useful 'Evidence' that TSH between 0.04 - 0.4... - Thyroid UK

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useful 'Evidence' that TSH between 0.04 - 0.4 has no increased risk to patients on Levothyroxine (UPDATED~new study does show small risk)

tattybogle profile image
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This paper forms part of the evidence base for the current NHS thyroid treatment guidelines , it was referenced as evidence to back up their concerns about "low TSH /overtreatment with levo/ risk to bones and heart"

( so they cannot say it is 'not good enough evidence' when you put it under their nose).

However when read carefully ,it actually says that 'low but not supressed' TSH 0.04 - 0.4 on levo had no greater risks than TSH 'in range' does . The risks did increase sharply when TSH was below 0.04 ...

SO .....you can use this paper as a very strong argument that TSH 'itself' is not a increased risk for Fractures / Dysrhythmias (Atrial Fibrilation) / Cardiovascular Disease .... AS LONG AS YOUR TSH is 0.04 or ABOVE .

It was a large, long term study of 17,000 real patients on levo in Scotland.

academic.oup.com/jcem/artic... Serum Thyroid-Stimulating Hormone Concentration and Morbidity from Cardiovascular Disease and Fractures in Patients on Long-Term Thyroxine Therapy

Robert W. Flynn, Sandra R. Bonellie, Roland T. Jung, Thomas M. MacDonald, Andrew D. Morris, Graham P. Leese

The Journal of Clinical Endocrinology & Metabolism, Volume 95, Issue 1, 1 January 2010,

"Abstract

Context: For patients on T4 replacement, the dose is guided by serum TSH concentrations, but some patients request higher doses due to adverse symptoms.

Objective: The aim of the study was to determine the safety of patients having a low but not suppressed serum TSH when receiving long-term T4 replacement.

Design: We conducted an observational cohort study, using data linkage from regional datasets between 1993 and 2001.

Setting: A population-based study of all patients in Tayside, Scotland, was performed.

Patients: All patients taking T4 replacement therapy (n = 17,684) were included.

Main Outcome Measures: Fatal and nonfatal endpoints were considered for cardiovascular disease, dysrhythmias, and fractures. Patients were categorized as having a suppressed TSH (≤0.03 mU/liter), low TSH (0.04–0.4 mU/liter), normal TSH (0.4–4.0 mU/liter), or raised TSH (>4.0 mU/liter).

Results: Cardiovascular disease, dysrhythmias, and fractures were increased in patients with a high TSH: adjusted hazards ratio, 1.95 (1.73–2.21), 1.80 (1.33–2.44), and 1.83 (1.41–2.37), respectively; and patients with a suppressed TSH: 1.37 (1.17–1.60), 1.6 (1.10–2.33), and 2.02 (1.55–2.62), respectively, when compared to patients with a TSH in the laboratory reference range. Patients with a low TSH did not have an increased risk of any of these outcomes [hazards ratio: 1.1 (0.99–1.123), 1.13 (0.88–1.47), and 1.13 (0.92–1.39), respectively].

Conclusions: Patients with a high or suppressed TSH had an increased risk of cardiovascular disease, dysrhythmias, and fractures, but patients with a low but unsuppressed TSH did not. It may be safe for patients treated with T4 to have a low but not suppressed serum TSH concentration.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This post deals specifically with the alleged risk to bones.. it links to a recent long term study of patients whose TSH was kept deliberately supressed with levo, long term ( to prevent recurrence of thyroid cancer) ..... it found no significant increase in bone loss with a long term supressed TSH as long as T4 was kept in range.

healthunlocked.com/thyroidu... longterm-subclinical-hyperthyroidism-does-not-affect-bone-density-in-patients-having-had-thyroid-ablation-for-cancer

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This very recent study (Feb 2023) shows that in euthyroid people over 50yrs old , a higher ratio of T3 to T4 is associated with a reduced osteoporosis / fracture risk. And that higher T4 levels are associated with increased risk ... which if you assume the same applies to those taking thyroid hormone, backs up the idea of giving a bit less Levo and adding a bit of T3 will REDUCE their risk of osteoporosis / fracture. ( i think ?.... it's a bit complicated to understand the results , but diogenes has clarified the findings in a reply to the post )

post discussing: healthunlocked.com/thyroidu...

direct link to paper: pubmed.ncbi.nlm.nih.gov/367...

thankyou            Mollyfan for finding it .

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For a list of links to other useful discussions on the subject of low TSH/ Risk vs Quality of life ,, please see my reply to this post ( 3rd reply down)

healthunlocked.com/thyroidu... feeling-fine-but-tsh-is-low

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

There are SOME CONCERNS that having high /over rage T4 promotes some kinds of CANCER CELL PROLIFERATION ~ recent research:

healthunlocked.com/thyroidu... levothyroxine-monotherapy-and-cancer

some replies in this post discuss the issue & provide links :

healthunlocked.com/thyroidu... /over-range-t4?

Update : recent video post from    jimh111 healthunlocked.com/thyroidu... thyroid-hormones-and-cancer-video

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If your GP says , "i have to reduce your dose , because i have to follow the NHS guidelines", then remind them of this bit , it's the first thing said to GP's ,on the first page of the latest NHS (N.I.C.E) guidelines for thyroid disease and management. nice.org.uk/guidance/ng145

" Guideline development process

How we develop NICE guidelines

Your responsibility

The recommendations in this guideline represent the view of NICE, arrived at after careful consideration of the evidence available. When exercising their judgement, professionals and practitioners are expected to take this guideline fully into account, alongside the individual needs, preferences and values of their patients or the people using their service. It is not mandatory to apply the recommendations, and the guideline does not override the responsibility to make decisions appropriate to the circumstances of the individual, in consultation with them and their families and carers or guardian. "

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

UPDATED : this very recent study being is being used (by Prof. Bianco) to show that a low TSH on Levo IS an increased risk factor for death from cardiovascular/ stroke EVEN WHEN fT4 is IN RANGE .

However it still needs looking at carefully to keep these risks in perspective . It has similar findings to the first study i posted above ...in that the risk was significantly less for low but not supressed TSH (0.1 - 0.5) than it was for supressed TSH (below 0.1)

healthunlocked.com/thyroidu... bianco-video? tattybogles reply.

I think this must be the study Prof Bianco refers to in his answer to the question about evidence of low TSH risk when fT4 is in range ? (fairly recent/ VA data/ half a million ish / TSH and fT4 risks looked at SEPARATELY / looked specifically at cardiovascular / stroke mortality ).

jamanetwork.com/journals/ja... Association of Thyroid Hormone Treatment Intensity With Cardiovascular Mortality Among US Veterans

Josh M. Evron, MD1; Scott L. Hummel, MD, MS2; David Reyes-Gastelum, MS3; Megan R. Haymart, MD3; Mousumi Banerjee, PhD4; Maria Papaleontiou, MD3,5

"The forest plot in the Figure illustrates the association between serum thyrotropin (TSH) and FT4 levels with cardiovascular mortality after adjustment for relevant demographic and cardiovascular risk factors.

Cardiovascular mortality was higher among patients with:

exogenous hyperthyroidism:

thyrotropin levels <0.1 mIU/L: AHR, 1.39 95% CI, 1.32-1.47;

thyrotropin levels of 0.1 to <0.5 mIU/L: AHR, 1.13 95% CI, 1.09-1.17;

FT4 levels >1.9 AHR, 1.29 95% CI, 1.20-1.40)

and those with exogenous hypothyroidism:

thyrotropin levels from >5.5 to <7.5 mlU/L : AHR, 1.42 95% CI, 1.38-1.46;

thyrotropin levels from 7.5 to <10 mIU/L: AHR, 1.76 95% CI, 1.70-1.82;

thyrotropin levels of 10-20 mIU/L: AHR, 2.13 95% CI, 2.05-2.21;

thyrotropin levels >20 mIU/L: AHR, 2.67 95% CI, 2.55-2.80;

FT4 levels <0.7 ng/dL: AHR, 1.56 95% CI, 1.50-1.63),

with risk increasing with higher serum thyrotropin levels compared with individuals with euthyroidism."

So ..... while it does indeed separate the risks for TSH (thyrotropin) and fT4 levels and it does show there IS a higher risk for low TSH ..... it ALSO clearly shows that the risk for TSH between (0.1 -0.5) is significantly LESS than the risks for TSH below 0.1

and LESS than the risk for over range fT4.

and LESS than the risk for slightly over range TSH (5.5 -7.5)

and LESS than the risk for below range fT4.

(AHR ~adjusted hazard ratio where AHR 1 = 'no extra risk' , AHR 0.5= 50% less risk, and AHR 1.5 = 50% increased risk .... so TSH (0.1- 0.5) AHR 1.13 = 13% more risk than TSH in range.

... or at least that is what i think AHR means , i'm not a statistician,, but i know AHR 1.13 is not much more risk than AHR 1 (no risk) ,and it's a lot less risk than AHR 1.56)

so that seems to roughly fit with the first Levo study in this post which found a low but not supressed TSH (0.04 -0.4) had no greater risks than in range TSH did.

I have other concerns/ questions about this study....

1) it doesn't appear to separate people into groups with (low TSH and high fT4) vs (low TSH with fT4 in range) because it looks at TSH and fT4 separately ... so do we know how many with low TSH also had high fT4 ?.. and therefore how do we know it wasn't the high fT4 increasing the risks for many of the subjects with low TSH ?

2) the study group was comprised of 88.7% men ... who are known to have a greater risk for cardiovascular disease than women .. so even though they say they have adjusted for sex etc .... is this really a good enough study to base treatment of women on ??

So personally, it hasn't changed my mind about the risks of running a low but not supressed TSH on levo if i need to ....yes there do seem to be some added risks, but they are significantly smaller than the risks of slightly undertreating hypo and no one seems to give two hoots about that being risky, and they certainly don't bother telling telling us we are risking death from it.

......So until i hear of GP's taking the OTHER risks equally seriously eg. panicking their Levo patients are going to die unless they increase dose when TSH is slightly over range at 5.7 because that risk is greater than having a TSH below 0.1

or insisting fT4 is always checked and sending everyone with a slightly below range fT4 off to the endo pronto because the risks of a below range fT4 are greater than that of TSH below 0.1 ........

......then , i'm not going to take their concerns about low TSH level very seriously either........... If they are flapping like headless chickens about one of the risks while blithely ignoring some others that are greater , they are obviously either biased ... or just to thick to interpret a study carefully for themselves.

The key point to get across to GP's in dose 'discussions' is that whatever the 'risks' associated with low TSH.. they need to be looked at in context of all the other risks that they don't seem half as bothered about ... most importantly in relation to the clear risks of feeling so unwell on a lowered dose that you don't get off the sofa very much .. which is definitely a BIG risk for heart health and bone strength.

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tattybogle profile image
tattybogle

Mainly sticking this here for my own reference to save me writing it out each time i need it.

diogenes profile image
diogenesRemembering in reply to tattybogle

As always, statistics shows the likelihood but not the individual certainty. Even accepting the findings, they should not hamper the individual patient in making their own decisions in their own circumstances. I would have no quarrel with this, if the findings were placed honestly and not luridly to the patient on presentation. Based on these findings, it should NOT be the case that one is told "your TSH is too low therefore you're going to have heart and bone problems". The likelihood is the expression to convey to a patient. This gives the patient a choice: reduced QoL over life or slightly less lifetime. In addition , " by how much does this add to likelihoods of the same diseases from all causes?" It's a case of potential dictation to patients as to how their lives are to go henceforward.

tattybogle profile image
tattybogle in reply to diogenes

Thankyou Diogenes.

Josephineinamachine profile image
Josephineinamachine in reply to tattybogle

Couple years ago I actually felt pretty rubbish with suppressed TSH even when my T4 and T3 were in range. Lowered slightly. T4 and T3 didn’t shift much but TSH no longer suppressed and felt much better 🤷🏻‍♀️

tattybogle profile image
tattybogle in reply to Josephineinamachine

me too josephineinamachine :) i did OK with TSH 0.05 ish for many years , with T4 ranging between 60% and 130% (on Levo )

I later became overmedicated on the same dose, ( following menopause) with symptoms of overmedication which were not entirely classic but made me feel absolutely bloody awful .

My TSH at that time had fallen slightly to 0.018... my fT4 at the time was about 120%,, but it had been at that level before without any unpleasant symptoms , sadly no info on fT3 so not very enlightening .

a dose reduction resolved the symptoms i was having .ad TSH went back to it's usual 0.05ish

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

~ NOTE FOR EVERYONE ~

This post is NOT a recommendation to HAVE these levels of TSH on Levo ... it will be to low for some people , and some people will experience symptoms of overmedication at these levels of TSH even if their T4 /T3 are still in range.

~ "closer to 1 " is a much better place to 'aim' for initially.

This post is A TOOL for the use of people who feel properly well with TSH at these low levels and have tried a lower dose (properly, for AT LEAST 2 months) ,and found it reduced their quality of life to an unacceptable level .... but their GP is insisting on the the "low TSH risk means i HAVE TO reduce your dose anyway " line .

jimh111 profile image
jimh111

I've quoted this paper a number of times. First, we should note that the 0.04 cutoff is arbitary, they could have chosen 0.03 or 0.05 or something quite different. So, 0.04 isn't a cliff edge between safe and unsafe, it's a matter of degree.

Fig 2 academic.oup.com/view-large... is useful. It shows that while a TSH of 0.04 isn't bad a TSH around 1.0 is better. Other studies show that higher normal TSH is safer from a cancer and heart disease perspective - because it is associated with a lower fT4.

Also, note that a mildly elevated TSH, around 5.0 - 10.0 carries a much higher cardiovascular risk than a TSH around 0.04. Just waiting to hear doctors telling us that 'subclinical hypothyroidism' is so dangerous.

tattybogle profile image
tattybogle in reply to jimh111

Absolutely agree jim ...0.04 is totally arbitrary ... and ignores the individual as usual ~ i don't beleive it proves 0.04 is fine and 0.03 means "yo gona die" ....i just find this paper useful as pretty bombproof evidence to shut a GP/ endo down , if you happen to have "0.04 or over"

My last link to "other useful discussions" does includes a bit about why highish fT4 is not desirable if it can be avoided with a link to you posts on that subject .. but it's a bit convoluted to get there , so if you want to add a more direct link here, please do.

indeed ~ how bad can those 'increased risks' for TSH below 0.04 really be ...... they were sharply increased true , but most of them were still not as bad as the risks for TSH 7/8/9 and "no GP EVER" has been heard to give a monkeys about THOSE risks ... funny that .

TSH110 profile image
TSH110 in reply to jimh111

good point, my heart pains were at their zenith on Levothyroxine with high t4 and very low T3 and quite low but not supressed TSH

DippyDame profile image
DippyDame in reply to jimh111

note that a mildly elevated TSH, around 5.0 - 10.0 carries a much higher cardiovascular risk than a TSH around 0.04.

Is this not because the higher TSH indicates that the patient is hypothyroid/undermedicated and the low hormone level causing this is a reflection of the low hormone state in the serum which has the potential to cause cardiovascular risk....and that low hormone is likely to be T3 which the heart needs in some quantity

TSH however cannot indicate which hormone is low and surely that is the crucial point....it is an unreliable marker.

So why don't they test FT3 routinely as used to happen (at least in my surgery)....and cut to the chase!

jimh111 profile image
jimh111 in reply to DippyDame

Usually it is fT4 that is low and fT3 is maintained by proportionally more T3 secretion and T4 to T3 conversion. It does show that even mild hypothyroidism increases cardiovascular risk.

DippyDame profile image
DippyDame in reply to jimh111

My point was more to do with the focus on TSH as a marker ...rather than on the actual thyroid levels!

To quote Tania Smith...

Low thyroid hormone levels, not necessarily high TSH, “should therefore be regarded as a cardiovascular risk factor.”

If the body has to work hard to maintain FT3 level is it not an indication that the thyroid is failing..... the body ramps up its conversion to keep T3 levels as high a it can for as long as it can.

If that cannot be maintained then FT3 will drop and there will eventually be an increased risk cardiovascular risk....

In other words the focus on TSH is unreliable....ignoring FT3 is surely the risk

jimh111 profile image
jimh111 in reply to DippyDame

Usually with a mildly elevated TSH it is fT4 that is lowish. It is not known how much T3 the heart gets from circulation and how much from type-2 deiodinase (T4 to T3 conversion). It may be that the lower circulating T4 is the reason the heart has problems, not enough to convert to T3 within the heart. So, measuring fT3 may not be very helpful in this circumstance.

Unfortunately, TSH is the only widely available measure for these types of studies.

DippyDame profile image
DippyDame in reply to jimh111

So we all sit back and accept a status quo that fails patients!

TSH is clearly not the gold standard we are told it is.....but without the will to advance things we are stuck

Where are the thyroid scientists working to eliminate some of the if and buts and may bes.

Ah! But they need financial backing and this isn't seen as a priority.

So we bungle on....

To quote diogenes in his article for TUK "The History of Thyroid Testing"...

"For the moment mechanical thinking has traduced medical diagnosis."

I rest my case!

TSH110 profile image
TSH110 in reply to jimh111

but isn’t the nub of the problem that the body is proritising t3 because of a lack of thyroid hormones to go round, if it let t3 fall but tried to keep t4 up it would be an even more disasterous outcome for the sufferer. Getting them resolved would stop it all if you supplied some t3 the thyroid would get an immediate rest - it must be whacked pumping out all that t3.

I’m not sure I believe peripheral production is of much relevance, is it anything more than super fine tuning?

tattybogle profile image
tattybogle in reply to TSH110

unscientific comment from a cabbage brained scarecrow ... why would making T3 be any 'harder' for the thyroid than making T4 ....it's probably 'easier' for it to make T3 cos it only has to stick 3 bits of iodine together instead of 4 .

TSH110 profile image
TSH110 in reply to tattybogle

mm but if it’s not really designed to pump that level out all the time it might be a bit much, but it’s a good point perhaps it’s actually having a holiday!

jimh111 profile image
jimh111 in reply to TSH110

Going from memory peripheral T3 production (conversion from T4) accounts for about 80% to 85% of T3 in healthy people. The brain in particular is especially reliant on conversion of T4 to T3. All this seems to depend on adequate bioactive TSH to stimulate the T4 to T3 conversion. I discuss it here ibshypo.com/index.php/type-... .

Take a look at the last study by Bianco as it shows how when relying on T3 only the brain needs 3x the normal level of T3 in the blood to restore normal brain function. Note these experimental rats were healthy with normal TSH function.

If you give primary hypothyroidism patients T4 only they need a higher fT4 (which carries risks) and a lower TSH to achieve typical fT3 levels. This lower TSH reduces D2 activity and so these patients are more likely to suffer cognitive problems. The DIO2 rs225014 polymorphism makes this a bit worse.

TSH110 profile image
TSH110 in reply to jimh111

thanks for that clear explanation. I’ve got that polymorphism but just one allele not two but my conversion was very poor. Endo aimed for low TSH of 0.2-0.5. My thyroid atrophied to a crisp so it has no function (according to endocrinologist’s comments on the ultrasound exam). NDT made a huge difference to my well-being. I always felt very unwell on Levothyroxine 120/125 alternating. If I took more I just felt crazy. Only needed 1.25 grains of NDT but have had to up it to 1.75 over the years, no idea why. Does the body become accustomed to it and eventually demand more for the same result?

jimh111 profile image
jimh111 in reply to TSH110

Can’t answer your last question but a lot of people need a higher T3 / T4 ratio than normal.

Jeppy profile image
Jeppy in reply to DippyDame

🤔because some areas don't it's a postcode lottery - expense being operative word

DippyDame profile image
DippyDame in reply to Jeppy

Understood....but that needs to change and accepting the status quo won't change anything!

Jeppy profile image
Jeppy in reply to DippyDame

def. But worn thin as hands are tied

Endo just sent a letter to say just up my 5omg levo even though I'm in 125!!! And is dismissing me now. Even though TSH is. 4.4.! (In fact all my numbers are as they were b4 ANY levo!?)

Basically had 3 appointments cancelled over 3 yrs, appalling and saddened and they don't like me as I wrote I'd like to try t3 He has written in Bold print 'there is only one thyroud medication'!!!

Speechless and feel powerless

Excuse rant x

tattybogle profile image
tattybogle in reply to Jeppy

Rant allowed Jeppy

"there is only one thyroid medication" /*8u!!$Hi*!/

Can't decide if that ( idiotic) comment is more "Lord Of The Rings" or "Highlander" ... either way it's entirely fictitious .

Jeppy profile image
Jeppy in reply to tattybogle

😁😁😁😩 yes. how to phrase idiotic untrue and hysterical in a professional phrase🤔

DippyDame profile image
DippyDame in reply to Jeppy

Don't apologiseJeppy....I rant ( about T3) all the time possibly to the irritation of some...

.I'm high dose T3 -only and that ignorant comment is sadly becoming more typical of the NHS approach to treating thyroid disease.

These doctors are not worthy of their stethoscopes!

Why do so many patients arrive here often in despair if all in NHS thyroid land is tickty boo!!

Maybe a silly question, but can you see another endo

Feel another rant coming on....

Jeppy profile image
Jeppy in reply to DippyDame

lol sorry !

Hate getting angry this is my prob a vent sure helps

Iv written back to him three times unsentimental them! Some don't care about people for sure

Yes I saw another who wrote he was going to trial me T3 then he retired and wrote from his new private clinic I could but it for extortionate cost

Jeppy profile image
Jeppy in reply to DippyDame

That was ' letters unsent'.

It's like he's Gowding

Only one thyroid med indeed!!!?

They should look on here

Jeppy profile image
Jeppy in reply to Jeppy

He put at top unhealthy preoccupation with health !! 😩🤷‍♀️. He listed it under hypothyroid

TaraJR profile image
TaraJR in reply to Jeppy

Does this endo not read anything to do with hypothyroidism treatment? Does he have no professional development? (I assume you're in UK)

All national guidance says T3 can be prescribed if T3 does not make you well. Whereabouts are you?

Jeppy profile image
Jeppy in reply to TaraJR

Cheshire. Uk

So what do you write back to Endo? Begs the question!!

TaraJR profile image
TaraJR in reply to Jeppy

I know it's not easy! Can you request to see someone else?

If you're on Facebook, join us on ITT Improve Thyroid Treatment group. We have a template letter to send to Endo, GP, MP, PALS, Healthwatch etc stating all the national guidance and parliamentary statements on T3. They ALL say T3 can be prescribed if T4 doesn't work.

The price of T3 is ow over 80% less than what it was at its height, so cost should not be an issue now either.

Of course,, it will depend on what your test results are. Do you have those? Do they show a low T3?

Jeppy profile image
Jeppy in reply to TaraJR

my t3

4..4. (3. 3 - 6..2)

It doesn't budge ,xxxx

I was the same 6 yrs ago on no medication and now I take 100/125 levo

Jeppy profile image
Jeppy in reply to Jeppy

is madness as his retired ex colleague was about to put me on nhs T3 trial then he opened a private clinic and offered it to me at extortionate cost

TaraJR profile image
TaraJR in reply to Jeppy

What is your T4, with this T3 level?

Jeppy profile image
Jeppy in reply to TaraJR

T4 at 19. (12-22)

Jeppy profile image
Jeppy in reply to TaraJR

endo listed me as hypothyroid plus Health Obsessional ( forgotten his exact term)

He put 'there is only one medication'

tattybogle profile image
tattybogle in reply to DippyDame

My use in this post of this particular study based on TSH is NOT to accept the use of TSH 's current dominance , or promote it... or even to accept the findings here .

It's findings are extremely limited due to TSH being the only large scale long term data they had available to them , (and the study authors admit this limitation i think ) .

However , in order to answer the (very useful) question the authors were trying to answer :

"Context: For patients on T4 replacement, the dose is guided by serum TSH concentrations, but some patients request higher doses due to adverse symptoms.

Objective: The aim of the study was to determine the safety of patients having a low but not suppressed serum TSH when receiving long-term T4 replacement."

using regional datasets between 1993 and 2001.

A population-based study of all patients in Tayside, Scotland.

All patients taking T4 replacement therapy (n = 17,684) were included."

....they had no choice but to base it on TSH, due to the limited blood test's that have been done on real NHS patients as a result of policy ... they simply did not have full data sets for fT4, let alone fT3.

To do an 'observational' study of this scale including fT4 and fT3 data you first need 17.000 patients with fT4 and fT3 and TSH results taken regularly by the NHS for 8 years . If they 'd tried to include T4/T3 in 2010, there would be no paper .

So while i don't accept TSH the most useful measurement , i DO accept the authors were working within the limitation they had at the time.

I'm pleased they asked the question.

I'm pleased they bothered to make the distinction between 'low but not supressed' and 'supressed'.

And i'm very pleased they also looked at risks for over range TSH / Sub-clinical hypo ( .... and didn't bury them) .

The purpose of my post is entirely pragmatic ... TSH is the stick they are using to beat us with ... this post is "me showing people how to take the stick off them ,and use the same stick to hit back"

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

in case anyone is in any doubt .... no , i don't think TSH is the best measurement to monitor treatment .. and no i don't think it is a reliable/ accurate measure of much at all . My own TSH results proved that to me in 2003:

TSH at diagnosis ~ 6.8

50mcg Levo for 7 weeks~ TSH 2.9

100mcg Levo for 5 months ~TSH 2.5

150mcg Levo for 3 months ~ TSH 2.7

175mcg Levo for a couple of weeks ~ TSH 0.001

TSH is a highly unreliable method of monitoring the effect of a dose of thyroid hormone relacement.

DippyDame profile image
DippyDame in reply to tattybogle

I understand your stance on TSH....we're singing from the same music sheet tattybogle

I'm ranting about what could/ should be done rather than about what has been done.

i DO accept the authors were working within the limitation they had at the time.

Yes they had limitations but research is about looking at the possibilities beyond existing limitations....we'd still be living in caves if we hadn't looked beyond what was in front of our noses.

Right now there appears to be no indication that the NHS powers-that-be can see beyond the end of their noses....or wish to.

The purpose of my post is entirely pragmatic ... TSH is the stick they are using to beat us with ... this post is "me showing people how to take the stick off them ,and use the same stick to hit back"

To hit back a bigger, or different", stick" may be required, not the same stick.....

I'm probably suffering from a bout of " Mary, Mary ((not my name!) quite contrary" because I can see very little chance that the attitudes and opinions of the decision makers will deviate from just that...to facts!

And meanwhile patients continue to suffer.....this determined focus on TSH is tantamount to medical neglect.

I wish someone had the clout to change this debacle.

TSH110 profile image
TSH110 in reply to DippyDame

we need a telegraph pole of a stick!

klr31 profile image
klr31

Whenever I change dose my TSH hardly moves, only my T4 and T3. Karen

Jeppy profile image
Jeppy in reply to klr31

why is this pls? Do you know? For me very similar, my t4 always been near the top and t3 near the bottom I want to know why I take more t4 when my own supply was good?

klr31 profile image
klr31 in reply to Jeppy

I don't really but assume the TSH isn't very sensitive to changes in dose. I was taking T3 at one time which I know can knock TSH down and keep it low.

Do you know if you're absorbing it OK? Are your vitamin levels OK?

Karen

Jeppy profile image
Jeppy in reply to klr31

yes thnx. I'm keen on vits it really helped some

But absorption must be a prob as conversion poor

Frustrating all you want is to feel alive

Hrt helps a bit then TSH shot ip to 7

klr31 profile image
klr31 in reply to Jeppy

Hope you're taking HRT at a different time to thyroxine.

tattybogle profile image
tattybogle in reply to klr31

HRT has it's effect on thyroid hormone levels regardless of when it's taken ( which isn't to say it;s fine to take them together , just saying that separating them 'in the stomach/gut doesn't prevent the main effect )

it is dependant on what sort of HRT and how much of what is in it ,,, but it goes something like this:

....estrogen increases the amount of TBG (Thyroid Binding Globulin) produced via the liver , This is the stuff that 'binds' T4 ( not sure about T3, but probably that too) when carried round in the blood . the T4 that is not 'bound' by Thyroid Binding Globulins is what we call "Free T4" (fT4)

The combination of Free T4 AND the T4 that is bound by TBG ,is what we call "Total T4" (TT4)

An increase in estrogen level therefore means more of our T4 is 'bound' and this is ( i think ?) why a dose increase of thyroid hormone is sometimes needed following the introduction of ( some types of ) HRT... (because fT4 is lower and therefore TSH goes up ? )

and why after stopping HRT, that dose may become a bit too much ... ( ? and why some of us find we need a bit lower dose of levo following menopause (if not taking HRT)

Taking HRT 'away' from oral thyroid hormone doesn't prevent this increase in TBG , which s related to increase in estrogen level and it's effects in the liver , rather than reduce absorption of thyroid hormone from the gut.

This explanation should be read with caution , a it's based only on vague memory from trying to get my head round it a couple of years ago .

Jeppy

Jeppy profile image
Jeppy in reply to tattybogle

thanks for explaining about binding

Wondering if it's same with patch through skin🤔 But still, mine went upto 7 and taking the lowest conti patch for older. At least I felt alive. Iv stopped hrt as having op but will resume how can I not I need to protect bones

tattybogle profile image
tattybogle in reply to Jeppy

Don't know it's expected to have such a big effect with the more modern HRT's and patches etc ... most of the research showing HRT mean levo dose needed increasing was probably relating to the older forms of HRT that ?i think, had significantly higher amounts of estrogen than modern varieties do .

But if TSH /fT4 /fT3 results show your dose needs increasing/ or decreasing , then it needs increasing/ decreasing .. regardless of what the science says 'should' happen with HRT.

Some of us have bodies that haven't read the books.

Jeppy profile image
Jeppy in reply to tattybogle

well said. It was the tablet form through liver that caused concerns

But it's a bit of a shock when lowest hrt patch puts TSH up to 7 from 4

Jeppy profile image
Jeppy in reply to klr31

it's a patch not tablet as it goes through liver

jimh111 profile image
jimh111

The study group was people on levothyroxine. Some of these will have a low TSH because their pituitary isn’t performing well. For these people a low TSH isn’t likely to be associated with risks. Assuming this is a small number it wouldn’t have much effect on the risk of a low TSH in those with a healthy pituitary.

TSH110 profile image
TSH110

My heart pains go away completely with a TSH of 0.05 so it must vary from person to person what is too suppressed and what isn’t. But good that it explodes the myth that any suppression is instant heart attack etc territory. That’s on NDT btw.

Jeppy profile image
Jeppy in reply to TSH110

why does heart get pain?

Lack of t3?

TSH110 profile image
TSH110 in reply to Jeppy

T3 plays an important role in regulating heart beat I’m not sure of the exact mechanism involved I presume it’s electrical impulses not quite in synch causing the heart muscle to malfunction but that might be to simplistic or even wrong, it seems to affect the function of specific chambers of the heart…. but if you get too much or too little it causes heart problems like chest pains angina and even heart attack. Cardiologists sometimes diagnose thyroid problems. If I can find more info I will post it for you.

Found some…..this paper is quite informative:

ncbi.nlm.nih.gov/pmc/articl...

and this one:

journals.physiology.org/doi...

obviously, it’s quite complicated.

Jeppy profile image
Jeppy in reply to TSH110

thank you. I'm very interested but I find generally I am not proactive in diagnosing and treating myself as yes it's all so complicated. Maybe the amount I have is enough for my needs but why I take t4 when I had a good level I have never understood and the question goes unanswered

DippyDame profile image
DippyDame

I'm going to copy my response in an earlier post re TSH ....hope you don't mind.

Maybe it's just me but the current fixation on TSH concerns me greatly and I might question...

AS LONG AS YOUR TSH is 0.04 or ABOVE .

In that case I guess I should be planning my " departure".

"Horses for courses"!

Copy...

It strikes me that by focussing on TSH they are putting the cart before the horse!!

TSH tells it's story... but that is created by the reflection of the levels of FT4 and FT3

They are the important markers....particularly FT3.

As the active thyroid hormone much can be extrapolated from it's level....along with that of FT4

Conclusions: Patients with a high or suppressed TSH had an increased risk of cardiovascular disease, dysrhythmias, and fractures, but patients with a low but unsuppressed TSH did not. It may be safe for patients treated with T4 to have a low but not suppressed serum TSH concentration.

Turn that around and high or suppressed TSH is the reflection of low or high hormone levels

Why not just test the individual hormones and cut out the 'guessing game" as to which hormones in the serum are causing either the high or suppressed TSH?

Surely the symptoms arise from the thyroid hormone level....not from the TSH per se which is invariably an unreliable marker.

If TSH were a reliable marker ( beyond it's original function of identifying hypothyroidism) then why do so many patients who are medicated by TSH continue to struggle?

They are not being medicated with the correct hormone dose....the individual hormones are sidelined in favour of TSH which only reflects combined FT4 and FT3 levels!

Granted, we are all different but surely using individual Free levels alongside clinical evaluation is more accurate that a ( possibly) fluctuating TSH level.

The powers that be appear to need to see a neat set of results which fit into their neat, sets of categories. Or if you like some of us are "square pegs" that can't be fitted into neat round holes. When the square peg brigade arrive the medics struggle!

As a square peg I've been there.....but I'm only an ill fitting square peg because nobody has had the nous to understand that I need a square hole, not a round hole.

We keep trotting out the mantra that, " we are all different" which is true........but how much effort has gone into ensuring that the low, square cohort, have a place to go and to recover.

Surely their symptoms are the result of wrong medication which attempts to fit then into that damned round hole ....when, in fact, they are square!

And, not the result of an unreliable TSH reading on a screen.

In days if yore they used their heads....

Change required....because the horse is falling over the cart that it's been forced to follow!!

Rant over!!

arTistapple profile image
arTistapple in reply to DippyDame

”that the low square cohort, have a place to go and recover.”

Just hits the spot as far as I am concerned. A truly articulate point. If only someone who could actually bring about this level of ‘change’ was listening.

Singwell profile image
Singwell

Interesting. My bone density also took a nose dive for no apparent reason. Now I know why. Question please - what's the difference between Low TSH and Suppressed TSH? I can see the figures are different, but what's the significance of the labelling? Is it to do with different medication approaches?

Jeppy profile image
Jeppy in reply to Singwell

I can go with TSH not being really relevant if it's suppressed, as to why is it to mimic the numbers of that of a healthy person 🤔 makes no sense really, it's what makes you feel wellness that's viral surely, regardless

Singwell profile image
Singwell in reply to Jeppy

That's how I'm going forward, yes. I just wondered what it meant in a clinical context.

Greybeard profile image
Greybeard in reply to Singwell

Clinicians usually consider less than 0.1 to be the threshold for tsh being suppressed.

tattybogle profile image
tattybogle in reply to Greybeard

I've heard/ and read all sorts from endo's , research authors , and GP's... some of them are careful to define exactly what they mean ... and some (idiots) use 'anything below range' interchangeably with 'supressed' .

There needs to be proper accepted definition of the terms used in endocrinology / research for supressed / low etc ,.... as surely this is a prerequisite for any intelligent research/ conversation about 'risk' with patients .... but as usual with the endocrinology profession.. they haven't actually bothered to sort this out yet cos "it's only the thyroid , so we 're not very interested ".

Jeppy profile image
Jeppy in reply to tattybogle

they aren't trained in it my last gp I miss a lot. He was happy to say this and that I'm more informed even and what might he do to help !

It's far too complex for them to fiddle with and shame on endos like this one I seem to-be under

They seemingly move you around when you don't respond to levo

tattybogle profile image
tattybogle in reply to Singwell

There is NO FIXED DEFINITION of the cut off point between 'supressed' vs 'low but not supressed' vs 'low' for TSH .

Different authors / studies will simply use whatever terms as they please.

The only way to know what is meant in a particular instance is to look at the technical details of a study you are reading, and see what levels they use for each group .. (many studies make no distinction at all and just use "low" or "supressed" for anything below TSH ref range.

In this study they simply chose to use a figure of 0.04 to draw the line between 'low' and 'low but not supressed' .. they could have used 0.02 , or 0.06 or anything they felt like.

Some people use "TOTALLY Supressed" to mean "So low it was unmeasurable by the test used " this is when you see a TSH result that starts with a " < " .

eg. on my NHS results , if i get <0.05 [ 0. 57-3.6] it means that test platform can't accurately measure a result less than 0.05 .. so my result could be 0.0499, or it could be 0 .000 or anything in between.

some test platforms can measure lower than others , so you may see < 0.01 or <0.005

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

unfortunately what can happen in real life is eg a GP reads a study like this one ...that says "Conclusions: Patients with a high or suppressed TSH had an increased risk of cardiovascular disease, dysrhythmias, and fractures," and takes it out of context, and interprets 'supressed' by their own definition of what 'supressed' means to them eg. 'anything below ref range' (rather than what the study authors actualy meant).. so it becomes like 'chinese whispers' ... and before you know it, people are using this study to prove "low TSH is risky for heart and bones" .

... which is exactly what HAS happened. This study IS used by the writers of NICE guidelines to back up their concern about "low TSH/ risks " ( well strictly speaking~ they don't refer directly to this study , they quote another study .. but when you look up that one , it has no evidence 'of it's own' to back up the claim , it refers to another one ,... which also has no evidence of it's own ... it refers back to this one ... chinese whispers)

Jeppy profile image
Jeppy in reply to Singwell

may be a good question on Newpost

fiftyone profile image
fiftyone

Should any research be taken as 'gospel'? Maybe there are even more discoveries to be made about connection between T4, T3,TSH

Singwell profile image
Singwell in reply to fiftyone

I think tatty meant as additional armoury when dealing with our medics. I'm certainly going to use it if needed.

tattybogle profile image
tattybogle in reply to Singwell

Yes absolutely Singwell ... that is my reason for finding this study useful, and the only real purpose of this post.

perhaps i should retitle the post " A Tool (for use on GP/Endo ) "

tattybogle profile image
tattybogle in reply to fiftyone

should any research be taken as gospel .. nope .

and i don't .

But N.I.C.E do.

... and while they do ,and use it to set the guidelines for the GP's who treat us.. sometimes its n.i.c.e. to use their own 'evidence' against them .. to "hoist them by their own petard"

Singwell profile image
Singwell in reply to tattybogle

And thanks for the other reply too. Makes sense. Unfortunately modern medicine guidelines re best practice have become stats driven as opposed to practitioner wisdom of experience driven.

JAmanda profile image
JAmanda

Thanks for that. I think they’ve been saying that for a while now -trouble is for me and many others I think, that taking t3 suppresses tsh further than that - mine is 0.005 on 25 t3 and now 0.01 on 20 t3. My Doc isn’t unduly worried but I do wonder if I should be!

Jeppy profile image
Jeppy in reply to JAmanda

hi are you taking levo too? 🤔

Read so much in this minefield , so much variation yes

Do we need to take t4 along with T3 ? Read this too somewhere & what works for one not another if it's all about the numbers

Back in the day when ndt was given it was T1 T2 T3 and T4 that you got 🤔 You read that everyone got wellness back ( or did they?)

😊

JAmanda profile image
JAmanda in reply to Jeppy

yup I take 100 Levo too. Honestly no idea what everyone else takes nor if I actually need the t3. For me getting vitamins high is the most beneficial… but I’m too scared to stop the t3!

Jeppy profile image
Jeppy in reply to JAmanda

hi. Absolutely understand all that

Vits have helped me the most id love to stop levo 🤷‍♀️ my numbers are the same on 125 so more than confused plus if I stop do I still produce as I did before ?

Hows hip

Jeppy profile image
Jeppy in reply to JAmanda

...what are you most scared of

JAmanda profile image
JAmanda in reply to Jeppy

oh no I’d never stop the thyroid meds! I’d keep the Levo. Hips really ok. Feet not sheer agony. But it’s all guesswork as to why.

Jeppy profile image
Jeppy in reply to JAmanda

burning feet I used to have read it shop symptom Yes it's a Mai wand no real perfect solution sadly but we get to a better place 👍🏼. Stress doesn't help

Jeppy profile image
Jeppy in reply to JAmanda

sorry typos

Feet are can-be hypo mine improved over time but we're really uncomfortable before ( I had 3 pairs of shoes in a bag for daughters wedding !)

The why and where fores!

Iv just spoken at Louise Newtons I'm having a video consult I need some positivity badly and control back

tattybogle profile image
tattybogle in reply to JAmanda

we cannot apply the results of this observational study to people taking any T3.

The study was done (in 2010) of patients taking (as far as they knew) 'Levothyroxine only' between 1993 and 2001 to asses their long term risks as result of taking levo with TSH at various levels .

Patient's taking T3 in any form would undoubtedly have had different TSH levels to these.

and therefore this paper cannot be used as 'evidence' when discussing dose of Levo + T3 or NDT , or T3 alone .

wellness1 profile image
wellness1 in reply to tattybogle

Thanks for making a separate post about this study.

this paper cannot be used as 'evidence' when discussing dose of Levo + T3 or NDT , or T3 alone.

I take your point. Really, I do.

But I wonder whether this study might have any use as a tool for discussion with prescribers, even for those on combination therapy, NDT, or T3 only. People might take different routes to arrive at their TSH result, but perhaps a prescriber would consider that if a large group on T4 monotherapy suffered no adverse outcomes with low but not suppressed TSH (FT4/FT3 unknown), it might be reasonable to allow for the possibility that those with similar TSH results (and Frees in the reference interval) on different treatment might fare similarly? Perhaps the more rigidly focused on TSH as the essential marker, the more susceptible they'd be?

I understand that a study that includes participants' TSH, FT4, and FT3 on different therapies wrt to these outcomes is what's needed. I'm not holding my breath for that. In the meantime, in treatment discussions that focus on low TSH and concerns about heart/bones, is it completely inappropriate to refer to this study, not as 'bombproof evidence', but as information with potential relevance? If someone has '0.04 or over' but has got there by including a bit of T3 (or another treatment) they won't find the relevant comparable study they can trot out, perhaps ever.

Sorry tatty :) These are some rhetorical questions I'm not expecting you to answer, just think it could be part of a discussion of this paper's significance.

tattybogle profile image
tattybogle in reply to wellness1

I used 'bombproof ' in the context only that this study cannot be discounted by any GP or Endo as "not good enough quality evidence" or "not relevant" to counter the current N.I.C.E guidelines .. because it was used to FORM the NICE guidelines.

if people try to use this study as 'evidence'(tool) to support a discussion of "low TSH on T3" with a endo who doesn't really want to prescribe T3 anyway or know much about it , ( and several members have tried this ).. then any GP/ Endo who can be bothered to read the first few lines will rapidly dismiss their argument , saying "oh ho .. you have misunderstood it ( my dear) ......this is just for patients taking levo ...you are taking T3 therefore you're still gonna die from low TSH" ( some T3 patients who did manage to get their GP/Endo to read it got this response )

radd profile image
radd

tattybogle,

I remember this paper as it was broad cast as a ‘Media Release’ at a Society for Endocrinology meeting in Manchester. I actually printed the article off. Sadly this was in 2010 and not much has happened since as GP’s remain beholden to unchanged guidelines. 

Well done for locating though tats. There is always a small chance of a more open minded GP taking some notice.

tattybogle profile image
tattybogle in reply to radd

i used it with success a few yrs ago to get my GP to ( reluctantly) allow my Levo dosing which had consistently given TSH of (very conveniently) 0.05

Id tried a lower dose first , with very bad effects. So i needed to argue against the " but you'll die " ( actual quote )

Jphill49 profile image
Jphill49

thank you, that’s very useful information.

Litatamon profile image
Litatamon

Thank you tattybogle. Useful information & great discussion.

mountainice profile image
mountainice

I am on T3 as well as T4 and my TSH has been <0.01 ever since I started on T3 in May 21. I feel ok, apart from my sleeping has gone horrendous since Christmas. Do I need to worry about that suppressed TSH ?

tattybogle profile image
tattybogle in reply to mountainice

Do you need to worry about it ?.....

is keeping your TSH a little bit higher and still feeling ok a realistic option for you ?

if it is, then do it .

but if it's not possible for you to have higher TSH without feeling pants ,why worry about something you can't do anything about ?

if sleep is becoming a problem then trying a very slightly lower dose might be a good idea anyway.... my sleep gets bad if i'm a bit overdosed.

But a the end of the day it's a question of our attitude to Risk vs Quality of life .. and that's a question we have to answer for ourselves ,

There are some useful discussions about Risk vs Qaulity of life on these posts:

healthunlocked.com/thyroidu... tsh-and-bone-density?

healthunlocked.com/thyroidu... low-tsh-not-related-to-bone-density-loss-new-paper

healthunlocked.com/thyroidu... suppressed-tsh-dangerous-wheres-the-evidence?

healthunlocked.com/thyroidu... tsh-and-the-more-mature

healthunlocked.com/thyroidu... risks-of-suppressed-tsh-analysis?

healthunlocked.com/thyroidu... dangers-of-suppressed-tsh?

healthunlocked.com/thyroidu.... suppressed-low-tsh-osteoporosis-and-atrial-fibrillation-evidence.

healthunlocked.com/thyroidu... armor-thyroid-and-bone-damage

TaraJR profile image
TaraJR in reply to tattybogle

I asked 3 well known endocrinologists on webinars/zooms/twitter whether it's a low/suppressed TSH in itself that can cause problems eg osteoporosis or AFib, or the high/over range T4 or T3 themselves. They all said it wasn't really the TSH itself. I'll copy here what I wrote from the conversations:

Q. "Do problems arise from suppressed TSH or High T4/T3?"

Prof Simon Pearce 2022: "An interesting question and a subject of debate. It's the T4/T3 really, as bones are sensitive to thyroid hormone levels, rather than a suppressed TSH. But a US study showed a fully suppressed TSH can lead to some osteoporosis in mice. You should generally avoid both."

Prof Colin Dayan 2021: "T3 often suppresses TSH. You can take enough T3 which doesn't suppress TSH. But if that's the only way to feel well, you may want to do that, though it's not ideal. It’s a trad- off … low quality of life versus taking a risk. It is a low risk. At the end of the day, it's only T4 and T3 that matter. TSH doesn't matter as it's not acting on tissues. But we use TSH to judge on average what is happening in tissues. It's the levels in the cells that matter."

Prof Antonio Bianco: "The problem in every case is an excess T4 and/or T3. The low TSH levels only reflect the excess of thyroid hormones. TSH has no effects on the heart. Sometimes, the excess of thyroid hormones is so small that the only indication is a low/suppressed serum level."

mountainice profile image
mountainice in reply to tattybogle

thank you, I will read those when I sit down later .

It's just the studies usually talk about when on T4 only, not mentioning if on T3 as well. I have just looked at TaraJR post and this following statement:

Prof Antonio Bianco: "The problem in every case is an excess T4 and/or T3. The low TSH levels only reflect the excess of thyroid hormones. TSH has no effects on the heart. Sometimes, the excess of thyroid hormones is so small that the only indication is a low/suppressed serum level."

=====================================

How do we then know the excess of hormones that any one person may have (either small or large ) from this statement.

'Sometimes, the excess of thyroid hormones is so small that the only indication is a low/suppressed serum level.'

tattybogle profile image
tattybogle in reply to mountainice

~ a large excess of thyroid hormones would be expected to cause some symptoms of overmedication. which you would expect to improve if the dose was lowered

~ a small excess of thyroid hormones that causes absolutely no symptoms of overmedication is..... erm ... only a very small worry.

We can't prove there is 'no problem at all' , until there is enough long term data from patients using T3 and having a low /supressed TSH.

But by the same token , 'they' can't prove there IS a problem .

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