Function of the Thyroid Gland and Prevalence of Thyroid DiseaseThe thyroid gland, known as the “engine” of the human body, is a small, butterfly-shaped organ located in front of the windpipe that plays a key role in regulating many of our body’s functions, including those related to reproduction. The thyroid gland makes, stores and releases thyroid hormones into the bloodstream to regulate the body’s metabolism. These hormones are important for keeping the body’s tissues and organs functioning properly. They enable the body to use stored energy more efficiently, maintain body temperature, and keep muscles working properly. When the thyroid gland is diseased, it is difficult to fulfill these roles. Thyroid disease is the second most common endocrine system disorder after diabetes. More than 300 million people worldwide suffer from thyroid disease, but many of them are unaware of it. The most common thyroid disorders are abnormalities of thyroid function and diseases of the thyroid gland itself. The main diseases are: (1) hyperthyroidism; (2) hypothyroidism; (3) simple goiter; (4) thyroid nodules: adenomas, cysts, thyroid cancer, etc.; and (5) thyroiditis: suppurative, subacute, and chronic lymphocytic thyroiditis (Hashimoto’s thyroiditis), postpartum thyroiditis, and painless thyroiditis. The thyroid gland and other human systems (such as the respiratory system, etc.) have obvious differences, but and the nervous system are closely linked, interacting with each other and cooperating with each other, known as the two major biological information systems, without their close cooperation, the body’s internal environment can not maintain relative stability. So what are the physiological functions of thyroid hormone secreted by the thyroid gland? ① Promote metabolism, so that the vast majority of tissues to increase oxygen consumption, and increase heat production; ②, to promote growth and development, the development of bones, brain and reproductive organs is essential; ③ increase the excitability of the central nervous system. In addition, it also enhances and regulates the effects of other hormones and accelerates the heart rate, strengthens myocardial contractility and increases cardiac output. Recent studies have shown that the incidence of thyroid diseases is very high and even affects people’s physical and mental health. One of the most common thyroid nodules, the incidence of the general population of 4% to 7%, but recently the hospital health checkups found that the incidence of its incidence has increased to 30% to 69%, the United States each year there are about 250,000 new patients, and 5% for malignant nodules. The term “thyroid nodule” here is a morphological description, which includes tumors, cysts, masses of normal tissue, and thyroid masses caused by other diseases. Thyroid tumor is a common disease, and its incidence rate varies greatly in different regions. Generally, the incidence rate of thyroid tumor is higher in areas where goiter is endemic than in non-endemic areas. The incidence of thyroid tumors is generally higher in goiter-endemic areas than in non-endemic areas. Thyroid cancer has a tendency to increase gradually in recent years, with 80% of single nodules proved to be benign by surgery, 20% malignant, and about 10% malignant in multiple nodules. In terms of gender, thyroid diseases are more common in females, and its incidence rate is four times higher in females than in males, but in terms of the proportion of thyroid cancer, males are higher than females; the incidence rate of benign and malignant thyroid nodules is similar in each age group, but the incidence rate of thyroid cancer is high in children’s thyroid nodules, so special attention should be given to the possibility of carcinoma in children’s thyroid nodules. What can cause thyroid disease What causes thyroid disease? Many causes can lead to thyroid disease. Endemic goiter is mainly caused by lack of iodine in the environment, resulting in insufficient iodine intake; sporadic goiter is mainly caused by congenital thyroid hormone synthesis disorders or goiter-causing substances, etc. A lot of thyroid disorders, such as hyperthyroidism and Hashimoto’s thyroiditis, are related to the patient’s individual immune dysfunction and genetic factors. However, with the improvement of living standard and the popularization of iodized salt, the occurrence of high canonical thyroid disease should not be ignored. Other physiologic changes, such as psychiatric elements and women’s pregnancy, have an important influence on the development of thyroid diseases. The causes of a few thyroid disorders are not well understood. How to tell if you have thyroid disease Most people with thyroid disease can have no symptoms. You should think about the possibility of hyperthyroidism when you experience symptoms such as fear of heat, excessive sweating, panic, fatigue, changes in appetite, diarrhea, and weight loss. When you notice symptoms such as chills, swelling, weight gain, dry skin, and loss of appetite, you should be aware of the possibility of hypothyroidism. When you feel pain and fever in the neck, especially when you can feel a lump in the thyroid gland and have pressure pain, you should think of the possibility of subacute thyroiditis. When you find thickening or lumps in the neck, even if there is no discomfort, you should think about whether you have thyroid disease. When you encounter the above situations, you should consult the endocrinology department of the hospital in time so as to get timely diagnosis and reasonable treatment. Doctors diagnosing thyroid disease will generally understand the patient’s development, nutrition, height, weight, expression, posture, skin, hair, eyes, blood pressure, heart, muscles, limbs and other aspects of life and living and eating habits, which are important references for the correct diagnosis. For the examination of the thyroid gland itself, the doctor will note whether the thyroid gland is enlarged, whether there are nodules on the thyroid gland, and what the nature of the nodules is. However, it is important to note that there are a number of patients with thyroid disease who do not have an enlarged thyroid gland. What are the treatments for thyroid disorders Similar to other endocrine disorders, thyroid disorders are generally treated with functional and etiologic treatments. For over-functioning thyroid disease, there are three commonly used methods: anti-thyroid medication, radioactive iodine (131I) therapy and subtotal thyroidectomy surgery. For the selection of each method, the choice should be based on a comprehensive judgment of the condition, environment and other conditions. Antithyroid medication: The representative medications are methimazole and propylthiouracil; foreign studies have shown that propylthiouracil can lead to serious liver side effects, and both recommend methimazole as the preferred medication. The advantage is that it can retain the function of the thyroid gland to produce thyroid hormones, the disadvantage is that the treatment course is long, the cure rate is low, and the recurrence rate is high, which is suitable for patients with mild condition and mildly enlarged thyroid gland. The age of 20 years old, pregnancy hyperthyroidism, old and frail people and those who are not adapted to 131I and surgical treatment are suitable for drug treatment. 131I treatment: 131I treatment of hyperthyroidism has the advantages of simplicity, short course of treatment, low recurrence rate, and the cure of one dose of medicine reaches about 80%. A large number of studies have shown that the method is safe and has no adverse effect on fertility and offspring development, and there is no risk of cancer or leukemia. Iodine deficiency is a high incidence of post-treatment hypothyroidism, but good efficacy can be obtained through thyroxine supplementation in all cases, and normal pregnancy or breastfeeding can be achieved during the replacement process. Adults with more than moderate hyperthyroidism and moderately enlarged thyroid glands should be primarily selected. Postoperative recurrence of hyperthyroidism, hyperthyroidism heart disease, hyperthyroidism in the elderly, hyperthyroidism combined with other medical diseases are preferred to 131I treatment. The use of radioactive iodine treatment is contraindicated in pregnant and lactating women, and 131I treatment is preferred in adolescents and in those with high concentrations of thyroid peroxidase antibodies, because 131I treatment can easily lead to permanent hypothyroidism. Surgery: Since 131I treatment of hyperthyroidism can achieve the same effect as sub-total thyroidectomy, surgery for hyperthyroidism is used both at home and abroad as a supplement to antithyroid medication and 131I, and is no longer used as the main treatment method. It is mainly applied to middle and severe hyperthyroidism with obvious enlargement of thyroid gland, especially nodular goiter with hyperthyroidism, with the advantages of short course of treatment and low recurrence rate, and the disadvantages of trauma, affecting the appearance, and certain surgical complications, such as injury to parathyroid glands, laryngeal reentry nerve injury, hypothyroidism and so on. For hypothyroidism, thyroxine replacement therapy is mainly given, and the commonly used drugs are levothyroxine (Euthyrox, Rettis, GHB), and thyroid tablets have tended to be phased out due to their unstable performance and high side effects. Regarding the heredity of thyroid diseases, it is not possible to generalize, except to say that some thyroid diseases such as hyperthyroidism, hypothyroidism, Hashimoto’s thyroiditis and some thyroid cancers are hereditary, and a person with a family history of related thyroid diseases may be more susceptible to such diseases under the influence of environmental factors. What to Expect When Pregnant and Breastfeeding with Thyroid Disease Ensuring adequate iodine nutrition and thyroid function in pregnant and breastfeeding women is critical for the maturation of brain development in the fetus and early postnatal period. Women with thyroid disorders should consult an endocrinologist for advice on the appropriate timing of pregnancy before becoming pregnant, and then visit an endocrinologist promptly after pregnancy for laboratory tests to check the state of thyroid function and urinary iodine, in order to determine the need for medication or to adjust the dose of medication. If hypothyroidism is detected before and during pregnancy, levothyroxine should be given promptly to achieve TSH <2.5 before pregnancy and ft4 at the upper limit of the reference range during pregnancy, in order to avoid the possible adverse effects of hypothyroidism on the intellectual development of the fetus. If hyperthyroidism is detected before pregnancy, anti-thyroid medication should be used to control hyperthyroidism, i.e., thyroid function indexes are normal or close to normal, and pregnancy can be carried out by using the smallest amount of anti-thyroid medication - propylthiouracil (50mg per day), or by discontinuing the use of anti-thyroid medication for pregnancy and then rechecking the thyroid function after pregnancy, and thyroid function is maintained as normal, and continued observation is sufficient. The same principle applies to the management of hypothyroidism and hyperthyroidism during lactation.