Associations of Thyroid Hormone Levels and Macrovascular Complications in Euthyroid Type 2 Diabetic Patients

Abstract

Purpose The purpose of this study is to evaluate whether thyroid hormone in euthyroid patients with type 2 diabetes mellitus (T2DM) is associated with macrovascular complications. Patients and Methods The authors examined 311 patients enrolled from February 2019 to December 2019 in Tianjin Medical University Chu Hsien-I Memorial Hospital. A medical record review enabled the collection of demographic and anthropometric information. We classified the patients into two groups based on the echocardiography and vascular ultrasonography results, namely, non-macrovascular complications (n=131) group and macrovascular complications (n=180) group. Odds ratios (OR) and 95% confidence intervals (CI) were calculated, adjusting for potential confounders, the prevalence of macrovascular complications was determined using multivariate logistic regression. Results A significant association was observed for diabetic macrovascular complications with normal free triiodothyronine (FT3) (OR=0.534, 95% CI 0.358–0.796, p = 0.002) and free thyroxine (FT4) (OR= 0.844, 95% CI 0.760–0.937, p = 0.001). Nevertheless, there was no evidence of any association between thyroid-stimulating hormone (TSH) and the development of diabetic macrovascular complications. When stratified by the body mass index (BMI), a similar relationship existed with the overall results. The positive association remained in restricted analyses involving only patients with HbA1c abnormalities. Conclusion Overweight or obese T2DM patients are at high risk due to the implicit association between low but clinically normal thyroid hormone levels and elevated risk of macrovascular complications. However, there were no statistically significant associations between TSH and diabetic macrovascular complications.

Serum free triiodothyronine is inversely associated with diabetic peripheral neuropathy but not with carotid atherosclerotic lesions in euthyroid patients with type 2 diabetes

“…This discrepancy can be explained by the fact that the different definitions of macrovascular complications were used in above studies. That is, the macrovascular complications in the studies by Wang et al [ 38 ] and Hu et al [ 12 ] were defined as atherosclerosis from the aorta, coronary, basilar and carotid, while our current study mainly focused on carotid atherosclerotic lesions.…”

“…Recently, a study by Wang et al [ 38 ] displayed that diabetic patients with low-normal FT3 level were more likely to suffer from macrovascular complications than those with mid-and-high normal FT3 level. Hu et al [ 12 ] also revealed that there was a remarkable relation between diabetic macrovascular complications and normal FT3 (OR = 0.534, 95% CI 0.358–0.796). Partly consistent with the above studies, we found that patients in the lower FT3 quartiles were more prone to carotid atherosclerotic lesions than patients in the higher FT3 quartiles.…”

“…Furthermore, several recent studies have reported that close relations are observed between low-normal FT3 levels and type 2 diabetic macrovascular and microvascular complications [ 12 , 13 ]. For example, Wu et al [ 13 ] revealed that the occurrence of DN exhibited gradual reduction across the FT3 tertile groups (59.6%, 46.4%, and 38.6%, p < 0.01) in type 2 diabetes with euthyroid function, and FT3 levels were negatively correlated with urinary albumin-to-creatinine ratio after adjustment for various risk factors according to multiple linear regression analysis.…”

Dysregulation Serum miR-19a-3p is a Diagnostic Biomarker for Asymptomatic Carotid Artery Stenosis and a Promising Predictor of Cerebral Ischemia Events

“…4 However, current imaging has different deficiencies in the diagnosis of moderate stenosis (>50%) or severe stenosis (>70%) in asymptomatic CAS patients. For example, the preferred noninvasive diagnosis method of CAS in clinical practice is duplex ultrasound imaging, which is simple and safe, but it is easily affected by the level of operators, and it is expensive and not suitable for large-scale screening of the population [5][6][7] Therefore, the current priority is to identify and treat asymptomatic CAS patients as early as possible through noninvasive and low-cost methods to reduce the risk of stroke.…”

Association of Thyroid Hormone Levels with Microvascular Complications in Euthyroid Type 2 Diabetes Mellitus Patients

“…In addition, our previous study found that the low-normal FT3 and FT4 levels are associated with macrovascular complications in euthyroid type 2 diabetes mellitus patients. 17 However, the relationship between thyroid hormone and diabetic microvascular complications remains unclear. Therefore, to provide more comprehensive information for future research, we performed the present study to analyze the association of thyroid hormone with individual and any form of diabetic microvascular complications in euthyroid T2DM patients in the same population.…”