Blood results (serum free T4 level): I had a... - Thyroid UK

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Blood results (serum free T4 level)

Hibichan profile image
Hibichan

I had a blood test and my serum free T4 level and the original result was 10.3 pmol. I was tested again (three weeks after the first one) and now it is at 9.7 pmol.

Is this better or worse? It's so confusing. What does it mean?

Thank you

27 Replies

Assuming that the ranges were the same for both tests, I'm afraid it's worse. It's gone down. Do you have the ranges, please?

Hibichan profile image
Hibichan in reply to greygoose

Thank you for replying. I was looking and also there isn't much in it I couldn't tell if that was good or bad like which way it had gone haha.

The ranges are [9.0 - 20.0] and are the same for both tests.

greygoose profile image
greygoose in reply to Hibichan

Admittedly, it hasn't gone down by much, but the question is: is this just normal variation or is it a trend? You'll only know when you have your next blood test. It could go up again.

In any case, they're both very low in range, and show that you are under-medicated.

Hibichan profile image
Hibichan in reply to greygoose

Yeah exactly. That's why I wanted to check which way it had gone. I'm not on any medication because according to my doctor 'It's just anxiety' but hopefully this will push him to take it a little more serious and listen to me.

greygoose profile image
greygoose in reply to Hibichan

I hope so too. Anxiety is not a disease, it does not cause symptoms, it IS a symptom - very often a symptom of hypo.

Hibichan profile image
Hibichan in reply to greygoose

Yeah exactly. I was wondering for a while if something was causing my anxiety and then it all started to click in to place when I was looking in to the possibility of it being connected to my thyroid. But he keeps saying 'They are not thyroid symptoms they are anxiety symptoms' but I think they just hope that we'll go 'Ok doctor' and then just muddle on forward. It's so frustrating. I'm so glad I found this group though, so many posts are really relatable and makes me feel more 'normal' and how to move forward x

greygoose profile image
greygoose in reply to Hibichan

Doctors know nothing about thyroid symptoms. They don't learn about them in med school. He's just bluffing his way through, like they all do. Sigh.

They are so similar! My form says the range is [12.0 - 22.0] so you are in range either way (Edit oops not in range but again depends on TSH etc)

My last Free T4 result was 14.9 which they advised is really good (as it is going in the right direction and now in range) so your result is only relative to your and your other TSH and T3 results, we can't say if they are good or bad as it depends on what your doc is aiming for and to your personal situation! :D

tattybogle profile image
tattybogle in reply to kittyelen

kittyelen The lab range differs for fT4 tests done at different labs , so you can only interpret results with the range that came with the test.. Your lab has equipment that uses a [12-22] range , but looking at previous post, hibichan's lab uses this range :-

"Serum TSH level 6.08 mu/L [0.35 - 5.0]

Above high reference limit

Serum free T4 level 10.3 pmol/L [9.0 - 20.0]

If not on thyroxine, TFTs suggest possible subclinical hypothyroidism"

Hibichan , The difference in FT4 result between 10.3 and 9.7 [9-20] shows the doctor that your T4 (thyroid hormone ) has fallen a little lower than last time , which helps you with getting the Doctor to start treatment. However the difference is very small, and T4 varies a little within each day so your level of T4 might not actually be any worse than your first result was.

If your TSH has also risen a little from the previous 6.08 , that will also help to persuade them to start Levo.

What was TSH result this time ?

kittyelen profile image
kittyelen in reply to tattybogle

oh yeah sorry I miss read yours are just below the range but not by a massive amount oops I hope your doc explained things, so are they looking to start you on some meds?

tattybogle profile image
tattybogle in reply to kittyelen

the fT4 is not below the range , the range is [9-20] , so 9.7 is still just within range . (assuming hibichan had them done at the same place as the previous test....if it was done somewhere different we don't know what the range is because she hasn't replied yet)

kittyelen profile image
kittyelen in reply to tattybogle

ooh that is confusing the ranges on my blood form are different Serum free T4 level [12.0 - 22.0] mine was done in the UK NHS test so do private clinics have different guidelines?

tattybogle profile image
tattybogle in reply to kittyelen

confusing, yes , but it's not the treatment guidelines that are different.. all labs have slightly different ranges, even NHS ones. it's mostly to do with using different machines, and a little bit to do with local population adjustments. Basically if you sent the SAME blood to different lab's you might get fT4 15 [10-20] and to another lab you would get 17 [12-22], and another one would give you 11 [8-14]..... but all are the SAME result ie. 50% of the way through the range.

So that's why we always have to ask for the ranges that came with the test .

Hope that makes sense :)

Hibichan profile image
Hibichan in reply to tattybogle

It was done at the same hospital so ranges are the same :-)

Hibichan profile image
Hibichan in reply to kittyelen

Nah my doctor just keeps saying it's anxiety so I made him run tests again so he'll probably say it's anxiety again so just wanted to check if it was worse or better as it's really confusing for me haha. But I'm still waiting for more results to come back and then I'll speak to him again. They should come back today hopefully

Hibichan profile image
Hibichan in reply to tattybogle

Thank you for explaining that. Yeah hopefully it'll persuade him to do something. He keeps putting it down to anxiety and I know when I'm experiancing anxiety and when it's something else. But yeah, it was done at the same place. The new TSH result is 5.57 and before it was 6.08

tattybogle profile image
tattybogle in reply to Hibichan

Oh ,that's unfortunate , if TSH had risen it would show trend of worsening hypothyroidism, but now it's gone down a bit it is not so convincing to start treatment. Have they ever tested for thyroid auto-antibodies TPOab (thyroid peroxidase antibodies) ?... an over range result on these shows an autoimmune cause for subclinical hypothyroidism, and an increased probability that you would eventually become overtly hypothyroid, so that can help persuade them to treat earlier.

Also what time of day were both these TSH test's done ? TSH is naturally higher in the early morning and falls throughout the day lowest around 2pm ish.

Edit * in case that's all too depressing . i just wanted to let you know .. i was very similar to you . Got slowly more knackered after a baby , 5 yrs later it got really bad, i was really struggling to keep up with work , and housework, and social life was a no -no......went to GP ,had usual " it's just depression" conversations for several months, which i knew it wasn't.

1st test..............TSH 5.7 ......TT4 94 [65-155] (Total T4 is a different test to Free T4)

6weeks later.... TSH 6.8......TT4 91 [65-155]

Tested TPOab...... 2499 [0-50] .......GP said "Oh .. i see" and started Levo.

But if it help your confidence any , i know from experience how dreadfull you can feel with TSH at 'just' 5/6ish,,, and it's possible you currently have less actual thyroid hormone (T4) than i had at that time, so you are possibly in a worse state than i was... When talking to GP emphasise how low your fT4 results are, they are only barely inside the lower end of the range, and emphasise they have got lower since first test .. he may not even know they fluctuate ... we know a lot of thing on here that GP's don't :)

This graph of the most common 'healthy' TSH levels may also help your confidence that you are correct in suspecting hypothyroidism is causing your problems ( even if it is currently only classed as 'sub-clinical' :-

healthunlocked.com/thyroidu... as you'll see ... no one healthy has TSH of anywhere near 6.. most are around 1 or 2.

'Sub clinical hypothyroidism' ... this is what you are classed as at the moment ie. TSH over range but fT4 still within range (just!) Current NHS N.I.C.E Guidelines say GP's MAY CONSIDER treating at this point if symptoms of hypothyroidism are a problem, as long as they have two over range TSH results 3 months apart.

Hibichan profile image
Hibichan in reply to tattybogle

The recent one was early in the morning and the first one was a bit later in the day. I was asking for him to look in to it being caused by an autoimmune disorder as my Dad has coeliacs disease. And he was like 'Ok we'll test for coeliacs' so I'm waiting for that to come back and then will try to push it further either way x

tattybogle profile image
tattybogle in reply to Hibichan

Have *edited my previous reply ....OK, so if last TSH test was later in the day .. that explains why it's lower... if GP say 's it 'better than it was' tell him it's lower because it was taken later in the day , and if it had been taken earlier A.M. like previous one it would have been a bit higher than 5.57.

Edit* i'm wrong , recent test was EARLIER, so that argument won't work, sorry. x

Strong family history of autoimmune disease .. so make sure he Tests for thyroid autoantibodies (TPOab) as well as coeliac... having one autoimmune disease increases chances of having another , but most men don't ever get hypothyroidism.

Easy way to understand TSH and fT4 ....

Think of TSH and T4/3 on opposite ends of a see-saw.

As T4/3 go lower.. TSH goes higher.

As T4/3 rise ......TSH goes lower.

TSH (thyroid Stimulating Hormone ) is a message from the pituitary to the thyroid to ask for more or less thyroid hormones (T4/3) to be produced.

A high number like 10 means " more T4/3 please".

and a lower number like 0 means " we've got enough already . stop production of T4/3"

Hibichan profile image
Hibichan in reply to tattybogle

Ahhh, thank you so much for explaining :-)

tattybogle profile image
tattybogle in reply to Hibichan

LOL i must need more coffee or better glasses, i misread your earlier reply re. time of recent TSH test so i've edited that response as well.

Hibichan profile image
Hibichan in reply to kittyelen

At the moment my doctor is putting all my symptoms to being anxiety. I had bloods done a few weeks ago and then I spoke to him again because I felt worse so he reluctantly sent me off for more blood tests. This time it was a fasting one as he wanted to test for glucose as well. He also did a few tests he hadn't done before.

It says the range on mine is [9.0 - 20.0]

SlowDragon profile image
SlowDragonAdministrator

Previous post

As your Dad has coeliac (autoimmune) you need to get FULL thyroid and vitamin tested....privately if GP is difficult

Just testing TSH and Ft4 is completely inadequate

Previous post shows slightly low vitamin levels.....presumably you have been working on improving these

Essential to test thyroid antibodies and coeliac blood test

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested.

Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins

List of private testing options

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Thriva Thyroid plus antibodies and vitamins By DIY fingerpick test

thriva.co/tests/thyroid-test

Thriva also offer just vitamin testing

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

bluehorizonbloodtests.co.uk...

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

If TPO or TG thyroid antibodies are high this is usually due to Hashimoto’s (commonly known in UK as autoimmune thyroid disease).

About 90% of all primary hypothyroidism in Uk is due to Hashimoto’s. Low vitamin levels are particularly common with Hashimoto’s. Gluten intolerance is often a hidden issue

Link about thyroid blood tests

thyroiduk.org/getting-a-dia...

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

List of hypothyroid symptoms

thyroiduk.org/if-you-are-un...

Hibichan profile image
Hibichan in reply to SlowDragon

My doctor is still being difficult. I explained everything and he was like 'Fine, I'll run bloods again but it's just anxiety'. So I was testing at the same hospital as before and he also did a test for helicobacter pylori antigen which came back negative.

So the first test was

Renal function tests

Liver function tests

Bone profile

Fasting blood glucose level

Serum TSH level

Serum free T4 level

Serum C reactive protein level

Erythrocyte sedimentation rate

Full blood count

which I recieved my results for yesterday.

And I explained my Dad's coeliac's and he was like 'Well fine, we'll do a blood test for that as well to rule that out'

So I had bloods drawn for Coeliac (TG IgA) but the results aren't back for that yet.

So when that's in as well then I'll speak to him again and see what he says and push for any other tests I might need or look in to getting them done privately.

It's so frustrating because he speaks to me like I'm an idiot. Like in a kind of *pats head* 'You have anxiety and that's all so shhhh' kind of way.

But atleast tests are being done now and I'm glad I found you all here as it really does make it easier.

SlowDragon profile image
SlowDragonAdministrator in reply to Hibichan

Anxiety is common hypothyroid symptom

Thousands of members have had similar difficulties getting diagnosed

Hibichan profile image
Hibichan in reply to SlowDragon

I read about that. He keeps putting my symptoms down as anxiety and I queried the possibility of the anxiety being a symptom of a thyroid issue and he didn't seem to have an answer to that one.

Thanks for your help :-D

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