during treatment and the concomitant changes in cortisol levels. Assessments... Show moreIn a clinical sample of 116 children and adolescents we studied the relation between the course of an anxiety disorder during treatment and the concomitant changes in cortisol levels. Assessments at base-line, after three months, and at one-year follow-up were performed with the Anxiety Disorders Interview Schedule. When we compared cortisol levels at baseline and one-year follow-up, persistence of the anxiety disorder was associated with both increased daytime cortisol production (F = 3.2, p = 0.04) and a trend towards a decreased cortisol morning rise (F = 2.4, p = 0.09). At one-year follow-up daytime cor-tisol production was lowest in the early remitters (109.7 ± 29.2 h mmol/l), higher in the late remitters (121.0 ± 40.0 h mmol/l) and highest in the non-remitters (131.1 ± 48.9 h mmol/l). Early remitters had the highest cortisol morning rise (1.1 ± 1.5 h mmol/l), followed by the late remitters (0.8 ± 1.8 h mmol/l), the non-remitters had the lowest cortisol morning rise (0.07 ± 1.7 h mmol/l). Persistence of an anxiety disorder may thus lead to changes in HPA-axis functioning, underscoring the importance adequate treatment of anxiety disorders. Show less