Estimation of FT3, FT4 and TSH Levels Among Different age-sex Groups of Healthy Population in Rajshahi city

Background: Thyroid is an endocrine gland which is located below the larynx. The principal hormones of thyroid gland are thyroxine (T4), and tri-iodothyronine (T3). The activity of the thyroid gland depends on the age as well as gender. However, with advancing age the concentration of these hormones decreases in apparently healthy male and female. The current study was carried out to investigate the impact of age and gender on the level of free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) in apparently healthy individuals. Objective: This study was designed to observe the levels of FT3, FT4 and TSH among different age-sex groups of normal healthy population residing in Rajshahi City. Methods: This cross-sectional descriptive study was carried out in the department of physiology in collaboration with institute of nuclear medicine and Allied Sciences, Rajshahi. 120 apparently healthy persons in age group of 8-65 years were studied. Random blood sample was taken to measure the level of free T3, free T4, TSH by Radioimmunoassay (RIA) and Immunoradiometric assay (IRMA). Data were analyzed by ANOVA Test and independent t test. Result: Non-significant drop of FT4, TSH level and significant drop of FT3 level with advancing age. Moreover, mean FT3, and FT4 concentration is non-significantly higher in male in comparison to female. However mean TSH concentration is significantly higher in male in comparison to female. Conclusion: It can be concluded from the present study that non-significant drop of FT4, TSH level and significant drop of FT3 level with advancing age.