Longitudinal changes in thyroid function in the oldest old and survival: the cardiovascular health study all-stars study.
J Clin Endocrinol Metab. 2012 Nov;97(11):3944-50. Waring AC, Arnold AM, Newman AB, Bùzková P, Hirsch C, Cappola AR.
Data on thyroid function in the oldest old are sparse, and existing studies show conflicting evidence on the relationship between thyroid function and mortality in this age group. We describe longitudinal changes in thyroid function in a cohort of elderly individuals and determine the relationship between thyroid function and mortality. Eight hundred forty-three participants in the Cardiovascular Health Study All Stars Study who were not taking thyroid medications and had thyroid function testing in 2005-2006 (mean age 85 yr). Thyroid-stimulating hormone (TSH), free T(4) (FT4), total T(3), and thyroid peroxidase antibody status were measured in 1992-1993 and 2005-2006. Deaths were ascertained through February 2011.:
There was a statistically significant 13% increase in TSH, 1.7% increase in FT4, and 13% decrease in total T(3) over the 13-yr period. Two hundred eighty-seven deaths occurred over a median follow-up of 5.1 yr. There was no association between subclinical hypothyroidism[hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.66-1.43], TSH level (HR per milliunits per liter 0.94, 95% CI 0.88-1.01), or persistent thyroid peroxidase antibody positivity (HR 1.09, 95% CI 0.62-1.92), and death. However, FT4 was positively associated with death (HR per nanograms per deciliter 2.57, 95% CI 1.32-5.02).
TSH increased over time in these older individuals. This elevation was not associated with increased or decreased mortality, although higher FT4 levels were associated with death. These findings raise concern for treatment of mild elevations of TSH in advanced age. Further studies are needed to determine the potential benefit of treating age-related changes in thyroid function.
COMMENT-One hypothesis offered is that a decline in pituitary sensitivity leads to mild elevation of FT4. The correlation between increases in FT4 and mortality suggest caution in treating mild elevations in TSH in the elderly.
Longitudinal changes in thyroid function in the oldest old and survival
Download PDFThank you for using and supporting THYROID MANAGER
One click download of a complete current PDF version of this chapter is available by payment of $5.00 (including sales tax) to ENDOCRINE EDUCATION / MDTEXT.COM,INC.
Please note:
You will be directed to a Paypal site for entering payment information, and then returned immediately to this site for delivery of the PDF download. If you do not wish to secure the PDF version, you are of course free to download the material directly from the chapter on our Website without charge.
We welcome comments on this service, and this charge, to- ldegroot@earthlink.net. May we note that we must secure income from advertisements and chapter downloads in order to continue providing our (otherwise) totally free, comprehensive, authoritative, constantly up-dated, Endocrinology web-book to the thousands of physicians and trainees around the world who visit the website each day of the year. We also welcome contributions.