---

Diabetes commonly is associated with CAD risk factors, in addition sub-optimal metabolic control of diabetes is associated with increased incidence of thyroid function disorders. In this study patients with diabetes type II who were referred to 5th Azar Hospital in Gorgan were assessed to find out the relationship between thyroid dysfunction and NIDDM in such patients in Gorgan. We studied 210 diabetic patients in hospital outpatient department. The blood pressure, height, weight, serum total Cholesterol, Triglycerides, fasting blood sugar, and glycosylated hemoglobin (HbA1c) were determined. The obesity (BMI>30) were seen in 35% of the subjects. Hypertension and hyperlipidemia were seen in 38 and 65 of our patients respectively. The observed disorders included goiter (30%), sub-clinical hypothyroidism (13%), clinical hypothyroidism (4%), and clinical hyperthyroidism (0.5%). The patients were divided into two groups according to HbA1c: Group 1 with HbA1c<8 and group II with HbA1c?8. A significant difference was observed in TSH serum concentration between group I and II (1.5±1.2 vs. 3.7±11.3 mu/l, P<0.05), whereas the concentration of T4 (10±11 vs. 11±8) and T3 (2.4±3.7 vs. 1.9±3.2) were not significantly different between the two groups. The mean concentration of HbA1c in patients with hypothyroidism was significantly higher than those that of non-hypothyroid subjects (11±2.5 vs. 9±2.5, P<0.005). A significant positive correlation was observed between HbA1c concentration and TSH levels (R=0.2, P<0.01). Our results confirm the association between thyroid dysfunction and uncontrolled diabetes mellitus. It has been recommended that the final diagnosis of thyroid function disorder in diabetic patients should be made after optimal metabolic status has been archived.

---

Background and Objective: Insulin resistance (IR) is common in hypothyroidism. IR is one of risk factors for cardiovascular disease. Insulin clamp is the gold standard method for evaluation of IR but it is not routine in clinical usage. The triglyceride- glucose (TyG) and homeostasis model assessment (HOMA) indices are non-invasive surrogate of IR. This study was done to determine the IR using the TyG and HOMA indices in hypothyroid patients.
Methods: This descriptive-analytic study was done on 23 hypothyroid patients including 15 overt and 8 subclinical hypothyroid patients. All patients were new cases and were matched for age, sex, and high. TSH, FT4, TG, LDL, FBS and fasting plasma insulin level were measured twice at time of diagnosis and after treatment and the changes of TyG and HOMA indices were recorded.
Results: In two groups IR based on HOMA was more than TyG index. IR in overt hypothyroidism based on HOMA index was more than two times in comparison with TyG index at the first time and more than three times (10:3) at the second time. IR in subclinical hypothyroidism based on HOMA index was more than four times in comparison with TyG index at the first time and more than three times (7:2) at the second time. A significant difference was found in IR based on HOMA before and after treatment (P<0.05). There were not any significant differences in IR indices of overt hypothyroidism group.
Conclusion: The eight weeks treatment of hypothyroidism and reducing TSH level is probably having no effect on HOMA and TyG in overt and subclinical hypothyroidism.

---

Background and Objective: Sodium levothyroxine is one of the common medicines used for treatment of hypothyroidism and thyroid cancer. The study was done to determine the effect of sodium levothyroxine on knee articular cartilage tidemark integrity, plateau tibia cartilage thickness (calcified and non-calcified) and liver enzymes in induced hypothyroidism rats.
Methods: In this experimental study, 50 adult female BALB/c mice, weighting 25-30 grams were randomly allocated into one control and four experimental groups. Animals in control did not receive any medicine. Animals in the second group were received different increasing doses of sodium levothyroxine daily for 8 weeks. Animals in the third group were received constantly high dose of levothyroxine daily for 8 weeks. In the fourth group, the animals became hypothyroid with propylthiouracil (PTU). In the fifth group, animals with hypothyroidism were received sodium levothyroxine by gavage same as group 2. After 8 weeks serum samples were taken to determine ALT, AST and ALP. The plateau tibia cartilage stained with hematoxylin-eosin. Histologic changes evaluated by light microscopy. Using a light microscope equipped with camera, the samples were photographed and using a computer equipped with axiovision software. Cartilage (calcified and non-calcified) thickness measured in micrometer. The integrity of tidemark line on hematoxylin-eosin staining also evaluated.
Results: The results of the present study showed separation, disruption and destruction in tidemark line in group 3 (the group with high dosage of sodium levothyroxine from the beginning of the treatment). The total cartilage and non-calcified part thickness in groups 3, 4, 5 were reduced and in group 3 showed significant reduction (P<0.05). Calcified cartilage thickness in all groups were reduced and in group 3 showed significant reduction (P<0.05). ALT level decreased in all groups compared to control group but only in the second and third groups, the decrease of ALT was significant (P<0.05). AST serum level in all groups significantly increased in compared to control group (P<0.05). ALP serum level in all groups increased compared to the control group, but this increase was significant only in the groups 4, 5.
Conclusion: Consumption of sodium levothyroxine with constantly high dose can cause severe alteration in knee joint cartilage in hypothyroidism rats.

---

Background and Objective: Hypothyroidism is a clinical syndrome resulting from a deficiency in thyroid hormone production. Despite achieving normalized thyroid-stimulating hormone (TSH) levels through levothyroxine (LT4) therapy, many patients continue to experience residual symptoms. This persistence raises questions regarding the adequacy of standard monotherapy and suggests that alternative treatments, such as combination therapy (LT4 and liothyronine [LT3]), may be more effective for certain individuals. This study was conducted to determine the prevalence of residual symptoms after TSH normalization in patients with hypothyroidism in Gorgan, Iran.
Methods: This descriptive-analytical study was conducted on 200 patients (193 females, 7 males; mean age = 41.81±12.25 years) with a confirmed diagnosis of hypothyroidism who were under regular treatment and had normalized TSH. Subjects were recruited from those referring to an endocrinology subspecialty clinic in 2022 in Gorgan. Eligible participants were asked to complete a checklist assessing common symptoms of hypothyroidism, including fatigue, dry skin, weight gain, cold intolerance, constipation, muscle cramps, facial puffiness, and hair loss. Paraclinical data, including TSH and thyroid peroxidase antibody (anti-TPO) levels, were also collected.
Results: The most prevalent residual symptoms of hypothyroidism were fatigue (74.2%), cold intolerance (73.7%), and dry skin (73.2%). A statistically significant correlation was found between body mass index (BMI) and dry skin (P<0.05). However, no significant correlation was observed between TSH levels and the persistence of symptoms.
Conclusion: Despite TSH normalization, symptoms of hypothyroidism-including fatigue, cold intolerance, and dry skin-persist in more than 70% of cases.