Thyroid hormones in panic disorder, panic disorder with agoraphobia, and generalized anxiety disorder.

Fifty-two patients with generalized anxiety disorder who had symptoms persisting for at least 6 months, 41 patients suffering from either panic disorder (32 patients) or panic disorder with agoraphobia (9 patients), and 14 control subjects were screened for thyroid disease. Total serum thyroxine (TT4), serum-free thyroxine index (FT4I), and triiodothyronine resin uptake (T3RU), were examined for the entire sample, using a one-way analysis of variance (ANOVA). No significant differences were found in TT4 (p = .24), FT4I (p = .24), and T3RU (p = .19). Thyroid-stimulating hormone (TSH) was examined in a subsample of 10 patients with generalized anxiety disorder, 11 with panic disorder or panic disorder with agoraphobia, and 10 controls. One-way ANOVA again showed no significant differences, although there was a trend (p = .07). This is the first report that compares generalized anxiety disorder patients, panic disorder patients, and patients with panic disorder and agoraphobia with controls on measures of thyroid function. It is also the first to report normal values in the thyroid indices of generalized anxiety disorder patients.