Relation between thyroid volume and carotis intima media thickness in patients with newly diagnosed diabetes and prediabetes

Diabetes mellitus, whose basic pathophysiology is hyperglycemia, is a common endocrine disease characterized with defect in carbohydrate, fat and protein metabolism due to insufficiency in insulin secretion or effect. Since the risk for cardiovascular and cerebrovascular diseases increases in diabetes, early diagnosis and therapy in individuals with a risk for diabetes is crucial in decreasing mortality and morbidity. As carotis intima media thickness is an indirect marker of coronary artery atherosclerosis, recent studies have been focusing on this topic, showing that insulin resistance has a volume-increasing effect on the thyroid. Insulin causes morphological changes in the thyroid tissue by reproducing thyrocytes via IGF-1 dependent mechanisms. It has been shown that the thyroid volume and carotis intima media thickness was increased in diabetic patients compared to healthy individuals. In this study, we aimed to compare the relation between carotis intima media thickness and thyroid volume in patients with newly diagnosed diabetes and prediabetes. In our study, prediabetes and diabetes was analyzed in patients with known diabetes mellitus and no thyroid disease that applied to the internal medicine polyclinic at the Erzincan Binali Yildirim University Medical School Hospital. A total of three groups were established: newly diagnosed diabetes, prediabetes, and control group. 36 male and 35 female patients with newly diagnosed diabetes, 36 VI male and 35 female patients with prediabetes, and 36 male and 35 female patients for the control group (totally 213 patients) were included to the study. Among patient groups included to the study, parameters including, waist/hip ratio (a ratio containing markers of cardiovascular risk parameters/markers), serum uric acid level, fasting glucose, fasting insulin, insulin resistance, carotis intima media thickness were evaluated. In the diabetes and prediabetes group, HDL-cholesterol levels were lower; uric acid, total cholesterol, LDL cholesterol values were higher compared to the control group. In the intergroup comparison, there was a statistically significant difference between waist circumference, waist/hip ratio, systolic and diastolic blood pressure, HbA1c, triglyceride, left/right and total thyroid volume, and fasting insulin and insulin resistance. There was a statistically significant relation between insulin resistance and thyroid volume and carotis intima media thickness. According to these results, it may be concluded that atherosclerosis may occur at the stage of hiperinsulinemia, insulin resistance and prediabetes, even before the development of diabetes. Early therapy in prediabetes may be a effective approach in both preventing and postponing diabetes development, and decreasing cardiovascular morbidity and mortality rates. Measurement of carotis intima media thickness and thyroid volume could be useful in determining cardiovascular risks due to being inexpensive, accessible and noninvasive. Further large-scale studies are needed on this topic. Keywords: Diabetes Mellitus, Prediabetic State, Insulin Resistance, Thyroid Gland, Carotis Intima-Media Thickness