Somatic symptoms in children with anxiety disorders: an exploratory cross-sectional study of the relationship between subjective and objective measures.

Symptoms of childhood anxiety disorders include activation of bodily stress systems to fear stimuli, indicating alterations of the autonomic nervous system (ANS). Self-reported somatic symptoms are frequently reported, while studies including objective measures of ANS are scarce and show inconsistent results. Even less studied is the relationship between subjective and objective measures of somatic symptoms in anxious children. Increased knowledge of this relationship may have relevance for treatment programmes for anxiety disorders. This cross-sectional study examined subjective and objective measures of ANS responsiveness in a clinical sample of children with anxiety disorders (7-13 years; n = 23) and in healthy controls (HC; n = 22) with equal distributions of gender and age. The subjective measure used was the Multidimensional Anxiety Scale for Children, which includes a subscale on somatic symptoms. The objective measures consisted of an orthostatic challenge (head-up tilt test), and an isometric muscular exercise (handgrip) while the participants were attached to the Task Force Monitor, a combined hardware and software device used for continuous, non-invasive recording of cardiovascular variables. The anxiety disorder group reported significantly more somatic symptoms than HCs (both by mother and child reports). In contrast, no relevant differences in cardiovascular variables were demonstrated between the anxiety group and HCs. Finally, there were no significant correlations between subjective and objective measures in either group. Because of the small sample size, the findings must be interpreted carefully, but the results do not support previous reports of functional alterations of the ANS in anxious children.