Past and current thyroid function in subjects with panic disorder.

Disturbances in thyroid function can result in symptoms similar to those occurring in patients with anxiety disorders, especially panic disorder. An association between thyroid illness and panic and phobic disorders has been suggested, but few studies have directly investigated this issue. To assess this possible relationship, the authors measured indices of thyroid function in 165 subjects who had a current DSM-III diagnosis of panic disorder, either with or without phobic avoidance. These subjects reported a higher prevalence of thyroid illness by history compared with the prevalence of thyroid illness in the general population; however, less than 1% of all subjects had current thyroid dysfunction. The presence of a major depressive episode (MDE) was unrelated to current thyroid function, although subjects with MDE reported a higher prevalence of thyroid disease by history. Indices of thyroid function were not correlated with the severity of panic attacks or phobias.