Endocrine Abstracts

Background: Current UK guidelines for the Use of Thyroid Function Tests provide specific recommendations for the use of thyroid function tests in inpatients. Isolated alterations in TSH occur in 15% of inpatients and <2% will have underlying thyroid disorder. Thyroid function should be repeated every 4–6 weeks when changing thyroxine replacement dose or when commencing thionamides.

Aim: To identify the indications and frequency of thyroid tests in medical inpatients and to address their use in the acute setting.

Methods: 78 patients from 7 medical wards (excluding medical admissions unit) who had thyroid function tests at least once during hospital stay were randomly selected over a two weeks period. The indications and frequency of thyroid function testing, length of hospital stay and change in management were identified.

Results: 57 (72%) of inpatients had thyroid function tests measured once during their admission, 17(22%) twice, and 4(6%) three or more times. In this sample group the mean hospital stay was 12.3 days and thyroid function tests were requested 1.4 times per patient.

Admission with arrhythmia was the commonest reason for requests in cardiology patients (38.5%). In the Care of The Elderly wards TSH was part of dementia screen, as recommended by the NICE guidelines and was tested in 42% of elderly inpatients. In only one patient did an abnormal TSH result alter management. In all other cases, patients were tested to exclude thyroid related problems and thyroid tests were either within normal limits or disturbed in a way that no immediate management was needed.

Conclusion: Repeated thyroid testing in hospitalized patients has limited clinical value and can be misleading. Thyroid tests in general medical in-patients are mainly used to exclude rather than confirm existing thyroid pathologies.