What is the value of TSH Test vs. FT3/FT4

[gimel]

Super Sally and I have had discussions about the usefulness of the TSH test and whether it should continue to be part of diagnosis and treatment of hypo patients.  For background I have copied our posts below.  I'd like to invite members to freely provide their opinions and experiences relating to these three tests.  I'd also like to invite members to provide links to any scientific data they have seen that either supports or questions the utility of TSH, or FT3, or FT4.
___________________________________
by Super_sally888
, Nov 29, 2010 07:14AM
Hello,

the correct dose of thyroid is different from person to person.

It sounds that 25 mcg is too low.

I don't know if 75 mcg is suitable.  To tell, you need to take that dose consistently for at least 4 - 6 weeks and then test TSH, FT3, and FT4.

TSH should be in the range of 1 - 2, and FT3 and FT4 should be about middle of the reference range, or a little higher.  Meds need to be adjusted (usually by adding 25 mcg/day, or sometimes 25 mcg additional every second day).

A TSH of 7.0 is still too high.  If you've been taking the 75 mcg for at least 4 weeks at that dose, then you may need an increase to 100 mcg.

Changes can only be made about every 6 weeks, because this is how long it takes for levels to stabilise after each change.

HOpe this helps.

by gimel
, 10 hours ago
To: Super_sally888
I don't really understand giving  a target range for TSH, freeT3 and freeT4.  Isn't the real target the relief of symptoms, which has to be accomplished by adjusting levels of the biologically active thyroid hormones,  free T3 and free T4?  

Yes, it is true that symptom relief frequently requires that FT3 and FT4 are adjusted into the middle of the range or higher;  however, since TSH is directly dependent on feedback to the thyroid glands from the hypothalamus/pituitary, which data that I have seen shows that TSH is affected mainly by FT4, then you cannot adjust FT4 and TSH independently.   So a separate target level for TSH may possibly be confusing to a new member.   In fact, once a patient is taking thyroid meds based on testing and adjusting levels of FT3 and FT4, in most cases, I'm not convinced of the utility of a repeat TSH test.  It probably causes more problems than it solves.

In fact, when I look at TSH data like shown in fig. 2 of this link, I have a hard time finding any enthusiasm for TSH testing at all.  LOL  I think we'd all be far better off being treated clinically and by testing for FT3 and FT4.  

http://optics.merck.de/servlet/PB/show/1809250/Thyroid-Inter-3-2008.pdf

Super_sally888
, 8 hours ago
To: Gimel
Hi,

I certainly agree that patient's meds should be adjusted based on symptoms.

I also think that target blood ranges are also very useful as a starting point for people like rajbir687 who are learning about thyroid and how it should be managed.

Getting numbers to within the ranges stated (with priority given to FT3 and FT4 levels) is a good starting point and things can be tweaked from there.  It won't work for everyone, but it will work for the majority.

Let's face it, most doctors still treat based on TSH alone.  So, at least don't go against these doctors - but instead encourage more comprehensive testing, particularly in cases where the symptoms don't match the bloodwork.  We want to encourage people coming to this forum to work with their doctors.

I am one whose bloodwork on TSH is far from that target - it is very low even while FT3 and FT4.  Honestly, even Dr. Lupo on his expert forum repeatedly says that TSH should be used to guide treatment - he doesn't seem to pay much attention to FT3 and FT4 as long as they are anywhere in or close to the range. Given this,  I am constantly questioning myself about this.  Particularly as I may have bone loss.  Should I dramatically reduce my meds and try to get the TSH up?  I am trying to have another baby now, so not time to play - but will have to play later.
____________________________________________________________

I'd like to start the discussion by pointing out the data in the link referenced above and ask "How can anyone possibly have any confidence in TSH as a diagnostic when there is this much data scatter, among patients with no known thyroid issues?"

[gimel]

Another nail in the coffin for TSH.  Also good reasons to use FT3 and FT4 tests mainly as markers for clinical treatment, rather than as diagnostics., by which to determine the need for treatment.

http://sz0102.ev.mail.comcast.net/service/home/~/KratzschNewRefRange.pdf?auth=co&loc=en_US&id=135360&part=2&disp=a

[gimel]

You know, I was just thinking.  We go to the doctor because we know when we are sick and need help.  In general, the doctors don't want to rely on symptoms as a basis for diagnosis and treatment. unless it is for something like depression or bipolar. They don't have reliable tests for illnesses like those,  so they use symptoms and patient interviews, and then they are willing to prescribe a lot of different drugs, some of which are very scary.   But for thyroid symptoms, doctors don't want to prescribe even therapeutic trials of the much more benign thyroid meds, unless they confirm it by comparing blood test results to their so-called "normal" ranges.  

Yet we know just how flawed those ranges are.  They are so flawed, that if you look through the info in studies such as these links below, it seems pretty clear to me that you cannot reliably determine if most patients' test data indicates thyroid problems or not.  There is absolutely no validity to using the usuall thyroid tests to diagnose a thyroid problem, unless the tests are TPO ab, TG ab, or TSI.  Even after diagnosing a thyroid problem as autoimmune related,with one of these,  you are right back to the problem of how to treat it.  At that point you still have the question, should it be based on blood tests and reference ranges, or should it be based on symptoms?  

So maybe we might all be better served by using some sort of thyroid checklist and rate ourselves for severity, for each symptom and take the checklist to the doctor, along with one of the many good examples from the links above that show how hopeless it is to try and diagnose by lab tests.  Maybe this approach could persuade the doctor to treat us clinically, by testing for FT3 and FT4 to establish a baseline,  and then prescribe meds adequate to eventually relieve those symptoms.  


http://sz0102.ev.mail.comcast.net/service/home/~/NACBthyroidStandards.pdf?auth=co&loc=en_US&id=135180&part=2&disp=a

http://sz0102.ev.mail.comcast.net/service/home/~/FraserNoTesting.pdf?auth=co&loc=en_US&id=135360&part=3&disp=a

[Barb135]

goolarra explained it pretty well.  In my case, I'm on Tirosint, which is a T4 med; in addition, I don't convert T4 to T3 well, so I'm also on a small dose of T3 med to bring those levels up.  I don't even look at the TSH.  

There is no medication that will specifically adjust TSH.  It's "assumed" that when one is on thyroid replacement, as the FT levels go up, the TSH will go down and automatically stop somewhere in the range - as you can see, it doesn't necessarily work that way. TSH, in and of itself, does not cause or alleviate symptoms; in my case, we could save $ if we stop testing it, because we know it's going to be < 0.01.  I've had doctors try to "normalize" my TSH - they only kept me ill.

In goolarra's case, her TSH runs high, therefore any doctor trying to lower it, would make her very ill.

When TSH no longer reflects FT levels, it should be ignored.
***********************************************************************************************

In regards to the findings in UK - we can see how well that works by the members who live there and have to jump through hoops to even get the FT3 testing.  I find it very scary to think they would "assume" that all patients on replacement therapy would do well on a dose of 100-200 mcg/day, or that most patients would be euthyroid on 100-150 mcg/day.  I also find it ironic that they even "suggest" treating by clinical response, when we can see that most of their doctors, clearly, don't even really consider symptoms; they look only at TSH.  

Could something like this be what we have to look forward to, here in the US?  Too much like "flying by the seat of your pants"............

[goolarra]

In theory, you take one med which raises your FT4, that in turn raises your FT3 and lowers your TSH.  In reality, some people are slow converters and have to take a direct source of T3 to feel well.  For any number of reasons, TSH can be, and often is, a very unreliable diagnostic of thyroid status.  If anything goes awry in the thyroid/hypothalamus/pituitary axis, TSH can be affected.  Many find that TSH has to be suppressed to very low levels (often approaching zero) before FT3 and FT4 are high enough to relieve symptoms.  I have a pituitary issue, and my TSH hovers around 20.0 most of the time.  So, it goes both ways.

Your FT4 is too low in the range.  FT3 and FT4 ranges are tainted because the original population that made them up included many undiagnosed hypos.  The whole bottom half of the range is questionable.  TSH range was "corrected" several years ago, but the free ranges have never been changed.

[gimel]

Other patients, including you, would receive further adjustments according to your clinical response.  LOL

I think it is incredible that the British Medical Journal would be recommending less testing and more clinical treatment for symptoms.  That is totally at odds with the way they generally treat thyroid patients in the UK.  They seem to resist all testing other than TSH.  Then if the TSH result is not into double digits they think everything is okay and your symptoms are "somatoform disorders".   (Only slightly exaggerated)

[sunflower642]

I am only on here for a few days so this is confusing to me.  Are you all saying that you would take separate meds for each category?  If your TSH was too low, like Barb135, you have to take another med to keep your FT4 and FT3 at another level?  Am I understanding that correctly.  Or will one medication affect all 3 categories and you just wait?
Also, when I was diagnosed my TSH was 6.97 (.34 - 5.60) and FT4 7.08 (6.09 - 12.23).  So since my TSH is out of range but FT4 in range, I possibly may not by hypo?  Will both be out of range when you are hypo?

[goolarra]

OMG, major groan..."most patients"...what about the rest of us?  Can you imagine what would be happening if diabetes were treated with the same principles?  This is depressing.

[gimel]

Here's an interesting bit from a study in the British Medical Journal.

"A question that remains to be answered convincingly is whether it
is clinically necessary to measure thyroid hormone concentrations in
patients receiving thyroxine replacement. The standard replace-
ment dose in Europe and America was 200-400 mcg a day until 1973,
when it was halved to 100-200 mcg a day on the basis of biochemical
measurements of thyroid hormone concentrations.   We are not
aware of any study that has shown that this reduction in the standard
dose has had any clinically beneficial effects. Different groups have
shown changes in sodium metabolism,'9 hepatic enzyme activity in
serum, and systolic ejection time intervals' in patients receiving
high doses of thyroxine, but such measurements have not been
shown to be of any relevance to patient care.


"We consider that biochemical tests of thyroid function are of
little, if any, value clinically in patients receiving thyroxine
replacement. Most patients are rendered euthyroid by a daily dose
of 100 or 150 mcg of thyroxine. Further adjustments to the dose
should be made according to the patient's clinical response. In our
laboratory 36% of all thyroid function tests are performed to
monitor thyroxine replacement. To stop doing these tests in such
patients would cause considerable saving in the costs of reagents in
laboratories using commercial kits."
_________________________________

Unfortunately. from what we hear from the UK, they seem to have continued with testing, but predominantly only TSH, and they don't want to treat patients clinically (for symptoms).

[gimel]

Here is another interesting item.

21.9% of patients with Thyroid FunctionTests within the reference ranges were found to have inappropriately low TSH indices indicating pituitary dysfunction (Jostel 2009)

Not very encouraging for patients being diagnosed by TSH alone.

[gimel]

Here is more good info from the link I noted previously.




Kratsch 2005: Attempt to redefine Ref. Ranges with carefully screened population of healthy blood donors. No symptom questionnaires. 95% TSH range for the most carefully screened group: 0.04-3.77mIU/L,  95% free T4: 0.99--1.6 ng/dL, most labs report 0.7-1.7,  95% free T3: 2.6-4.4 pg/mL. Most labs 2.3-4.2)  Median Free T4 for males- 1.32 ng/dL. Median free T4 for females 1.2 ng/dL. Median free T3 for males 3.4 pg/ml, Median free T3 for females 3.1 pg/ml. Median TSH for males and females were 1.35 and 1.42. Notice that the free hormone ranges have higher lower limits. Many, many symptomatic “normals” have free T4 below 0.99! The upper range is lower than usual RR for free T4 but a bit higher for free T3. Question remains—On what basis can one claim that every person within the 2.5 to 97.5 percentile range is therefore “normal”? What if they are low in the range (say at the 5th percentile and are symptomatic?

________________________

Note the significant differences between their findings on ref. ranges, compared to the ones we see every day.  I am not talking about the averages but the breadth of the ranges.

[HessyKat]

Bless you gimel in your endeavor to bring some kind of awareness with these thyroid issues. I wish you much luck with the Surgeon Generals office. I have been so frustrated with the thyroid treatment for years. I was dx. with Graves and Hashimotos at the age of 21yrs old and I still battle to find some kind of relief from my symptoms. Here I am 48yrs old now and it has been a long journey.

[LazyMoose]

1)Power in numbers has proven to be the ONLY way for any change in this country, the power of true representation - its true, think about it. Individuals mean nothing.

2)Like gimel said, who do we aim our campaign at? There is not one obstacle, many, and widespread.

3)I think the other forums need to be on track to, they all must have some small hand full that are 'doers'.

4)I don't think this type of post should just disappear, it needs to be on top with the 'welcome wagon' for others to take note. This post was about TSH / Frees,........ the subject has changed. We had several posts on thyroid awareness. We need one on a thyroid treatment campaign. - exactly to the point. Just being aware does not mean proper treatment / Dx'ing.

The new 'Thyroid Coalition', was supposed to be a representation of all of us for these purposes as I understood. So far its just a very nontechnical face book thyroid page that provides less information than this forum, seems to be more about emotional support with thyroid disease. Currently its a disappointment, as we don't gain any ground from another forum. Maybe it will change? I hope so.

We do need to attempt to change thyroid treatment on a National level. A talk show always stirs things up. But who would represent us there? And magazines, it might be a liability thing with them - they want Drs in there stories, not what some patient thinks - I understand their view.

Surgeon General - good idea!

[gimel]

We wouldn't even know who to petition.  No single group seems to have any real influence on what is done by the labs and doctors, as evidenced by the lack of compliance with the 8 year old change in TSH reference range.  It is just a self perpetuating mess that we all have had to overcome in any way possible.  

It seems to me that if there is any possibility of there being one place that could potentially do what is needed, it would be the U. S. Surgeon General's Office.  With all their concerns and publications about the epidemic of obesity, you'd think that sooner or later they would discover the impact that hypothyroidism has on metabolism and weight problems, and that this might lead them to some action on thyroid problems.  but then if they just go by the current practices and guidelines of the medical community, how would they even know of the extent of the problem?  I have read that in the UK, thyroid patients there got so fed up with how they were being misdiagnosed and improperly medicated, they started pressuring their Government reps to do something about it with the National Health Service.  

As I mentioned, I've tried once to get to someone in the Surgeon General's Office.  All this has inspired me to give it another go.

[Barb135]

Power in numbers??  Any way we could get a petition going?  

[LazyMoose]

The problem is that no one will ever listen to individuals that are not doctors themselves.

Just like anything else, you need a related title or the power in numbers to get them to listen.

[gimel]

I wish I could give you a good answer for that, but I can't.  I've been communicating with the AACE since early this year, asking these kinds of questions and providing links to info such as this.  I questioned why TSH remains as the primary test.  I questioned why the ranges for FT3 and FT4 have never been corrected as was done for TSH over 8 years ago.  In the absence of that I questioned why they don't strongly advise their members to consider FT3 and FT4 ranges as guidelines within which to adjust levels as necessary to relieve symptoms.  Basically their response was that their ranges were evidence based.  So then I provided a lot of links to data supporting my questions and asked them for references to info that supported their "evidence based" ranges.   They pretty much blew me off by saying that I should withhold any further questions until they republish their guidelines sometime later.  

I'm not really sure the AACE is the best place to be talking with, since they don't really seem to have any great influence over labs and doctors.  I say this since most labs and doctors are still using the old TSH range 8 years after the AACE recommended it be changed.

I also emailed a major thyroid pharmaceutical company and gave them all this good info and asked why they didn't take it on and try to influence the medical community to change.  It would be to their benefit, since many more patients would be getting thyroid meds.  No response.

I even went to the top.  Oprah.  I tried to get an email to her suggesting that her weight problem was a result of poor diagnosis and treatment of a thyroid problem and that she could help millions of people like herself by doing a show on all this.  Nada.

I tried to make contact with the Surgeon General's Office.  No luck.  I feel like Don Quixote.   LOL


Any suggestions?

[LazyMoose]

Clicking on "Dr. Lindner's thyroid hormone abstracts." at the bottom of the page leads to endless info. A lot there.

I wonder why the AACE fails to recognize this and continues to preach TSH ranges, when there have been studies on this.

This really erks me.

[gimel]

I understand there might be a problem getting to the link in the way I suggested.  Try this instead.  It is really worth reading.

http://www.hormonerestoration.com/files/Thyroid.doc

[gimel]

Yes, I do.  I found these fascinating bits of info and lots more when I clicked on the link shown at the bottom of this link.  

http://www.hormonerestoration.com/Thyroid.html

[LazyMoose]

Kabadi 2006  (Therefore using T4 to suppress TSH assures that there will be less conversion of T4 to T3 than in the normal euthyroid state.  An explanation for why T4 replacement therapy without T3 is not adequate.—

- gimel, have a link to this?

[gimel]

During some of my random reading about thyroid subjects, I have found a treasure trove of information accumulated by a doctor.  Each of these items I have posted below has a reference as to its source, so it is not just someone's opinion.  This is very interesting stuff, I think.
_________



“Normal” TSH and free T4 do not determine existence or non-existence of hypothyroidism or of response to thyroid replacement. 139 people with normal blood tests but hypothyroid symptoms responded very well to thyroid supplementation. See Skinner below.
“In the future, it is likely that the upper limit of the serum TSH euthyroid reference range will be reduced to 2.5 mIU/L because >95% of rigorously screened normal euthyroid volunteers have serum TSH values between 0.4 and 2.5 mIU/L.” (Spencer and Demers NACB report )
Patients on suppressive doses (TSH <0.01to 0.6mU/L) of T4 have total T4 levels 50% greater than controls, but total T3 levels were identical to controls, and there was only a small difference in symptoms and cardiac parameters.  Shapiro 1997
Thyrotropin (TSH) may promote both the conversion of T(4) to T(3) and metabolism of rT(3) into T(2) in nonthyroidal tissues via enhancement of the same monodeionase.  Kabadi 2006  (Therefore using T4 to suppress TSH assures that there will be less conversion of T4 to T3 than in the normal euthyroid state.  An explanation for why T4 replacement therapy without T3 is not adequate.—

[stella5349]

Thanks.

I see it now and will take a look.

Found this too late this morning.

[gimel]

I don't know Stella.  No one else has mentioned having a problem.  Here's the whole post again.

Super Sally and I have had discussions about the usefulness of the TSH test and whether it should continue to be part of diagnosis and treatment of hypo patients.  For background I have copied our posts below.  I'd like to invite members to freely provide their opinions and experiences relating to these three tests.  I'd also like to invite members to provide links to any scientific data they have seen that either supports or questions the utility of TSH, or FT3, or FT4.
___________________________________
by Super_sally888
, Nov 29, 2010 07:14AM
Hello,

the correct dose of thyroid is different from person to person.

It sounds that 25 mcg is too low.

I don't know if 75 mcg is suitable.  To tell, you need to take that dose consistently for at least 4 - 6 weeks and then test TSH, FT3, and FT4.

TSH should be in the range of 1 - 2, and FT3 and FT4 should be about middle of the reference range, or a little higher.  Meds need to be adjusted (usually by adding 25 mcg/day, or sometimes 25 mcg additional every second day).

A TSH of 7.0 is still too high.  If you've been taking the 75 mcg for at least 4 weeks at that dose, then you may need an increase to 100 mcg.

Changes can only be made about every 6 weeks, because this is how long it takes for levels to stabilise after each change.

HOpe this helps.

by gimel
, 10 hours ago
To: Super_sally888
I don't really understand giving  a target range for TSH, freeT3 and freeT4.  Isn't the real target the relief of symptoms, which has to be accomplished by adjusting levels of the biologically active thyroid hormones,  free T3 and free T4?  

Yes, it is true that symptom relief frequently requires that FT3 and FT4 are adjusted into the middle of the range or higher;  however, since TSH is directly dependent on feedback to the thyroid glands from the hypothalamus/pituitary, which data that I have seen shows that TSH is affected mainly by FT4, then you cannot adjust FT4 and TSH independently.   So a separate target level for TSH may possibly be confusing to a new member.   In fact, once a patient is taking thyroid meds based on testing and adjusting levels of FT3 and FT4, in most cases, I'm not convinced of the utility of a repeat TSH test.  It probably causes more problems than it solves.

In fact, when I look at TSH data like shown in fig. 2 of this link, I have a hard time finding any enthusiasm for TSH testing at all.  LOL  I think we'd all be far better off being treated clinically and by testing for FT3 and FT4.  

http://optics.merck.de/servlet/PB/show/1809250/Thyroid-Inter-3-2008.pdf

Super_sally888
, 8 hours ago
To: Gimel
Hi,

I certainly agree that patient's meds should be adjusted based on symptoms.

I also think that target blood ranges are also very useful as a starting point for people like rajbir687 who are learning about thyroid and how it should be managed.

Getting numbers to within the ranges stated (with priority given to FT3 and FT4 levels) is a good starting point and things can be tweaked from there.  It won't work for everyone, but it will work for the majority.

Let's face it, most doctors still treat based on TSH alone.  So, at least don't go against these doctors - but instead encourage more comprehensive testing, particularly in cases where the symptoms don't match the bloodwork.  We want to encourage people coming to this forum to work with their doctors.

I am one whose bloodwork on TSH is far from that target - it is very low even while FT3 and FT4.  Honestly, even Dr. Lupo on his expert forum repeatedly says that TSH should be used to guide treatment - he doesn't seem to pay much attention to FT3 and FT4 as long as they are anywhere in or close to the range. Given this,  I am constantly questioning myself about this.  Particularly as I may have bone loss.  Should I dramatically reduce my meds and try to get the TSH up?  I am trying to have another baby now, so not time to play - but will have to play later.
____________________________________________________________

I'd like to start the discussion by pointing out the data in the link referenced above and ask "How can anyone possibly have any confidence in TSH as a diagnostic when there is this much data scatter, among patients with no known thyroid issues?"

[stella5349]

its like its bugged?!?!?!?