Please can one of you lovelies guide me on understanding my T4:T3 ratio?
Below are test results from NHS in January and Medichecks in February 2023 and below that waffle about pharmacist at GP surgery reviewing my results/ medications who is freaked out by TSH & that I take 30mcg amitriptyline. Made me feel about 85 (I'm 59)
Medichecks 15/01/23 (these are very similar to results in August 2022)
I am on 125mg levothyroxine and endocrinologist gave permission for below range TSH so long as it was detectable with FT3 and FT4 in range
I also take 30mcg amitriptyline for pain at bedtime
I have had pharmacist at GP surgery review my recent blood results ( GP was looking for autoimmunity markers to do with pigmentation on arms, lichen sclerosis and 'wobbly' cortisol levels (SST in October was deemed 'no further' action but don't have the actual numbers & I feel better than I did in the summer when saliva cortisol test was worryingly low )
The pharmacist is freaking out about my low TSH and wants me to reduce my dose(told was not prepared to and would source from abroad although I have no idea how to) as I 'will have problems with bone density' Have redirected her to endo's TSH permission letter and refused to even consider it. I have agreed to a DEXA scan
She also says it will cause heart problems, I know I've seen something here about the whole thyroid picture needs to be considered and low T3 linked to heart problems but can't find it. After I explained I had a full heart check at A&E in October which was concluded to be due to stress induced reflux after unexpected sudden death of my mother, she still insisted I needed another ECG. I have since had another close relative die that I am organising the funeral for, so lots of extra stress just at the moment, but I'm taking life one minute at a time.
She has also declared I am a 'falls risk' because of the amitriptyline and my age (59) and wants me to reduce /stop taking it and to have a DEXA scan. I have agreed the DEXA as I know I have not had enough energy to walk 10000 steps daily for 7 years without brain fog setting in after a couple of days so for that reason alone I would think it a useful investigation. My online notes say I have WHO FRAX 10 year hip fracture score of 0.4% and WHO FRAX 10 year osteoporotic score of 4.5% neither I or my parents have ever broken a bone.
Any thoughts on how I can educate the GP surgery / substantiate staying on current levothyroxine dose or should I consider reducing the dose a little? I want quality of life over a longer life where I can't do anything.
Thank you for persevering through to the end of this essay. xx
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StillEverHopeful
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Please can one of you lovelies guide me on understanding my T4:T3 ratio?
The FT4:FT3 ratio is a guide to how well you convert T4 to T3, that's all. It's said that a ratio of 4:1 and below is good conversion, over that is poor conversion. But that's not the full picture. It's better to look at the FT4 and FT3 levels (in my opinion). You have, with your 3.1.23 results
Free T4 (fT4) 15.8 pmol/L (9 - 19.1) 67.3%
Free T3 (fT3) 4.7 pmol/L (2.4 - 6.0) 63.9%
As you can see yours were very well balanced so your T4 to T3 conversion was showing as excellent.
Your results from 15.1.23 are somewhat different at
Free T4 (fT4) 19.8 pmol/L (12 - 22) 78.0%
Free T3 (fT3) 4.9 pmol/L (3.1 - 6.8) 48.6%
and show that your conversion is not so good.
So we have to ask, were both tests done under the exact same circumstances, with last dose of Levo 24 hours before test and no biotin/B Complex or any supplement containing biotin left off for 3-7 days before test.
What can affect thyroid results is acute illness. Your 3.1.23 results could be questionable because you tested positive the next day and had a flu bug the week before. We should wait a few weeks after recovering from an acute illness before testing so the fact that your 15.1.23 test was so soon after your Covid means those results could also be unreliable.
Was CRP tested when these tests were carried out? This is an inflammation marker and is usually raised when infection is present. If your CRP was raised then your ferritin result will be unreliable because ferritin rises with inflammation/infection.
I am on 125mg levothyroxine and endocrinologist gave permission for below range TSH so long as it was detectable with FT3 and FT4 in range
In that case your Pharmacist should butt out, Endo trumps Pharmacist, the Pharmacist is not the thyroid expert so they should leave it to your Endo and shouldn't get involved. They can always phone to Endo to discuss if they have any concerns.
She also says it will cause heart problems, I know I've seen something here about the whole thyroid picture needs to be considered and low T3 linked to heart problems but can't find it.
This is where most doctors/medical practioners are ignorant. They think a low/suppressed TSH is going to cause osteoporosis, atrial fibrilation, etc. This has been debunked - see 7 myths of hypothyroidism on ThyroidUK's website and scroll down to
The myth that a suppressed TSH leads to Osteoporosis
Also, Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine (the professional publication for doctors):
"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l. In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l. Most patients will feel well in that circumstance. But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l. This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l).*"
*He confirmed, during a talk he gave to The Thyroid Trust, that this applies to Free T3 as well as Total T3 and this is when on Levo only. You can hear this at 1 hour 19 mins to 1 hour 21 minutes in this video of that talk youtu.be/HYhYAVyKzhw
He's unlikely to say that if there is evidence it will cause osteoporisis (or AF).
“I am on 125mg levothyroxine and endocrinologist …”
It wasn't me who wrote that, that was a direct copy/paste quote from StillEverHopeful's post. I certainly know the difference, but many members put mg instead of mcg and whether that's a typo or just a genuine mistake I don't know.
You are an angel! Thank you so much for giving me all the evidence in one place
as you realised mg was a typo and should be mcg
For January I had been off all supplements from Christmas, blood taken at 9.30am, might have had a cuppa before as I didn't know they were doing thyroid but left levo until after. Remarkably I only tested positive for 2 or 3 days and felt much better than when I had the fluy thing. No CRP test
February blood taken at 7.30am only water to drink, levo after, had been off B vitamins for 5 days. CRP < 0.3 (0-5) Have just remembered I started 10mcg estradiol pessaries daily for 2 weeks then 2x week after January blood draw, but I keep forgetting them on 2x week and saw the PIL said something about caution with thyroid problems. I was also possibly was more diligent to be well hydrated for this test.... I may be drinking more coffee since mid January, life has extra unavoidable stress with sudden death of parent in the autumn and then supporting another elderly relative who died end of January, now managing the funeral etc.
I am aware I'm not eating as well as I have done. When I ordered this test it was on special and I was particularly interested in D level and if Ferritin had dropped once bug free. I find the different ranges for Ferritin curious and the ratio shows the drop is not as big as I initially thought.... the thyroid calculator is brilliant in converting to percentage.
I was very firm with the pharmacist that I would not reduce levo and got stroppy enough to say I would source from abroad if it was reduced, eventually she said to make an appointment to see a doctor, she couldn't make the appointment ..... nigh on impossible at our surgery have to phone at 8am to see if they will give you a telephone appointment and if there are none left you have to repeat each day until they can give you a phone call, I don't want to hang on the phone for an hour to be told phone back tomorrow so haven't even tried to get a phone appointment.
I'll arrange another medicheck thyroid test in 6-8 weeks
I certainly feel equipped to 'do battle' if needs be, Thank you so very much for all the help and links. xx
Hi SilverEverHopeful I just have a silly question .... why has the ft3 range changed? In January your ft3 was 4.9 with the range for ft3 at: (3.1 - 6.8) 48%
BUT in February T3 (fT3) 4.7 but with a different range (2.4 - 6.0) 63.9%
different labs use different platforms (test machines) made by different manufacturers.. different platforms use slightly different testing methods, this leads to them having different numbers for their (95% population) 'reference range' .
these 'factory settings' are then adjusted very slightly once they are purchase by a lab to fit closely with local population 95% ref range samples . (These local population samples are also updated occasionally so the range may be very slightly tweaked again)
The 'number' you get for the result also changes with different ref range ... but the result should still be roughly the same % through range ..
eg a blood sample that had a high amount of FT4 when compare to the rest of the population would get :
22 [ 12-22] from a lab that had a [12-22] range..
but the same blood sample would get a result of :
14 [7-14] from a lab that used a [7-14] range .
Both are 100% of the way through the reference range .
they were different labs one taken at 9:30 am the other at 7:30am
On reflection although total dose remained the same the dose of tablets did change as they couldn’t source Eltroxin of regular dose for a couple of months other wise not really sure why the percentage through range changed…. Perhaps stress played a factor. I am travelling through the unavoidable stress with the death of a close relative and all the organising that entails.
This paper is part of the basis for the current NHS thyroid treatment guidelines , it was used as evidence to back up their concern about "low TSH /overtreatment with levo/ risk to bones and heart" ( so they can't say it is 'not good enough evidence' if 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 ...
you can use this paper as a very strong argument as long as your TSH is 0.04 or above . It was a very large, long term study of 17,000 real patient 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 one deals with the alleged risk to bones.. it is a recent study of patients whose TSH was kept deliberately supressed with levo, long term ( to prevent recurrance of thyroid cancer) if found no significant increase in bone loss .
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)
Be very wary about being pressurised into a Dexa bone scan unless YOU want one ( personally i'd reconsider your agreement ) ...... if they find any issues (even if they are issues that are commonly expected for people your age group who are not on Levo ) then the results could potentially be used to over ride you endo's letter of permisson ( which is currently your 'Get Out Of Jail Free' card.)
Lots to think about as I am close to suppressed TSH. I hadn’t considered that a Dexa scan could trump the get out of jail card from Endo. I am curious to know what my bone density is, I had a hand X-ray about 4 years ago & was asked if I’d ever had a DEXA but only later wondered if the X-ray showed bone loss
Your reply to motherbear has also given me food for thought, may play with reducing a tiny amount to keep the t4 to T3 at a better level.
I now just need enough time to read all the links thoroughly.
A really big thank you for all the information. xxxx
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