Bone Risk in Thyroid Treatment
Most women have probably already heard enough about osteoporosis to know whether they really need to worry about it. Most women do have to worry, at least here in the United States. Here's a reminder of the factors that affect your risk: good to the right, bad to the left as you go down. Not having a "good" factor means you have risk on that basis.
Here are three sets of information for evaluating the risk of hyperthyroidism for your bones:
1. Literature search (July 2001); updated 12/2011
2011 Update: Reviewing this literature again, I found a few more reports. Several are describing lower bone density among post-menopausal women taking high dose thyroid (not premenopausal women, compared to women of the same age not taking thyroid). Looks like getting bone density studies after menopause, and taking at least calcium if not hormone replacement, make sense. (The additional reports: Thailand, Taiwan, UK; these are similar to yet older reports cited by Dr. Klein in the thread below.)
2. The opinion of Don Klein, a well-known psychiatrist who has reviewed this issue extensively -- and others.
Here is Dr. Klein in an email discussion of the issue with colleagues ( if you want to read the whole thing, pretty technical but including the similar opinions of other doctors, click here) :
Date: Sun, 11 Feb 1996 00:52:29 -0500 (EST)
From: Donald Franklin Klein <firstname.lastname@example.org>
Subject: Thyroid replacement
The major medical red herring is osteoporosis which is a problem in postmenopausal women correctable by estrogen. [italics mine; he's saying he does not regard osteoporosis as a problem in premenopausal women taking thyroid replacement, consistent with the research linked in section 1 above]
For useful medical references try:
Wartofsky L. Levothyroxine therapy and osteoporosis. An end to the controversy? Archives of Internal Medicine. 155 (11): 1130-1, 1995 Jun 12
Florkowski CM, Brownlie BE, Elliot JR, Ayling EM, Turner JG. Bone mineral density in patients receiving suppressive doses of thyroxine for thyroid carcinoma. New Zealand Medical Journal. 106 (966): 443-4, 1993 Oct 27.
There is a turf battle here but I handle thyroid myself rather than depend on an unstable alliance.
I use T3 + T4 and aim for .1 mg T4 + 50 mcg T3. For uselessness of thyroid indices once exogenous thyroid given, see Fraser WD et al. Are biochemical tests of thyroid function of any value in monitoring patients receiving thyroxine replacement? Brit Med J. 293:808-810, 27 Sept 1986.