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Avatar universal

Low FT3, high rT3

1985, weight after five babies = 96 lbs
1985, diagnosed "ankylosing spondylitis."  Took NSAIDS for 14 years (BTW, never had it).  Spent years freezing with constant fatigue.  Had slightly high calcium.
1994, diagnosed Hashimoto's (TSH = 78, "antibodies" = 685).  By time of diagnosis, I was up to 155 pounds.  Went on Synthroid but never felt well and have never lost weight.
1999, parathyroidectomy (bone loss, anxiety, hypertension (resolved)).  Spontaneously lost 12 lbs.

2002, Body for Life.  I followed the diet and exercise plan precisely but lost no weight.  I am not a food addict.  Other exercise and diet trials never result in any weight loss.

2002 - 2007:  I have tried many times to take Armour (or a little Armour + Synthroid) to get FT3 up a bit.  Each trial ends with an episode of swelling, low potassium, high BP, anxiety.  I have never OD'd on thyroid meds (TSH never below .8).  I always go back to Synthroid and never feel well.

Recently diagnosed Conn's Syndrome.  High BP, weakness, low K, etc., are responding to spironolactone but anxiety is still excessive.

CRP = 14.18 (0 – 3)

1/7/08 tests on 88.5 mcg
TSH = 1.913
FT3 = 2.7 (2.3 - 4.2)
FT4 = 1.5 (.61 - 1.76)

2/19/08 tests on 100 mcg (per doc)
TSI = 111 ( 0 - 129)
TPO Ab = <10 (0 - 34)
Tg Ab = <20 (0 - 40)
rT3 = 331 (90 - 350)

It appears I am converting to rT3 instead of to T3.  I have read several articles on Pubmed about the seriousness of cardiac events with low T3.  One article defines low FT3 as <3.1

I have gone off Synthroid for a few days and can feel the anxiety lifting a bit but know I'll soon start having hypo symptoms.

Is TSI high enough to be contributing to the anxiety?
Why am I converting to rT3 instead of to T3?
Does high rT3 contribute to anxiety?
What can be done?

Thank you,
Val
4 Responses
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Avatar universal
BTW, the research I've read on low T3 indicates that cardiac events are more serious with "low T3 syndrome," not that low T3 by itself causes cardiac events.

Pingitore A, et.al. Acute effects of triodothyronine replacement therapy in patients with chronic heart failure and low-T3 syndrome: a randomized, placebo-controlled study. J Clin Endocrinol Metab. 2008 Jan 2 [Epub ahead of print]

Alevizaki M , et.al. Low triiodothyronine: a strong predictor of outcome in acute stroke patients. Eur J Clin Invest. 2007 Aug;37(8):651-7.

Pingitore A, et.al. Thyroid function and heart failure: from the new clinical evidences to the potential therapeutical implications. Recenti Prog Med. 2005 Nov;96(11):535-41.

Giorgio I, et.al. Low-T3 Syndrome: A Strong Prognostic Predictor of Death in Patients With Heart Disease. Circulation. 2003;107:708-713

Again, thank you.
Helpful - 1
97953 tn?1440865392
MEDICAL PROFESSIONAL
The increase in rT3 (and lowish T3) is secondary to cardiac events -- it does not appear to increase cardiac events.  TSI is normal and does not itself contribute.  Thyroid function tests are normal and would look elsewhere for the cause of symptoms.
Helpful - 0
Avatar universal
Well, I haven't had any cardiac events though I know Conn's has cardiac implications over time.  I will deal with the Conn's and then try to re-address my low FT3.  I'm thinking the body reduces T3 as a means of some sort of protection.

Thank you for your reply.
Helpful - 0
1313025 tn?1274542577
A related discussion, Need help to interpret labs was started.
Helpful - 0

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