Article to share with physicians who aim for mid-to-high "normal" TSH range (and keep you tired and miserable).

[wombatty]

Flynn RW1, Bonellie SR, Jung RT, MacDonald TM, Morris AD, Leese GP. Serum thyroid-stimulating hormone

concentration and morbidity from cardiovascular disease and fractures in patients on long-term thyroxine

therapy. J Clin Endocrinol Metab. 2010 Jan;95(1):186-93. doi: 10.1210/jc.2009-1625. Epub 2009 Nov 11.

Abstract

CONTEXT:

For patients on T(4) replacement, the dose is guided by serum TSH concentrations, but some patients request higher doses due to adverse symptoms.

OBJECTIVE:

The aim of the study was to determine the safety of patients having a low but not suppressed serum TSH when receiving long-term T(4) replacement.

DESIGN:

We conducted an observational cohort study, using data linkage from regional datasets between 1993 and 2001.

SETTING:

A population-based study of all patients in Tayside, Scotland, was performed.

PATIENTS:

All patients taking T(4) replacement therapy (n = 17,684) were included.

MAIN OUTCOME MEASURES:

Fatal and nonfatal endpoints were considered for cardiovascular disease, dysrhythmias, and fractures. Patients were categorized as having a suppressed TSH (<or=0.03 mU/liter), low TSH (0.04-0.4 mU/liter), normal TSH (0.4-4.0 mU/liter), or raised TSH (>4.0 mU/liter).

RESULTS:

Cardiovascular disease, dysrhythmias, and fractures were increased in patients with a high TSH: adjusted hazards ratio, 1.95 (1.73-2.21), 1.80 (1.33-2.44), and 1.83 (1.41-2.37), respectively; and patients with a suppressed TSH: 1.37 (1.17-1.60), 1.6 (1.10-2.33), and 2.02 (1.55-2.62), respectively, when compared to patients with a TSH in the laboratory reference range. Patients with a low TSH did not have an increased risk of any of these outcomes [hazards ratio: 1.1 (0.99-1.123), 1.13 (0.88-1.47), and 1.13 (0.92-1.39), respectively].

CONCLUSIONS:

Patients with a high or suppressed TSH had an increased risk of cardiovascular disease, dysrhythmias, and fractures, but patients with a low but unsuppressed TSH did not. It may be safe for patients treated with T(4) to have a low but not suppressed serum TSH concentration.

PMID: 19906785

[eeng]

Good stuff. And part of the reason that people with a suppressed TSH have a less healthy existence is that the main groups of people with suppressed TSH are 1. Those who have no Thyroid due to having had thyroid cancer and 2. People who are hyperthyroid e.g. with Graves disease.

[TSH110]

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[TSH110]

My mother and sister both had thyroid cancer and felt/feels fine on levothyroxine. My sister is a tiny build compared to me but I was amazed she was in 175mcg Levo but I was on125mcg and they even insisted on reducing this although I still had marked hypo symptoms and despite my protestations. I have felt rubbish for three years thanks totally to undermedication and have taken the law into my own hands. a

I feel infinitely better self medicating on NDT but only to the equivalent dose according to the TPA guidelines. It was only reading stiff on here that I realised the real reason why my mum and sister felt so well on Levo. Not the complete clap trap i was told by the thyroid nurse about parathyroids when I quizzed her as to why my dose was so low in comparison. I no longer have heart pains for the first time in years.

[wombatty in reply to TSH110]

Doctors are afraid to give us more T4 than it takes to keep us breathing and our hearts beating because it's been drilled into them that being hyperthyroid can cause potentially fatal heart arrhythmias, so they compulsively keep our TSH in the upper 50% of the targert range or higher. (In the US, I think the fear is as much of being sued as of harming a patient.) This article is the first I've found investigating cardiovascular and/or other adverse outcomes among people without other major risk factors (e.g., diabetes) who are being treated with T4 and whose TSH is within or below the target range for someone on T4. The results show pretty clearly, in my opinion, that we're in greater danger of CV events in the medium-to-high part of the range than in the low-normal region. They also suggest, however, that unless the thyroid is being suppressed to prevent recurrence/metastastases of thyroid cancer, it's safer not to get the TSH that low. I'd be overjoyed to be allowed to maintain at 0.5. Unfortunately, my endo will receive the results of my latest tests before the article reaches her, as I was unable to fax it and had to resort to snail mail.