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Avatar universal

'Normal' TSH ? LOW TSH and Heart Problems/ HIGH TSH and Heart Disease

Dr. M L, I've read several messages where you've referred to studies that say low TSH (<.3) causes heart problems. Were these studies done on patients taking T4 only synthetic (Synthroid)? Were they hypO or Graves patients? I'm concerned so could you please tell me where I can find the reports on those studies? Following is a study-"Proper Treatment of Hypothyroidism Found to Prevent Heart Diseases":

I've had untreated HypO for years but now I'm symptom-free. I've been on the same Armour dose 10 mos. My TSH is below .00 depending on when I took my last dose. I had 4 TSH tests done in a 6-hour period:

2.8 TSH at 8am-(17 hrs after last Armour dose),
.0001 TSH at 9am-(1 hr after 180mgs);
.018 TSH at 11am-(3 hrs after 180mg); and
1.02 TSH at 2pm-(6 hrs after 180mg and 1 hr before my 2nd dose of 180mgs).

I've had no hypER or hypO symptoms. In your opinion, am I at risk for heart damage, anyway? Should I decrease my dosage and risk hypO symptoms returning?

It's been reported that 1.0 TSH is normal for most people not taking thyroid replacement. Have any studies been done concerning a "normal" TSH # for those of us taking thyroid hormone? Because the hormone circulating in our blood causes the TSH result to vary so much as my tests show, aren't symptoms much more important than TSH #'s when it comes to dosage adjustment and heart damage? Are thyroid patients at risk for heart damage anyway? Shouldn't more studies be done?

Thank you in advance for your time and answers to my questions.


28 Responses
97953 tn?1440868992
Of course more data is needed on thyroid and heart disease - the risk of a low TSH and heart disease is increased with advanced age (typically greater than 65) - this is in population studies usually in patients not on thyroid hormone, but expert opinion is that a low TSH in a pt on thyroid is at risk as well (again, esp with advanced age).  The 6h study is interesting - shows the powerful TSH suppression of relatively high dose armour (ie 3grams).  Honestly, the studies have not specifically looked at this situation, so in absence of palpitations, chest pain, history of heart disease or risks for heart disease (diabetes, tobacco, high cholesterol, hypertension) it may not be dangerous in a young healthy person -- there is no "one size fits all" answer to the question.

Certainly, untreated hypothyroidism can worsen heart disease as well but currently treating to a TSH <0.3 (give or take) is not considered advisable by most international experts.
Avatar universal
I'm with you...with an undetectable TSH and absolutely no hyper symptoms..and in fact, still struggle a bit with hypo symptoms at times.  I don't know how the docs have confused a suppressed TSH from true hyperthyroidism with those with a suppressed TSH because of the normal HPT feedback loop being disrupted with oral thyroid hormone replacement.  

But thank goodness some docs are not confused.  I was just reading Dr. Starr's new book, Hypothyroidism Type 2...and like Dr. Hotze's new book, Hormones, Health, and Happiness...and both of them get it right. I wish all doctors would read these books...it would help so many.  These docs, like some other older thyroid docs, know that TSH only picks up a small portion of hypothyroidism...and they know that blood tests can be quite useless in treating hypothyroidism.  I have never quite figured out how a doctor can think a person is hyper when their temp is still low, their blood pressure and pulse are normal, and they are struggling to resolve lingering hypo symptoms...

Avatar universal
Rella, if you look at most studies that doctors cite which involve low TSH, they were either on patients who were on NO meds and were true hyperthyroid, OR they were on patients who were on T4-only meds! I belong to a group called Natural Thyroid Hormones on Yahoo, and it appears that the VAST majority have suppressed TSH's like yours.....and...they are NOT dosing by the TSH. They appear to be dosing by symptom elimnation first, and using the free T3 as a guide rather than the TSH. They have an EXCELLENT Files section to show why they do what they do, and some articles which refute what is being told to us---i.e. refutes dosing by the TSH, and definitely refutes taking T4-only meds. They also state that the real risk to our hearts is in REDUCING Armour simply to abide by the current "rule" that one must go by the TSH. Because when a person "reduces" their Armour to go by the TSH, they also "reduce" the thyroid hormones that puts them in a non-symptom state......and that reduction also increases risks from being chronically hypothyroid.......i.e. UNDERtreated. So in my mind, and in the minds of what appears to be thousands of folks like ourselves who have switched to Armour, going by SYMPTOMS is proving far superior than going by a fallible and changing TSH....in all due respect.
Avatar universal
"I have never quite figured out how a doctor can think a person is hyper when their temp is still low, their blood pressure and pulse are normal, and they are struggling to resolve lingering hypo symptoms... "  Mshypo, you couldn't have said it better. Why doctors think that a TSH is the end-all to treatment in spite of and in lieu of obvious symptoms or lack of.....boggles the mind.
97953 tn?1440868992
The TSH debate continues....it is certainly not the end-all test and we all welcome the day when we have tests that reflect tissue level thyroid activity -- until then, in order to make general treatment recommendations we need to rely on studies that suggest a low tsh may be harmful in certain patients -- body temperature is not dependable to reflect thyroid function.  There are certainly other opinions that are well marketed and described -- however, in mainstream thyroidology we depend on studies and expert consensus -- again the individual patient evaluation supercedes any generalized statement that can be made.
Avatar universal
Dr. Mark, it is refreshing to read an Endocrinologist like yourself state that the TSH is not the end-all test, because AACE and so many of your colleagues are rigidly stating that fact ABOVE AND BEYOND the continuing symptoms of patients who are kept in that TSH range. And if a patient on Armour takes enough Armour to rid themselves of symptoms...and has a suppressed TSH...it's the Endocrinologists who are screaming bloody murder and insisting that the patient in now "hyper" and that the patient needs to decrease their Armour, even though there are NO symptoms of hyper and even though decreasing Armour to get the patient back "in range" also causes hypo symptoms to return!

But when you state that you have to rely on studies---those studies are based on patients who are either true hyper, or on patients on T4-only meds, and no studies are addressing those who are on Armour, which changes that feedback loop! So, because of inadequate "studies" (and because of the huge financial power of Abbott labs), patients are being told to decrease or dose according to a TSH and inadequate studies.

When did "studies" and "mainstream thyroidology" become more important than obvious symptoms, or more important than patients who are finally symptom-free, yet are told to decrease their meds so they can fall within an arbitrary range??
It's ludicrous.

But, you also stated that "the individual patient evaluation supercedes any generalized statement that can be made", and that is hopeful. Because there appear to be thousands upon thousands of us..of individuals..whose experiences with Armour and with dosing NOT by the TSH are DISPROVING those "studies" and that "mainstream thyroidology".

Avatar universal
The prior post was to Chocobabe & you.  Thanks
Avatar universal
My TSH has been suppressed to under 0.01, you could say nonexistant. When my Ft4 and Ft3 are not in the upper 1/3 of the range, I have depression, anxiety,low body temperatures.

I did have RAI for Graves disease.
Avatar universal
I want to ditto Nurse's comments.  Where is Dr. Mark located?  Wish he was here in Houston. He has been very helpful.  I am on 3 Grams of Armour and thanks to Dr. Mark I am taking 1/2 in AM and 1/2 in PM.  I have had bouts of Tach and A-bib.  I most likely will switch to Synthroid very soon.
Avatar universal
Yes, I did mean 3 Grams....And it is A-FIB and not A-BIB.  I need spell check...LOL

I never had a ferritin level checked in my 55 years and asked for one this summer.  It was 16.  I asked for a repeat...It was 14.  I asked for another repeat and it was 12.  All done by Quest Labs.  The docs were not concerend.  And, now I have adenoma on the Rt. Thyroid.  I am a mess.  And on top of this..heart disease. I really feel that the Thyroid has been the culprit to my problems and I feel like *&%^%^%*8!!! I even have problems breathing.  I am finally other seeing an Endo next week,  The other 2 Endo's I saw a few years back should be put to pasture.  My GP has been very good but now he is stumped.
Avatar universal
Even though I am a nurse, I am certainally no expert on thyroid, but I have experienced hypothyroidism since the early 80's & then last year I was treated for hyperthyroidism due to Graves. Until the symptoms got so pronounced, that they almost stopped me in my tracks, it was hard for me to differentiate hypo from hyper.. Yes their are some suttle differences, but many symptoms are alike, i.e. generalized weakness, muscle aches, brain fog, breathlessness, hair loss, ridges on fingernails, palpitations, goiter, just to name a few. Also I had low blood pressure when I was hyper., not everyone has the same symptoms. Until my symptoms escalated into full blown hyperthyroidism I could not tell the difference. Then the other hyper. symptoms came into play & believe me you don't want to go there. My hyper status was documented first in my TSH long before my symptoms escalated. I also now know I was experiencing periods of extreme hyperactivity that would come & go for at least 3 yrs.prior to my diagnosis . But like hypo symptoms they come on so slowly you don't even realize they are there until they are out of control. If my hyper state would have been caught earlier my immune system may not have attacked my thyroid or my eyes & it may not have affected my health so much. My TSH was consistently <.03 for almost nine years before my diagnosis but seeing I wasn't having any hyper symptoms I was maintained on the same dosage of Synthroid & my Free T's weren't checked. But this was done that way because I was asymptomatic. The one thing I would like to advocate is that (Family Physican's) be educated to always check the free T-3 & free T-4 with the TSH. Especially if the TSH is low.  I feel you must combine the lab results including the TSH with the symptoms of the pt., as Dr. Mark has said.  But you can't just go by symptoms. TSH, free T-3 & free T-4 are important too..
I'm not saying that one med is any better than another, that too depends on an individuals reaction. I have taken both Synthroid pre-hyperthyroid & now Armour post-hyperthyroid treatment & have had good results with both of them.
I'd like to say thank you to Dr. Mark for making this disease so much easier for us to deal with & offering your knowledge so freely. I wished I could have been able to talk with you while I was undergoing treatment for my hyperthyroid state. I know I have gained alot of knowledge from you so far. It's great to have an Endocrinologist at our finger tips. Thanks again.
Avatar universal
Yes, the TSH debate continues..as every test to check thyroid function has been debated...and eventually discarded.  Haven't they all had problems and haven't they all been discontinued eventually?  I do not understand how the medical establishment has gotten away from what worked - diagnosing hypothyroidism from the patient's medical history, symptoms, and physical findings.  

As for stating "body temperature is not dependable to reflect thyroid function", I believe it might well be true that is is more dependable than the TSH lab test as lowering of body temperature is an extremely prevalent symptom of hypothyroidism.  True, hypo is not the only problem that may lower the patient's temperature, but it is definitely the most common reason...and this is being ignored by the vast majority of doctors. My own experience is that I had a lowered temperature for over a decade before my TSH rose high enough to get a hypo diagnosis.  My life would had been entirely different if docs had looked at low body temperature and symptoms instead of saying "normal" because of a faulty TSH test.

As for those tests regarding a low TSH that you refer too, investigation reveals those tests are all about true hyperthyroidism and not for those on oral thyroid hormone replacement.  In fact, it would appear that the real threat to a hypo person's health is remaining hypo due to undertreatment due to dosing by the TSH.  
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