What is Hyperthyroidism?
Hyperthyroidism refers to any one of a number of disorders where there is an excess of thyroid hormones. It is mostly caused by an over functioning of the thyroid gland but is sometimes caused instead by a pituitary tumor or inflammation of the thyroid and it results in a hypermetabolic state which causes symptoms like weight loss, heat intolerance, rapid heart rate, and hyperactivity. It is sometimes referred to as thyrotoxicosis, is a condition that is caused by having excess thyroid hormones. Thyroid hormone production is under the control of the hypothalamus and the pituitary. The condition is also called thyrotoxicosis and is generally due to overproduction from the thyroid gland. Normally, the hypothalamus which is located at the base of the brain detects low blood levels of thyroid hormones and releases thyrotropin releasing hormone into the hypophyseal portal system which is a network of capillaries linking the hypothalamus to the anterior pituitary. The anterior pituitary then releases the thyroid-stimulating hormone also called thyrotropin or simply TSH. TSH stimulates the thyroid gland which is a gland located in the neck that looks like two thumbs hooked together in the shape of a V. The thyroid gland is made up of thousands of follicles which are small spheres lined with follicular cells. These cells convert thyroglobulin a protein found in follicles into 2 iodine-containing hormones namely triiodothyronine or t3 and thyroxine or t4. Once released from the thyroid gland these hormones enter the blood and bind the circulating plasma proteins only a small amount of t3 and t4 will travel unbound in the blood and these two hormones get picked up by nearly every cell in the body. Once it is inside the cell t4 is mostly converted to t3 or it can exert its effect. T3 speeds up the cells basal metabolic rate so as an example the cell might produce more proteins and burn up more energy in the form of sugars and fats. If the cells are in a bit of a frenzy t3 increases cardiac output stimulates bone reabsorption thinning out the bones and then activates the sympathetic nervous system the part of the nervous system responsible for our fight-or-flight response.
Thyroid hormone is important and the occasional increase can be really useful when you need a boost to get through the final rounds of sporting competition or when you are trying to stay warm during a snowstorm. Hyperthyroidism can happen a few different ways all of them result in too much thyroid hormone in a hypermetabolic state where cellular reactions are happening faster than normal. The most primary cause is Graves disease an autoimmune disorder where B cells produce antibodies against several thyroid proteins and these autoantibodies include thyroid-stimulating immunoglobulins which bind to the TSH receptor on the follicular cells and imitate TSH. This results in the growth of the thyroid glands and stimulates the Pelicula cells to produce excess thyroid hormone. Another primary cause is toxic nodular goiter where one or more follicles start generating lots of thyroid hormone. In some cases, it’s because of a mutated TSH receptor that inappropriately keeps these follicular cells active. A different cause is a hyperfunctioning thyroid adenoma where the follicular cells start growing uncontrollably forming a benign tumor that makes excess thyroid hormones. Also, anytime the thyroid gets inflamed or damaged there can be a large release of preformed thyroid hormones. There is also JOD-BASEDOW SYNDROME or iodine-induced thyrotoxicosis which can develop soon after an iodine-deficient person gets a hefty dose of iodine and finally neonatal hyperthyroidism which is when newborns who have mothers with Graves disease start generating too much thyroid hormone in response to thyroid-stimulating immunoglobulin that crosses the placental barrier and enters the baby. A secondary cause of hyperthyroidism is when there is a healthy thyroid that generates a lot of thyroid hormone in response to a TCH secreting tumor in the anterior pituitary. The symptoms of hyperthyroidism include weight loss despite an increase in appetite because of the higher basal metabolic rate, heat intolerance because the body is producing more heat and rapid heart rate, sweating, hyperactivity, anxiety, and insomnia because of the effects of the thyroid hormones on the sympathetic nervous system. Sympathetic overstimulation of muscles that control eye movements also makes the eyes appear more open than normal so you see more of the whites of the eyes.
If the hyperthyroidism has been ongoing for a long time there is a risk of developing congestive heart failure and osteoporosis. A thyroid storm is a life-threatening complication of hyperthyroidism where the body goes into a state of severe hypermetabolism it can develop when someone with hyperthyroidism stops their treatment develops an infection or has surgery. All the normal symptoms of hyperthyroidism become exaggerated for example heat intolerance turns into a high fever and rapid heart rate turns into cardiac arrhythmia. Treatment varies based on the exact cause of hyperthyroidism but generally involves drugs like Beta-Blockers to treat the immediate symptoms and anti-thyroid drugs to block thyroid hormone production and release. Radioiodine therapy can be used to partially or completely destroy thyroid function followed by a replacement hormone therapy. In a few cases, the thyroid is removed with surgery.
What are the causes of hyperthyroidism?
The most common causes of hyperthyroid conditions.
- Lifestyle Factors: Lifestyle factors are perhaps the biggest factor which leads to a hyperthyroid condition. Through the biggest lifestyle factors which can lead to hyperthyroidism are stress and poor eating habits with regards to stress while there is nothing we can do to eliminate the stress in our lives most people can do a much better job of handling stress too much stress can create problems with the adrenal glands as well they are designed to handle acute stress conditions they cannot adequately handle chronic stress. Problems with adrenal glands will eventually affect other areas of the body including the thyroid gland. Poor eating habits can also stress out the adrenal as when we eat too many refined foods and sugars this causes problems with the blood sugar levels which once again over time will affect the adrenal glands and can also cause malfunctioning of the thyroid gland. If the adrenal glands are not addressed not only will the thyroid gland continue to malfunction but very well can lead other problems such as insulin resistance and eventually type-2 diabetes. In addition, many people with hyperthyroidism will develop the autoimmune thyroid condition Graves disease which can be even more challenging to manage while most endocrinologist will recommend either anti-thyroid drugs or radioactive iodine as a treatment method for Graves disease not addressing the actual cause of this disorder can lead to other autoimmune conditions in the future.
- Environmental Toxins: It is no coincidence that over the last half-century we have had a dramatic increase in a number of thyroid conditions and at the same time have had a huge increase in the number of toxins we are exposed to. Although we can’t eliminate all the toxins we are exposed to we can do some things to reduce our exposure to them. one of the things we can do is to reduce the number of toxins used in a home and the other thing you can do to reduce toxins is to purchase natural household products.
- Genetics: Genetics can lead to the hyperthyroid condition it doesn’t play as big of a role in the development of such conditions as many people think. But what some researchers are finding is that some people have genetic tendencies for a thyroid condition but despite this other factors will determine whether or not they will develop the condition.
What are the symptoms of Hyperthyroidism?
People with mild disease usually experience no symptoms but the symptoms become more obvious as the degree of hyperthyroidism increases. The symptoms usually are related to an increase in the metabolic rate of the body.
Common symptoms include:
- Excessive sweating
- Heat intolerance
- Increased bowel movements
- Nervousness, agitation, anxiety
- Rapid heart rate, palpitations, irregular heart rate
- Weight loss
- Fatigue, Weakness
- Decreased Concentration
- Fine or brittle hair
- Sleep disturbances
How to diagnose Hyperthyroidism?
Diagnosing hyperthyroidism is done by measuring blood levels of TSH t3 and t4. If it is due to a primary cause, TSH will be low and unbound thyroid hormones will be high. Once hyperthyroidism is confirmed, a radioactive iodine uptake test and a thyroid scan help determine the specific cause of the disorder. Tests for hyperthyroidism are based on an individual basis.
What are the treatment options for Hyperthyroidism?
A doctor determines which patients to treat based on a number of variables including the underlying cause of hyperthyroidism, the age of the patient, the size of the thyroid gland, and the presence of the co-existing medical illnesses. The options for treating hyperthyroidism include treating the symptoms of the condition with medications, antithyroid drugs, radioactive iodine, and surgery.
- Medications: Following are the medications that treat hyperthyroidism symptoms caused by excessive thyroid hormones, such as a rapid heart rate are Beta-Blockers, propranolol (Inderal), atenolol (Tenormin), and Metoprolol (Lopressor). These medications counteract the effect of thyroid hormone to increase metabolism, but they do not alter the levels of thyroid hormones in the blood. Beta-blockers can relieve symptoms like rapid heart rate and reduce hand tremors until other treatments start to work.
- Antithyroid drugs: These drugs stop the thyroid gland from producing too much thyroxine or triiodothyronine. Methimazole or propylthiouracil (PTU) may be used. After starting a treatment, it may take several weeks or months for hormone levels to adjust to the normal range. On average, total treatment time is between 1 and 2 years, but it can take longer. Adverse effects of medications include allergic reactions, reduction in white blood cells, increasing the chance of infections and liver failure (occurs rarely).
- Radioactive Iodine: Radioactive Iodine is given orally (either by pill or liquid) on a one-time basis to gradually remove the hyperactive gland. The iodine is given for ablative treatment is different from the iodine used in a scan. Radioactive iodine is given after a routine iodine scan, and uptake of the iodine is determined to confirm hyperthyroidism. There are no widespread side effects with this therapy. Usually, more than 80% of patients are cured with a single dose of radioactive iodine. It takes between 8 to 12 weeks for the thyroid to become normal after therapy. Permanent hypothyroidism is the major complication of this form of treatment. While a temporary hypothyroid state may be seen up to 6 months after treatment with radioactive iodine, if it persists longer than 6 months, thyroid replacement therapy usually is begun.
- Surgery: A section or all of your thyroid gland may be surgically removed. You will then have to take thyroid hormone supplements to prevent hypothyroidism, which occurs when you have an underactive thyroid that secretes too little hormone. Also, beta-blockers such as propranolol can help control your rapid pulse, sweating, anxiety, and high blood pressure or hypertension. Most people respond well to this treatment.
What is the difference between hyperthyroidism and hypothyroidism?
Hyperthyroidism refers to an increased production of the thyroid hormone by the thyroid gland, while hypothyroidism refers to a condition in which a person has too little thyroid hormone or underproduction of thyroid hormones.
Which types of doctors treat hyperthyroidism?
Endocrinologists are specialists in diagnosing and treating hormonal disorders such as hyperthyroidism. Primary care physicians, including family practitioners and internists, may also be involved in treating patients with hyperthyroidism. Ophthalmologists and ophthalmic surgeons may be involved in the care of patients with Grave’s disease.
Conclusion: Hyperthyroidism is the commonest endocrine disorder. The disease causes increased metabolism and patients lose weight despite huge appetites and they may become restless and irritable. However, effective treatment options are available. A treatment option should be selected based on the assessment of the patient’s situation as well as their personal values and preferences.