The introduction is also posted on Spotify as a podcast by “Gerry at The Health Equation”

You can search Spotify for “Gerry at The Health Equation”

Or use the link below

https://podcasters.spotify.com/pod/show/gerrygaj

Below is the specific link

Gerry Gajadharsingh writes:

“A recent article, of an interview on Medscape was obviously based in America due to the opening paragraph which stated:

If you’re like most primary care clinicians, your email inbox is flooded with messages from patients with questions about lab results.

For many years trying to get hold of patient blood test results from the NHS was like trying to get blood out of a stone. This has recently changed with many patients able to access their blood test results via the NHS App or NHS practices indeed accepting request from private clinicians such as myself to share results (although trying to get results out of an NHS hospitals is still incredibly difficult even for NHS GP practices).

It is still common for NHS patients to be told that all their blood test results are normal and patients usually don’t get to see the results. From what I have seen, I believe that many clinicians simply focus on if there is evidence of significant pathology needing further investigation, otherwise the answer is usually everything is normal. So, patients usually have a very limited understanding of which blood parameters have actually been tested and what normal actually means, understandably if their symptoms continue, despite so-called normal blood results, they still need to know the cause or mechanism behind their symptoms.

Whenever I organise tests in the private sector, I receive results in a very timely fashion, review the results send the patient the actual results from the lab or imaging centre (usually within 48 hours of the test or imaging being done) and also a follow-up email explaining the findings and its applications for their management which of course can be expanded upon during a follow-up consultation. I cannot stress enough that having any test, whether it’s imaging or laboratory testing, can cause significant raised anxiety for many patients, whilst they are waiting for the results. It goes without saying that I think it is good practice that if you’re organising any type of investigation, the results are received by the patient as soon as possible.

Conventional medicine tends to focus on so-called normal laboratory reference ranges but there is increasing use of what we call functional ranges, which tend to be the higher end or lower end of normal reference ranges, which can sometimes be clinically relevant to the patient’s management.

Thyroid function tests are very common blood tests. We usually include TSH and FT4 as a first line test and then depending on the results, sometimes FT3, thyroid antibodies and TSH receptor antibodies

Br far the most common first line test is TSH (Thyroid Stimulating Hormone). This measures the thyroid status in a way that integrates more information about the long-term thyroid status and not small changes in thyroid hormone levels. TSH is made by the pituitary gland in the brain, which integrates information about the signals of high and low levels from each of the different thyroid hormones. As the name suggest TSH stimulates the thyroid to make more thyroid hormones.

If TSH is low, perhaps there’s a little bit of extra thyroid hormone in the body. It can be either temporary or more chronic, but that higher amount of thyroid hormone is telling the pituitary gland in the brain to start making less. So TSH levels go low when we need less thyroid hormone.

One of the most common situations for a temporarily low TSH level is what we call nonthyroidal illness, like a common cold or just being under the weather. Other things that can artifactually lower the TSH level could be the use of steroids, such as prednisolone for asthma or some sort of a rheumatologic condition. Also, the TSH level could be low if a person has been recently exposed to very high amounts of iodine, such as iodinated contrast needed for a CT scan. GLP1 agonists (such as Ozempic) can also cause low TSH.

If the TSH level remains persistently low, usually in the presence of high thyroid hormone (FT3 and/or FT4) levels, the most common reason for hyperthyroidism is Graves’ disease in which there are autoantibodies — measurable in the blood — that can stimulate the thyroid gland in the neck to make extra thyroid hormone.

Conversely, if TSH is High, perhaps there is not enough thyroid hormone in the body which again can be temporary or more chronic, but that lower amount of thyroid hormone is telling the pituitary gland in the brain to start making more.

We need at least two tests to confirm a high TSH level. A persistently elevated TSH level is a signal there might be low thyroid hormone levels in the body, which could be transient or more longer lasting.

If the TSH level is confirmed high and the thyroid hormone levels are low, the most common cause of hypothyroidism in Western Countries is Hashimoto thyroiditis.

Globally, iodine deficiency is the most common reason for hypothyroidism and may be a problem in parts of the globe where there are endemically low iodine levels in soil, crops, and the food supply like not having enough iodized salt. The thyroid is reliant on having enough iodine as a micronutrient to make thyroid hormone. If it doesn’t, the thyroid really can’t make thyroid hormone. It’s important to also remember, though, that having too much iodine can result in hypo- or hyperthyroidism.

We can test for iodine levels in the blood.

T4 or thyroxine, the inactive form of thyroid hormone, is made by the thyroid gland in the neck and the main substrate is the amino acid thyrosine (protein) with numerous enzymes and cofactors, including B vitamins and magnesium.

T4 is then converted into T3 triiodothyronine mostly in the liver, which is the so-called active form of thyroid hormone, selenium is an important cofactor in this conversion.

By far the more common clinical presentation is of hypothyroidism, the mainstay in medical practice is thyroid replacement treatment with synthetic thyroid usually levothyroxine. The current protocol in the UK is to treat if TSH >10. It used to be the case that once the patient was commenced on thyroid replacement, they would generally need it for the rest of their life. This view is increasingly being challenged by clinicians and patients.

Outside of this criterion it’s not uncommon to support patients with low functioning thyroid with a variety of functional interventions including specific nutritional supplementation.

Hormones are complex and there is a tendency for them to interact with each other and this is especially true of thyroid and adrenal hormones, which I have previously blogged about.”

https://www.thehealthequation.co.uk/is-adrenal-fatigue-a-real-condition/

Medscape

Ann Thomas, MD, MPH

If you’re like most primary care clinicians, your email inbox is flooded with messages from patients with questions about lab results. A common query: Should I be worried about an abnormal value on a test of thyroid-stimulating hormone (TSH)?

For guidance, Medscape Medical News spoke with Angela Leung, MD, an associate professor of medicine in the Division of Endocrinology, Diabetes & Metabolism at the UCLA David Geffen School of Medicine and an endocrinologist at UCLA and the VA Greater Los Angeles Healthcare System, and Karen Tsai, MD, an assistant clinical professor of endocrinology at City of Hope Comprehensive Cancer Center in Duarte, California. The following interview has been edited for length and clarity.

Medscape: Why do you usually start by measuring TSH levels?

Leung: We need to measure the thyroid status in a way that integrates more information about the long-term thyroid status and not small changes in thyroid hormone levels. TSH is made by the pituitary gland in the brain, which integrates information about the signals of high and low levels from each of the different thyroid hormones.

Now we can measure the actual thyroid hormones — primarily we’re talking about T3 and T4 — but if we do that, we are relying on a single snapshot in the bloodstream at that moment. The levels might change throughout the day in response to ongoing metabolism and outside stresses. So, we usually start by measuring the TSH level, which is a good representation of the compilation of all those things over the past 30 days or so.

Medscape: How do you describe a low TSH result to patients?

Leung: Whenever we encounter a low TSH level, we want to repeat the test because it is a dynamic test, and it can change in response to several factors. If it is indeed low, we’re thinking that perhaps there’s a little bit of extra thyroid hormone in the body. It can be either temporary or more chronic, but that higher amount of thyroid hormone is telling the pituitary gland in the brain to start making less. So TSH levels go low when we need less thyroid hormone.

 Medscape: What are some of the reasons for a low TSH level?

Leung: One of the most common situations for a temporarily low TSH level I see is what we call nonthyroidal illness, like a common cold or just being under the weather. Other things that can artifactually lower the TSH level could be the use of steroids, such as prednisone for asthma or some sort of a rheumatologic condition. Also, the TSH level could be low if a person has been recently exposed to very high amounts of iodine, such as iodinated contrast needed for a CT scan.

If the TSH level remains persistently low, usually in the presence of high thyroid hormone (T3 and/or T4) levels, the most common reason for hyperthyroidism is Graves’ disease in which there are autoantibodies — measurable in the blood — that can stimulate the thyroid gland in the neck to make extra thyroid hormone.

Medscape: And what does an elevated TSH level mean?

Leung: Again, we want to confirm that it is elevated. We need at least two tests to confirm a high TSH level. A persistently elevated TSH level is a signal there might be low thyroid hormone levels in the body, which could be transient or more longer lasting.

Medscape: What are some of the most common causes of an elevated TSH level?

Leung: If the TSH level is confirmed high and the thyroid hormone levels are low, the most common cause of hypothyroidism here in the United States is Hashimoto thyroiditis.

Globally, iodine deficiency is the most common reason for hypothyroidism and may be a problem in parts of the globe where there are endemically low iodine levels in soil, crops, and the food supply like not having enough iodized salt. The thyroid is reliant on having enough iodine as a micronutrient to make thyroid hormone. If it doesn’t, the thyroid really can’t make thyroid hormone. It’s important to also remember, though, that having too much iodine can result in hypo- or hyperthyroidism.

Tsai: I take a glance at their medication list. Some of the patients are on methimazole or levothyroxine, and those medications should be adjusted first to normalize the TSH level. Other medications like lithium and amiodarone can also cause elevated TSH levels. We are also seeing a lot of patients on cancer therapies, such as tyrosine kinase inhibitors or immunotherapy, that can cause an elevated TSH level.

Medscape: If the repeat TSH test shows that TSH levels are still elevated, what comes next in your workup?

Tsai: If there’s not a real clear-cut diagnosis, I’ll order the thyroid peroxidase antibody and the thyroglobulin antibody, although thyroid peroxidase antibody, which is indicative of autoimmune thyroid disease, alone is usually sufficient to make that diagnosis.

Medscape: Should clinicians follow thyroid antibodies over time?

Tsai: I usually don’t repeat the antibody tests. In those circumstances where patients who were diagnosed 50-60 years ago and perhaps it is unknown if they had the thyroid antibodies measured at the time and now, they’re saying, “Do I actually have Hashimoto’s?” or “Do I really need to continue this for the rest of my life?” I do repeat antibody tests to help gauge if the patient’s levothyroxine can be stopped.

Medscape: How important is it to follow T4 or T3 levels?

Tsai: T4 and T3 levels can help differentiate overt thyroid dysfunction — where T3 and/or T4 levels will be abnormal — from subclinical thyroid dysfunction — where T3 and T4 levels would be normal. In general, although we do not fully appreciate the best metric to monitor hypo- or hyperthyroidism, because some patients with a normal TSH level still may have symptoms of thyroid dysfunction, these peripheral thyroid hormone levels are usually the most helpful at the time of initial diagnosis.

Medscape: What are your criteria for initiating treatment for hypothyroidism?

Tsai: If the TSH level >10 mIU/L, I recommend levothyroxine hormone replacement. A lot of published data support clinical benefit in this group.

There is a grey area in those patients who have a TSH level higher than the upper limit of the reference range but less than 10. If the patient doesn’t have overt hypothyroid symptoms, I discuss the findings with the patient but don’t really feel eager to treat. I recommend checking the levels again in 6 months to see where that TSH goes, and if it worsens or becomes greater than 10 mIU/L, I then recommend levothyroxine hormone replacement.

It is also important to note that a TSH level of 5-7 may be an acceptable range for older patients, and they do not require levothyroxine.

The other category is patients whose TSH level is greater than the upper limit of the normal reference range but less than 10 and with overt hypothyroid symptoms such as fatigue, unintentional weight gain, constipation, or cold intolerance. In these patients, it is worthwhile to try a low dose of levothyroxine (25-50 mcg/d) and repeat TSH and free T4 tests in 6-8 weeks and see if the TSH level normalizes.

Leung: When you look at subclinical hypothyroidism, the situation of an isolated high TSH level in the setting of normal T4 levels, if the TSH level is mildly elevated in the 5-7 mIU/L range, there’s a 60% chance that it will normalise within six months.

Going back to Karen’s point, a lot of people are started and maintained on low doses of thyroid hormone forever and ever. A recent study on levothyroxine use found half of the prescriptions were unnecessary.

Medscape: In an era where many patients obtain much of their health information from TikTok, what’s your approach with patients with a normal TSH level who feel that they should have more testing or start treatment?

Tsai: Fatigue is one of the common referrals we get into our endocrinology practice, and everyone is convinced that their thyroid is the culprit. It is important to note, however, that fatigue can be due to different diseases such as anaemia, depression, sleep disorders, or a recent viral illness.

TSH tests are readily available and cheap. I don’t mind ordering the lab test again if it helps give the patient some reassurance. I also find that patients are relieved once they hear from their endocrinologist that their thyroid is unlikely to be the cause of their fatigue.

Some other endocrine causes we may consider additionally working up include adrenal insufficiency, vitamin D deficiency, and diabetes. A comprehensive metabolic panel and complete blood count is part of my workup to rule out any gross electrolyte abnormalities or any new diagnosis of anaemia, liver disease, or chronic kidney disease.

Medscape: What are your criteria for recommending that someone see an endocrinologist?

Tsai: Our primary care colleagues can do a workup and interpretation of thyroid function tests in most cases. In the situations where the thyroid function test results are discordant (i.e., elevated TSH and elevated free T4 levels or low TSH and low free T4 levels) or difficult to interpret, it would be appropriate to refer the patient to an endocrinologist.

One of the common referrals that we do get from the community is a patient’s thyroid function tests going from hyperthyroid to hypothyroid without a clear explanation or the patient is sub optimally controlled with levothyroxine or methimazole. In those circumstances, it would be worthwhile to send to an endocrinologist try to discern an underlying cause or for optimization of medication.