Correlation Between Thyroid Nodules and Insulin Resistance in Egyption Patients Without Diabetes Mellitus

Background: Thyroid nodules [TNs] exhibit a higher prevalence in individuals with type 2 diabetes mellitus compared to those without diabetes. The underlying mechanisms encompass insulin resistance, enhanced oxidative stress, and elevated thyroid stimulating hormone levels.The aim of the work: This study aimed to study the association between clinically relevant thyroid nodules and insulin resistance in euthyroid individuals without diabetes mellitus.Patients and Methods: This case-control study was conducted on sixty-two patients presenting concerns regarding thyroid nodules at the Endocrinology Outpatient Clinic at Al-Azhar University Hospital in Damietta. Further, fifty-three healthy volunteers, matched for age, sex, and body mass index, were selected as a control group without clinical, laboratory, or radiological evidence of thyroid dysfunction. The thyroid profile and the Homeostatic Model Assessment for Insulin Resistance [HOMA-IR] were determined for all participants. In addition to clinical assessment, the thyroid was evaluated using ultrasonographic imaging.Results: HOMA-IR was significantly higher in subjects with thyroid nodules compared to controls [P<0.001] and elevated HOMA-IR was an independent predictor of thyroid nodule occurrence. The cutoff point of HOMA-IR above which thyroid nodularity risk increased was 1.59 with 85.48% sensitivity and 86.79% specificity [AUC=0.874, P<0.001]. Nevertheless, HOMA-IR didn’t differ among individuals with either solitary or multiple nodules and it shows no significant variations concerning the Thyroid Imaging Reporting and Data System [TIRAD] scoring [P<0.57].Conclusion: Our findings suggest that HOMA-IR serves as a reliable marker for distinguishing patients with substantial thyroid nodules. However, no correlation between this marker and the TIRAD score was observed.