PREVALENCE AND CORRELATION OF HYPOTHYROIDISM IN PATIENTS WITH TYPE 2 DIABETES MELLITUS: A TERTIARY CARE CENTRE STUDY

Abstract

Background: Type 2 diabetes mellitus (T2DM) and hypothyroidism are common endocrine disorders that often coexist, potentially worsening metabolic control and cardiovascular risk. Understanding the prevalence of thyroid dysfunction in T2DM and its demographic and clinical correlates is crucial for guiding screening and management strategies.

Objectives: To determine the prevalence of hypothyroidism (overt and subclinical) among T2DM patients, to assess demographic and clinical factors associated with hypothyroidism, and to compare prevalence with non-diabetic controls.

Methods: A cross-sectional study was conducted at a tertiary care centre, enrolling 100 T2DM patients and 100 age- and sex-matched non-diabetic controls. Anthropometry, diabetes duration, HbA1c, and lipid profiles were recorded. Thyroid function was assessed by serum TSH and free T4, with subclinical hypothyroidism defined as elevated TSH with normal free T4, and overt hypothyroidism as elevated TSH with low free T4. χ² tests, Student’s t-test, and logistic regression were used for statistical analysis.

Results: Hypothyroidism prevalence was 22% (95% CI: 14.8–31.0%) in T2DM patients compared with 9% (95% CI: 4.3–16.2%) in controls (p=0.02). Subclinical hypothyroidism predominated (15% in T2DM vs 7% in controls). Female sex was significantly associated with hypothyroidism (68.2% vs 47.4% in males, p=0.04). Higher BMI and longer diabetes duration showed trends toward increased prevalence. Logistic regression revealed T2DM as an independent risk factor for hypothyroidism (OR 2.86, 95% CI 1.24–6.61).

Conclusion: Hypothyroidism is significantly more prevalent among T2DM patients than in non-diabetic controls, particularly in females. Screening for thyroid dysfunction in T2DM, especially in high-risk subgroups, may enable timely diagnosis and improve metabolic outcomes.