Association between the stress hyperglycemia ratio and thyroid nodules in patients with type 2 diabetes

BACKGROUNDThyroid nodules are prevalent, and their occurrence is particularly high in patients with type 2 diabetes mellitus (T2DM).A paucity of research exists on the relationship between the stress hyperglycemia ratio (SHR) and thyroid nodules in patients with T2DM. AIMTo investigate the association between the SHR and thyroid nodules in patients with T2DM. METHODSA single-center, retrospective cross-sectional study design was adopted.The SHR was calculated based on estimated mean blood glucose levels derived from fasting blood glucose and glycated hemoglobin.Patients were divided into four exposure groups (Q1-Q4) according to SHR quartiles; two outcomes were defined, namely the presence vs absence of thyroid nodules (binary outcome) and the nodule count graded as 0, 1, 2, and ≥ 3 (ordinal outcome).Multivariate logistic regression was used to analyze the association between SHR and thyroid nodules.Restricted cubic spline (RCS) models were employed to fit dose-response relationships, and stratified subgroup analyses and interaction tests were conducted. RESULTSStatistical analysis revealed that SHR levels were significantly higher in the group with thyroid nodules than in the group without nodules (P < 0.001).Furthermore, SHR levels exhibited a graded increase as the number of nodules increased (P < 0.001).Multivariate regression analysis revealed a positive and dose-dependent correlation between SHR 4 / 43 and the occurrence of thyroid nodules.In comparison with the Q1 group, the Q4 group exhibited a 3.49-fold elevated risk of developing thyroid nodules [odds ratio (OR) = 4.49, 95% confidence interval (CI): 1.97-10.22,P < 0.001].Concurrently, the probability of an escalation in the number of nodules was found to be 2.68-fold heightened (OR = 3.68, 95%CI: 1.91-7.08,P < 0.001).A restricted cubic spline analysis revealed that, in the absence of confounding factors, SHR demonstrated a non-linear positive association with the risk of thyroid nodules (P for non-linearity = 0.032), with the risk rising more steeply across the lower SHR range, whereas the slope flattened at higher SHR values while remaining positive.Subgroup analyses showed that the association remained robust across most subgroups, with no significant interaction in any stratum except for insulin use (P for interaction = 0.011), under which the association was stronger among insulin users. CONCLUSIONElevated SHR has been shown to be independently associated with an increased risk of thyroid nodules, and a higher number of nodules in hospitalized patients with T2DM.