Panic, suicide, and agitation: independent correlates of the TSH response to TRH in depression.

We investigated the relationship between suicidality, agitation, panic attacks, and the thyrotropin-stimulating hormone (TSH) response to thyrotropin-releasing hormone (TRH), and tested the hypothesis that panic would account for the association between a reduced TSH response and the other conditions. Twenty-seven euthyroid primary unipolar depressed inpatient women received a TRH test and systematic psychiatric assessment. Panic attacks were insufficient to explain the link between the TSH response and suicidal intent, lethality, and agitation; each condition was independently associated with a lower TSH response. In an additive fashion, copresence of conditions further reduced TSH response. The symptom constellation of panic, agitation, and suicidality in depression may correlate with the greatest reduction in TSH response.