Free Triiodothyronine Levels Are Associated with Diabetic Nephropathy in Euthyroid Patients with Type 2 Diabetes

Abstract EN

Objective.

To investigate the association of thyroid function and diabetic nephropathy (DN) in euthyroid patients with type 2 diabetes.

Methods.

A total of 421 patients were included in this cross-sectional study.

The following parameters were assessed: anthropometric measurements, fast plasma glucose, serum creatinine, lipid profile, HbA1c, free triiodothyronine (FT3), free thyroxine, thyroid-stimulating hormone levels, and urinary albumin-to-creatinine ratio (UACR).

Patients with UACR of ≥30 mg/g were defined as those suffering from DN.

Results.

Of the 421 patients, 203 (48.2%) suffered from DN, and no difference was found between males and females.

The patients with DN yielded significantly lower FT3 levels than those without DN (P<0.01).

The prevalence of DN showed a significantly decreasing trend across the three tertiles based on FT3 levels (59.6%, 46.4%, and 38.6%, P<0.01).

After adjustment for gender and age, FT3 levels were found to correlate positively with estimated glomerular filtration rate (P=0.03) and negatively with UACR (P<0.01).

Multiple linear regression analysis showed that FT3 level was independently associated with UACR (β=-0.18, t=-3.70, and P<0.01).

Conclusion.

Serum FT3 levels are inversely associated with DN in euthyroid patients with type 2 diabetes, independent of traditional risk factors.