MANILA, Philippines - A slowing down of the physical or mental functions is usually accepted as the normal course of old age, rather than being diagnosed as an illness or condition that may be treated with proper nutrition, hormones, exercise, or a change of lifestyle. Perhaps one of the under-diagnosed health problems in old age is hypothyroidism, an insufficient production or absorption of the thyroid hormone that won't allow our metabolism to function at its peak efficiency.
What is the thyroid?
The thyroid is a small, butterfly-shaped gland located in the neck, over the trachea, or windpipe, just below the larynx. The thyroid has tremendous responsibilities, as it is the gland that affects virtually all metabolic processes and is vital for the normal function of every cell in the body. It does this by releasing certain hormones known as thyroxine (T4) and triiodothyronine (T3), which in turn regulate the body's metabolism, temperature, and heart rate. Should it produce too little or too much, all kinds of bad things begin to happen.
How do you make thyroid hormone?
In order to be sure you're getting all the thyroid hormone your body needs, it's helpful to understand how your body makes it. The whole process begins with the hypothalamus, the body's "thermostat," which regulates many hormonal activities. When the hypothalamus determines that the blood levels of thyroid hormone (TH) have fallen too low, it sets a chain of activity in motion by discharging thyroid releasing hormone (TRH). TRH signals the pituitary to release a second hormone, thyroid stimulating hormone (TSH). Finally, TSH tells the thyroid gland to get to work, and the thyroid gland produces thyroid hormone. When the thyroid hormone have risen high enough for the body to function properly, the pituitary responds by ceasing to release TSH and the process stops, until the hypothalamus determines that it's time to start again.
Hypothyroidism
Hypothyroidism is not diagnosed often enough. There are many people who are tired, restless, chronically constipated, overweight, and with falling hair, women whose menstrual flow is too heavy, with dry skin. Identifying hypothyroidism requires a high index of suspicion by you and your physician, followed by blood tests that measure how much thyroid stimulating hormone (TSH) is being produced by the brain and how much thyroid hormone is actually circulating in your body.
There are two ways that the body can come to suffer from insufficient thyroid hormone. One is the thyroid itself has difficulty producing it. Lack of iodine, a tumor, or some other thyroid problem may result in a gland that doesn't properly carry out the orders given by the hypothalamus and the pituitary gland. This is known as primary hypothyroidism. The other way that the thyroid hormone levels can fall is when the hypothalamus and/or the pituitary aren't functioning properly. This is known as secondary hypothyroidism.
The thyroid itself needs iodine to function. Lack of iodine will cause the thyroid to swell, a condition known as goiter, a visibly enlarged thyroid gland on the front and side of the neck. You need a very tiny amount of iodine, however - a daily dose of 100 micrograms (mcgs) for women and 120 mcgs for men. Most people get that in iodized salt or seafoods.
Hypothyroidism, sometimes called myxedema, is caused by underactivity of the thyroid gland. It can be due to one of several causes, or it can occur for no apparent reason. One occasional cause is treatment for hyperthyroidism, which carries a significant risk that the overactive gland may later become underactive.
Less often is a condition called "Hashimoto-thyroiditis" - a defect in the immune system that leads not only to hypothyroidism but also to enlargement of the thyroid and the formation of goiter. The other reason people develop hypothyroidism is as a result of surgery with radioactive iodine for the treatment of Graves disease, which is also an autoimmune disorder.
What are the symptoms?
The symptoms of hypothyroidism develop slowly, taking months or even years. Underactivity of the thyroid gland slows down the chemical reactions in the body, causing the following:
* Weight gain - most patient gain from five to ten kilograms, although your appetite is normal or less than normal.
* Sensitivity to cold - you'll feel the cold very badly. You may suffer from muscle stiffness and spasm.
* Mental problems - feel tired or sleepy, and slow down intellectually. Your reactions get slower. Some older people experience depression and paranoia.
* Slurred speech - voice becomes slow and husky.
* Heart problems - pulse rate is slow, some people develop high blood pressure, and chest pain could be the first symptom of hypothyroidism.
* Constipation - as a result of the general slowing down of the body's processes.
* Heavy periods - menstrual periods become heavier (hemorrhagic).
* Skin and hair problems - skin is likely to be rough and dry and to flake readily. It tends to be pale and your eyelids, hands and feet swell. Hair becomes dry and brittle and the outer part of the eyebrows may be missing.
* Loses of interest in sex.
* Nervous system disorders - you may become a little deaf and have trouble with your balance.
* Emotional instability - mood swings, easily upset, irritable, easily angered, nervous and anxious.
What should be done?
Many people feel tired and generally down at some time or other. However, most of them do not have hypothyroidism.
Depression mimics many of the symptoms of hypothyroidism. Your physician will probably ask for some blood analysis to determine the level of thyroid stimulating hormone (TSH), T3 and T4. If your physician suspects that you have an underactive thyroid gland, tests reveal low levels of the hormone T3 and T4 and high levels of TSH in your blood.
What is the treatment?
Whatever the cause, the treatment of hypothyroidism is straightforward. You will take medication containing artificially made thyroid hormones every day for the rest of your life. After a few days of treatment, you will feel much better, and after a few months you should return to normal health. Treatment is with thyroxine, which is available as 50 and 100 microgram tablets. Normally, thyroxine treatment begins slowly and you'll be prescribed a daily dose of 50 micrograms for three to four weeks, increasing to 100 micrograms daily. You'll then have another blood test some three months after starting treatment to assess whether any further minor adjustment of dose is necessary.
Hyperthyroidism
An overactive thyroid, hyperthyroidism or thyrotoxicosis, results from the overproduction of the thyroid hormones, T4 and T3, by the thyroid gland. In 75% of patients, this is the result of the presence of an antibody in the blood that stimulates the thyroid not only to secrete excessive amounts of thyroid hormones, but also to increase the size of the thyroid gland. This type of hyperthyroidism is called Graves disease. The cause of the antibody production is not known but it runs in the families; hence genes must play a role. There are some environmental factors that trigger the start of the disease in genetically susceptible individuals.
What are the symptoms?
An overactive thyroid gland causes the chemical reactions in the body to speed up, producing mental as well as physical symptoms.
* Weight loss - result because of the "burning off" of calories caused by the high levels of thyroid hormones in the blood.
* Heat intolerance and sweating - as the metabolism increases the body produces excessive heat, which it then gets rid of by sweating.
* Palpitations - aware of your heart beating faster than normal. In severe cases, particularly in more elderly people, there may be an irregular heartbeat, known as atrial fibrillation, and even heart failure.
* Irritability - you may find yourself increasingly unable to cope with stresses, sometimes bursting into tears with no apparent reason at all.
* Breathlessness - you get easily exhausted after climbing two or three flights of stairs.
* Tremors - handwriting may deteriorate, difficulty inserting a key into the lock.
* Changes in bowel movement - increase in frequency, softer than normal stool two to three times daily. Diarrhea can occasionally be a problem.
* Muscle weakness - thigh muscle becomes weak.
* Irregular periods - menstrual period becomes irregular, light or even absent. Women may find it difficult to conceive until the hyperthyroidism has been properly and adequately treated.
* Eye problems - excessive watering made worse by wind and bright light, pain and grittiness as if there is sand in the eyes, double vision and blurring of vision. Many sufferers develop exophthalmos (protruding eyes).
* Skin, hair, and nail problems - itchiness of the whole body, hair will probably become thinner and finer, nails will be brittle and become unsightly.
What should be done?
Similarly to the diagnosis of hypothyroidism, blood test is done and high levels of T3 and T4 and low levels of TSH can confirm overactive thyroid gland. Your physician may also request for thyroid scan to determine and obtain more information about the cause of the hyperthyroidism as this may affect the type of treatment that you will need.
What is the treatment?
Hyperthyroidism can be treated in one of three ways. The first possible treatment is to prescribe medication that contains antithyroid drugs. In most people the disorder is brought under control in about 8 weeks by this method, although you will have to continue to take medication for a prolonged period, sometimes for at least a year.
The second treatment is surgery. Surgery cures the disorder in about 90% of these cases. In a few cases, however, either the disease recurs or the thyroid becomes underactive as a result of surgery leading to hypothyroidism.
The third form of treatment consists of taking a dose of radioactive iodine in a form of a clear, slightly salty drink. Iodine is essential component of the thyroid hormone. There it acts on the glandular tissue to control the cellular overactivity slowly without exposing the rest of the body. If too much radiation is administered, the thyroid gland may become underactive, and you may have to take medication to compensate.
Each form of treatment has its advantages and disadvantages, and your physician will help you determine which is most appropriate for you.
