Thyroid disease: common in women

The thyroid is a gland in your neck, which produces hormones which are essential to life. These hormones are involved in many aspects of metabolism, including temperature regulation, and regulation of the way in which the heart beats.

There are two main types of thyroid disease, hypothyroidism, where the thyroid gland produces too little of the hormones, and hyperthyroidism, where it produces too much.

Hypothyroidism

In most cases, hypothyroidism is a result of problems in the thyroid gland itself, in which the gland simply doesn't produce enough of the hormones.

This can be caused by an automimmune disorder, in which the body attacks its own thyroid, or as a result of thyroid surgery, or radioiodine treatment for a hyperactive thyroid. In about 5% of cases, the problem lies in the parts of the brain, the hypothalamus and pituitary gland, which regulate hormone production.

What are the symptoms of hypothyroidism?

The main symptoms are lack of energy, constant tiredness, constipation, abnormal sensitivity to cold, muscle cramps and stiffness, weight gain, dry skin and hair, hair loss, and a hoarse voice. A slow heart rate, and sometimes psychiatric symptoms, such as depression, are also found.

If hypothyroidism is not treated, then myxoedema can appear, which is a cluster of symptoms including a dull, expressionless face, thin hair, puffy eyes, large tongue, and a thick, cool skin. This condition is very serious and needs to be treated urgently.

Hyperthyroidism

This is where the thyroid produces too many thyroid hormones. This is usually due to a problem with the thyroid gland itself. The most common causes are Grave's Disease, which is an immune system disorder, and benign thyroid tumours, which secrete more thyroid hormones than usual. Very rarely, hyperthyroidism can be caused by problems with the pituitary gland.

Symptoms of hyperthyroidism

The main symptoms are nervousness, insomnia, dramatic mood swings, tremors and shakes, increased heart rate, frequent bowel movements, weight loss in spite of increased appetite, and feeling hot all the time. People may also suffer from muscle weakness, shortness of breath, and palpitations. In women, the periods may become less frequent, or stop altogether. Older patients may suffer from heart failure or angina.

When caused by Grave's Disease, hyperthyroidism may cause protruding eyes, called exopthalmos.

Diagnosis of thyroid disease

Either hypo- or hyperthyroidism will be suspected from the history and physical examination. The diagnosis is based on the results of blood tests which measure the levels of the hormones produced by the thyroid, and the levels of a hormone which stimulates production of thyroid hormones, thyroid stimulating hormone (TSH). In some cases, the rate at which the thyroid takes up radioactive iodine is also used. In patients with thyroid tumours or thyroid nodules, a fine-needle biopsy is also performed.

Treatment

True thyroid disease cannot be treated by lifestyle changes, or alternative medication.

Treatment of hypothyroidism

This is treated by replacing thyroid hormone. There are many synthetic forms available. Your blood levels of thyroid hormones will be measured regularly to make sure that you are on the correct dose.

This treatment continues for life.

Treatment for hyperthyroidism

Hyperthyroidism can be treated with anti-thyroid drug therapy, which blocks the formation of thyroid hormones. Beta-blockers are also used to control the symptoms.

Radioactive iodine therapy is the most effective treatment, and is used to prevent the thyroid continuing to produce too many hormones. It is a quick and effective treatment. However, between 40 and 70% of people develop hypothyroidism as a side effect of the treatment within ten years. This is easily treated.

Conclusion

Thyroid disease is a relatively common problem, and particularly common in women. However, beware of assuming that problems with your thyroid are the only reason for tiredness or weight gain. If your thyroid hormones are normal, even if the values lie at the top of bottom end of normal, you do not need treatment. Your doctor should be looking for other reasons for your tiredness, and you should try a combination of diet and exercise for weight gain!