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.
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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.
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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?"

[goolarra]

I agree with both of you that symptom relief should be the goal, regardless of the labs.

Beyond that, I'd have to separate TSH from FT3 and FT4.  TSH is affected by so many things.  Any disturbance in the thyroid/hypothalamus/pituitary feedback cycle can make it useless.  Furthermore, meds, especially T3, can exacerbate its uselessness as can the length of time one has been on meds.  So, yes, I think it often creates more problems than it resolves.  I very rarely quote a target level for TSH and try to avoid much discussion of it at all unless it's unavoidable (poster only has TSH, etc.).  Full disclosure:  I have a pituitary issue, and my uncooperative TSH almost did me in, so TSH is no friend of mine.

On the other hand, I do think that some target level is useful for FT3 and FT4, since, as Sally points out, many people (myself as a newbie included) have no idea what we mean when we say "just being in range is not enough".  Midrange for FT4 is not a one-size-fits-all number, but it will give people an idea (starting point) of where most people can expect to want to be.  A caveat about individual differences is always a good idea  Likewise for FT3 levels being in the top half.  I think the midrange and upper half "rules of thumb" are illustrative of just how much into the range many people have to be before feeling well.  Once again, I break the rule here, myself, since I am very comfortable in the lower ends of the ranges.

Another point about TSH is that many people do not understand that TSH, in and of itself, causes no symptoms.  Since it doesn't correlate well with the frees, getting your TSH "right" can be totally counterproductive.  TSH can only be used to guide tratment if it accurately reflects FT3 and FT4 levels.  Once it is in disagreement, I think it has to be thrown out, which makes it kind of useless overall, doesn't it?  

[Barb135]

I have to agree with gimel and goolarra, regarding the use of TSH for diagnostic/treatment.  While TSH can be useful in the initial diagnosis - most doctors only test TSH to start with, so that's what you have to go on as an "indicator" of a problem; however, all too often, when TSH is the only test done, it's "in range" because too many labs/doctors are still using old ranges; or even if using the new range, they ignore a TSH that's on the high side.  This leaves a lot of patients without treatment, because with TSH in range, doctors don't want to test further, so often miss the fact that FT's are too low, in spite of "normal" TSH.  TSH should always be done in conjunction with FT3 and FT4.  

I am one who was initially treated, based solely on TSH and quite frankly, I thought that doctor was going to kill me.  My TSH sank to the bottom almost as soon as I started on med; therefore, my doctor kept lowering my med, in an effort to bring up my TSH back to "normal", while ignoring my low (0.6) FT4, and refusing to even run FT3.  Had it not been for a wonderful ENT who recognized what was happening and sent me to an endo, who *does* test both FT3 and FT4, I would still be a very sick woman.  

My endo and I completely ignore my TSH, which routinely runs at < 0.01- I'm not even sure why he continues to order it (habit maybe?).  As long as my FT's are good, we are happy.  I am slightly disappointed that my endo does seem to think that "in range" is good enough, but fortunately, he's open to suggestions and when I point out *how low* in the range, he will acknowledge that an increase could help alleviate symptoms.

I totally agree, that TSH, itself neither causes, nor alleviates symptoms; therefore, once a diagnosis has been made and treatment begun, a TSH target level is useless.  

In regards to the bone loss issue - there's still controversy surrounding it, but studies are showing that it is NOT low TSH that causes bone loss, but rather high levels of FT3.  Here again, I use my own experience - I have had osteopenia for many years (during some of which, I now know, I was hyper); however, in the past 2 yrs, I have actually rebuilt bone by supplementing with calcium, exercise, etc - during the entire, past, almost 3 yrs, my TSH has been < 0.01, yet I rebuilt bone.

I do think that a "ball park" level for the FT's is helpful for those just being diagnosed or newly so.  Had I not had some type of figure to aim for, I would have believed my first pcp when he said, "in range is good enough" and I would not have known to point out to my endo, when my levels are low in the range and an increase may be in order.  Again, though - once the diagnosis is made and treatment begun, the individual person has to take over and keep up with the levels at which they feel best.  While goolarra is quite comfortable at lower levels, I felt totally horrible until my levels got over mid range for both FT's.  I'm currently very high in the range for FT4 and about 75% for FT3 and feel better than I have in years.

[gimel]

Just wanted to clarify that I have no problem with a "ballpark" target for FT3 and FT4, especially when that target is based on the info we hear from so many Forum members.  I think such info is good , especially for new members searching for answers.  

I did want to point out; however that  target ranges for FT3 and FT4 are incompatible with concurrently having a target range for TSH, since TSH is dependent on the levels of FT4/FT3, and cannot be adjusted independently.    One of the reasons so many of our members have suffered from hypo symptoms is that many doctors target a range for TSH, which then dictates levels of FT3 and FT4, and many times these levels are inadequate to relieve symptoms.  Conversely when others of us have gotten our FT3 and FT4 levels adjusted adequately to relieve symptoms, we have TSH levels suppressed to the very low end of the range.  For example my TSH has been around .05 for over 25 years, with no resultant hyper symptoms, contrary to what many doctors would have us believe.  

I do a lot of reading and searching for info that might give a clue as to why the medical community is so hung up on TSH as the primary diagnostic for thyroid problems.  Some info that might lead them to have such reliance on TSH is shown in fig. 6-7 of this link.

http://www.thyroidmanager.org/Chapter6/Ch-6-9.htm

Without really understanding the statistical analysis underlying the data, many would be heartened by the high degree of correlation between TSH and FT4.  However, when you really look at the data, each correlation coefficient is for only one of three patients, as they are calculated separately for each of the three.  I guess this would be useful if you took the time and money to do 20 - 25 tests for both TSH and FT4 for each patient.  Then from a TSH test you could fairly well estimate a FT4 level for that one patient only, after all that testing and running a linear regression analysis to establish the regression line.  Hardly likely in the real world, I'd say.

When you want to extrapolate this kind of data to the general public, then that's a whole new can of worms.  For example, look at fig. 6-7 and place a horizontal line at a TSH of 2.  When you look at the corresponding FT4 level that occurred with the three patients, you see that FT4 varies from about 5.5 to 12.5 pmol/L, when total the range is typically 10.2- 19.2.  It's pretty clear from these data that the correlation of  TSH and FT4 for the general population of patients will be so poor as to be meaningless.  Yet TSH continues as the gold standard.  The data scatter is also pretty well depicted in the link in my first post above.  

If other members find data purporting to show a correlation between TSH and the actual thyroid hormones, I'd like to see it and be able to evaluate.  Sure I'm biased, but I am also willing to consider any such data.  

I hope we get lots of participation on this subject.  There is a lot to be learned all around.

[LazyMoose]

I Have been on 6 different thyroid meds or combos / brands in 2 years. Yes SIX. This was not a planned lab experiment, but kind of turned out that way. What an experience it was.  Felt like a Lab Rat for the thyroid world.

What I have learned and proved in my case:

We all need  to learn our 'target' range, and to stay there, obvious right? But all six brands I used resulted in different 'free' levels when they they were dosed to a certain TSH 'target' by an endo. Because the free levels were different. So correlation between 'FT3 and FT4 to TSH will change per brand of thyroid med used. Its not just your body, its the med to.

When I pushed to try the opposite approach, aim for a free target of known 'wellness' from the past, I felt better. But my TSH doctor was concerned, since I looked near hyper per TSH.

I have found my 'feelgood target' with thy brands that work for me is a certain FT3 target (upper third), regardless of the corresponding TSH #. This was not valid with one brand of US natural thyroid, that brand did not work no matter what did.

It seems that simple.

TSH is the curbs on a eight lane freeway. FT3 is the buildings on either side of a single lane alley.

[LazyMoose]

Note: many of us that feel best with FT3 in the upper third are also on dessicated.

Coincidentally to get FT4 even into the lower side of range when using most dessicated (pig) thyroid med requires enough med that The FT3 will be in the top third of the range.

I wonder how many on separate synthetic T3/T4 must get T3 in the upper third to feel good? Anyone here?

[Barb135]

I use separate synthetics -- Tirosint - 100 mcg (since August 2010) and generic T3 - 5 mcg.  My latest labs were Nov 1;
FT3 = 3.7 (range 2.3 - 4.2)
FT4 = 1.5 (range 0.8 - 1.8)
TSH 0.01 (highest it's been since starting med almost 3 yrs ago; TSH at dx was 55.54).  

I've struggled all this time to get my levels up and now that my FT3 and FT4 levels are up, I feel better than I've felt in years........

Even though I have to get up at 3:30 am to get ready for work, I'm finding that I don't have to go to bed quite so early; and most nights, I'm sleeping better (not waking up multiple times).  

Dessicated vs synthetic?  Meds affect us all differently, so that's impossible to call.

[LazyMoose]

Barb, In your case your known 'target' is also the frees.

Since you can adjust these individually , do you feel FT3 in upper range is more responsive to eliminating symptoms compared to FT4?

Have you ever had FT4 in the low end on range, but FT3 upper third and still felt great?

[redheadaussie]

Maybe I am just different, then again as my Endo has stated, I am Unique! I have pretty much been at the mid range for FT3 alot of the time, only in the past 18 months or so have they really started to fall.  My FT4 has usually been in the upper 3rd range.  I always feel totally crud.
If my TSH is off I feel crud. I can get the symptoms of hyper and know that my FT3 is still falling and my TSH can be for example, 0.06. If my hypo symptoms come along, I can know that my TSH will be up there and any thing over 1.0 is a killer for me.

Personally I know full well that if I were treated by just looking at my FT3 and FT4 I would be dead. If you care to see my photos and my pathology results for 3 years, I go all over the place. If you were a doctor here in Australia, and treating me just by the free's (which they don't anyway, ha ha!) you would say I was just a tad over or under but still just within range, so no need for medication! BUT looking at my TSH, which they do look at only, I am dosed according to that number.  So in a back to front way, I am glad they look at the TSHas their main concern. Of course, I would dearly LOVE for them to look at the bigger picture of all 3 tests, but they don't.

TSH being a pituitary hormone to thyroid trigger hormone is still a very important tool to use in the bigger picture, in my opinion. Without knowing how much stimulation is being sent to the thyroid which in turn triggers the T4 production,  how can we be aware of how the feedback loop is working?

When the TSH is released it goes to the thyroid to tell it to make some T4. If that is off then the thyroid's response to producing T4 is not going to be optimal, and therefore the T3 is not going to be great either.  So it is very important to use all of them together to see the bigger picture.

Dismissing the TSH totally is like saying you can run a car without petrol. Without it there is no going anywhere! Same as the thyroid, without that hypothalamus releasing TRH to the pituitary to release TSH the whole shebang would fall over.

Yes the T4 is important too. This tells us our thyroids are producing what they should be. For those of us without thyroids this allows us to see if our medication is actually at the level it should be so that the production of T3 can be made in our bodies. (Not all of the conversion happens in the thyroid, contrary to popular belief)

One of the main issues still contested is the fact that those rotten reference ranges are an averaged mean of a small number of the population. This mathematical formula is a generalisation, which should not be used for individuals. It was meant to be a guide as to where most people ought to be in the so called normal range if not being treated or having any thyroid disease in the first place. Obviously those studies are flawed in saying that Mrs Jones who has a FT4 say of 18  which is mid-range in Australia is perfectly normal, when she feels lousy, hyper and totally miserable. Her doctor says 'No problems here,  your thyroid is producing within the normal levels of others in society. Off you go'. But her TSH is say at 0.05 which is out of range in Australia and she would be treated. YET if her TSH was say, 0.40 and she was still complaining of the same symptoms at this imaginary same visit, her doctor more than likely would say, "Well you are just above the lower range, but still in the normal for society, so off you go." (0.35 being the lower range here in Aus)

So in that case, just looking at her FT4 on it's own is useless.  To be continuesd!!
  

[LazyMoose]

Interesting. I would be sick if I aimed for a target TSH. I can see its usefulness as a very general guide for detection, but even then its not accurate. This may differ as world TSH ranges differ.

You are able to treat and know your target range based on TSH possibly if you have been on one brand of med for years. A 'target' or 'sweet' TSH value will change from med brand to med brand in one person, I unintentionally proved this. So TSH is not a constant or reliable value for fine tuning.

An interesting fact I would like to point out in my experience of using 6 brands in 2 - 2-1/2 years. The common denominator of lab values from these brands when ever I felt good was free levels, not TSH.

***My point in my case is that my target TSH to feel good on these 6 different brands varied, never the same. The free levels and maybe the ratio of t3/t4 for me to feel good was not very different.***

Info above is about the closest to a scientific 'test' I have read on this forum. (LOL) But I have only been here under 2 years.

My 'feelgood' TSH value varied because the correlation of TSH to Frees varied brand to brand.  The common denominator lab value which corresponded to my feeling well was specifically a certain upper third Free T3 range within the range - along with FT4 somewhere in range.

[LazyMoose]

In my case, I was sickly hypo for 10 years while being treated and tested solely by TSH, and the old US range.

Ten years wasted. Thats what led me to this forum.

[redheadaussie]

..continued..Sorry guys we had a major thunder and lightning and heavy dump of rain, so had to put the computer to nigh nighs.

For me, not being able to get any other type of T4 medication other than Eutroxsig in Australia (Oroxine being the generic and identical product) makes it difficult to be able to note any variance in the whole TSH, FT4 etc trip. Yes, it does lead to consistency in results though.

I often see the Americans who post say they feel better on such and such a brand. There tends to be a consensus on that by others who all seem to do better on Brand X instead of Brand A. It would be very interesting, and my engineering friend came up with this idea, of having everyone do as I did, make a type of spreadsheet with Date started medication, the date of blood draw, the TSH etc and the ref ranges. It would be great to be able to put all that in some kind of database and then see what results are noted and at what point most people find they feel the best. I bet it is nothing like the so-called reference range tell us to be!

I wasn't saying that I am aiming for a sweet spot TSH, rather that I feel better at a certain level than at others!BUT only if my Frees are in any sort of normal range, which 80% of the time they are not. As I said earlier I am a bit different to the usual cases and this is still an ongoing battle for me to find anyone who can explain why I go hyper on low doses and hypo on higher.  For me if I was treated just on my Free's I would have a heck of a time living for very long.

The Free T4 shows that the body is producing pro-hormone and the Free T3 shows it is being utilised. How well that system is working is a highly individual thing, and that is where the reference ranges are often useless. I have been fighting this illness for over 20 years now, and I am tired of being told my levels are just over or just under and nothing to worry about. I have symptoms, dear doctor, not numbers, and I would like to feel better.

I was never treated solely by TSH even though it was obvious something was wrong. Our doctors here would even refuse testing for that. Unless you walked in with a raging goitre, it was never 'allowed' unless 'clinically suspicious' for testing. I had only 3 thyroid tests done in near 10 years and even then I had to cry (literally) to get them and when I got the results it was only TSH anyway!  Which was only 'just' slightly above the lowest range!  Even if they had just treated me by TSH alone with all my raging hyper symptoms at the time, I would not have lost my kids, my home, my job, my relationships. 20 years later I am still fighting the stupid mentality of ref ranges mean you are ok.

20 years of my life wasted, and still wasting. Gah!

[Super_sally888]

Hi Everyone,

For the sake of discussion, here's my beliefs from much reading, person, and many years observation on this forum:-

1. TSH should always make reference to the 'updated ranges' of normal being in approx. range of 0.5 - 2.5.

2. TSH is a good general screening tool for people who are not on any thyroid medication at all.  I even believe it is of itself adequate in the 'non-symptomatic' population for screening purposes.

3. However, the key word here is 'non-symptomatic' population.  If someone comes to the doctor, has every symptom in the book (for hypo or hyper), then a full thyroid panel should always be done.

4. For people who are symptomatic, FT3 and FT4 should always take priority over TSH.  Thyroid issues should not be ruled out in 'symptomatic' people unless FT3/FT4 are close to mid range.

5.  I believe that a high TSH should nearly always be treated as meaning hypothyroid.  However, a very low TSH does not necessarily mean hyperthyroid, unless the levels of FT3/FT4 and the symptoms clearly show that.

6. Some people it seems do fine using TSH to monitor their thyroid levels and adjust meds.  I think this is ok so long as they feel good and have no symptoms.  Annual checks of levels is also fine once they are stable, providing there are no symptoms / they feel good.  

7. However, for people who have been on thyroid meds for any length of time TSH can become inadequate for monitoring.  IN these people their levels should be monitored on basis of FT3 / FT4 targeting levels at least mid-range as a starting point, and then tweaked from there to a level (within the range - for what that range is worth) but where they feel good and no symptoms.

8. I also believe that T4 only meds are overused and that many people will feel better on a properly dosed T3/T4 combo or a dessicated thyroid product.  

9.  Initial adjustments of meds when just starting thyroid meds can use TSH for gross adjustments, but finetuning must then be done based on how the patient feels, and finally using Ft3/Ft4.  The ranges are pretty broad and it is important to find out where an individual feels best.

10. Thyroid is not a condition where patients can just trust their doctor to prescribe a drug and they will be well (nothing like taking an antibiotic for a bug).  It is a long-term condition where the patient and doctor must work in partnership.

11. There are non-thyroid conditions that can be mistaken for and/or exacerbate thyroid conditions.  These include anaemia (low iron / low B12, vitamin D deficiency, PCOS, among others.  These should be screened for an treated appropriately, as part of thyroid management.

In Summary:-

There is no one size fits all.  

Realistically and cost-effectively, the minimum tests to get get the most reliable results should be used.  How a patient feels is at least as important, but often more important than blood work results. Symptoms and blood results should be used together.  

TSH is a useful tool, but it is the least important in long term and symptomatic thyroid patients.

I think there can be testing / symptom algorithims / flow charts to guide treatment.  This flow chart would rely both on blood levels and symptoms.  It would also consider some alternatives for checking if thyroid levels were apparently ok, but the patient still had symptoms in the face of apparently ok blood work.

I think we all actually agree, but there are shades on that agreement and slightly different emphases between us all.

[Barb135]

No, I've never had low FT4 and high FT3 - at diagnosis, my FT4 was 0.6 (range 0.8 -1.8) and my doctor refused to test FT3, but when I got it done on my own, prior to finding my endo, it too was low.  

Here's my argument AGAINST the use of TSH:  as soon as I was started on med, my TSH hit rock bottom (< 0.001); pcp panicked and swore that I was hyper, in spite of the severity of my symptoms; so he started backing down on my med, totally ignoring the fact that my FT4 was still not even in range yet.  As I said before, I literally thought this man was going to kill me.  He had me almost completely off med, simply trying to get my TSH to come back up.  At one point, he did finally realize that I was still hypo, in spite of the TSH and gave me back SOME of the med, but not nearly enough.  

My FT4 did finally start coming up a bit, but when I got FT3 tested on my own, it was still very low.  That was the point it was decided that I don't convert well and the cytomel was added by my endo.  

I started out on Synthroid, then went to generic T4 and am now on Tirosint - my TSH has remained very low regardless of the med; however, my FT3 and FT4 have responded best to the Tirosint/generic T3 regime.  While the dessicated meds are great for some, and I would never put them down,  I, personally, would be terrified if I had to switch to one at this point, or even go to a compounded T4/T3 combo, because I seem to more sensitive to the T3 med.  

In regards to the TSH telling the thyroid to produce hormones - in those of us who no longer have a thyroid or whose thyroid no longer produces hormones, so we are dependent on the supplements, TSH makes no difference.  The pituitary can "talk" to the thyroid all day long and the thyroid can not react; the "response" must come from the supplements we take on a daily basis.  

In some cases, a high TSH "could" be an indication of being hypo (particularly in undiagnosed or newly diagnosed cases), since the pituitary is calling for more thyroid hormones; that's when an increase in med would be appropriate, but ONLY, in conjunction with FT3 and FT4 monitoring.  Remember, there are those whose TSH does not come down, even with adequate FT3 and FT4; just as there are those of us whose TSH will not come up.  

Let's also keep in mind that very little of the conversion from FT4 to FT3 is done in the thyroid; the majority of it is done in the liver, as well as other organs.  

TSH should never be looked at alone; nor should it be used to diagnose/treat a thyroid issue.  I also think a "target" TSH is counterproductive, since it seems that most of us must have our FT's adjusted properly in order to feel well, and this rarely happens when one targets TSH.  

[goolarra]

I'd just like to re-iterate that a high TSH should no more be taken as confirmation of hypothyroid than a low TSH is of hyper.  My TSH hovers around 20 (due to a pituitary resistance issue), but I am euthyroid.  The danger of assuming high TSH means hypo is that you can be killed FAST with overmedication.  

I do think we're all saying that when TSH accurately reflects FT3 and FT4 levels, it can be an appropriate diagnostic.  However, we all also acknowledge that in many cases it completely fails to reflect FT3 and FT4.  We then ignore TSH.  I guess my point is:  why have to wonder if TSH is reliable or not?  Why not directly measure thyroid hormone levels?  If we throw it out the minute it doesn't conform, what good is it?

I think the main reason TSH survives as the gold standard of thyroid diagnosisis is as an anachronism.  It USED to be the most reliable method of diagnosis when free testing was more expensive and less reliable.  Doctors are still relying on what they learned in med school and are, unfortunately, teaching the next generation the same methods.

An alternative TSH analogy:

Do you judge the temperature of your house by the temperature your thermostat is set at (TSH)?  What if your oil tank runs dry (not enough FT4)?  What if something in your furnace fails so that the oil is not being converted to heat?  Do you want your HVAC tech coming to your house, saying, "Look!  Your thermostat is set right at 70-degrees.  That's right in the middle of the 68- to 72-degree range most people are comfortable in.  There's nothing wrong with your heating system.  Go put a sweater on."  (Or, better yet, "Go have your thyroid tested...you seem cold-intolerant to me!"  LOL)

No, you don't do any of that.  You judge the temperature of your house by how warm you feel in it (symptoms) and what the actual temperature of the room is (FT3 and FT4).  And if you're smart, you take the actual temperature of the room from a source independent of your thermostat, which could be faulty.  

There's no replacement for having FT3 and FT4 tested every time you have blood work from the moment you are diagnosed.  If you track those carefully along with symtoms and doses prior to labs, you establish your own personal history.  Comparing yourself to YOURSELF is infinitly more valuable than comparing yourself to a population range.  

[gimel]

I have found this article to worthwhile reading about FT3, FT4, and TSH.

http://www.drkaslow.com/html/thyroid.html

[Super_sally888]

Nice article.

I particularly like the part that response to therapy is the best indication of a thyroid problem!

So many doctors refuse to treat thyroid.  What is the issue with a low dose of thyroid meds (with monitoring)?  25 mcg of thyroid med is not going to cause any major problems but it may help.

My little sister had a nervous breakdown a year ago.  Now diagnosed with bipolar.  She suffers extreme fatigue.  She was also diagnosed with 'subclinical" or 'Compensated' hypothyroid.  This is in Australia.  Her GP and psychiatrist refuse to treat her thyroid saying it is not necessary. She believes them, despite how she feels.  I have thyroid failure, at least 2 of my other sisters are borderline (but treating with thyroid support supplements for now), which is fair enough as they don't have symptoms.

But my little sister is not borderline.  This is a  health and quality of life issue.  I am fuming mad at this situation.  But I live on the opposite side of the world.  I can't do much but rave gently (I don't want to drive her away - she gets very defensive.).  My other sisters and I are trying to get her to another doctor who we know treats thyroid appropriately.  This affects our whole family and seeing our youngest sister in this state, which we know is treatable.  This has been going on for a year now. She has finally agreed to see this doctor.  Hope it's going to get t hings moving in the right direction.

[stella5349]

Gimel,

everytime I try to load your original post - much of it vanishes and I can't read it. Is anyone else having this issue?

[stella5349]

its like its bugged?!?!?!?

[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]

Thanks.

I see it now and will take a look.

Found this too late this morning.

[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.—

[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]

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

[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