Association Between Elevated Thyroid Peroxidase Antibody and Abdominal Fat Distribution in Patients with Type 2 Diabetes Mellitus

OBJECTIVE: Obesity and autoimmune thyroid disease (AITD) are both common disorders in the general population, which are major drivers for adverse medical conditions. While an interaction between thyroid function and visceral obesity is thought to exist, but very few studies have examined the relationship between AITD and visceral obesity, especially in the patients with type 2 diabetes mellitus (T2DM). In the present study, we investigated the association between elevated thyroid peroxidase antibody (TPOAb) titer and visceral fat area in T2DM patients. METHODS: A total of 390 T2DM patients who met the criteria for admission and joined the National Metabolic Management Center (MMC) in the Zhejiang Provincial People’s Hospital from April 2020 to December 2020 were enrolled in this study. The participants were divided into two groups based on visceral obesity. Thyroid function, thyroid associated antibody and other metabolic indicators were measured by blood tests. The visceral fat area (VFA) and the subcutaneous fat area (SFA) were measured by bioelectrical impedance analysis. RESULTS: There were 185 participants (47.4%) had visceral obesity. The positive rate of TPOAb was significantly higher in T2DM patients with visceral obesity (12.97% vs 5.37%, p < 0.01). Free triiodothyronine (FT3) and thyroid-stimulating hormone (TSH) were both significantly higher in T2DM patients with visceral obesity (p < 0.05). The increased TPOAb titer was significantly positively correlated with visceral fat area (r = 0.175, p < 0.01). Binary logistic analysis showed that the positive rate of TPOAb was associated with an increased risk of visceral obesity [(OR) 4.258, 95% confidence interval (CI) 1.594, 11.375, p = 0.004]. CONCLUSION: TPOAb-positive is more common in T2DM patients with visceral obesity, which has some effects on visceral obesity independent of thyroid function. This suggests that elevated TPOAb titer is a predictor of visceral obesity in T2DM patients.