36 year old male based in England here. I posted last week about my frustration of being refused at least a trial of treatment following blood test results which showed a TSH of 4.7. I have experienced debilitating symptoms of fatigue, depression, brain fog, cold intolerance and weight gain for the last three years, whilst my TSH results had steadily risen year by year.
Only now have I had the full spectrum of blood tests done, and I have just received another result back for something’s I had missed (FT3, TG antibodies etc). These results read:
TSH - 4.9
FT4 - 18.9 pmol/l [12 - 22]
FT3 - 5.2 pmol/l [3.1 - 6.8]
TPO Antibodies - 13.4 IU/ml [0 - 34]
TG Antibodies - 12.6 IU/ml [0 - 115]
At this point, I’m confused. Part of me had expected FT3 to be low for some reason, but that along with everything else seems normal. Why though, if everything else is normal would be TSH be raised in the first place and why would I be experiencing all of the classic hypothyroid symptoms?
Is it worth testing RT3. I have read up a little on this, in particular in situations where a significant amount of weight loss has occurred (I dropped about 6 stone, 40% of my original weight) in 2016/17 - intentionally that is. However, I haven’t been able to work out whether or not theories on RT3 is quack science or not.
I am seeing another specialist next week, a doctor who is herself a sufferer of hypothyroidism and is prepared to prescribe NDT where the results indicate a necessity. However, would a high TSH only be such a case?
Feeling a little confused and exhausted. Thanks!
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JonnyA
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I remember your last post, I replied to it and tried to explain a few things. I'll try again.
Why though, if everything else is normal would be TSH be raised in the first place and why would I be experiencing all of the classic hypothyroid symptoms?
I'm not sure how much you know about the workings of the thyroid, but you don't see to have quite grasped how the TSH works.
Thyroid Stimulating Hormone, produced by the pituitary when the pituitary senses that there's not enough thyroid hormone in the system - T4 and/or T3.
A euthyroid TSH is around 1. Never over 2. And at 3 you are hypo.
So, a euthyroid person has a TSH of around 1 which keeps their euthyroid FT4 and FT3 at around mid-range - the FT3 is usually slightly lower than the FT4 in their respective ranges.
To get the same results in FT4/3, you need your TSH at 4.9, which is a hypo TSH, not a euthyroid TSH.
So, your TSH is telling us that your thyroid is failing, and is having trouble producing the right amount of thyroid hormone.
So, what do the Frees tell us?
Your FT4 is somewhat on the high-side, which - although in-range - is higher than we would normally see.
Your FT3 is around a euthyroid level - 'normal'.
But to get your FT3 to a 'normal' level, you need to have a high FT4, which is not 'normal'.
This tells us that you don't convert very well.
In summary: you need a high TSH and a high FT4 level to get your FT3 to a euhyroid level. T3 is the active hormone, needed by every single cell in your body, and too little of it causes symptoms, because without it, the cell cannot function properly. And your thyroid is struggling to produce enough of anything. So, not surprising you have symptoms.
Is it worth testing RT3.
No, it isn't. It's an expensive test and won't give you any information that you can't get elsewhere.
rT3 is not the problem. It is inert and only stays in the body for a couple of hours before being converted into T2, then T1, then the iodine is reused by the body.
It's the body's safety valve, to stop you going hyper or having too much T3 at inappropriate times. And, at the same time, recycles excess T4.
There are many, many causes of rT3 and only one of them has anything to do with the thyroid. And, that is when the FT4 is too high. Your FT4 may or may not be too high for you - we don't know, everyone is different - but it doesn't matter, anyway, because rT3 is never the problem.
I haven’t been able to work out whether or not theories on RT3 is quack science or not.
Not 'quack' science, no. Just not up-to-date. It used to be thought that rT3 blocked the T3 receptors, but it has now been discovered that rT3 has its own receptors.
You might find this thread interesting on that subject:
I am seeing another specialist next week, a doctor who is herself a sufferer of hypothyroidism and is prepared to prescribe NDT where the results indicate a necessity. However, would a high TSH only be such a case?
I think it would. As you have so many symptoms, you would hopefully find relief in raising your FT3. Obviously, it wouldn't be much use taking levo, because you're not short on T4 at the moment - although you probably will be, eventually - but raising the FT3 would probably be beneficial and take the strain off your thyroid. Worth a try at the very least.
Thank you for taking the time to post that and for enhancing my knowledge - I’ve tried to learn as much as I can but clearly my understanding isn’t quite there yet.
If I understand your comments correctly my free levels are normal but sub-optimal, despite a high TSH level (ergo my body is working extra hard just to achieve relatively poor (if technically normal) free levels). On that basis, a combined T4 and T3 based treatment is likely to help improve my symptoms.
Not 100% correct, no. That's not exactly what I said. I wasn't talking about optimal. Optimal is what you feel, not a number. Your results could possibly be optimal for some people, but obviously not for you. We're all different, so I avoid talking about optimal.
And I try to avoid the word 'normal', because it doesn't mean much. Let's just say that your results are 'in-range'. But, obviously, that doesn't mean much, either.
And your levels are where they are BECAUSE of the high TSH, not despite it.
But you're right in that your pituitary and your thyroid are having to work extra hard, just to stay afloat.
But, yes, I do agree that NDT is likely to help improve your symptoms. And, in the end, that's what counts.
Sorry to drag this up again - I’ve just been going over your original reply to make sure that I’m as clear as possible on everything before I see my doctor. One more question sprang to mind.
From what you’ve said, my FT3 levels are normal. Yes, my TSH has had to become raised in order to get there, but they are normal all the same.
Given that, why would I still be experiencing symptoms?
Sorry for yet another question, I just found your responses really helpful.
Well, that brings us back to the discussion about 'what is normal'. They are in-range, for sure. But, are they 'normal' for you? And, that we can never know, because thyroid hormone levels are never tested when you're healthy.
One thing we do know is that hypos tend to need higher levels of thyroid hormone than euthyroids. A euthyroid FT3 would probably be just under 50% through the range - give or take a few percent, because we're all different. But the majority of hypos need their FT3 higher than that - say around 75% and up - even sometimes slightly over-range. So, on that basis, we would say that your level is not high enough for you, and that's why you have symptoms.
You have to understand that ranges are just averages, they are not set in stone. They are arbitary at best, just a guide to back up your symptoms, and should not be taken too literally. And, the way they are derived is often suspect. You might be interested to read this article posted by helvella some time ago, which explains it nicely:
The normal range: it is not normal and it is not a range
1. Martin Brunel Whyte
2. Philip Kelly
Abstract
The NHS ‘Choose Wisely’ campaign places greater emphasis on the clinician-patient dialogue. Patients are often in receipt of their laboratory data and want to know whether they are normal. But what is meant by normal? Comparator data, to a measured value, are colloquially known as the ‘normal range’. It is often assumed that a result outside this limit signals disease and a result within health. However, this range is correctly termed the ‘reference interval’. The clinical risk from a measured value is continuous, not binary. The reference interval provides a point of reference against which to interpret an individual’s results—rather than defining normality itself. This article discusses the theory of normality—and describes that it is relative and situational. The concept of normality being not an absolute state influenced the development of the reference interval. We conclude with suggestions to optimise the use and interpretation of the reference interval, thereby facilitating greater patient understanding.
dx.doi.org/10.1136/postgrad...
So, I really think it would be best to drop that stupid word 'normal', it's meaningless!
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