عملکرد تیروئید و ارتباط آن با مقاومت به انسولین در زنان مبتلا به دیابت بارداری در مقایسه با زنان باردار سالم

Background and Objective: Gestational diabetes and hypothyroidism in pregnancy are the most common endocrine disorders which are considered as insulin resistant conditions. Maternal thyroid hormones play an important role in embryogenesis, fetal maturity, and child’s IQ level. It seems that subclinical hypothyroidism in women with gestational diabetes has a higher prevalence. Since thyroid function tests during pregnancy are not considered as part of a routine testing, therefore, we aimed to study thyroid function associated with insulin resistance in pregnant women. Materials and Methods: In this descriptive-analytic study, 142 pregnant women were randomly entered in GDM and normal groups. After obtaining demographic data and measuring all patients’ BMI, Glucose Tolerance Test (GTT) was performed. Serum insulin, thyroid function test and anti –TPO antibody were measured on fasting blood samples. Data were analyzed using descriptive statistics, T-test, Chi-square test and multivariate regression analysis . Results: 68 pregnant women with GDM and 74 normal pregnant women participated in this study. Patients with GDM had higher age and BMI (P< 0.0001). After eliminating the confounding variables, no significant correlation was found between TSH and insulin or HOMA-IR. Elevated anti-TPO was seen in 14.7% of GDM and 6.8% of normal women (P= 0.171). Significant correlation of anti TPO level was found between both insulin level (P= 0.01) and HOMA-IR (P=0.03). Conclusion: This study did not show any association between thyroid dysfunction and GDM. However, a higher anti-TPO level was seen in GDM patients. Further investigations with more sample sizes are recommended. References 1- VelkoskaNakova V, Krstevska B, DimitrovskiCh, et al. Prevalence of thyroid dysfunction and autoimmunity in pregnant women with gestational diabetes and diabetes type. Source Medical Science Faculty. 2010 31: 51-9. 2- Burrow GN, Fisher DA, Larsen PR. Maternal and Fetal thyroid function. N Engl J Med. 1994 331(16): 1072. ٣- Gharib H, Tuttle RM, Baskin HJ, Fish LH, Singer PA, McDermott MT. Subclinical thyroid dysfunction: a joint statement on management from the American Association of Clinical Endocrinologists, the American Thyroid Association, and the Endocrine Society. Thyroid. 2005 15(1): 24-8. 4- Crowther CA, Hiller JE, Moss JR, McPhee AJ, Jeffries WS, Robinson JS. Effect of treatment of gestational diabetes mellitus on pregnancy outcomes. N Engl J Med. 2005 352(24): 2477-86. 5- Metzger BE, Gabbe SG, Persson B, et al. International Association of Diabetes and Pregnancy Study Groups Consensus Panel International association of diabetes and pregnancy study groups recommendations on the diagnosis and classification of hyperglycemia in pregnancy. Diabetes Care. 2010 33: 676-82. 6- Longo DL, Kasper DL, Jameson JL, Fauci AS, Stephen LH, Joseph L. Harrisons Principle of Internal Medicine .18 th ed. Vol 2.McGraw-Hill: New York 2011. 7- Surks MI, Hollowell JG. Age-specific distribution of serum thyrotropin and antithyroid antibodies in the US population: implications for the prevalence of subclinical hypothyroidism. J Clin Endocrinol Metab. 2007 92(12): 4575-82. 8- Olivieri A, Valensise H, Magnani F. et al. High frequency of anti thyroid autoantibodies in pregnant women at increased risk of gestational diabetes mellitus. Euro J Endocrinol. 143: 741-747. 9- Bech K, Hoier-Madsen M, Feldt-Rasmussen U, Jensen BM, Molsted-Pedersen L, Kuhl C. Thyroid function and autoimmune manifestations in insulin-dependent diabetes mellitus during and after pregnancy. ActaEndocrinologica. 124: 534-9. 10- Luísa R, Sandra P, Maria C, Elvira M, et al. Prevalence of thyroid antibodies in gestational diabetes mellitus. Endocrine Abstracts. 2007 14 P: 338. 11- Casey BM, Dashe JS, Wells CE, et al. Subclinical hypothyroidism and pregnancy outcomes. Obstet Gynecol. 2005 105(2): 239-45. 12- Emmy V, Rosa V, Jolande A, et al. Significance of subclinical thyroid dysfunction and thyroid autoimmunity before conception and in early pregnancy. a systematic review. Hum Reprod Update. 2011 17 (5): 605-19. 13- Mukesh M. Agarwal, Gurdeep S. et al. Thyroid function abnormalities and antithyroid antibody prevalence in pregnant women at high risk for gestational diabetes mellitus. Gynecological Endocrinol. 2006 22: 261-6. 14- Tuzcu A, Bahceci M, Gokalp D, Tuzun Y, Gunes K. Subclinical hypothyroidism may be associated with elevated high-sensitive hyperinsulinemia. J Endocrinol. 2005 52: 89-94. 15- Dimitriadis G, Mitrou P, Lambadiari V, et al. Insulin action in adipose tissue and muscle in hypothyroidism. J Clin Endocrinol Metab. 2006 91: 4930-4937. 16- Eirini M, Dimitrios JH, Anastasios K, et al. Studies of insulin resistance in patients with clinical and subclinical hypothyroidism. Euro J Endocrinol. 2009 160: 785-90. 17- Sheikholeslami H, ZIAEI AQ. A study of the relationship between diabetes and hypothyroidism. J Qazvin Univ Med Sci. 2007 11: 51-6. 18- Bazrafshan HR, Ramezani MA, Salehei A, et al. Thyroid dysfunction and its relation with diabetes mellitus (NIDDM). J Gorgan Uni Med Sci. 2000 2 (1): 5-11. 19- Karamifar H, Amirhakimi G. Goiter and hypothyroidism in children with insulin dependent diabetes mellitus. J Kashan Univ Med Sci. (FEYZ). 2004 7 (4): 95-100. 20- Dehghani Zahedani M, Azinfar A, Mahouri K, Mehrdad S. The identification of related risk factors of thyroid disorder in an iranian pregnant population. Iranian J Endocrinol Metab. 2010 12 (4): 352-8. 21-Meshkani R,Taghikhan M,Larijani B,Khatami S,Khoshbin E and Adeli KH.The relationship between homeostasis model assessment and cardiovascular risk factors in Iranian subjects with normal fasting glucose and normal glucose tolerance.Clinica Chimica Acta. 2006 371: 163-175. 22- Spencer CA, Hollowell JG, Kazarosyan M, Braverman LE. National health and nutrition examination survey III thyroid-stimulating hormone (TSH)-thyroperoxidase antibody relationships demonstrate that TSH upper reference limits may be skewed by occult thyroid dysfunction. J Clin Endocrinol Metab. 2007 92(11): 4236-40. 23- Surks MI, Goswami G, Daniels GH. The thyrotropin reference range should remain unchanged. J Clin Endocrinol Metab. 2005 90(9): 5489-96.