Hidden Endocrine Burden: Hypothyroidism in Type 2 Diabetic Patients at Kosti Teaching Hospital, Sudan

Diabetes mellitus (DM) is a common endocrine disorder characterized by persistent hyperglycemia and associated with long-term complications affecting various organs, including the eyes, nerves, kidneys, and endocrine glands. Among these, thyroid dysfunction—particularly hypothyroidism—has been under-investigated in diabetic populations, despite evidence suggesting a higher prevalence among type II diabetic patients compared to the general population. This coexistence may complicate glycemic control and diabetes management. This case-control hospital-based study was conducted at Kosti Teaching Hospital in Kosti City, White Nile State, Sudan, between April 1st and June 1st, 2023. The study enrolled 96 participants, including 66 patients with type II diabetes mellitus (cases) and 30 non-diabetic controls, selected randomly. All participants underwent detailed history taking, clinical examination, and laboratory testing for fasting blood glucose and thyroid hormone levels (T3, T4, and TSH). Data were collected using structured forms and analyzed statistically. The prevalence of hypothyroidism among type II diabetic patients was 19.6%. Among cases, the mean serum levels were: T3 = 0.72 ± 0.54 μg/dL, T4 = 4.01 ± 1.76 μg/dL, and TSH = 10.28 ± 6.96 μIU/mL. TSH elevation was observed in 22.7% of patients, low T4 in 19.6%, and low T3 in 16.6%. No significant correlation was found between thyroid hormone levels and age or sex. Approximately one-fifth of type II diabetic patients were found to have hypothyroidism. This hormonal imbalance may impair glycemic control and exacerbate complications. Routine screening for thyroid dysfunction in type II DM patients is recommended to improve clinical outcomes and reduce morbidity.