Re: Normal Values of T4 etc.

[Guest guest]

Hi , you are very fortunate with your GP. Maybe we should have a list of GPs who will (unless there is one and Ive missed it!

If you find anything on the TSH normal distribution please share it as its something Ive been looking to - Im not a statistician but my understanding of a normal distribution is that 95% of (in the case of TSH) people would fall within that distribution and therefore 5% would fall outside it! I think this would be a useful addition to the BTA response papers but Ive not been able to find it either, or where the TSH range came from in the first place - so if anyone has any info on this I would be pleased to hear from you.

thanks,

Gill

[Guest guest]

Hi Bob

I am so pleased you appear to have a good GP who recognises hypothyroidism as a disease, rather than depression. I am also happy that you appear to be doing very well on Levothyroxine and hope you continue to do so. How long is it since you were properly diagnosed?

The problem of sufferers getting a diagnosis and therefore treatment (and we want a choice of treatment) is horrendous, and it is a fact that it is organisations such as the British Thyroid Association who hold the reins - and the whip (

It is a fact that the problem with the reference ranges has not been properly addressed and hopefully, another study will one day be carried out into these. I personally think the next thing to be addressed is the TSH range, as this is enormously controversial. After I have completed the comments to the BTA on their statements on Armour and T4/T3 combination therapy, I will, hopefully, try to put something together as we need to get all medical practitioners involved in further discussion. The TSH reference interval in America is 0.3 to 3.0 - and in Germany it is 0.5 to 2.5. In the UK, the last guidelines say it is 0.5 to 10, and BTA state that patients should not be treated unless it is outside the top of the range. Most endocrinologists have a personal cut-off point of 5.0, but this controversy has to be looked into, and quickly.

Welcome to the forum, I hope you get all the help and support you need. It is interesting that we are recently getting quite a lot of men as members. I wonder if there is a reason for this, as it is mainly women who suffer this disease.

Luv - Sheila

> > One point that came out in my researches during the hospital period> was that the Normal ranges are statistical normal distribution curves> based on samples. Now clearly one fit person can have a normal T4> reading of 17 while another has one of 11. Both are within the> reference range and hence normal. If the first has a reading of 10 [> just inside the reference values ]when ill that person may be equally> as ill as the second person with a reading of 4 which is well outside> the reference values. I've not been able to find any references to> this in my researches and it seems to be a vital point when it comes> to diagnosis.> > Regards Bob Gore>

[Guest guest]

Hi Bob,

You're absolutely right. As we don't know what is normal for us before we fall

ill there is no way of telling where in the 'normal 'range we should be except

by trial and error. Personally I feel fine with low normal T4 above range T3

and undetectable TSH on an amount of thyroid meds that would probably send most

folk into a heart attack!

I think that the best exemplar of how the ranges

work is the graph on Australian hypo site. I will try to cut'n'paste, but it

doesn't always work!!

....

The

results for women are shown in the chart. The results for men were only

slightly different

..

:

..

One point that came out in my researches during the

hospital period

was that the Normal ranges are statistical normal

distribution curves

based on samples. Now clearly one fit person can have

a normal T4

reading of 17 while another has one of 11. Both are

within the

reference range and hence normal. If the first has a

reading of 10 [

just inside the reference values ]when ill that person

may be equally

as ill as the second person with a reading of 4 which

is well outside

the reference values. I've not been able to find any

references to

this in my researches and it seems to be a vital point

when it comes

to diagnosis.

Regards Bob Gore

Messages are not a substitute for professional medical

advice. Always consult with a suitably qualified practitioner before changing

medication.

[Guest guest]

I think this is the graph you mean . This says it all.

A study of the TSH of 65,000 people in 2000, 4 that further backs up the case for a reduction of the reference range, forms the basis of a very illuminating article on ‘Normal TSH’ from Thyroid Australia. The TSH graph within this article, reprinted below, has encouraged many medical practitioners to be more flexible in their interpretation of TSH results. Read the full article.

Hi Bob,

You're absolutely right. As we don't know what is normal for us before we fall ill there is no way of telling where in the 'normal 'range we should be except by trial and error. Personally I feel fine with low normal T4 above range T3 and undetectable TSH on an amount of thyroid meds that would probably send most folk into a heart attack!

I think that the best exemplar of how the ranges work is the graph on Australian hypo site. I will try to cut'n'paste, but it doesn't always work!!

....

The results for women are shown in the chart. The results for men were only slightly different

..

:

..

One point that came out in my researches during the hospital period

was that the Normal ranges are statistical normal distribution curves

based on samples. Now clearly one fit person can have a normal T4

reading of 17 while another has one of 11. Both are within the

reference range and hence normal. If the first has a reading of 10 [

just inside the reference values ]when ill that person may be equally

as ill as the second person with a reading of 4 which is well outside

the reference values. I've not been able to find any references to

this in my researches and it seems to be a vital point when it comes

to diagnosis.

Regards Bob Gore

Messages are not a substitute for professional medical advice. Always consult with a suitably qualified practitioner before changing medication.

[Guest guest]

For me it cannot find the website www.thyroid.org.au so I think perhaps it has been down for a while, try again in the morning Gill, maybe it will be up and running again.

Luv nne

I would be really grateful if someone can help - I really want to read this and I cant access the website! If its just me would someone email it to me please or upload it onto the files?

thanks in anticipation,

Gill

[Guest guest]

I would be really grateful if someone can help - I really want to read this and I cant access the website! If its just me would someone email it to me please or upload it onto the files?

thanks in anticipation,

Gill

I think this is the graph you mean . This says it all.

A study of the TSH of 65,000 people in 2000, 4 that further backs up the case for a reduction of the reference range, forms the basis of a very illuminating article on ‘Normal TSH’ from Thyroid Australia. The TSH graph within this article, reprinted below, has encouraged many medical practitioners to be more

Recent Activity

33

New Members

4

New Photos

1

New FilesVisit Your Group

Health

Fit for Life

Getting fit is now

easier than ever.

Drive Traffic

Sponsored Search

can help increase

your site traffic.

Women of Curves

on

A positive group

to discuss Curves.

..

[Guest guest]

Hi nne, thanks so much for checking, that's the message Im getting, so will try again. Off to bed now, got an early start!!

Gill x

[Guest guest]

HI Gill

Here is what I sent to all endocrinologists in 2005 - I think this is the information you are looking for.

Luv - Sheila

_____________________________________

25th November 2005

NHS endocrinologists and general practitioners

Dear Doctor,

RE: Thyroid Function Tests Guidelines

I would like to draw your attention to the first consultation draft of the proposed ‘UK Guidelines for the Use of Thyroid Function Tests’. The draft is now available to read and/or download at http://www.british-thyroid-association.org/news.htm and comments on this are invited by 23rd December 2005.

TPA-UK is at a loss to understand why BTA are recommending doubling the upper level of the TSH test to 10mU/L when the American Academy of Clinical Endocrinologists (AACE), the nation's largest organization of thyroid specialists, has taken the opposite view and confirmed that hypothyroidism, like many other illnesses that affect predominantly women, has been vastly under diagnosed. After a meeting by the AACE, the normal range for thyroid tests was dramatically narrowed, as noted in the AACE press release of January 2003: 1

“Until November 2002, doctors had relied on a normal TSH level ranging from 0.5 to 5.0 to diagnose and treat patients with a thyroid disorder who tested outside the boundaries of that range. Now AACE encourages doctors to consider treatment for patients who test outside the boundaries of a narrower margin based on a target TSH level of 0.3 to 3.0. AACE believes the new range will result in proper diagnosis for millions of Americans who suffer from a mild thyroid disorder, but have gone untreated until now.”

"The prevalence of undiagnosed thyroid disease in the United States is shockingly high - particularly since it is a condition that is easy to diagnose and treat," said Hossein Gharib, MD, FACE, and president of AACE. "The new TSH range from the AACE guidelines gives physicians the information they need to diagnose mild thyroid disease before it can lead to more serious effects on a patient's health - such as elevated cholesterol, heart disease, osteoporosis, infertility, and depression."

This new improved range increased the number of Americans with Thyroid illness from 13 million to approximately 27 million. Unfortunately, over 13 million Americans with thyroid disease remain undiagnosed, and the majority of those receiving treatment are not receiving appropriate levels of medication. Many doctors do not realise that they have not been adequately trained in the proper diagnosis and/or treatment of hypothyroidism, and the subsequent cost in human life and devastating illness is enormous. What makes this especially tragic is how easy treatment and recovery could be if doctors were given the correct information.

Unfortunately this misinformation also extends to our own country, as many of us have found to our cost. We also have a large number of doctors who are not adhering to, or are unaware of, even our own current guidelines. (See below.) Many merely ensure that blood levels are returned to within the reference range (often barely so) with no regard as to what is optimal for their patient. If this is then compounded by extending the reference ranges, as the BTA are suggesting, rather than shortening them, then many of us will either be condemned to a very poor quality existence, with a good likelihood of a reduced life expectancy, or forced to seek alternative means of treatment. This could include the private sector or even self-medicating, neither of which is particularly desirable from either the patients’ or their GPs’ point of view.

An article in the BMJ in August 1996 2 on the management of hypothyroidism and hyperthyroidism states: “The correct dose is that which restores the euthyroid state and relieves symptoms. In most patients these will be achieved by a dose of thyroxine resulting in a normal or slightly raised serum thyroxine concentration, a normal serum triiodothyronine concentration and a normal or below normal serum thyroid stimulating hormone concentration”.

This is backed up by a representative of the Department of Health 3 who, as recently as 23 rd November 2005, stated that: “It is currently considered good medical practice to rely upon clinical history and examination, in addition to blood tests, in the diagnosis of hypothyroidism”.

A study of the TSH of 65,000 people in 2000, 4 that further backs up the case for a reduction of the reference range, forms the basis of a very illuminating article on ‘Normal TSH’ from Thyroid Australia. The TSH graph within this article, reprinted below, has encouraged many medical practitioners to be more flexible in their interpretation of TSH results. Read the full article.

A new research study just released on 18 th November 2005 from the Cardiovascular Research Institute-South Dakota Health Research Foundation and The University of South Dakota School of Medicine 5 shows a link between low thyroid function and heart problems. “We provided strong evidence that low thyroid function alone induced in rats eventually can cause heart failure,” said Dr. A Gerdes, director of the Cardiovascular Research Institute and co-author of the study. “We also discovered that low thyroid function severely impaired cardiac blood flow due to a dramatic loss of the heart’s small blood vessels (arterioles). Within six weeks after inducing low thyroid function in rats, half of the hearts’ small arterioles were gone.” This study in rats is giving researchers hope that more aggressive treatment of hypothyroidism and borderline hypothyroidism will result in a reduction of heart disease in human beings. While further research is needed, these results suggest that low thyroid function has the potential to cause heart failure.

Yet another study in 2005 entitled ‘ The Evidence for a Narrower Thyrotropin Reference Range Is Compelling’ 6 came to the conclusion: “I t has become clear that previously accepted reference ranges are no longer valid as a result of both the development of more highly sensitive TSH assays and the appreciation that reference populations previously considered normal were contaminated with individuals with various degrees of thyroid dysfunction that served to increase mean TSH levels for the group.” They further stated that: “Importantly, data indicating that African-Americans with very low incidence of Hashimoto thyroiditis have a mean TSH level of 1.18 mU/liter strongly suggest that this value is the true normal mean for a normal population.Recognition and establishment of a more precise and true normal range for TSH have important implications for both screening and treatment of thyroid disease in general and subclinical thyroid disease in particular.”

T PA-UK questions the reliance on diagnosing by TFT’s alone. There have been many changes in thyroid tests over the years. Tests should be used as part of a clinical picture and not form the sole criteria for diagnosis

Each of these tests was hailed as the definitive test at the time but was found to be imperfect. (1) The metabolic rate was measured while the patient ran on a treadmill. (2) The next new test measured protein-bound iodide (PBI). (3) The T4-level thyroid test was then developed. (4) The T7-level test was devised, and then (5) the thyroid-stimulating hormone (TSH) test came along. Modern medicine is now into the fourth generation of TSH tests, and with each new test, doctors have noted that they have missed many patients with under active thyroid. It is very obvious that the current method of testing still misses many patients with under active thyroids. Therefore, doctors must treat the patient, NOT the blood test.”

TPA-UK is asking all doctors to take note of these recommended new guidelines, which, if implemented, would have a devastating effect upon the lives of the many thousands within the population who are suffering from hypothyroidism, and who would remain undiagnosed and/or under-treated as a consequence.

Yours sincerely

Sheila Thyroid Patient Advocate

References :

AACE 2003 Campaign Encourages Awareness of Mild Thyroid Failure, Importance of Routine Testing. http://www.aace.com/pub/tam2003/press.php Consensus statement for good practice and audit measures in the management of hypothyroidism and hyperthyroidism (BMJ 1996;313:539-544, 31 August).http://bmj.bmjjournals.com/cgi/content/full/313/7056/539 Matt Bolton, Customer Service Centre, Department of Health. Ref. Ref:DE00049269. T Bjøro et al, 'Prevalence of thyroid disease, thyroid dysfunction and thyroid peroxidase antibodies in a large, unselected population. The Health Study of Nord-Trøndelag (HUNT).' European Journal of Endocrinology 2000 143 639-647. http://www.eje.org/eje/143/eje1430639.htm Yi-Da Tang et al, ‘Low Thyroid Function Leads to Cardiac Atrophy with Chamber Dilation, Impaired Myocardial Blood Flow, Loss of Arterioles, and Severe Systolic Dysfunction.’ This Cardiovascular Research Institute (CRI) study is published in the Nov. 15 issue of Circulation, the journal of the American Heart Association. The study can be viewed online at: http://circ.ahajournals.org/. The news article is at: http://www.newswise.com/articles/view/516245/ Leonard Wartofsky and A Dickey, The Evidence for a Narrower Thyrotropin Reference Range Is Compelling’ The Journal of Clinical Endocrinology & Metabolism Vol. 90, No. 9 5483-5488 http://jcem.endojournals.org/cgi/content/abstract/90/9/5483

Re: Normal Values of T4 etc.

I would be really grateful if someone can help - I really want to read this and I cant access the website! If its just me would someone email it to me please or upload it onto the files?

thanks in anticipation,

Gill

I think this is the graph you mean . This says it all.

A study of the TSH of 65,000 people in 2000, 4 that further backs up the case for a reduction of the reference range, forms the basis of a very illuminating article on ‘Normal TSH’ from Thyroid Australia. The TSH graph within this article, reprinted below, has encouraged many medical practitioners to be more

Recent Activity

33

New Members

4

New Photos

1

New FilesVisit Your Group

Health

Fit for Life

Getting fit is now

easier than ever.

Drive Traffic

Sponsored Search

can help increase

your site traffic.

Women of Curves

on

A positive group

to discuss Curves.

..

No virus found in this incoming message.Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.2/1224 - Release Date: 14/01/2008 17:39

[Guest guest]

Hi,

     I’ll repeat it, you may not have been able to get through as

my original email was in HTML to make sure the graph was displayed- hopefully

this will be what you want. It starts with a snip for an earlier email.

                                       

> I meant that

this might be an opportunity to question endocrinologists

> about the

reliability of diagnosing and treating ONLY by blood tests

> results and

not looking at the fuller clinical features, questioning

> them about

the need for Free T3 testing and understanding  TSH

> results.

That was exactly

my point.

I was doing some

digging this morning and found some tables for

biological

variation in test analytes (from an extremely reputable

source). This

gives the range (to one standard deviation) of

variation within

an individual and between individuals. Here's the

figures:

      

intra-individual     inter-individual

TSH     

19.3%                 19.7%

FT4      

7.6%                 12.2%

FT3      

7.9%               no figures available

I also found an

interesting paper that suggests that there are large

seasonal

variations in TSH and FT3 hormone levels (higher in winter

to keep you warm,

lower in summer which makes sense) with variations

being up to a

third of the reference range!

Added to this, I

also spoke to the body responsible for co-ordinating

standards of lab

testing in Wales. They tell me that the targets for

test accuracy are

+/- 10%.

If you take both

of these factors into account, the potential error

is moderately

large. That's fine, so long as the person doing the

interpretation is

aware of it. But a doctor who just looks at a

result and a

reference range and assumes that in-range means well is

missing a lot of

subtlety - particularly if that is the only

diagnostic tool

used (i.e. no clinical signs/symptoms considered).

Anyway, I'm off

to meet my endocrinologist in a few minutes, so I'll

see whether these

arguments wash with him. Let's hope I don't leave

his office in a

straight-jacket!

Australia

TSH 0.3 - 5.0, T4 11 - 23, T3 3.5 - 6.7 (www.thyroid.org.au)

Canada

TSH 0.3 - 4.0, T4 12 - 21, no T3 found (www.cs.ubc.ca)

New

Zealand TSH 0.3 - 5.0, T4 12 -25, no T3 (from my aunt!)

Saudi

Arabia TSH 0.2 - 5.0, T4 10.0 - 25.0, no T3

Got this

information from the major Canadian bloodtest lab. http://www.mdsdx.com/MDS_Metro_Laboratories/Health_Care/Reference.asp

TSH 0.38

- 5.5 mU/L

T4

(age 21 - 60) 90-200 (age 60) 65--180 nmol/L

-- this range narrows with increasing years.

Free T3

3.5 - 6.5 pmol/L

Free T4

10.5 - 20.0 mU/L

This

link doesn't even list a T3 test any more. The lab. favours FT3 and they

won't do both.

(not

sure where the people at UBC got their lab ranges from but plan to follow up on

this one day).

Hope

this does not muddy the waters.

M

----- Original

‘Normal’

TSH

ALUN

STEVENS MSc FIAA

THIS IS AN EXTRACT OF

THE ARTICLE. THE FULL ARTICLE IS AVAILABLE TO MEMBERS OF THYROID AUSTRALIA ONLY. FOR

INFORMATION ON HOW TO JOIN THYROID AUSTRALIA CLICK HERE TO

VISIT THYROID AUSTRALIA HOME

Click on " ABOUT

US "

The most

common questions that Thyroid Australia is asked involve the interpretation of

Thyroid Function Tests (TFT’s). Many people have been told that their TFT

results are ‘normal’. So what is ‘normal’? In this

article we will focus on the test for Thyroid Stimulating Hormone (TSH) which

is the most common test ordered.

The

‘normal’ Reference Range for the test is intended to

represent the range of values which can be expected in the healthy population

– ie those without any thyroid ailment. The Reference Range is found by

taking a sample population of healthy individuals and determining their TSH

levels. The lowest and highest 2.5% of readings are excluded so that the Reference

Range covers 95% of the healthy population. There are a number of different

tests for TSH with different levels of sensitivity. They each have their own Reference

Range. The most common tests generally have lower limits to their Reference Ranges

around 0.2 to 0.5 mIU/L and upper limits from 3.5 to 5.0 mIU/L.

A recent

study in Norway provides a good example of the use of the TSH

test in practice.1

....

The

results for women are shown in the chart. The results for men were only

slightly different

..

:

....

The

features of this result are:

The distribution of TSH readings in the healthy

population is skew. It is not the common bell shaped curve centred in the

middle of the reference range.

The most common value, or Mode, is at 1.25.

....

....

The

conclusions which can be drawn from this survey are:

TSH results in the upper half of the Reference Range

have a low probability of being ‘normal’. This does not mean

that they are not ‘normal’. It means that they are unlikely to

be ‘normal’.

....

....

Another

important point which needs to be borne in mind when interpreting statistics

like these is that it is the population which has a range of values with

probabilities for each reading. Each healthy individual is only at one of the

points. They are ‘normal’ when they are at that point. For those on

thyroxine replacement, being in the Reference Range is not good

enough in itself. You need to be at your own set point. This will probably be

near the lower end of the Reference Range.

This

analysis of the distribution of TSH readings in the healthy population supports

our recommendations to thyroid patients:

....

....

Do not accept that a Thyroid Function Test is

'normal' just because the result is within the Reference Range if

you are still feeling unwell.

References

1.

T Bjøro et al, 'Prevalence of thyroid disease,

thyroid dysfunction and thyroid peroxidase antibodies in a large, unselected

population. The Health Study of Nord-Trøndelag (HUNT).' European Journal of Endocrinology 2000 143 639-647. Download here.

2.

J Stockigt, 'Subclinical Hypothyroidism or Mild

Thyroid Failure: How important is early diagnosis and what treatment is

optimal?' Interview With Sigma Pharmaceutical 2001 http://www.thyroid.org.au/Information/Stockigthtml.

Accessed 30 December 2001.

Alun

s is an actuary with his own consultancy. He is also Secretary of Thyroid

Australia

This article is published in our newsletter Thyroid

Flyer Volume 3 Number 1 January 2002.

This article can be reproduced provided it is

reproduced in full, acknowledges the source and is not sold for profit.

© Copyright 2001, Thyroid Australia Limited ABN 71 094 832 023

333 Waverley Road, Mount Waverley, 3149, Australia

Thyroid Australia Home-www.thyroid.org.au

Re:

Normal Values of T4 etc.

I would be really grateful if

someone can help - I really want to read this and I cant access the

website! If its just me would someone email it to me please or upload it

onto the files?

thanks in anticipation,

Gill

I think this is the graph

you mean . This says it all.

A study of the TSH of

65,000 people in 2000, 4 that further backs up the case for a reduction of the

reference range, forms the basis of a very illuminating article on

‘Normal TSH’ from Thyroid Australia. The TSH graph within this

article, reprinted below, has encouraged many medical practitioners to be more

Recent Activity

·

33

New

Members

·

4

New

Photos

·

1

New

Files

Visit

Your Group

Health

Fit

for Life

Getting fit is now

easier than ever.

Drive Traffic

Sponsored

Search

can help increase

your site traffic.

Women of Curves

on

A positive group

to discuss Curves.

..