A Case of New-onset Autoimmune Type-1 Diabetes Mellitus Following COVID-19 Infection.

BACKGROUND: After COVID-19 infection, various mechanisms may initiate an increased risk of developing DM. This study presented a newly developed autoimmune Type 1 DM (T1DM) case in an adult patient after a SARS-CoV-2 infection. CASE PRESENTATION: A 48-year-old male patient presented with complaints of weight loss and blurred vision. His blood sugar and HbA1c were measured as 557 mg/dl and 12.6%, respectively. His medical records showed no known diagnosis of DM. He had a SARS-CoV-2 infection 4 weeks ago. Then, we diagnosed DM and started basal-bolus insulin therapy. C-peptides and autoantibodies were requested from the patient to explore the etiology of diabetes. Glutamic acid decarboxylase (GAD) antibody was > 2000 U/mL (ref: 0-10); therefore, the patient was accepted as having autoimmune T1DM. New-onset DM cases triggered by COVID-19 have increasingly been reported recently. SARS-CoV-2 virus, using the ACE2 receptor in the pancreas, can enter beta cells and causes damage to these islets and impaired insulin secretion, leading to acute diabetes mellitus. In addition, the abnormal immunity elicited by SARS-CoV-2 can also induce autoimmune destruction of pancreatic islet cells. CONCLUSION: T1DM may be an uncommon but possible complication due to the COVID-19 virus among genetically predisposed individuals. Overall, the case highlights the importance of preventive measures, such as vaccination, to protect against COVID-19 and its complications.

The Experience of our Center in Patients Undergoing Insulin Degludec/ Insulin Aspart Co-formulation Therapy.

AIM: A co-formulation containing insulin degludec and insulin aspart (IDegAsp) is available for the treatment of diabetes in Turkey. We aimed to evaluate the clinical results of switching to IDegAsp treatment for Type 2 diabetes. METHODS: A total of 217 patients with type 2 diabetes treated with IDegAsp and having follow-up data were included. The patients were divided into 3 groups. Group 1 switched from basal insulin to IDegAsp, group 2 switched from twice-daily premixed insulin regimen to IDegAsp, and group 3 switched from intensive and thrice-daily premixed insulin regimen to IDegAsp. Groups were evaluated in terms of changes in insulin dose, the number of injections, and changes in HbA1c. RESULTS: The mean follow-up period was 7.5 ± 4.4 months. The mean age was 62.8 ± 12.9 years. The mean duration of diabetes was 15.3 ± 8 years. There was a significant decrease in HbA1c and glucose (p < 0.0001 and p < 0.0001, respectively). HbA1c was significantly reduced in group 1 (p < 0.0001) while insulin dose and the number of injections increased (p < 0.0001 and p < 0.0001, respectively). HbA1c, insulin dose, and the number of injections in group 2 and group 3 (p = 0.001, p = 0.002, p < 0.0001, respectively, and p < 0.0001, p = 0.043, p < 0.0001, respectively) were significantly reduced. CONCLUSION: This study includes real-life experiences involving a remarkable number of patients in the literature. IDegAsp treatment provided effective blood glucose regulation and caused a significant decrease in the insulin dose and the number of injections, resulting in increased quality of life among those who had to receive twice or more insulin injections.

A Case Report of Concurrent Graves' Disease and Subacute Thyroiditis Following SARS-CoV-2 Vaccination: An Autoimmune/Inflammatory Syndrome (ASIA).

BACKGROUND: The response against adjuvants in vaccines is presented as autoimmune/inflammatory syndrome (ASIA). In this case report, we presented both SAT and Graves' disease in a patient as ASIA following the BNT162b2 mRNA COVID-19 vaccination. CASE PRESENTATION: A 31-year-old woman was admitted to the endocrinology outpatient clinic with the complaint of neck pain following the second dose of the BNT162B2 SARS-CoV-2 (Pfizer/BioNTech) vaccine. On physical examination, her thyroid gland was tender on palpation. Her thyroid function tests were compatible with hyperthyroidism, and inflammatory markers were high. In the thyroid ultrasonography (US) examination, we observed bilateral diffuse hypoechoic areas in the thyroid gland and increased vascularity in some parts of the thyroid. Anti-thyroid stimulating hormone receptor antibodies (TRAB) were positive. Overall, we considered concurrent subacute thyroiditis (SAT) and Graves' disease. CONCLUSION: The present study may be the first report to evaluate SAT and Graves' disease as ASIA following mRNA COVID-19 vaccination. Clinicians should be aware of possible vaccine-related complications.

A Case Report of Conversion from Hashimoto's Thyroiditis to Graves' Disease in Type 1 Diabetic Patient Following the COVID-19 Vaccination.

BACKGROUND: A considerable number of COVID-19 vaccines became available following the outbreak. Yet, various inflammatory and autoimmune complications have been reported following vaccination. We aimed to report the case of a type 1 diabetic patient converting from Hashimoto's thyroiditis to Graves' disease after the fourth dose of COVID-19 vaccine, thought to trigger an autoimmune/inflammatory syndrome induced by adjuvants (ASIA syndrome). CASE PRESENTATION: A thirty-one-year-old female patient with type 1 diabetes and Hashimoto's thyroiditis applied to our clinic with complaints of palpitations, anxiety, and weight loss one month after the fourth dose of COVID-19 vaccine (2 doses of CoronaVac + 2 doses of Pfizer/BioNTech). She was receiving levothyroxine 50 mcg/day. When her thyroid function tests showed thyrotoxicosis, we initially considered thyroxine-related exogenous thyrotoxicosis. However, we considered Graves' disease upon persisting thyrotoxicosis despite thyroxine withdrawal, positive serum TSH receptor antibody titers, and other imaging findings. Therefore, various autoimmune and inflammatory events have been reported after the COVID-19 vaccination. Adjuvants in vaccines can trigger autoimmune events, which lead to ASIA syndrome. COVID-19 vaccines may cause increased TSH receptor antibody levels or change the balance in the activity of blocking and stimulating antibodies, which may cause a conversion from Hashimoto's to Graves' disease. CONCLUSION: This was the first case report where the patient experienced a conversion from Hashimoto's to Graves' disease after COVID-19 vaccination, which may ultimately be related to ASIA syndrome. Yet, more data is needed to elucidate such a relationship, and patients should closely be checked regularly after four doses of vaccination.

Menstrual Changes after COVID-19 Infection and COVID-19 Vaccination.

Background: Several factors such as stress, depression, infection, and vaccination influenced the menstrual cycle in women during the coronavirus disease 2019 (COVID-19) pandemic. We investigated whether there were changes in the menstrual cycle in women after COVID-19 vaccination or infection and, if so, the nature of the change. Methods: This study was designed as a descriptive, cross-sectional study. A face-to-face survey was conducted among menstruating women aged 18-50 years from May 31 to July 31, 2022. Women were inquired about their first three menstrual cycles that occurred after COVID-19 infection or vaccination. Results: Of 241 women with COVID-19 infection, 86 (35.7%) mentioned that they experienced various changes in their menstrual patterns in the first three cycles after infection. Of 537 participants who received various COVID-19 vaccines, 82 (15.1%) stated that they experienced changes in their menstrual patterns after vaccination. The incidence of postvaccination menstrual change was higher in women who received Pfizer-BioNTech and Sinovac (CoronaVac) vaccines. Only 10.9% of women who reported a change in their menstrual pattern after vaccination or infection consulted a physician. Conclusion: COVID-19 infection and vaccination can affect the menstrual cycle in women. It is important to be aware of the menstrual changes after COVID-19 infection and vaccination and to warn and inform women about this issue.

Acoustic Radiation Force Impulse Elastography and Ultrasonographic Findings of Achilles Tendon in Patients With and Without Diabetic Peripheral Neuropathy: A Cross-Sectional Study.

AIMS: We aimed to evaluate the elastographic features of Achilles tendon with Acoustic Radiation Force Impulse in patients with and without diabetic neuropathy. METHODS: According to the presence of peripheral neuropathy, 45 patients with type 2 diabetes were divided into 2 subgroups. Those with peripheral neuropathy were defined as group I (22 patients) and those without peripheral neuropathy were defined as group II (23 patients). A total of thirty age-, gender-, and body mass index-matched healthy individuals were selected as controls. All participants underwent both ultrasonographic and Acoustic Radiation Force Impulse elastographic examination in order to evaluate Achilles Tendon thickness and stiffness. RESULTS: Achilles tendon thicknesses were similar between groups (p=0.991). Achilles tendon thicknesses of both patient groups were significantly higher than the control group (group I vs control p=0.01; group II vs control p=0.006). Stiffness values of Achilles tendons were similar between the control group and group II (p=0.993). Shear Wave Velocity was significantly lower in group I than group IIand control group (p<0.001). CONCLUSION: Diabetic patients with neuropathy have thicker and softer Achilles tendon while the elasticity of Achilles tendon in diabetic patients without neuropathy is similar to the healthy controls. Softening of the Achilles tendon may be an early sign of diabetic foot and reveal the patients with a risk of diabetic foot.

The effect of iatrogenic subclinical hyperthyroidism on anxiety, depression and quality of life in differentiated thyroid carcinoma

Background/aim: Overt thyroidism is known to cause neuropsychiatric disorders but studies on subclinical hyperthyroidism (SCH) are limited. Subclinical hyperthyroidism induction by administering L-Thyroxine (LT4) is the standard treatment method in differentiated thyroid carcinoma (DTC) follow-up. Our aim was to investigate whether anxiety, depression and quality of life are affected in DTC patients followed-up with exogenous SCH. Materials and methods: The patients were divided into exogenous SCH by LT4-DTC (n = 127), euthyroid-DTC (n = 66) and exogenous euthyroid-benign thyroid noduüle (BTN) who underwent thyroidectomy for benign thyroid pathology (n = 85) groups. Results: The rate of moderate/severe anxiety was significantly higher in SCH-DTC than euthyroid-BTN group (27.5%, n = 35 vs. 9.4%, n = 8) (P = 0.001). TSH levels and Beck anxiety inventory (BAI) scores were significantly negatively correlated(P = 0.009 r = ­0.16). Free T4 and BAI were significantly positively correlated (P = 0.04 r = 0.4). The groups were similar in terms of depression severity (P = 0.15). Subclinical hyperthyroid-DTC group scored significantly lowerthan euthyroid-BTN group in all scales of SF-36 quality of life survey. Conclusion: LT4-induced SCH, which is a part of traditional DTC treatment, can exacerbate the anxiety symptoms in patients and disrupt their quality of life, depending on the level of fT4.

Short-Term Effect of Hypergastrinemia Following Esomeprazole Treatment On Well-Controlled Type 2 Diabetes Mellitus: A Prospective Study.

OBJECTIVE: Proton pump inhibitor (PPI) drugs reduce gastric acid secretion and lead to an increase in serum gastrin levels. Many preclinical and some clinical researches have established some positive effects of gastrin or PPI therapy on glucose regulation. The aim of this study was to prospectively investigate the short term effects of esomeprazole on glycaemic control in patients with type 2 diabetes mellitus. In addition, the presence of an association between this effect and gastrin levels was evaluated. METHODS: Thirty-two subjects with type 2 diabetes mellitus were enrolled and grouped as intervention (n=16) and control (n=16). The participants in the intervention group were prescribed 40 mg of esomeprazole treatment for three months. At the beginning of the study and at the 3rd month, HbA1c level (%) and gastrin levels (pmol/L) of participants were assessed. Then, the groups were compared in terms of their baseline and 3rd month values. RESULTS: In the intervention group, the mean gastrin level increased significantly from 34.3±14.4 pmol/L to 87.4±43.6 pmol/L (p<0.001). The mean HbA1c level was similar to the pre-treatment level (6.3±0.7% vs. 6.4±0.9%, p=0.441). There were no statistically significant differences in all parameters of the control group. The majority of individuals were on metformin monotherapy (65.6 %). The subgroup analysis of metformin monotherapy revealed that, in intervention group, there was a significant increase in gastrin levels (39.9±12.6 vs. 95.5±52.5, p=0.026), but the HbA1c levels did not change (6.0±0.4 % vs. 5.9±0.6 %, p=0.288); and in control group, gastrin levels did not change (37.5 ± 26.7 vs. 36.1 ±23.3, p=0.367), but there was an increase in HbA1c levels (6.1 ± 0.50 vs. 6.4 ± 0.60, p=0.01). CONCLUSION: Our study demonstrates that esomeprazole has no extra benefit for the controlled diabetic patient in three months. However, in only the metformin-treated subgroup, esomeprazole may prevent the rise in HbA1c level.

Unusual Long Survival with a Giant Invasive Pheochromocytoma of an Incompatible Patient.

Pheochromocytomas (PHEOs) are rare neuroendocrine tumors and about 2-13% of PHEOs are malignant. Predicting malignancy in PHEO cases with invasion but without metastasis is still controversial in the literature. This study presents an unusual long survival with a giant invasive PHEO in an incompatible patient and a review of the literature. In 1989, a 23-year-old female patient was operated for a giant adrenal mass with a pathological final diagnosis of PHEO. Information to the patient's family was provided about the short life span of the patient in the postoperative period because the tumor could not be totally resected. The patient started using regular antihypertensive drugs only after 1994. In 1994, 3700 mBq 131-I-metaiodobenzylguanidine (MIBG) treatment was given. Since then, no specific treatment was administered for PHEO due to patient incompatibility. She was diagnosed with type 2 diabetes mellitus at the age of 40 years and had a cerebrovascular accident due to hypertension at the age of 42. New abdominal computed tomography (CT) showed a right-sided 75 x 37 mm irregular and heterogeneous mass lesion extending inferiorly from the diaphragmatic crus level located in the right adrenal locus compatible with local recurrence. There was no I-123-MIBG uptake. She refused to have advanced workup and further treatment options. Malignant PHEOs reduce overall survival as a consequence of excessive catecholamine release, large tumor burden, and malignancy-related complications. Currently, the treatment of a malignant PHEO still has difficulties for both patients and doctors. Main treatment options for malignant PHEOs are primarily surgical excision. The effect of radionuclide therapy on survival time still remains to be determined. Efforts should be made to identify clinical, biochemical, and pathological criteria for malignancy and to develop new therapies in these patients with malignancy. The clinical course of malignant PHEOs is remarkably variable. Disease-specific survival rate changes from 58 to 88.1% at five years in the literature. Recent discoveries have enhanced new options for treatment, from radionuclide therapy and targeted molecular therapy to immunotherapy. A multidisciplinary approach is needed to individualize treatment in patients with malignant and invasive PHEO.

Do Statins Affect Thyroid Volume and Nodule Size in Patients with Hyperlipidemia in a Region with Mild-to-Moderate Iodine Deficiency? A Prospective Study.

OBJECTIVE: The objective of this study was to assess the antiproliferative pleiotropic effects of statins on thyroid function, volume, and nodularity. SUBJECTS AND METHODS: One hundred and six hyperlipidemic patients were included in this prospective study. The 69 patients in the statin groups received atorvastatin (16 received 10 mg and 18 received 20 mg) or rosuvastatin (20 received 10 mg and 15 received 20 mg). The 37 patients in the control group, assessed as not requiring drugs, made only lifestyle changes. Upon admission and after 6 months, all patients were evaluated by ultrasonography as well as for lipid variables (total cholesterol, high- and low-density lipoprotein cholesterol, and triglycerides) and thyroid function and structure. RESULTS: After 6 months, no differences in thyroid function, thyroid volume, the number of thyroid nodules, or nodule size were observed in the statin and control groups. In a subgroup analysis, total thyroid volume had decreased more in patients receiving 20 mg of rosuvastatin than that in the control group (p < 0.05). Maximum nodule size had decreased more in those receiving 10 mg of rosuvastatin (p < 0.05). CONCLUSIONS: Our results suggest an association between rosuvastatin treatment and smaller thyroid volume and maximum nodule diameter; this could be attributable to the antiproliferative effects of statin therapy on the thyroid.

Metformin Decreases Thyroid Volume and Nodule Size in Subjects with Insulin Resistance: A Preliminary Study.

OBJECTIVE: The aim of this study was to investigate the effects of metformin on thyroid volume and nodule size. SUBJECTS AND METHODS: Prospective data were gathered on 100 newly diagnosed subjects with insulin resistance (68 female, 32 male) between August 2008 and May 2010. Each subject followed a standard diet and exercise program, and received 1,700 mg/day of metformin therapy for 6 months. The height, weight, waist circumference (WC) and thyroid hormone levels of each subject were measured. Additionally, the dimensions of the thyroid lobes and maximum diameter of each thyroid nodule were determined by ultrasonography. BMI and thyroid volumes were also calculated. Insulin resistance was estimated by homeostasis model assessment. All these parameters were measured at the beginning and at the end of the treatment period. RESULTS: BMI and WC decreased significantly after metformin therapy (34.5 ± 5.1 vs. 32.7 ± 4.8, p < 0.0001, and 106.3 ± 11.8 vs. 101.8 ± 19.0 cm, p = 0.008, respectively). Insulin resistance also decreased after metformin therapy (4.5 ± 1.9 vs. 2.9 ± 1.7, p < 0.0001). The mean thyroid volume (22.5 ± 11.2 vs. 20.3 ± 10.4 ml, p < 0.0001) and mean thyroid nodule size (12.9 ± 7.6 vs. 11.7 ± 7.2 mm, p < 0.0001) also decreased after treatment. CONCLUSION: In subjects with insulin resistance, metformin therapy significantly decreased thyroid volume and nodule size.

Thyroid volume in patients with glucose metabolism disorders.

OBJECTIVE: Thyroid volume and the prevalence of thyroid nodules are higher in patients with insulin resistance. A relationship between thyroid volume and glucose metabolism disorders (GMD) has not as yet been clarified. The present retrospective study aimed to investigate the association between GMD and thyroid volume. SUBJECTS AND METHODS: We investigated the data of 2,630 patients who were evaluated for thyroid biopsy in our hospital. The study population included 602 patients with GMD, 554 patients with diabetes mellitus (DM) and 1,474 patients with normal glucose metabolism as a control group. We obtained the levels of serum thyroid stimulating hormone (TSH) and the thyroid volumes of those patients retrospectively. RESULTS: The median ages for the control group, GMD group and DM group were 55 (15-91) years, 60 (27-97) years, and 65 (27-91) years respectively and there was a statistically significant difference between the groups with regard to age and gender (p<0.001). Levels of TSH were similar in all groups. The median total thyroid volumes for patients with DM and GMD were significantly higher than that of the control group [22.5 (3-202) mL, 20.2 (4-190) mL, and 19.2 (3-168) mL respectively, p≤0.001 for all parameters]. Also the median total thyroid volume for patients with DM was significantly higher than that of the GMD group (p<0.001). According to the correlation analysis, thyroid volume was significantly correlated with age (r=0.92, p<0.001) and TSH (r=0.435, p<0.001). Age, gender, TSH levels, GMD and DM diagnosis were independently correlated with thyroid volume. CONCLUSION: The thyroid gland is one of the target tissues of metabolic disorders. We reported a positive correlation between GMD/type 2 DM and thyroid volume. Further controlled, prospective, randomized studies on this subject are required to gain more information.

The relationship between thyroid volume and malignant thyroid disease.

The present retrospective study aimed to investigate the relationship between thyroid volume and prevalence of thyroid cancer. We investigated the data of 3,850 patients who underwent fine-needle aspiration biopsy (FNAB). Biopsy results were evaluated as diagnostic or nondiagnostic, and diagnostic results were classified as benign, malignant, and indeterminate. We included 2,672 patients who underwent FNAB firstly in our hospital and evaluated as diagnostic biopsy except subgroup of indeterminate. We obtained cytologic data, levels of serum thyroid-stimulating hormone (TSH), and thyroid volumes of those patients retrospectively. Among 2,672 patients with thyroid nodule, 2,562 (95.9 %) patients had benign cytology and 110 (%4,1) patients had malignant cytology. There was no correlation between the malignancy and gender (p = 0.935), and patients with malignant cytology were younger (52 vs 59, p < 0.001). Also, TSH levels were higher in patients with malignant than benign cytology (p = 0.017). Median volume of right part, left part, and total thyroid for patients who had malignant cytology was significantly lower than patients who had benign cytology (8.3, 7.1, 15.9 vs 10.8 ml, 9.0 mml, 20.6 ml, respectively, p ≤ 0.001 for all parameters). The results demonstrated that thyroid cancer prevalence was higher in patients with low thyroid volume. According to our results, thyroid volume should be considered as a risk factor for malignancy in the evaluation of thyroid nodules.

The relationship between glucose metabolism disorders and malignant thyroid disease.

BACKGROUND: Previous studies have shown a positive relationship between insulin resistance and several common adult cancers. The present retrospective study aimed to investigate the association between glucose metabolism disorders (GMDs) and the prevalence of thyroid cancer. METHODS: We investigated the data of 4272 patients who had undergone fine-needle aspiration biopsy (FNAB) of thyroid nodules. The biopsy results were evaluated as diagnostic or non-diagnostic and the diagnostic results were classified as benign, malignant, and indeterminate. In this study, we included 2234 of the above patients who had undergone FNAB at our hospital and whose biopsy results were evaluated as diagnostic and were classified as either benign or malignant. We obtained the cytologic data and the glucose metabolism status of these patients retrospectively. RESULTS: Of the 2234 patients, 629 (28.1 %) had GMD (impaired fasting glucose, impaired glucose tolerance). Malignant cytology was determined in 106 (4.7 %) patients overall. Of the 629 patients with GMD, 582 (92.5 %) patients had benign cytology and 47 (7.5 %) patients had malignant cytology. Fifty-nine (3.7 %) of the 1605 normoglycemic patients had malignant cytology. Malignant cytology was determined more frequently in the patients who had GMDs (p < 0.001). CONCLUSION: The results demonstrated that thyroid cancer prevalence was higher in patients with GMD. According to our results, GMD should be considered as a risk factor for malignancy in the evaluation of thyroid nodules.

Cyclin A and cyclin B1 overexpression in differentiated thyroid carcinoma.

Approximately 30% of patients with thyroid nodules have indeterminate or suspicious fine-needle aspiration (FNA) biopsy results. These patients usually undergo thyroidectomy because of cancer risk. Our aim was to determine diagnostic value of cyclin A and cyclin B1 immunohistochemistry added to routine cytology and their expression on histological sections. We studied the expression of cyclin A and cyclin B1 in FNA biopsies and resection specimens of 168 indeterminate or suspicious FNA biopsy results retrospectively at an academic hospital using immunohistochemistry. Malignant histopathology consisted 64 of resection specimens (58 papillary, 4 follicular, 1 medullary, and 1 Hürthle cell carcinoma). Cyclin A was overexpressed in 51.5% of malignant cases in contrast to 31.7% of 104 benign pathology specimens (P = 0.025). Cyclin B1 was positive in 39.1% of malignant specimens in contrast to 15.4% of benign cases (P = 0.001). Cyclin A overexpression was not linked to cyclin B1 overexpression. No association was found between overexpression of cyclin A, cyclin B1 and age, thyroiditis, multifocality, tumor size, extra-thyroidal extension, capsule infiltration, lymph node and distant organ metastases and TNM stage in malignant cases. Female patients with thyroid carcinoma overexpressed significantly more cyclin B1 than male patients (P = 0.015). Retrospective analysis of cyclin A and cyclin B1 in FNA biopsies yielded negative results for both benign and malignant cases. In conclusion, cyclin A and cyclin B1 are useful markers in the distinction of benign and malignant thyroid tumors and can increase diagnostic accuracy.

Effects of bilateral ovariectomy and estrogen replacement therapy on serum leptin, sex hormone binding globulin and insulin like growth factor-I levels.

Studies evaluating the effect of estrogen replacement therapy (ERT) on leptin levels are contradictory. The aim of this study was to investigate effects of bilateral ovariectomy and ERT on serum leptin levels and anthropometric measurements as well as interaction among leptin, sex hormone binding globulin (SHBG), and insulin like growth factor-I (IGF-I) in premenopausal women after bilateral ovariectomy. Twenty-four premenopausal women who undergo bilateral overiectomy were divided into two groups based on whether they received hormonal treatment postoperatively. The studied parameters were evaluated in both groups preoperatively and during the fourth and eighth weeks postoperatively. Serum leptin, testosterone, prolactin, insulin, IGF-1 levels, BMI, HOMA-IR, and waist-to-hip ratio values did not change in both groups at all times. In the estradiol group, serum SHBG concentrations were significantly higher on weeks 8 compared with control group and basal values (p = 0.03 and 0.014, respectively). Leptin levels showed a positive linear correlation with BMI in all groups and at all times evaluated (r = 0.80, p < 0.01 for controls and r = 0.62, p < 0.01 for women treated with 17beta-estradiol) and with insulin in estradiol group on weeks 4 (r = 0.755, p < 0.05). No correlation was found between leptin and estradiol, testosterone, prolactin, SHBG, IGF-1 levels, and anthropometric variables at all times. Leptin levels do not show modification 8 weeks after bilateral ovariectomy and under ERT, suggesting that estrogens do not have a stimulatory action on leptin in humans. Although needing confirmation by a longer study, our findings suggest that IGF-I system and SHBG did not regulate leptin and vice versa and ERT do not have any effect on leptin, SHBG, and IGF-I.

Metabolic syndrome and its components are associated with increased thyroid volume and nodule prevalence in a mild-to-moderate iodine-deficient area.

OBJECTIVE: Metabolic syndrome (MetS) is a cluster of metabolic abnormalities with insulin resistance (IR) as a major component. It has been recently questioned whether MetS and its related components are associated with functional and morphological alterations of the thyroid gland. The aim of our study is to examine thyroid volume and nodule prevalence in a case-control study of patients with MetS in a mild-to-moderate iodine-deficient area. DESIGN: Two hundred and seventy-eight patients with MetS were randomly matched for age, gender, and smoking habits with 261 subjects without MetS. Serum TSH, free tri-iodothyronine and thyroxine, and the level of IR, which was estimated by the homeostasis model assessment for IR, as well as other MetS parameters were evaluated. Thyroid ultrasonography was performed in all subjects. All subjects with thyroid nodules >1 cm were offered to undergo thyroid fine needle aspiration biopsy. RESULTS: TSH was significantly positively correlated with the presence of MetS diagnosis. There was no association between free thyroid hormone levels and MetS and its related components. Mean thyroid volume was significantly higher in patients with MetS than in controls (17.5 + or - 5.5 vs 12.2 + or - 4.2 ml, P<0.0001). Also the percentage of patients with thyroid nodules was significantly higher in patients with MetS (50.4 vs 14.6%, P<0.0001). Subjects were also divided into two groups according to the presence of IR. The group of subjects with IR had increased thyroid volume and nodule formation. The odds ratio for the development of thyroid nodule in the presence of IR was 3.2. TSH as well as all MetS components were found to be independent predictors for thyroid volume increase. IR but not TSH was found to be correlated with thyroid nodule formation. Thyroid cancer was diagnosed in 3 out of 38 patients with MetS who agreed to have a biopsy (7.9%). None of the subjects in the control group was diagnosed to have thyroid cancer. CONCLUSIONS: The results suggest that patients with MetS have significantly increased thyroid volume and nodule prevalence. Multivariate regression analysis model demonstrated that the presence of IR contributed substantially to this increased risk. Our data provide the first evidence that IR is an independent risk factor for nodule formation in an iodine-deficient environment.