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 (American Association Endocrinologists) 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.” “In the future, it is likely that the upper limit of the serum TSH euthyroid reference range will be reduced to 2.5 because 95% of rigorously screened normal euthyroid ( the state of having normal thyroid function) volunteers have serum TSH values between 0.4 and 2.5 mIU/L.”
“A serum TSH result between 0.5 and 2.0 mIU/L is generally considered the therapeutic target for a standard T3-T4 replacement dose for primary hypothyroidism.”
“The prevalence of undiagnosed thyroid disease in the United States is shockingly high – particularly since it is a condition that is easy to diagnose and treat,” said Dr. Gharib. “The new TSH range from the AACE guidelines gives physicians the information they need to diagnose mild thyroid disease before it can lead to more serious effects on a patient’s health – such as elevated cholesterol, heart disease, osteoporosis, infertility, and depression.”
People who had family histories of thyroid disease, symptoms (including enlarged thyroid, goiter, nodules, etc.) but whose TSH tests were in the low or high end of normal were routinely denied treatment, and sent away with no diagnosis and no treatment. This narrow-minded means of diagnosis has been the “standard of care” for conventional doctors and endocrinologists for decades, based on a near- slavish reliance on the TSH test — often to the exclusion of clinical evidence, symptoms and medical observation.
Third, and equally of concern, many people with symptoms, whose TSH levels fell into the high or low-normal, were told that their problems were actually the result of depression, and given antidepressants. This means that a percentage of the population was misdiagnosed, sometimes stigmatized by the diagnosis of mental illness, and unnecessarily given drugs.