Why Regular Check-Ups are Important for Women with Type 1 Diabetes and Hypothyroidism

Many people with type 1 diabetes (T1D) have hypothyroidism.(1) Additionally, females are more likely to have hypothyroidism than males due to many possible factors, such as hormones, that are not well-understood.(1–4) Diabetes and hypothyroidism are both hormone disorders.(5,6) Hormones are chemical messengers that flow through your bloodstream to tissues or organs and have many different slow-acting effects on the body.(7) Insulin hormone (related to diabetes), thyroid hormones (related to hypothyroidism), and estrogen hormone (related to females) all affect each other.(8–14) Therefore, it is important for females with T1D and hypothyroidism to see their physicians regularly to monitor hormones that are known to be sensitive to each other.(15)

Information About Type 1 Diabetes:

·   Definition: Type 1 diabetes (T1D) is an autoimmune disease, which results in the loss of beta cells that produce insulin.(5) Eventually, this leads to a complete absence of insulin and high amounts of sugar in the blood.(5) Autoimmune diseases are when the person’s immune cells attack their healthy cells.(16)

·  Cause: T1D results from a combination of inheriting certain genes from the person’s parents as well as environmental factors that are not well-understood.(5)

·  Signs/Symptoms: These include an increased and frequent need to urinate and drink fluids; weight loss; increased and excessive hunger; blurred vision; and slowed growth.(5) Additionally, the affected person may have increased infections. If it is left untreated, the person can die from uncontrolled high blood glucose.

·  Treatments: The treatment for people with T1D is insulin.(5)

Information About Hypothyroidism:

·  Definition: Hypothyroidism is when the thyroid gland does not work properly and does not make enough thyroid hormones necessary for many body functions.(6)

·  Cause: There are several causes of hypothyroidism, but Hashimoto’s disease, an autoimmune disorder, is the most common cause. Females are more likely to have autoimmune conditions such as Hashimoto’s.(17-19) Additionally, when a person has one autoimmune disease such as diabetes(5), they are more likely to have other additional autoimmune diseases.(1,19)  

·  Sign/Symptoms: Signs and symptoms include tiredness; weight gain; a puffy face; feeling abnormally cold; pain in the joints and muscles; constipation; dry skin and hair; thinning hair; decreased sweating; abnormal menstrual periods; decreased fertility; depression; slow heart rate; and a swollen thyroid in the neck (goiter).(6)

·  Treatments: The treatment is to take medication that contains thyroid hormones.(6)

What is Insulin?

Insulin is a hormone produced by the pancreas.(8) Cells need energy from glucose, a type of sugar, and insulin allows the glucose to enter the cells. Insulin helps to decrease blood glucose when the glucose moves from the blood into the cells. This is important when blood glucose increases after eating or when the liver releases glucose into the blood, especially during fasting.

What are Thyroid Hormones?

Some important thyroid hormones include T3 and T4.(20) They control metabolism, growth, and various other functions of the body. Thyroid hormones can increase metabolism, meaning that proteins such as the insulin hormone get broken down faster.(21) When insulin is broken down faster in the body, it cannot work as well to bring down blood glucose levels. Conversely, if thyroid hormones are low such as with hypothyroidism, metabolism slows down, and insulin is not broken down as fast. That means that the insulin works in your body longer and can cause low blood glucose.

What is Estrogen?

Estrogen is a hormone that gives females their sex characteristics and helps with other body functions such as growth of long bones.(22) The levels of estrogen change throughout the natural life stages of women, such as during puberty, pregnancy, and menopause.(15) The levels of estrogen also impact the levels of thyroid hormones and their functions.(11-13)

Conclusion:

When estrogen interacts with disease processes, it can affect overall health.(8–14) If you are a female with both T1D and hypothyroidism, you may need to have your physician adjust your thyroid medication dosages throughout the different life stages as estrogen levels change.(11,23–26) It is important for females with T1D to have their thyroid hormone levels in the healthy range because thyroid hormones also affect blood glucose levels.(14)

It is my hope that the lessons learned here will help shift the way female bodies are viewed and treated in the medical field and beyond. As various chronic illnesses are impacted by the menstrual cycle and ovarian hormones, “women are not small men,” (coined by Dr. Staci Sims, PhD), and we must Heed Her Health.

References

1.    Bao YK, Weide LG, Ganesan VC, et al. High prevalence of comorbid autoimmune diseases in adults with type 1 diabetes from the HealthFacts database. Journal of Diabetes. 2019;11(4). doi:10.1111/1753-0407.12856

2.    Virta LJ, Eskelinen SI. Prevalence of hypothyroidism in Finland—a nationwide prescription study. European Journal of Clinical Pharmacology. 2011;67(1). doi:10.1007/s00228-010-0884-4

3.    Kronzer VL, Bridges SL, Davis JM. Why women have more autoimmune diseases than men: An evolutionary perspective. Evolutionary Applications. 2021;14(3):629-633. doi:10.1111/eva.13167

4.    Rider V, Foster RT, Evans M, Suenaga R, Abdou NI. Gender Differences in Autoimmune Diseases: Estrogen Increases Calcineurin Expression in Systemic Lupus Erythematosus. Clinical Immunology and Immunopathology. 1998;89(2):171-180. doi:10.1006/clin.1998.4604

5.    American Diabetes Association. Diagnosis and Classification of Diabetes Mellitus. Diabetes Care. 2010;33(1).

6.    MedlinePlus. Hypothyroidism. National Institutes of Health.

7.    MedlinePlus. Hormones. National Institutes of Health.

8.    National Institute of Diabetes and Digestive and Kidney Disease. Insulin Resistance & Prediabetes. National Institutes of Health.

9.    Gupte AA, Pownall HJ, Hamilton DJ. Estrogen: An Emerging Regulator of Insulin Action and Mitochondrial Function. Journal of Diabetes Research. 2015;2015. doi:10.1155/2015/916585

10.  Kanaya AM, Herrington D, Vittinghoff E, et al. Glycemic Effects of Postmenopausal Hormone Therapy: The Heart and Estrogen/progestin Replacement Study: A Randomized, Double-Blind, Placebo-Controlled Trial. Annals of Internal Medicine. 2003;138(1). doi:10.7326/0003-4819-138-1-200301070-00005

11.  Tahboub R, Arafah BM. Sex steroids and the thyroid. Best Practice & Research Clinical Endocrinology & Metabolism. 2009;23(6). doi:10.1016/j.beem.2009.06.005

12.  Arafah BM. Increased Need for Thyroxine in Women with Hypothyroidism during Estrogen Therapy. New England Journal of Medicine. 2001;344(23). doi:10.1056/NEJM200106073442302

13.  AIN KB, MORI Y, REFETOFF S. Reduced Clearance Rate of Thyroxine-Binding Globulin (TBG) with Increased Sialylation: A Mechanism for Estrogen-Induced Elevation of Serum TBG Concentration*. The Journal of Clinical Endocrinology & Metabolism. 1987;65(4). doi:10.1210/jcem-65-4-689

14.  Pandolfi C, Pellegrini L, Dedè A. [Blood glucose and insulin responses to oral glucose in hyperthyroidism]. Minerva endocrinologica. 1996;21(2).

15.  Braude P, Hamilton-Fairley D. Hormonal Changes during Puberty, Pregnancy, and the Menopause. In: Black M, Ambros-Rudolph CM, Edwards L, Lynch PJ, eds. Obstetric and Gynecologic Dermatology. 3rd ed. Elsevier; 2008. doi:10.1016/B978-0-7234-3445-0.10001-3

16.  National Cancer Institute. NCI Dictionaries . National Institutes of Health. Accessed November 6, 2021. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/autoimmune-disease

17.  Ngo ST, Steyn FJ, McCombe PA. Gender differences in autoimmune disease. Frontiers in Neuroendocrinology. 2014;35(3). doi:10.1016/j.yfrne.2014.04.004

18.  Brix TH, Knudsen GPS, Kristiansen M, Kyvik KO, Ørstavik KH, Hegedüs L. High Frequency of Skewed X-Chromosome Inactivation in Females with Autoimmune Thyroid Disease: A Possible Explanation for the Female Predisposition to Thyroid Autoimmunity. The Journal of Clinical Endocrinology & Metabolism. 2005;90(11). doi:10.1210/jc.2005-1366

19.  Ruggeri R, Trimarchi F, Giuffrida G, et al. Autoimmune comorbidities in Hashimoto’s thyroiditis: different patterns of association in adulthood and childhood/adolescence. European Journal of Endocrinology. 2017;176:133-141.

20.  Shahid M, Ashraf M, Sharma S. Physiology, Thyroid Hormone. StatPearls; 2021. Accessed November 6, 2021. https://www.ncbi.nlm.nih.gov/books/NBK500006/

21.  Joslin Diabetes. Diabetes and Thyroid Disease. Joslin Diabetes. Published 2021. Accessed November 6, 2021. https://www.joslin.org/patient-care/diabetes-education/diabetes-learning-center/diabetes-and-thyroid-disease

22.  National Cancer Institute. NCI Dictionaries. National Institutes of Health. Accessed November 6, 2021. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/estrogen

23.  Mazer NA. Interaction of Estrogen Therapy and Thyroid Hormone Replacement in Postmenopausal Women. Thyroid. 2004;14(supplement 1). doi:10.1089/105072504323024561

24.  Velia IP PCBSKC. Pediatric and Adolescent Chronic Thyroid Autoimmune Disease. In: Velia I, Paul C, Brink S, Krzisnik C, eds. Pediatric Endocrinology and Diabetes. Mirton; 2017:21-21.

25.  Alexander EK, Marqusee E, Lawrence J, Jarolim P, Fischer GA, Larsen PR. Timing and Magnitude of Increases in Levothyroxine Requirements during Pregnancy in Women with Hypothyroidism. New England Journal of Medicine. 2004;351(3). doi:10.1056/NEJMoa040079

26.  Baehr KM, Lyden E, Treude K, Erickson J, Goldner W. Levothyroxine dose following thyroidectomy is affected by more than just body weight. The Laryngoscope. 2012;122(4). doi:10.1002/lary.23186