Biomedicine: 2021; 41(4): 720-723 October - December 2021 DOI: https://doi.org/10.51248/.v41i4.821 Biomedicine- Vol. 41 No. 4: 2021 Research Article Thyroid autoimmunity among type 2 diabetes mellitus: assessing anti-thyroid peroxidase (anti-TPO) antibodies Narendra Kumar Sah 1 , Saurabh Kumar Deo 2 , Harpreet Kaur Walia 3* , Alka Singh 4 , Suvarna Prasad 5 , Kiranjeet Kaur 6 1 Assistant Professor, 3 Associate Professor, 4 Professor & Head, 6 Professor, Department of Biochemistry, Maharishi Markandeshwar, Medical College & Hospital, Kumarhatti-Solan,173229, H.P., India 2 Assistant Professor, Department of Biochemistry, Adesh Medical College & Hospital, Mohri, Kurukshetra, 136135, Haryana, India 5 Professor & Head, Department of Biochemistry, Maharishi Markandeshwar Institute of Medical Sciences & Research, Mullana-Ambala, 133203, Haryana, India (Received: July 2021 Revised: October 2021 Accepted: November 2021) Corresponding author: Harpreet Kaur Walia. Email: dr.harpreet.17@gmail.com ABSTRACT Introduction and Aim: Thyroid disorder, the most abundant endocrine disorder in the globe ranks second after diabetes mellitus. Because of immune resistance to thyroid gland, it leads to the development of hyperthyroidism and hypothyroidism. Autoantibodies against thyroid peroxidase (TPO) - a critical enzyme in the thyroid hormone biogenesis is responsible for thyroid autoimmunity and is increasingly found among type 2 diabetes mellitus (T2DM). So, the present study was designed to assess the serum anti-TPO antibodies among type 2 diabetes mellitus in hospital setting. Materials and Methods: 100 clinically diagnosed type 2 diabetes mellitus was included with 50 age and sex matched apparently healthy controls in the age range 35-70 years. Mean age (in Years) of male and female T2DM cases had 57.40±5.93 and 55.96±7.39 respectively. Also, the male and female controls had mean age as 56.24±8.74 and 54.20±8.90 respectively. Results: The mean glycated hemoglobin (HbA1c) value among T2DM male and female cases was found to be 8.53±2.02% and 8.66±1.90% respectively. The mean value of serum TSH was found to be highly significant statistically among T2DM as compared to healthy controls, whereas mean value of serum anti-TPO antibodies was significant statistically among T2DM as compared to healthy controls. The occurrence of anti-TPO antibodies among T2DM was found to be 13 out of 100 (13%) in the present study. Conclusion: The association between serum TSH and anti-TPO antibodies among T2DM patients was found to be highly significant statistically. Thus, the existence of higher anti-TPO antibodies among T2DM points out the future development of functional thyroid problem in such patients. Keywords: Thyroid peroxidase; thyroid autoimmunity; anti-TPO antibodies. INTRODUCTION ut of 10, one adult will encompass diabetes by 2030; fact indicates that the figure of persons inhabiting with this disorder is anticipated to go up from 366 million in 2011 to 552 million by 2030, if no critical act is undertaken. This figure associates to nearly 3 new victims each 10 seconds or more or less 10 million each year. The figure of adult person having diabetes will amplify to 69% in developing nations and to 20% in developed nations in between 2010 and 2030 (1). It is estimated that in India, there are 50.8 million people with diabetes and the number is projected to rise to 70 million by 2025 (2). Endocrine dysfunctions are growing all over the world. Thyroid disorders are the amplest endocrine disorder in the world second only to DM (3). Auto immune thyroid disease (AITD) like Grave’s disease (GD) and chronic autoimmune thyroiditis (cAIT) happens because of immune resistance to thyroid auto antigens leading to hyperthyroidism and hypothyroidism respectively (4). It is found that there is increased concentration of antibodies against thyroperoxidase (TPO)-a key enzyme involved in organification of iodine and coupling reaction in thyroid hormone production, thyroglobulin (Tg) – protein for iodine integration to form thyroid hormones and TSH receptor (TSH-R) in AITD (5). As the occurrence of AITD is clearly explained among type 1 diabetic patients, the risk of AITD in initially diagnosed T2DM is not known so far (6). As thyroid autoimmunity (TA) implies an unfavourable effect of hypothyroidism patients in insulin sensitivity, the reasonable association between T2DM and TA needs further explanation from both the clinical and research standpoints (7). The proof on the presence of circulating autoantibodies in T2DM in adults has progressively originated since late 1970s, indicating that the type 2 diabetic patients of age >65 years have been associated with anti-GAD (glutamic acid decarboxylase - key enzyme involved in synthesis of γ-aminobutyric acid, inhibitory neurotransmitter found in neurone and endocrine pancreas) and/or anti- insulinoma protein 2 (IA-2) autoantibodies in 12% of O 7