DR MIRIAM: Should I trust thyroid test? LETTER OF THE DAY.

Byline: MIRIAM STOPPARD

DEAR MIRIAM,

FOR years I've been feeling tired. I've complained about it to my GP many times and I've always been told everybody feels that way.

I know I have a slow pulse and decided to check my other symptoms on the internet, including irritability, being very sensitive to cold, weight gain, poor memory and concentration, and a croaky voice. The results came up with hypothyroidism.

I returned to my GP with this information and my doctor said my blood tests results were normal so there's nothing wrong with my thyroid.

Do you agree that a person could have blood-test results that are normal and still be suffering from sub-clinical hypothyroidism?

THE term sub-clinical simply means a patient isn't displaying the full complement of symptoms normally found in a particular condition.

This happens quite often in hormonal conditions, particularly the menopause.

It's possible for a woman to be experiencing quite profound menopausal symptoms but for her blood test to come back as normal.

It's important to understand there's nothing wrong with the test - a mistake hasn't occurred. The reason is that hormone levels decline gradually, but for some the effects are felt long before they reach a quantifiable reduction.

Where thyroid disease is concerned, the blood test is still the best diagnostic tool we have.

Nothing else reveals as much information about how the thyroid is behaving. But when the test can't guide us through the sub-clinical state, it's up to the doctor's judgment what to do next. Frankly, no two doctors may agree about the same set of symptoms.

You may think the answer is to ask your GP to treat you for a condition you may well be in the process of developing, and this is a strategy I would recommend as far as the menopause is concerned, but I'm afraid that it doesn't work when it comes to the thyroid.

No doctor can ethically prescribe the thyroid hormone unless they know (not think, not presume, but know) there is an inadequacy.

It all comes down to doing what's safe. Too much of the thyroid hormone is dangerous because it has serious health implications for your heart and other parts of your body.

Waiting is safe. It may not be fun, it may make you feel very despondent, but it will not hurt you.

I have a personal anecdote that may illustrate this. I go for an annual health check and one year I was told my thyroid level was a bit on the low side and I should have it checked out. I meant to but did nothing because life was busy and I just didn't make the time.

The following year it was a bit lower and again I was told to see a specialist but life was even more hectic and I never got around to it.

When my thyroid test was very low for the third time, I went to the specialist. The result is I'm now on medication and will be forever.

But throughout all this I was writing my Daily Mirror column and numerous books, leading an active life, going on holiday, visiting grandchildren and getting on with the usual routine.

It was making me more tired but delaying the treatment did me no damage.

The first rule of the ancient Hippocratic oath is do no harm. A doctor would be betraying that principal if he or she prescribed without knowing for sure you were in need of it.

CAPTION(S):

TIRED: Symptons include a low pulse rate