DOI: http://dx.doi.org/10.18203/issn.2454-5929.ijohns20194945

A comparative study on outcomes of preprandial versus postprandial thyroid function test

Vasim Ismail Patel, Akshay B. K.

Abstract


Background: The thyroid is an endocrine gland. It secretes two hormones thyroxine (T4), triiodothyronine (T3). Hypothyroidism is a common condition encountered by a clinician. Subclinical hypothyroidism (SCH) defined as normal free thyroxine (T4) and elevated thyroid stimulating hormone (TSH), is primarily a biochemical diagnosis with or without clinical symptoms. Studies have observed that TSH levels vary at different times in a day. In practice not much importance is given to the timing of the sample collection (pre-prandial or post-prandial sate). SCH is diagnosed depending on TSH value. So the condition may be under or over diagnosed based on a single value. So we conducted this study to determine whether timing of sample collection had any significant relationship in the determination of levels of thyroid hormones.

Methods: The study was carried on 114 patients who visited ENT department, NMCH between July 2018 and June 2019. Group-1 consisted of 38 normal patients. Group-2 consisted of 36 hypothyroidism patients GROUP-3 consisted of 40 subclinical hypothyroidism patients. Thyroid function tests (TSH and free T4) were done in fasting state and 2 hours postprandially.  

Results: TSH values were found to be significantly lowered after food in all the three groups. Free T4 values did not show any statistically significant alteration after food.

Conclusions: There was a significant decline in TSH values postprandially. This might lead to inappropriate diagnosis and management of patients as cases of hypothyroidism, especially in cases of sub clinical hypothyroidism.


Keywords


Thyroid function test, Subclinical hypothyroidism, Thyroid stimulating hormone, Postprandial thyroid function test

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