30 January 2012

When there’s a lack of thyroid hormone in the body (hypothyroidism), you could suffer fatigue, weight gain, depression, constipation, muscle cramps, and high cholesterol levels.

A FORTNIGHT ago, I read your article about hyperthyroidism. I have the exact opposite problem. I gain weight easily, feel very tired all the time, and people have complained that I am very slow. I tested my blood, and the doctor says I have hypothyroidism. What is this?

Hypothyroidism is the opposite of hyperthyroidism. This is a condition that occurs when your thyroid gland produces less thyroid hormones (thyroxine) than your body needs.

Thyroid hormones, as we have discussed, are essential in maintaining our body’s metabolism. They affect our breathing, brain development, heartbeat, nervous system, body temperature, muscle strength, skin dryness, menstrual cycles and weight.

So you can imagine that if we have low levels of them, all of the above will be affected negatively.

Hypothyroidism is more common than you think, so you are not alone. It affects 3% to 5% of our population. Unfortunately, most people don’t recognise it, and are labelled “old”, or “slow”.

When you get older, you are more likely to get it. It also happens more often in women than men.

What causes hypothyroidism? It’s not cancer, is it?

Thyroid cancer almost never causes hypothyroidism, because it’s rare that the cancer is so widespread that it destroys all your thyroid cells.

More commonly, the causes are:

> Hashimoto’s thyroiditis – there is a goitre associated with this, and it is an inherited autoimmune condition. This means that your body’s own defence cells attack your thyroid gland cells.

If one of your family members has this, you are more likely to get it too. It’s extremely common in Western countries.

> Thyroiditis following hyperthyroidism – this is a condition that is quite common after pregnancy. It affects up to 8% of women after they deliver. In here, your thyroid gland becomes inflamed.

Thyroid hormones actually leak out of your inflamed thyroid gland and cause hyperthyroidism for a brief spell.

After the leakage stops, you go into a hypothyroid phase instead because your inflamed cells reduce production of the thyroid hormones.

This phase usually lasts for six months or so. Most women usually return to normal.

> Destruction of your thyroid cells by surgery or radioactive iodine – when your thyroid gland has been removed or destroyed in any way because of cancer, Grave’s Disease (which causes hyperthyroidism) or a goitre that has become too huge to live with, it’s fitting that you no longer have that many thyroid cells left to produce thyroid hormones.

So you enter a state of hypothyroidism, and have to go on thyroxine pills the rest of your life.

> Pituitary or hypothalamic disease – this goes back to the signalling chemical of the thyroid gland, the thyroid stimulating hormone (TSH), that is produced by the pituitary gland, and governed by the hypothalamus.

So if anything were to affect the pituitary gland and hypothalamus, then you will get hypothyroidism.

> Medications for hyperthyroidism – these actually may cause the reverse: hypothyroidism.

> Iodine deficiency – in remote mountain areas (East Malaysia, for example), where you can’t get easy access to seafood, you may get iodine deficiency.

That’s why our bread is now fortified with iodine, provided you actually do get access to the bread.

How will I know if I have hypothyroidism?

The reason why most people don’t know they have hypothyroidism is because the symptoms of hypothyroidism are non-specific and easily confused with other diseases.

But do look out for fatigue, weight gain, depression, intolerance to cold, feeling sleepy all the time, your hair getting dry and coarse, your skin getting dry, constipation, muscle cramps, difficulty in concentrating, swelling of your legs, and increased cholesterol levels.

If severe, there may be puffiness around your eyes. Your heart rate may slow down, as will your body temperature. If untreated, this may lead to heart failure.

In its most severe state, especially when it is triggered by stress, surgery or injury, hypothyroidism can lead to coma.

Is there any hope for it to be treated?

Of course. The treatment is to take thyroxine, which comes in pill form. Most doctors will give you T4, a once a day medication, instead of T3, which needs to be taken multiple times a day.

This article was published in www.thestar.com.my on 16 November 2011.