Chasing 'Ideal' Lab Test Results is the Road to Nowhere

Chasing 'Ideal' Thyroid Lab Test Results is the Road to Nowhere

During the 1970s the shift to a lab-test-centric model with T4 medication was the start of conveyor-belt thyroid treatment. It was much easier and faster for the doctors treating thyroid patients. However, it leaves many patients under-medicated or improperly treated.

Both doctors and patients are now highly focused on lab test results. In many cases, both groups (patients and doctors) are operating under the mistaken belief that by focusing mostly on trying to achieve some 'ideal' lab test results, the patients will fully recover. 

This blog post points out the huge flaws in this approach.

Note the focus of this blog post is on lab testing during thyroid treatment.  Lab test results are extremely valuable during the diagnosis stage, prior to a patient being given any thyroid hormone - there is no question of this.

What Usually Happens During Thyroid Treatment 

Most doctors use the TSH test to assess their patients thyroid medication dosage. The standard thyroid medication is Levothyroxine/Synthroid/T4.
Some doctors also test Free T4 (FT4) and a few also test Free T3 (FT3). 

Most of these doctors are content that their patient is well-treated on T4 medication if the patient's TSH is in the reference range. Some prefer to see TSH low in the reference range. Most doctors get concerned if TSH is near zero. TSH has become the de facto way of assessing the T4 medication dosage. T4 has become the de facto treatment. 

As for patients, they too are interested in their thyroid lab test results. Some more well-informed patients are hoping for a high in the range FT3 result. Some seem to be trying to achieve some ratio of Free T3 to Reverse  T3 (FT3//rT3 ratio),  that is if they can get rT3 tested. Most of the well informed patients are still using T4 medication or natural desiccated thyroid medication (if they can get it).

Some History Prior to the 1970s

Synthetic T4 (Synthroid, Levothyroxine) was first introduced in the 1950s. Current thyroid lab tests (TSH, and the other thyroid labs) were invented in the 1970s.

Before these events, all doctors had available was good clinical judgement, based on the symptoms and signs (body temperature etc. and possibly basal metabolic rate), of the patient, and the option to use natural desiccated thyroid (NDT).

When doctors worked with a patient, they would assess many things and try to reach a judgement over whether the patient might have a thyroid problem or not. If low thyroid hormones were suspected, a trial of NDT would be started. If there were improvements in symptoms and signs, the NDT would be adjusted (titrated) to a higher or lower dose if needed. This titration process would continue based on the presenting symptoms and signs of the patient. This meant that the doctor would have to work with the patient and listen to what they were saying about how they were feeling in response to treatment. There were no laboratory tests to get in the way between the doctor and the patient in front of them.

This approach worked pretty well a lot of the time. It ought to have moved forward from there, taking advantage of modern lab testing (but not being a slave to it), and having all the other thyroid medications available. 

What Happened from the 1970s Onwards

In the 1970s the TSH test became the standard way to assess whether thyroid treatment was working. Levothyroxine/Synthroid/T4 became the standard medication for treatment. Both of these required almost no effort on the part of the doctor or endocrinologist compared to what happened in the past. It vastly reduced the work of the physician. The reliance on the TSH test and the use of T4 medication also virtually guaranteed that no patient would ever be over-medicated. 

This sea-change was the beginning of conveyor-belt thyroid treatment, optimised for the doctor and far less likely to result in over-medication of the patient. It was much more likely to result in the under-medication of the patient!

Unfortunately, it is a method that usually results in improperly treated hypothyroidism. It is a broken paradigm.

Why is this a broken paradigm? I have written about this in many other blog posts, but here is a resume based on recent research:

  1. TSH can be totally suppressed when on thyroid treatment, i.e. near zero. This is fine and it does not mean the patient is hyperthyroid. So, keeping someone to an in-range TSH may leave them under-medicated.
  2. TSH does not track symptom improvement. So, a doctor cannot see a change in T4 medication and a lowering of TSH and assume that the patient is doing better.
  3. FT4 does not track symptom improvement either. A higher level of FT4 does not mean that the patient will be feeling better.
  4. FT3 does track symptom improvement but this is not the meaure that most doctors focus on.
  5. The reference ranges for FT4 and FT3 are population ranges - they are far too wide to conclude anything about whether a patient is well-treated or not.
  6. Real individual reference ranges (which cannot be known before treatment) are less than half as wide as the wide population ranges for FT4 and FT3.
  7. rT3 may or may not be an issue, and for sure there is no ideal FT3/rT3 ratio for all patients. Just as the lab ranges are wide population ranges, people all have their own individual requirements for their labs. No ratio or reference range can be applied to all people. Very high rT3 is usually an issue but that's about all you can say about it in isolation - symptoms and signs of the patient say more.
  8. T4 does not work for all patients. Some patients cannot get well using T4 medication.
  9. Research has shown that the loss of conversion capability and of the thyroid gland in thyroidectomy patients, causes the loss of the abiity to achieve a balance of thyroid hormones and good conversion rate (homeostatic balance).
  10. We also know that the thyroid gland itself is responsible for around 25% of our T3, mostly through conversion, so tissue damage through Hashimoto's, or through removal of the thyroid, loses a huge amount of ability to convert from T4 to T3. This can often not be compensated for with T4 alone.
  11. We also know from research that some people have genetic defects that reduce the capability to convert from T4 to T3 (DIO1 and DIO2 gene defects).
  12. We also know from an immense body of thyroid patients that many of them need different medications to get well: T4, NDT, T4/T3, or in some cases T3-Only.

So, the current paradigm of thyroid treatment is broken, and the research has shown this.

The Consequences of the Broken Paradigm

This is the really sad aspect of all of this.

Thyroid patients are being left improperly treated in many cases. They are either on the wrong medication for them, or they are being left under-medicated.

Both doctors and thyroid patients are now incredibly focused on lab test results. This alone is liable to waste vast amounts of time, and not lead to a good treatment and outcome. Both thyroid patients and doctors are chasing some ideal set of laboratory test results. We know from the research that it is virtually impossible to use just the lab test results to determine if someone is either on the right medication or the correct dosage of it.

The shift to this broken paradigm of lab-test-focused treatment and T4 medication has caused generations of doctors and patients to become fixated with lab test results. It has caused both doctors and patients to believe that these test results will reveal something amazing. It is sad, because the lab test-focused approach will not work - the research has proven this.

What Ought to Happen

Lab test results should only be used in a supportive role during treatment.

You do need to have the lab test results, but watching how they change in relation to each other and to symptoms and signs is the most important thing.

The medical history of the patient,  and their presenting symptoms and signs should always be centre stage.

The focus should be improving how well the patient feels. Labs can give an indication if the treatment is working well. 

Examples to illustrate:

  1. If the dosage of natural desiccated thyroid was increased and the patient felt they had more energy, and FT3 also increased, and TSH lowered and FT4 raised a little, this would indicate that the NDT was being absorbed. It would also suggest that the treatment was resulting in higher FT3, which we know tracks symptoms, and that the patient was actually responding to. This process of adjustment could continue until the patient felt well. Even if TSH went to zero it is not a problem, as long as the patient does not feel hyperthyroid, and FT3 does not go over the top of the reference range (there may be exceptions to this. When the level of T3 medication gets higher I would argue that a little over the reference range is also ok).
  2. If someone was on T4 medication, or even NDT medication, and it was adjusted and FT3 was mid-range, FT4 was mid-range, and TSH only 2.0, some doctors would say that the patient was properly treated, even if they continued to have serious symptoms. What ought to occur is that the labs should not be used to determine if the medication is sufficient. The medication should be increased, even though the lab tests are in the middle of the range. On thyroid treatment, TSH can be suppressed, and many patients do better with high in the range FT3. But the main thing in this case, is that the patient does not feel adequately treated - they still have symptoms. In many cases T4 medication will not fix all the symptoms. A T4/T3 combination of some kind might be needed. In a small percentage of cases far more T3 may be needed.

The response to changes in treatment (the medication type or the dosage of it) should be paramount.

Treatment should be patient-centric not lab-test-centric once again. Just focusing on lab tests as the most signficant thing and looking for some mythical good level is not what doctors or patients should be doing.

Laboratory tests should be used only to assess how the labs are changing in response to treatment and they should not be used to state whether the treatment is adequate or not.

The clinical position - the SYMPTOMS and the SIGNS are the most important things, with the labs being subservient to these. 

The change in the way thyroid treatment is managed that occurred in the 1970s has been the biggest step backwards that we have ever seen with the treatment of this disease.

We need a change in both the way doctors think about thyroid treatment and the way the thyroid patients themselves think about thyroid treatment.

Doctors and thyroid patients are both too focused on chasing 'ideal' thyroid laboratory test results. This has been the road to nowhere for some time and it continues to lead there. 

The advent of thyroid lab tests for TSH, FT4 amd FT3 ought to have made thyroid treatment far better and easier. However, in the process of using them they have become the main focus and T4 medication has become the main treatment . This is where it has all gone wrong. 

Both groups of people (doctors and patients) have been mesmerised by what could be viewed as the 'biggest confidence trick' in the history of treating thyroid problems (a confidence trick that has been played on both patients and doctors).

I hope this was helpful. It was not intended to be depressing - simply eye opening.

The majority of the information within this blog post is also contained and expanded upon in my book, 'The Thyroid Patient's Manual'.

Best wishes,