Get to know about Hypothyroidism

[abhi747]

I am seeing a 27-year-old woman for a potential life partner. She is 5'3" tall and weighs 55kg. She has subclinical hypothyroidism as per her doctor and takes 25mcg of Thyroxine daily.
History:
* Diagnosed with subclinical hypothyroidism a couple of years ago after some weight gain and hair loss.
* Initial TSH was 8mIU/L when diagnosed.
* Doctor prescribed 25mcg Thyroxine.
* Current TSH is around 2.5mIU/L roughly with the medication.
* Family history of hypothyroidism (mother and grandmother).
Questions:
1. How serious are subclinical hypothyroidism and overt hypothyroidism? What are the common symptoms and implications?
2. Is it curable or lifelong medication needed?
3. Any pregnancy complications or risks of passing to a child?
4. Is TSH of 8mIU/L diagnostic of subclinical or overt hypothyroidism? I came across a few articles online stating that subclinical hypothyroidism is when TSH is high but has no symptoms and TSH above 5 is overt hypothyroidism.
5. How many chances are there for subclinical hypothyroidism to turn into overt hypothyroidism?
6. Can she live a healthy life with medication and monitoring without any symptoms and implications?
7. Any dietary restrictions or other special care needed besides medication?

I would appreciate any advice from doctors or others knowledgeable about managing subclinical hypothyroidism. Please advise if this condition is something to be concerned about for her health or our future children. Thank you!

[gimel]

Regarding reference ranges, the range for TSH is fairly consistent at all locations.  For FT4 and fT3 it is a different story.   Depending on the standards used to calibrate the lab's specific test equipment, results and ranges calculated from the database of those results can vary from one lab to another.   That is why it is a good idea to always compare results to the reference ranges from the same lab.  

Yes, you should ask her about what symptoms she had at the time of that first test, for TSH.   Also, it is quite easy to overlook some symptoms of hypothyroidism, so if she is agreeable also ask her to review the list above and identify any that she has.  I also suggest that you get her tested for Free T4 and Free T3, along with Vitamin D, B12 and ferritin.  Always insist on testing the Frees.  Total T4 and Total T3 are not nearly as useful.   Also, at this point further tests for TSH are a waste of time and money. Any changes in her med dosage should be based on symptoms and also FT4 and FT3 levels.  

Yes, the implication for hypothyroidism is lifelong medicine and I would say it is less difficult to maintain adequate levels than with diabetes.  In considering marriage and having children it is very important for the fetus, that the mother has adequate levels of thyroid.  It is somewhat strange to me that she has FT4 and FT3 that are just under mid-range, while only taking 25 mcg of Thyroxine.   Because of this I am a bit suspicious that the original diagnosis may have been incorrect.  We'll know more when you are able to get the 5 tests done, and she reviews the list of typical symptoms and tells us which ones, if any, she has.  

[abhi747]

I have messaged her to confirm regarding symptoms, but there is no reply yet. She earlier mentioned she experienced some weight gain and hair fall at the time of diagnosis. Also, she used to feel lazy at times.

Can you please elaborate on "It is somewhat strange to me that she has FT4 and FT3 that are just under mid-range, while only taking 25 mcg of Thyroxine". What possible implications could be there due to this?

[abhi747]

Received her response as below -

More sensitivity to cold: Depends..I require AC frequently during summers..during winters if its cold, then sometimes dont need fan also.
Constipation (needs to use laxative or fiber): No
Dry skin (needs to use skin creme): Dry in winter I think..not throughout the year
Weight gain  (difficulty losing weight): Highest weight at the time of diagnosis was 60 kg, now 54-55.
Puffy face: If weight is gained by any person, face also changes in proportion to weight gain.
Hoarse voice: Never
Coarse hair and skin: What is this exactly?
Muscle weakness: Never
Muscle aches, tenderness and stiffness: Never
Menstrual cycles that are heavier than usual or irregular: Always normal and regular
Thinning hair: What is this exactly?
Slowed heart rate, also called bradycardia: Never
Depression: Never
Memory problems: Never

[gimel]

Hypothyroidism will usually cause multiple symptoms.  There is no evidence of that here.  So i suggest that for now the best thing for her to do is to get new tests for Free T4, Free T3, TSH, Vitamin D, B12 and ferritin and see how those look.  Based on lack of symptoms, I suspect there is no need for her to be taking the 25 mcg of T4 at present.  You will know more after the new tests are done.  With her family history of hypothyroidism, it wil be a good idea to monitor for any new symptoms, and also to regularly test as mentioned above.  

[abhi747]

Okay, I understand that the mentioned tests will show a more clear picture of the condition. But isn't it natural that with the ongoing medication, the symptoms will disappear? Or do you mean, that even with the medication, some symptoms will persist in subclinical/ overt hypothyroidism?

[gimel]

Symptoms will only disappear when both FT4 and FT3 levels are adequate.  Sometimes when those are adequate,, TSH is suppressed below range.  That does not mean hyperthyroidism, unless hyperthyroid  symptoms start to show.   Many doctors don't understand this and if TSH becomes suppressed, they will try to reduce med dosage, but that is the wrong thing to do, if there are no hyperthyroid symptoms.  And don't forget the importance of Vitamin D, B12 and ferritin.  Can you get those  new tests done for her?

[gimel]

Personally I think that Type 2 diabetes is much more of a concern than having hypothyroidism., as long as you can locate a good thyroid doctor that will diagnose and treat based on symptoms, as well as Free T3 and Free T4 levels.   But it is important to know that good thyroid doctors that will treat clinically, as described, are hard to find.  

You should always distinguish between T3, T4 and Free T3/ Free T4.  The former are interpreted as Total T3 and T4, which represent the total amount in serum.  Most of that is bound to protein, leaving only a small portion unbound.  Those small amounts  are called  Free T3 and Free T4.  Those are what you want to know.  Free T4 is a prohormone, available for conversion to Free T3.  Free T3 is the biologically active thyroid hormone that regulates metabolic activity throughout the body.  

The ATA AACE Guidelines for Hypothyroidism assume that hypothyroidism is "subnormal FT4 levels", and that TSH is  the best predictor of a person's thyroid status.  This is very wrong.  An earlier and more effective definition is " inadequate T3 genomic effect in tissue throughout the body due to  inadequate supply or, or response to, thyroid hormone".    Also, as I previously mentioned TSH has only a weak correlation with either FT3 or FT4, and a negligible correlation with symptoms typical of hypothyroidism.   So how is it that TSH is supposed to always show a patient's thyroid status.?  Diagnosis should be based on a full medical exam, an evaluation for symptoms typical of hypothyroidism, and tests for Free T3 and Free T4.  Treatment should be thyroid med,  as needed to relieve hypo symptoms, by adjusting FT3 and FT4 levels.   It is also important to test and supplement as needed to get Vitamin D above 50 ng/ml, , B12  into the upper part of its range, and ferritin to at least 100.

Taking 25 mcg of Thyroxine daily is doing nothing for your lady.  The med causes TSH to go down, which then reduces stimulation of the thyroid gland, and reduces output of natural thyroid hormone.  The net effect of taking thyroid med is basically very little until the dosage is adequate to actually start to raise your FT3 and FT4 levels.  Then the dose should be further adjusted to relieve symptoms, as described above.  

I noticed you are located in India.  That will make it even more difficult to find a good thyroid doctor that is willing to treat clinically (for symptoms),  and also willing to  prescribe  T3 mediation, if needed.  For some time I have tried to collect names of good thyroid doctors.  I am sure there must be more, but I have previously heard of only one in India, in Bangalore.  

[abhi747]

Thanks, we are located in Mumbai city of India. I will try to get her FT3 and FT4 values when she was diagnosed and her current FT3, FT4, and TSH values as per her last report. Probably this will help to figure out the condition I believe. Kindly let me know if anything else is needed.

[abhi747]

I have got her reports available so far. Let me know if we can deduce how the condition is based on it and the implications if any.

First, only TSH was checked in 2021.
When it was found around 8, Thyroxine medication was started.
Then after a few months in 2021, FT3 and FT4 were checked.

December 2021 readings (This is after few months after diagnosis and starting medication I believe)
FT3   3.1 pg/ml
FT4   1.35 ng/dl

September 2022 readings
Total T3   80 ng/dl
FT3   2.82 pg/ml
Total T4   8 μg/dl
FT4   1.18 ng/dl
TSH   3.91 μIU/ml
TSH - Ultrasensitive   3.42 μIU/ml

February 2023 readings
Total T3   81 ng/dl
Total T4   7.1 μg/dl
TSH - Ultrasensitive  2.81 μIU/ml

[gimel]

Lab results and associated reference ranges vary from lab to lab, so to assess those lab results I need to know the reference ranges shon on the lab report for FT4 and FT3.   Total T4 and Total T3 are not very useful, so always insist on the Frees.  

It has been a while since last FT4 and FT3 tesets, so those should be done, as well as Vitamin D, B12 and ferritin.   Even more important is to assess what  typical symptoms she has currently.  Please ask her to review the following and identify which ones she has.  

Tiredness.
More sensitivity to cold.
Constipation. (needs to use laxative or fiber)
Dry skin.  (needs to use skin creme)
Weight gain.  (difficulty losing weight)
Puffy face.
Hoarse voice.
Coarse hair and skin.
Muscle weakness.
Muscle aches, tenderness and stiffness.
Menstrual cycles that are heavier than usual or irregular.
Thinning hair.
Slowed heart rate, also called bradycardia.
Depression.
Memory problems.

[abhi747]

Just trying to understand - shouldn't be the reference ranges universal, irrespective of lab, and not depending upon them? Providing below the readings as per the reference ranges in the reports available -

Feb-23
Test name                                               Value        Unit               Reference range
TOTAL TRIIODOTHYRONINE (T3) 81                 ng/dl                60-200
TOTAL THYROXINE (T4)                 7.1                 μg/dl                4.5-12
TSH-ULTRASENSITIVE                         2.81                 μIU/ml                0.35 - 4.94


Sep-22
Test name                                                                  Value Unit Reference range
TOTAL TRIIODOTHYRONINE (T3)                         80 ng/dl 60-200
FREE TRIIODOTHYRONINE (FT3)                       2.82 pg/ml 1.7-4.2
TOTAL THYROXINE (T4)                                            8 μg/dl 4.5-12
FREE THYROXINE (FT4)                                        1.18 ng/dl 0.7-1.8
THYROID STIMULATING HORMONE (TSH)        3.91 μIU/ml 0.3-5.5
TSH ULTRASENSITIVE                                               3.42 μIU/mL 0.35-4.94


Dec-21
Test name                                          Value Unit Reference range
FREE TRIIODOTHYRONINE (FT3) 3.1 pg/ml 1.7-4.2
FREE THYROXINE (FT4)                 1.35 ng/dl 0.7-1.8

Regarding symptoms, I remember her mentioning earlier that she does not experience any symptoms as such with the ongoing medication, as the required hormone is fulfilled by the medication. Isn't that natural? Or do you mean - some people experience symptoms even with the ongoing medication as well? I can confirm with her regarding symptoms, but please let me know if I should be asking about her symptoms at current times, as the medication is already going on, or symptoms when she was diagnosed (before starting the medication).

[gimel]

I will firsst try to answer your questions.  

1. Not serious if properly diagnosed and treated.
2.Most hypothyroidism is not "curable", it just requires ongoing medication.
3.If not treated adequately hypothyroidism can cause trouble getting pregnant.  In some cases the baby can be affected.
4.If TSH is 10 or above, it is overt.  If TSH is above range, but less than 10, and Free T4 is in range, it is called subclinical.  
5.With age, and without treatment,  subclinical can becomes overt.
6.Yes, if she is diagnosed and treated by a good thyroid doctor, which I will explain later.  
7.I don't know of any dietry retrictions that would apply.  There are some supplements that may be important, such as Vitamin D, B12 and  iron.

I am not a doctor.  I have suffered with hypothyroidism for over 50 years, and was improperly diagnosed and treated until about 12 years ago.  Since that time I have researched hypothyroidism extenively and written 3 papers with co-authors that included a retired Endocrinologist who has co-authored over 100 papers, many of which are about thyroid issues.  Following is a link to our latest.

https://thyroiduk.org/wp-content/uploads/2023/10/A-Patients-Guide-to-the-Diagnosis-and-Treatment-of-Hypothyroidism-V5.pdf

In preparation for reading the paper, I should point out that current standard of care is based on the ATA/AACE Guidelines for Hypothyroidism.   Diagnosis and treatment is based predominantly on a TSH test, which doesn't work for most patients.  TSH has only a weak correlation with the actual thyroid hormones, and a negligible correlation with patient symptoms, which is the starting point for patient complaints.   Good thyroid doctors who will diagnose and treat based on an evaluation for  ssymptoms typical of hypothyroidism, along with levels of the thyroid hormones, Free T4 and Free T3, are hard to find.

There is much to discuss, but let's start with all the above.

[abhi747]

Thanks, the major implication for this as I can see is only lifelong medication just like Type 2 diabetes (not sure though if the severity, complications, or risks of hypothyroid are comparable to Type 2 diabetes), let me know if there are any other implications though. I believe if T3, T4, and TSH are within the normal range with the medication,  the person is as good as a normal healthy person.