“A Comparative Study of Serum Insulin Levels and Insulin Resistance in Patients Suffering with Hypothyroidism and Healthy Controls”

Abstract

Background Glucose homeostasis is influenced by thyroid hormones and this homeostasis is disturbed in hypothyroidism which further results in insulin resistance.

Aim and Objectives Present study was conducted to evaluate the levels of fasting blood glucose, fasting insulin levels and insulin resistance in diagnosed female hypothyroid patients and normal controls.

Materials and Methods

The current study was a hospital based observational cross sectional study which was conducted in the department of Biochemistry in collaboration with department of Medicine, Faculty of Medicine and Health Sciences, SGT University, Gurugram, Haryana. Study was conducted on total 160 subjects. Among these 80 hypothyroid females were taken as cases and 80 age matched healthy individuals as controls. Fasting blood samples were collected from all subjects included in the study and evaluated for fasting plasma glucose, fasting Insulin and thyroid profile (FT3, FT4 and TSH). Fasting Insulin and thyroid profile were estimated by chemiluminescence immunoassay (CLIA) on MAGLUMI 1000 fully autoanalyser. Fasting blood glucose was estimated by glucose oxidase- peroxidase (GOD-POD) method on Erba 360 fully autoanalyser. Insulin resistance was estimated Insulin resistance was calculated by homeostatic model index (HOMA IR=fasting insulin (µIU/ml) x fasting glucose (mg/dl) /405).  Results were subjected to statistical evaluation and presented as mean ± SD. P value (≤ 0.05) was considered as statistically significant.

Results:

It was observed that the mean age ± SD of cases was 34.01 ± 8.28 years and for controls it was 32.59 ± 7.76 years with no significant difference. The mean serum TSH, fasting glucose, fasting insulin and insulin resistance were significantly increased (p<0.001) in hypothyroid patients compared to controls. In contrast the mean serum FT3 and FT4 were significantly (p<0.001) in patients compared to controls. It was also observed that there was a significant positive correlation (r = 0.846) between serum TSH levels and Insulin resistance in hypothyroid patients.

Conclusion:  The results demonstrated that hypothyroidism was associated with increased insulin levels and insulin resistance.