FREQUENCY OF THYROID DYSFUNCTION IN NEWLY DETECTED ADULT PATIENTS WITH TYPE 2 DIABETES MELLITUS ATTENDING A TERTIARY CARE HOSPITAL OF BANGLADESH

Ashim Dhar*, Jobaida Naznin, Muhammad Abdul Halim Khan, Devjani Banik, Mohammad Fariduddin, Muhammad Abul Hasanat and Shahjada Selim

ABSTRACT

Background: Thyroid dysfunction and diabetes mellitus (DM) are the two common endocrinopathies but neither causally related nor mutually exclusive. Coexistence of these two conditions is important for management of both the problems. Objectives: To see thyroid dysfunction in newly detected type-2 DM. Materials and Methods: This cross-sectional study was carried out on newly detected type-2 DM patients [n=200, m/f: 81/119; age: 41.1±8.3; BMI (kg/m2): 26.0±4.2; mean±SD] recruited consecutively from the department of Endocrinology, BSMMU. History and relevant clinical examination were recorded. Free thyroxine (FT4), thyroid stimulating hormone (TSH), anti-TPO and anti-TG antibody were tested Chemiluminescence Immunoassay System (Germany). Results: Thyroid dysfunction was observed in 13% subjects. Most of them had subclinical hypothyroidism (8.5%) followed by overt hypothyroidism (3%), subclinical thyrotoxicosis (1.0%) and hyperthyroidism (0.5%). Only 11.5% had family history of thyroid disorder among subjects having dysfunction. About 11% subjects were anti-thyroid antibody positive. Highest frequency for positive anti-thyroid antibody (87.5%) was observed in group having TSH ≥10 m IU/L followed by 66.7% in the group having TSH (5-10) m IU/L, while only 2.8% in the group having TSH <5 m IU/L (p<0.001). There was no significant difference either for level of FT4 (14.0±4.5 vs 14.1±2.2 vs 13.9±1.5; p= 0.925) or for TSH (3.4±5.0 vs 3.7±9.7 vs 2.3±1.6; p= 0.691) or for the antibody status (p= 0.721) among different levels of HbA1c. No significant correlations of FPG, 2Hr75gPPG and HbA1c was found with any of FT4, TSH, anti-TPO and anti-TG antibodies (p= NS for all). Logistic regression revealed anti-TPO antibody as independent predictor for thyroid dysfunction in subjects with diabetes mellitus (p<0.001). Conclusions: The results of the present study suggest that the thyroid dysfunction is not uncommon in newly diagnosed type-2 DM. Thyroid autoimmunity is one of the predictors for increased risk of thyroid dysfunction in them. Screening for thyroid dysfunction may be wise in newly diagnosed type-2 DM.

Keywords: Thyroid dysfunction, Diabetes mellitus, Hypothyroidism.