Title: Study of Antithyroid Peroxidase Antibodies in People with Normal Range Thyroid Stimulating Hormone

Authors: Dr Simi Sam, Dr Minny Mary Mammen

 DOI:  https://dx.doi.org/10.18535/jmscr/v5i2.141

Abstract

Aims and Objectives: Hypothyroidism has become a common health issue in India, as it is worldwide. However, there is a lack of adequate information on the prevalence of hypothyroidism in the adult population of India. In this study we evaluated the presence of antithyroid peroxidase antibodies in people with high normal and low normal range thyroid stimulating hormone levels.

Methods: The staffs of Government Medical college, Thiruvananthapuram, with symptoms of thyroid dysfunction in the age group of 15-35 years were included in this study, with exclusion of those with other systemic illness and conditions which alter the thyroid stimulating hormone values. In this study, the normal range of thyroid stimulating hormone is taken as 0.36-5.49 µIU/ml The study population then divided into two groups based on the high(2.5-5.49 µIU/ml) and low(0.36-2.49 µIU/ml) normal range values of thyroid stimulating hormone. In both these groups all were evaluated for anti-TPO levels.

Results: In our study, even if it was done in a group of people with normal TSH levels, about 58.1 % have positive TPOAb values (> 75 U/ml) in which 70.3% is from the people with high normal TSH values (2.5-5.49 µIU/ml). In our study we observed that the people with thyroid related complaints are more in females and constitutes about 62.2 % in the study group. In the evaluation of TPOAb positivity also there is a strong female preponderance (74.4%) These findings carries a strong statistical significance.

Conclusion: Anti TPO antibody measurements in those with high normal range TSH value may be considered to identify the patients at risk of developing true hypothyroidism in future so that early commencement of LT4 therapy is possible to diminish the autoimmune thyroid destruction Or else we may reconsider the “normal range” of TSH so that most of the patients with high antibody titre will fall in the diagnosis of subclinical hypothyroidism.

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Corresponding Author

Dr Simi Sam