Introduction: Saliva as an alternative biological fluid of choice to blood in diagnosing systemic diseases evolved due to its noninvasive nature of collection. There is little information on the levels of thyroid stimulating hormone (TSH, thyrotropin) and T3 levels in saliva. The study was thus taken up to study the suitability of saliva for measurement of thyroid hormones in comparison to serum.

Materials and methods: Fasting saliva and serum samples were collected from 30 healthy individuals for the measurement of total T3 (TT3), total T4 (TT4), TSH, free T3 (FT3), and free T4 (FT4). Timed samples were collected from 10 subjects for the evaluation of diurnal variation.

Results: The thyroid hormones studied, i.e., TT3, TT4, FT4 and TSH were significantly higher in serum when compared to saliva (p < 0.01). A significant positive correlation was found between serum and salivary TSH (r = 0.420, p = 0.001). Variations in salivary TSH reflected the pattern seen in serum TSH. However, there was a lack of agreement between the measurement of TSH in serum and saliva when assessed using Bland Altman and Mountain plots.

Conclusion: Saliva cannot be used as an alternate sample for analysis of thyroid hormones.

Keywords: Saliva, Serum, Thyroid hormones.

How to cite this article: Naresh S, Bitla AR, Sachan A. Utility of Saliva for Measurement of Thyroid Hormones. Indian J Med Biochem 2018;22(1):36-40.

Source of support: Sri Balaji Aarogya Varaprasadini Scheme (SBAVP) of SVIMS, TTD.

Conflict of interest: None