Hypothalamic –pituitary–thyroid (HPT) axis functioning in anxiety disorders. A systematic review

Abstract Depression has repeatedly been linked to subclinical hypothyroidism, and thyroid hormones have successfully been used to augment antidepressant treatment. By contrast, the extent of thyroid dysfunction in anxiety disorders remains less clear. This is surprising, given that anxiety‐related symptoms (e.g., nervousness, palpitations, increased perspiration) are highly prevalent in hyperthyroidism. The present study was undertaken to synthesize the literature on hypothalamic–pituitary–thyroid (HPT) axis functioning in anxiety disorders. The PubMed and PsycINFO databases were systematically searched. Three types of studies were included: (1) “comorbidity studies” assessing the prevalence of thyroid disorders in individuals with anxiety disorders, (2) “case‐control studies” comparing HPT parameters between patients and controls, and (3) “correlational studies” assessing self‐reported anxiety levels and HPT parameters. Risk of bias was assessed via a standardized quality rating. Twenty studies were eligible. Nearly all found the comorbidity between anxiety and thyroid disorders was significant. Half of the studies additionally supported the notion of subtle thyroid dysfunction in that thyroid‐stimulating hormone (TSH) responses to the administration of thyrotropin‐releasing hormone (TRH) were blunted and an inverse relationship was observed between self‐reported anxiety levels and TSH. Overall, HPT assessments were well conducted, but several stu...
Source: Depression and Anxiety - Category: Psychiatry Authors: Tags: REVIEW Source Type: research