ASSOCIATION OF THYROXINE WITH INSULIN RESISTANCE IN NEWLY DIAGNOSED HYPERTENSIVES WITH OR WITHOUT DIABETES MELLITUS

Abstract

Abstract Objective: Altered thyroid function is associated with insulin resistance (IR). There are divergent reports regarding association of thyroid function with IR in hypertension and type 2 diabetes mellitus (T2DM). The present study aimed at determining the association between thyroxine (T4), thyronine (T3) or T3/T4 ratio and IR in hypertensives with or without T2DM. Design and method: Cross-sectional study involving newly diagnosed hypertensives with (n = 39) or without T2DM (n = 35) and healthy controls (n = 19). The groups were matched for age, sex and BMI. Fasting blood glucose, glycated hemoglobin, T3, T4, and lipid profile were determined. Homeostatic model assessment of IR (HOMA-IR) was used to determine the level of IR. T3/T4 ratio was estimated and anthropometric variables were recorded. Results: Plasma T3, T4 and T3/T4 ratios were comparable among the groups, however, using multiple regression (stepwise) analysis, there was a strong relationship between T4 but not T3 and IR in hypertensive with (Beta = 0.456, p < 0.001, R2 = 0.208) and without T2DM (Beta = 0.781, p < 0.0001, R2 = 0.610). On the other hand, there was no relationship between T4 and IR in the control group. Conclusions: The findings in the present study indicate that IR could be predicted by T4 but not T3 or T3/T4 ratio in treatment-naïve hypertensives with or without T2DM.