Endocrine Abstracts

Background: Glucose metabolism derangements (GMD) and thyroid nodules (TN) are the most frequent endocrine disorders. A relationship between these conditions has been suggested, but data are still controversial and no evidence was reported regarding sex differences.

Aim: To evaluate the distribution of impaired fasting glucose (IFG), normal glucose tolerance (NGT), impaired glucose tolerance (IGT), type 2 diabetes (T2DM) and TN according to sex.

Methods: Retrospective analysis of 342 patients who underwent both an oral glucose tolerance test and a thyroid ultrasound at our Institution. Only patients with normal TSH levels, with or without replacement therapy (RT), were included.

Results: Most patients were females (78%) and were ≥50 years old. No mean age differences were found among sexes in the whole group and among the different GMD categories. IGT/T2DM rate was higher among patients ≥ 50 years old as compared to younger patients in both sexes (males 66.7% vs. 34.5%, P<0.01; females 43.2% vs. 20.8%, P<0.001). Males presented IGT/T2DM more frequently than females (54% vs. 33%, P< 0.01) even when considering only the 193 patients ≥50 years old (67% vs. 43%, P< 0.01). No differences between sexes were found concerning IFG nor insulin resistance. Total TN prevalence was 61%, with no differences between the sexes. TN prevalence assessed in GMD classes did not show any significant difference. However, within the female group, TN prevalence was significantly higher in ≥ 50 years old subjects as compared to younger females (72% vs. 51%, P<0.01) and in IFG group as compared to no-IFG group (79% vs. 57%, P<0.01). When considering only ≥50 years old females, we confirmed that TN prevalence was higher in the IFG group as compared to no-IFG group (87% vs. 63%, P<0.01). Median thyroid volume (TV) was found significantly higher in males as compared to females (13 vs. 10 ml, P<0.01) in the whole group and among the different GMD categories, except for the IFG group.

Conclusions: Age was confirmed as a risk factor for TN occurrence and GMD. In males, IGT/T2DM prevalence is higher, but no relationship was found with TN occurrence. Furthermore, they showed higher TV in most of GMD categories. Older females present more frequently TNs that occurred more often in patients with IFG. More studies are needed to further explore the relationship between TN and glucose metabolism disorders in order to identify higher-risk population sub-groups.

*The first two Authors equally contributed to the study