Original Article Association of divalent cations and insulin resistance with thyroid hormones in patients with type 2 diabetes mellitus Rajendran Jayanthi, Abu Raghavan Srinivasan*, Niranjan Gopal, Ramesh Ramaswamy Department of Biochemistry, Mahatma Gandhi Medical College and Research Institute, Sri Balaji Vidyapeeth, Puducherry, India A R T I C L E I N F O Article history: Available online xxx Keywords: Serum zinc Serum magnesium Type 2 diabetes Glycated haemoglobin Insulin resistance Thyroid hormones Dyslipidemia A B S T R A C T Aim: The study was primarily aimed at investigating the association of Magnesium and Zinc levels in the serum of adult Non- obese and Obese type 2 diabetic patients, with particular reference to thyroid comorbidity. Methods: 108 patients with T2DM of both genders (24 Non obese and 84 Obese) were enrolled from a tertiary health care unit in Puducherry. The cardio-metabolic risk factors were assessed through body mass index, Waist hip ratio, blood pressure, fasting blood glucose, lipid profile and glycated haemoglobin. Zinc and Magnesium were quantitated. Insulin resistance was by Homeostasis model assessment. Serum free T4, T3 and TSH were also measured. Results: In non-obese type 2 diabetic group, Glycated haemoglobin had a strong positive correlation with free T4(r = 0.784; p = 0.003).TSH also depicted a positive association with HOMA-IR (r = 0.924; p < 0.001); whereas,T3 and Insulin had negative correlation with Magnesium (r = 0.599* and r = 0.620*; p 0.04 and 0.031). The levels of Zinc and Magnesium in the serum of obese diabetic patients had a positive correlation among them (r = 0.565#; p < 0.001). TAG/HDL ratio a measure of small dense LDL is positively correlated with LDL in both groups (r = 0.881 and 0.912) with p value < 0.001 for both. Conclusion: Correlation among Glycemic control, Insulin resistance, Thyroid hormones, divalent cations and dyslipidemia depict differential characteristics in obese and non–obese type2 diabetes with Thyroid comorbidity. © 2017 Published by Elsevier Ltd on behalf of Diabetes India. 1. Introduction Diabetes mellitus, a common endocrine abnormality affects the metabolism of ions including zinc and magnesium [1]. Diabetes affects nearly 170 million people worldwide or 2% of the world’s population [2,3]. The proposed mechanism of trace elements enhancing insulin action includes activation of insulin receptor sites, serving as cofactors or components for enzyme systems implicated in glucose homeostasis [4,5]. This increases insulin sensitivity and also act as antioxidants [6]. Lower serum levels of magnesium and zinc are observed in patients suffering from type-2 diabetes [7]. It remains to be seen whether difference in trace element status is a cause or effect. The objective of this study was to assess the levels of Zinc and Magnesium in serum in adult non obese and obese type 2 diabetics, but with reference to thyroid comorbidity, in the light of insulin resistance. This dimension has been envisaged, as thyroid comorbidity is frequently linked to insulin resistance in type2 diabetics and also very few reports from South India are available implicating in obese, overweight and non- obese type 2 diabetes, as the case may be. 2. Methodology 2.1. Inclusion criteria 108 patients with T2DM of both genders (24 Non obese and 84 Obese based on Waist circumference for men 85 cm and for women 80 cm) were enrolled from a tertiary health care unit in Puducherry, during the latter half of 2016, with age in the range 30–75 years. Informed consent was obtained from all the participants. This study was conducted with the approval of the Institutional Human Ethics committee (IHEC). 2.2. Exclusion criteria * Corresponding author at: Department of Biochemistry, Mahatma Gandhi Medical College and Research Institute, Sri Balaji Vidyapeeth (Deemed University accredited by NAAC with A Grade), Puducherry 607403, India. E-mail address: raghavan.drvars2000@gmail.com (A.R. Srinivasan). http://dx.doi.org/10.1016/j.dsx.2017.07.010 1871-4021/© 2017 Published by Elsevier Ltd on behalf of Diabetes India. Diabetes & Metabolic Syndrome: Clinical Research & Reviews xxx (2017) xxx–xxx G Model DSX 812 No. of Pages 6 Please cite this article in press as: R. Jayanthi, et al., Association of divalent cations and insulin resistance with thyroid hormones in patients with type 2 diabetes mellitus, Diab Met Syndr: Clin Res Rev (2017), http://dx.doi.org/10.1016/j.dsx.2017.07.010 Contents lists available at ScienceDirect Diabetes & Metabolic Syndrome: Clinical Research & Reviews journal homepa ge: www.elsev ier.com/locate/dsx