Low Free Thyroxine is associated with a higher prevalence of lower extremity arterial disease in Euthyroid Type 2 Diabetes Mellitus

Abstract

Abstract Background Recent studies suggest that higher concentrations of free triiodothyronine (FT3) were associated with a lower prevalence of microangiopathy in adult euthyroid people with type 1 diabetes. This study was performed to identify the association between thyroid hormones and lower extremity arterial disease (LEAD) in euthyroid patients with type 2 diabetes mellitus (T2DM). Methods 1052 T2DM patients with normal thyroid function were enrolled, including 704 patients with LEAD as observation group and 348 patients with T2DM alone as control group. The differences in basic data, biochemical indexes, thyroid hormone between the two groups were compared. At the same time, the correlation between the incidence of LEAD and thyroid hormone was analyzed. Results The logistic regression analysis revealed that FT4 was significantly associated with the incidence of LEAD in T2DM patients, and the prevalence of LEAD increased gradually from the highest FT4 quartile to the lowest FT4 quartile (P < 0.05). Conclusions Patients with low FT4 had a higher prevalence of diabetic LEAD, suggesting that adjusting FT4 levels may better regulate metabolism and thus reduce lower extremity arterial injury.