Excessive Thyroid Activity - Causes, Symptoms, and Treatment Methods

Hyperthyroidism, medically known as hyperthyreosis, is a condition where the thyroid gland produces too much T3 and T4 hormones. The thyroid gland is a small gland located at the lower end of the neck. The hormones it produces include thyroxine (T4), triiodothyronine (T3), and calcitonin. Calcitonin is responsible for maintaining the body's calcium levels. Hyperthyroidism can be caused by various factors such as Graves' disease, thyroiditis, thyroid nodules, or excessive iodine intake. Symptoms of hyperthyroidism can include excessive sweating, rapid heartbeat, tremors of the hands, weight loss, muscle weakness, sleep disturbances, decreased heat tolerance, and memory and concentration difficulties.

Thyroid hyperactivity may be caused by the following factors: Graves' disease, nodular autonomous hyperthyroidism (Plummer's disease - multiple autonomous adenomas, Goetsch's disease - single thyroid nodule, scattered microadenomas throughout the thyroid gland), iodine-Basedow syndrome, hypermetabolism due to excessive iodine load, hyperfunction associated with other thyroid disorders such as inflammations or tumors, excessive intake of iodine or thyroid hormones during treatment for hypothyroidism, transient hyperthyroidism in the course of thyroiditis, such as Hashimoto's thyroiditis, and secondary hyperthyroidism due to excessive TSH secretion from the pituitary gland. Graves' disease is the most common cause of thyroid hyperactivity and has an autoimmune origin. The body produces autoantibodies against the TSH receptor (TRAb), which stimulate the thyroid receptors to release increased amounts of the thyroid hormones T3 and T4. The exact cause of the disease is not known, but a combination of genetic and environmental factors is suspected. Nodular autonomous hyperthyroidism is another common cause of thyroid hyperactivity and develops due to increased growth of the thyroid epithelial tissue, which produces thyroid hormones independently of TSH.

The symptoms of hyperthyroidism are the result of an excessive release of thyroid hormones. The thyroid gland and its hormones control a number of metabolic processes, such as protein, fat, and carbohydrate metabolism, energy conversion and heat production, brain and peripheral nervous system function, and calcium-phosphate and water economy.

A thyroid crisis is a dangerous condition that can pose a threat to your health or even your life. Symptoms of a thyroid crisis resemble those of hyperactivity, but are more severe. It can occur in people with undiagnosed or improperly treated thyroid dysfunction. Causes of a crisis can include infection, serious illness, surgery, overexposure to thyroid hormones, severe stress, pregnancy. Symptoms of a thyroid crisis include: increased levels of thyroid hormones, high fever (up to 40°C), excessive sweating and dehydration, excessive excitation or the opposite leading to coma, symptoms of heart failure. In case of a thyroid crisis, the mortality rate is 30-50%, therefore a thyroid crisis requires immediate hospitalization.

Diagnosing excessive thyroid gland activity involves conducting laboratory tests to measure TSH levels, which is currently the most sensitive indicator of TSH and fT4 disorders. If TSH levels are found to be lower than the reference range, additional tests for fT3 and fT4 are recommended. However, it is important to note that a normal TSH level does not always indicate a normal thyroid function, as it can also be observed in cases of subclinical and secondary hyperthyroidism. Although TSH levels within the reference range typically indicate a normal thyroid function, it is important to note that the regulatory point for fT4, which regulates TSH secretion by the pituitary gland, can vary from person to person. Measuring fT3 levels is useful in predicting a relapse of Graves' disease or in cases of suspected amiodarone-induced hyperthyroidism. Depending on the type of hyperthyroidism, TSH levels may vary. In primary hyperthyroidism, TSH is decreased, while in secondary hyperthyroidism, it may be increased or normal. In the diagnosis of hyperthyroidism, immunological tests can also be helpful in determining the presence of TSH receptor antibodies (TRAb), which can be useful in identifying the cause of hyperthyroidism. Other supportive laboratory tests that can be helpful in diagnosing hyperthyroidism include a complete blood count (CBC), lipid profile (reduction in total cholesterol and LDL, slight increase in HDL and reduction in triglycerides), increase in alkaline phosphatase (ALP) activity, and increase in total calcium levels. If there is a suspicion of hyperthyroidism with a morphological cause, an ultrasound examination (USG) is performed. Hyperthyroidism should be distinguished from anxiety disorders and adrenal medullary tumors, as an excess of catecholamines can produce similar symptoms to an excess of thyroid hormones.

The treatment of chronic hyperthyroidism depends on the cause of the disease and other factors such as age, severity, and the presence of other diseases. Physicians select the treatment method individually, which may include: - Thyroid medications such as tiamazole and propylotiouracil, which reduce the production of thyroid hormones, - Beta-blockers as a supportive therapy, used in patients with cardiovascular diseases and tremors, - Radioactive iodine therapy, which is not recommended for pregnant and breastfeeding women, - Surgical removal of the thyroid gland, used in cases of suspected thyroid cancer. In addition to medication, diet also plays an important role in the treatment of chronic hyperthyroidism. The diet should be balanced and based on the principles of a healthy diet, as patients with hyperthyroidism often experience weight loss. The diet should include: - Foods with high energy and nutrient content such as dried fruits, seeds, nuts, avocado and vegetable oils, - Proteins from lean meats, fish, eggs, and raw legumes, - Fats mainly of plant origin, rich in omega-3 fatty acids, such as olive oil, flaxseed oil, rapeseed oil, flaxseed, pumpkin seeds, sunflower seeds, avocado, - Carbohydrates mainly from whole grain products, vegetables and fruits, - Calcium and vitamin D, which are important for bone homeostasis, - Iodine, which plays an important role in thyroid function but in excess can lead to hyperthyroidism, - Omega-3 fatty acids, which have immunostimulatory and anti-inflammatory effects.