There is an ongoing debate over whether to treat subclinical thyroid hypothyroidism (where TSH is more than 4.5, but less than 10, and levels of free thyroxine (FT4) and triiodothyronine (T3) are within the reference range).
The debate continues with an article by Dr. Martin Surks and his colleagues in a recent article in the Journal of the American Medical Association. For the article, a panel of endocrinologists, as well as experts in lipid disorders, cardiology, women's health, evidenced-based medicine and screening, convened to determine whether subclinical hypothyroidism should be treated.
According to the researchers, there is little data that connects subclinical thyroid disease with symptoms or adverse clinical outcomes. The researchers declare that there are minimal consquences of subclinical thyroid disease, and they we recommend against routine treatment of subclinically hypothyroid patients. The only circumstance in which they recommend more routine screening for or treatment in pregnant women, women older than 60 years, and others at high risk for thyroid dysfunction.
According to the American Thyroid Association, these results should "stimulate support for large prospective randomized trials of treatment of subclinical thyroid disease. The emphasis for clinicians should continue to be on testing those who are symptomatic or at high risk for thyroid disease, including those with a family history of thyroid disease, other autoimmune disorders including Type I diabetes, vitiligo, and premature menopause. Finally, the ultimate treatment decision must involve the clinician considering multiple factors; their clinical evaluation and judgment, patient preference, clinical outcome studies, potential risks of overtreatment with levothyroxine, and new bodies of evidence from well-designed studies that are logical and grounded in well-established principles of pathophysiology."
Source: Surks, et. al. "Subclinical Thyroid Disease: Scientific Review and Guidelines for Diagnosis and Management," JAMA, Jan 2004; 291: 228 - 238.
Mary's Comments
This research is another example of short-sighted, shoddy work by the nation's endocrinologists. I don't know what body of research these fellows were looking at, but obviously, they missed some recent articles that found that:
- Subclinical hypothyroidism treatment can reduce cholesterol levels and the risk of death from heart disease (Source: "TSH-controlled L-thyroxine therapy reduces cholesterol levels and clinical symptoms in subclinical hypothyroidism: a double blind, placebo-controlled trial (Basel Thyroid Study)," Journal of Clinical Endocrinology and Metabolism, 2001 Oct;86(10):4860-6)
- Treatment of subclinical hypothyroidism reduces the risk of athersclerosis (hardening of the arteries.) (Source: May, 2003 American Association of Clinical Endocrinologists 12th Annual Meeting and Clinical Congress)
- Even when TSH levels are normal, if a patient tests positive for thyroid antibodies, treatment with thyroid hormone replacement may prevent full-blown hypothyroidism (Source: Thyroid, 2001 Mar;11(3):249-55, "One-year prophylactic treatment of euthyroid Hashimoto's thyroiditis patients with levothyroxine: is there a benefit?"
Until November 2002, doctors had relied on a normal TSH level ranging from 0.5 to 5.0 to diagnose and treat patients with a thyroid disorder who tested outside the boundaries of that range. Now AACE encourages doctors to consider treatment for patients who test outside the boundaries of a narrower margin based on a target TSH level of 0.3 to 3.0. AACE believes the new range will result in proper diagnosis for millions of Americans who suffer from a mild thyroid disorder, but have gone untreated until now. (Source: AACE Thyroid Awareness Month 2003 Press Release)
Do these researchers not read their own research journals when they put together these "review" studies? Are they bound and determined to remain blind to the fact that many subclinically hypothyroid patients DO have symptoms? Will they go against their OWN recommendations to continue to leave millions of Americans subclinically hypothyroid, suffering, and facing an increased risk of heart disease, obesity, infertility, depression, and many other symptoms?
Back to the drawing board, guys!
