A comparative study of thyroid stimulating hormone among lean and obese women with polycystic ovarian syndrome

Background: The polycystic ovarian syndrome (PCOS) is an abnormality of young women of reproductive age. Between 20-50% of women with PCOS are normal weight or thin, and the pathophysiology of the disorder in these women may be related to a hypothalamic-pituitary defect that results in increased release of LH. PCOS and Thyroid disorders share certain common characteristics, risk factors, and pathophysiological abnormalities. In this study we have compared the serum TSH levels in obese and non-obese PCOS women to detect if there is a significant difference in the occurrence of hypothyroidism based on the BMI.Methods: Non-pregnant women attending the gynecological OPD diagnosed with PCOS as per Rotterdam criteria were included. Serum TSH was done in all women diagnosed as PCOS and based on their BMI women were either included in obese or non-obese group using Asian cut-off for BMI and the values compared.Results: In the present study 152 women were included. Women with low BMI and normal BMI were grouped as lean PCOS or non-obese PCOS and the overweight and obese women together were grouped as obese PCOS. The total number in the lean group was 28 and 124 in the obese group. Raised serum TSH levels were observed in 23.02%(35) women out of which 17.14%(6) belonged to the non-obese group and the remaining 82.85%(29) to the obese group. Among the 152 women thyroid enlargement was seen in 1.3%(2). Both women had raised serum TSH levels and both belonged to the obese group.Conclusions: The results of our study seem to indicate that thyroid dysfunction in PCOS women developed irrespective of presence or absence of obesity.

Screening of Subclinical Hypothyroidism and Glycosylated Hemoglobin Levels in Healthy Subjects Attending Rural Tertiary Care Centre in Western U.P. (Hapur)

Background: Subclinical hypothyroidism is defined as an elevated serum TSH level and normal concentrations of free T3 (FT3), free T4 (FT4), T3 and T4. A positive association between thyroid and diabetes mellitus is well recognized but to study the effect of thyroid disorders on glucose metabolism in non-diabetic patients is an area for extensive research. Present study was planned to assess correlation between subclinical hypothyroidism and glycosylated hemoglobin levels in non-diabetic patients. Methods: A case-control study was conducted on total 209 subjects. 109 patients were allotted in case group and 100 in control group. Controls were relatives and friends of patients who were matched for age and sex. Comparison between the case and the control groups were made using Student’s t-test (unpaired) and Box and Whisker Plot and regression graph were presented for correlation between serum TSH and HbA1c. Results: It was found that there was a positive correlation between the levels of serum TSH (µU/L) and HbA1c (%) in all the participants of the study by Pearson’s correlation coefficient (r=0.35, p < 0.0001). Conclusion: HbA1c levels are increased in subclinical hypothyroid patients. The effects of the elevated levels of Serum TSH on the HbA1c must be considered when interpreting the HbA1c for the diagnosis of diabetes or prediabetes in the subclinical hypothyroid patients.

Serum TSH level stability after 5 years in euthyroid adults at low risk for thyroid dysfunction

ABSTRACT Objective: To evaluate changes in thyroid function after 5 years, the interval proposed for new assessment, in initially euthyroid adults. Subjects and methods: Initially, 1,426 apparently healthy adults considered low risk for thyroid dysfunction, were evaluated by measurement of TSH. After 5 years, 1,215 (85.2%) subjects were reevaluated. Results: After 5 years, four subjects were receiving levothyroxine (L-T4) replacement therapy and 25 others had TSH > 4 mIU/L, only two of them with TSH > 10 mIU/L. All of these subjects had TSH > 3 mIU/L in the initial evaluation. During reassessment, none of the subjects had been or was treated for hyperthyroidism and 22 had TSH < 0.4 mIU/L (none of them < 0.1 mIU/L). Nineteen of these subjects had TSH ≤ 0.6 mIU/L in the initial evaluation. Among the 1,098 subjects with TSH between 0.6 and 3 mIU/L in the initial evaluation, reassessment showed that none of the subjects was using L-T4; only three had TSH > 4 mIU/L (none of them > 10 mIU/L); none had been or was treated for hyperthyroidism, and only three had TSH < 0.4 mIU/L (none of them < 0.1 mIU/L). These results did not differ between men and women or between subjects ≤ 60 and > 60 years. Conclusion: Repeat TSH measurement within an interval of only 5 years would not be cost-effective in adults without known thyroid disease or risk factors for dysfunction who exhibit TSH between 0.6 and 3 mIU/L.

Serum Thyroglobulin Varies according to Thyrotropin Levels during Preparation for Treatment by Radioactive Iodine Ablation and Scan / 대한내분비외과학회지

PURPOSE: Periods of L-T4 withdrawal and low iodine diet, which are required prior to the treatment and tracking tests that take place after a thyroidectomy, can be of a long duration and cause suffering for patients. The purpose of this study, conducted in South Korea, was to confirm if periods of L-T4 withdrawal and low iodine diet can be shortened by using TSH level prediction. By inquiring into the correlation between TSH level and serum Tg level, and measurement of the amount of iodine present in urine during the low iodine diet period, a thyroglobulin (Tg) cutoff level can be predicted. METHODS: total of 168 patients were included as research subjects. In each case, L-T4 was suspended 3-4 weeks prior to conducting radioactive iodine ablation and 131I scan, and then a low iodine diet was carried out for 2-4 weeks. Serum TSH, Tg and anti-Tg antibodies were measured on the second week of L-T4 withdrawal, and the spot urine Iodine/Creatinine ratio was measured on the second and fourth week after treatment. RESULTS: Three weeks after L-T4 withdrawal, TSH levels increased to over 30μIU/ml in 97.2% of the patients, and serum thyroglobulin levels also increased with TSH level to over 30μIU/ml. There was no measured difference in the amount of iodine in the subject's urine during the low iodine diet period. CONCLUSION: It was found that L-T4 withdrawal can be reduced to 3 weeks or less, and that the Tg cutoff level differs according to TSH level. Based on these results, we suggested that the low iodine diet period can be reduced to 1-2 weeks.

Insulin Like Growth Factor-I and Insulin Like Growth Factor Binding Protein-3 in Human Thyroid Cystic Fluids / 대한내분비학회지

In the thyroid tissue, thyrotrophin(TSH) and IGF-I played major role of the goitrogen. But the evidences and precise mechanism of these two factors were not known so much. Actually local secretion of thyroid IGF-I was originated from its fibroblasts mainly. We guessed major roles of IGFs in the thyroid tissue were local paracrine effect of thyroid cells proliferation and differentiation which concert with TSH. Recently, some reporters described the source of thyroid IGF-I were partly from thyroid follicular cells and its action were synergistic with TSH. We measured TSH, IGF-I and IGFBP-3 from sera and thyroid cystic fluids in 36 patients with simple thyroid cyst and examined into correlation between TSH, IGF-I and IGFBP-3.1) According to cyst/serum TSH ratio, we classified two groups(Group I; c/s TSH 1, n=17). This classification criteria means that cystic TSH level were increased than that of serum or not.2) The serum TSH, IGF-I and IGFBP-3 levels are not difference between group I and II.3) Cystic TSH were dependent on the serum TSH in Group I, but negative correlation in Group II. In Group II, cystic TSH was significant increased.4) Serum IGF-I were positive correlation in each Group5) In Group II, cystic IGF-I was not exceed than those of serum IGF-I, but some cystic IGFBP-3 were more increased than those of serum.6) In Group II, cystic IGFBP-3 increased than serum TSH, and cystic IGFBP-3 was positive correlation with cystic TSH and cystic IGF-I.As these data suggested that cystic TSH and cystic IGF-I levels may influence cystic IGFBP-3 level. The main effect for maintenance of cyst was mediated by cystic TSH and cystic IGFBP-3. But the cystic IGFBP-3 has major role for thyroid cyst than cyst TSH.