Thyroid function testing in an inpatient mental health unit

OBJECTIVE: Thyroid function tests are a common screening investigation for patients admitted to a psychiatric inpatient unit. METHOD: This study aimed to retrospectively assess the clinical utility of routine thyroid function testing performed on newly admitted psychiatric patients over a 4-year period in Victoria, Australia via chart review of all abnormal results identified. RESULTS: Our retrospective audit revealed only two cases where identification of thyroid dysfunction informed patient management. In each case, the patient had a known history of thyroid disease. In this audit period, 893 patients required screening to yield one clinically relevant abnormal result, costing AU$24,975.57. CONCLUSION: Such low clinical utility does not support routine admission thyroid function tests for psychiatric inpatients. We conclude that thyroid function tests should only be performed where the history and clinical signs suggest a likely contribution of thyroid dysfunction to the psychiatric presentation.