Hypothyroid, Strenuous Exercise & AFib - Thyroid UK

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Hypothyroid, Strenuous Exercise & AFib

Barny12 profile image
9 Replies

Hi all,

To keep a long story short, I'm pretty sure I developed subclinical hypothyroidism a couple of years ago. I was exercising fairly hard during this period (with fell running) and was feeling more and more tired than usual but pressed on with training anyway. Ended up having pretty bad attack of arrythmia while in the hills and was finally diagnosed with atrial fibrillation last December. I suspect that overexercising was the culprit, but my cardiologist doesn't think the underactive thyroid had anything to do with it.

Does anyone have any info on strenuous exercise while hypo causing heart problems? Thanks.

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9 Replies
Hennerton profile image
Hennerton

It makes me want to weep that a cardiologist would not realize that low thyroid levels would compromise the working of the heart. I cannot point you in the direction of any studies but I am sure someone will and in the meantime, perhaps you could post your actual thyroid blood test results at that time. I assume your cardiologist checked these?

Barny12 profile image
Barny12 in reply toHennerton

Hah! The cardiologist didn't even ask about my thyroid until I mentioned possibly being hypo and even then didn't enquire as to my blood test results. I'll post my bloods in my reply to SlowDragon. Thanks.

SlowDragon profile image
SlowDragonAdministrator

First step is to get FULL Thyroid and vitamin testing

Low FT3 is extremely common when under medicated

How much Levothyroxine are you currently taking?

How long at that dose

Do you always get same brand of Levothyroxine

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

Is this how you do your tests?

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies or all vitamins

thyroiduk.org.uk/tuk/testin...

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random

If antibodies are high this is Hashimoto's, (also known by medics here in UK more commonly as autoimmune thyroid disease).

About 90% of all primary hypothyroidism in Uk is due to Hashimoto's.

Have you had thyroid antibodies tested already?

Or vitamins?

Low FT3 can affect the heart

Marz has link to book on heart and its close links to thyroid hormones

Come back with new post once you get full Thyroid and vitamin results

Barny12 profile image
Barny12 in reply toSlowDragon

Thanks for the reply. I didn't get the full bloods done at the time, just the basic NHS one. (TSH 5.92, T4 10.60 I was just hoping for some idea of how realistic a concept it might be that strenuous exercise while hypo may cause heart problems. Thanks.

SlowDragon profile image
SlowDragonAdministrator in reply toBarny12

If you were on Levothyroxine.......That shows you were EXTREMELY under medicated

On Levothyroxine TSH should be under 2, and many/most patients need TSH significantly under one

Most important results is FT3....needs to be at least half way in range

FT4 should be at least in top third of range

What's the range on FT4? 10.6 is likely very low within range

FT3 is a goldilocks hormone - we need the right amount....not too much...or too little

ncbi.nlm.nih.gov/pubmed/175...

Barny12 profile image
Barny12 in reply toSlowDragon

Those readings were from bloods taken when I was being checked for afib. I self diagnosed that as I was vegan I was likely to be iodine deficient so began an iodine supplement from the Vegan Society. My following 3 monthly readings were TSH 2.82 T4 10.8, then TSH 2.32 T4 9.10, then TSH 2.775 T4 9.90.

My GP advised no further treatment for thyroid issues, so my main focus has been the atrial fibrillation.

SlowDragon profile image
SlowDragonAdministrator in reply toBarny12

you need to test vitamin D, folate, ferritin and B12

These are frequently too low with any thyroid issues

But obviously if vegan, low B12 is inevitable unless you have been supplementing

If thyroid antibodies are high, due to autoimmune thyroid disease (Hashimoto's) low vitamin levels are extremely common

Iodine is extremely controversial and can make Hashimoto's worse

drknews.com/iodine-and-hash...

thyroidpharmacist.com/artic...

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

If/when also on T3, make sure to take last dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test

Is this how you do your tests?

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies or all vitamins

thyroiduk.org.uk/tuk/testin...

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random

Batty1 profile image
Batty1 in reply toSlowDragon

Slowdragon....is AFIB the same or simular as Angina attacks?

Aurealis profile image
Aurealis

Thyroid hormones that are too high, or too low can cause AFib. Cardiologists are supposed to investigate possible reversible causes of AFib first- haha. (See NICE guidance) AFib can also be triggered by exercise if you are prone to it.

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