Clinical assessment of glycated hemoglobin in diabetic hypothyroid patients: A comparison with Euthyroid non diabetic subjects

Abstract

Background: Thyroid disease and diabetes mellitus (DM) are the two most common heterogeneous endocrine disorders in the general population. Both hypothyroidism and type 2 DM are closely involved in cellular metabolism and affect the malfunction of various organ systems. HbA1c was studied for its correlation with thyroid hormones and used for screening, diagnosis, and control of glycemic status.

Objective: To evaluate the validity of HbA1c as a screening and useful test to diagnose hypothyroid patients with pre-diabetes and diabetes.

Methods: The current study was conducted in the Specialized Center for Endocrinology and Diabetes/Baghdad, Iraq from October 2021 to May 2022. The present study was carried out on 115 hypothyroidism patients (92 females and 23 males), and one hundred individuals with normal thyroid function were chosen as a control group. Each patient and individual was investigated for thyroid profile using Vitek immunodiagnostic assay system (VIDAS), while HbA1c was assessed on whole blood by automated chemistry analysis (Analyticom).

 Results: The results showed that most hypothyroid patients were within the age group (24-70) years, which represented 20% ≤(30), 32.2% ≤(40), and 28.7% ≤(50) years. Most hypothyroidism patients were females constituting 80% compared with 20% for males. Most hypothyroidism patients were obese BMI≥30Kg/m² represented 42.7% and overweight     ≥ 25Kg/m² represented 40% compared with 15.7 who were normal weight. The prevalence of diabetes mellitus represented more than two times among the hypothyroidism individuals compared with the control sample, which indicated a highly significant relationship at  Pvalue<0.01. The results also showed that meaningful significant differences were revealed between the two independent groups with highly significant differences at Pvalue<0.01 within the following parameters (HbA1c, Glucose, Thyroid stimulating hormones (TSH), Thyroxine (TT4), Triiodothyronine (TT3).

Conclusion: The present study conclude that the frequency of diabetic patients was significantly increased in hypothyroid population when compared with general population. The use of HbA1c for screening and supported diagnosis assay is necessary to detect and control diabetic patients.