Endocrine Abstracts

Introduction: The symptoms and signs of thyroid disease can be subtle and non-specific resulting in the indiscriminate use of thyroid function tests (TFT) for diagnosis. The resulting rise in the number of TFTs has raised issues about cost–effectiveness of such a practice. We set out to identify whether using specific clinical indications was an effective way to identify patients with abnormal TFTs and to determine any demographic data that would support unrestricted TFT requests in individual patients.

Methodology: Case notes and hospital laboratory data were analysed retrospectively in a 2 months period in 2008 for TFT requests. A request was considered to be justified if the patients met pre-determined clinical criteria. Based on this the groups were divided into justified (J) and unjustified (UJ). Thyroidal illness was defined by abnormal FT₄ and TSH levels while an abnormal FT₄ level with normal TSH defining sick euthyriod syndrome (SES).The number of abnormal TFTs and patient demographics in both groups were determined. Group difference was analysed by Students t-testing with a P value of <0.05 significant.

Results: Two hundred and sixty-five frontline requests were identified. The proportion of abnormal TFTs and SES in the J and UJ groups was similar. Abnormal TFTs was three times more likely in the female and elderly (above 80) patient irrespective of group.

Conclusion: Our study demonstrates that the use of specific clinical indications may not be a reliable measure for abnormal TFTs in the elderly and female patients. There is a suggestion that the unrestricted request of TFTs in this group of patients will result in a higher diagnostic rate compared to when specific criteria are applied before testing.