The Diagnosis Debate
Exactly how many people have hypothyroidism in the United States is unclear. The Colorado Thyroid Disease Prevalence Study in 2000 found that as many as 13 million people may not be properly diagnosed.
A diagnosis also depends on where the reference range is set and what your doctor believes. Some doctors may diagnose you with hypothyroidism if your TSH levels are even slightly elevated, while others may not unless levels become significantly high.
To make matters even more complicated, TSH levels fluctuate and may vary with diet, medications, the time of day you have your blood drawn, and the time of year. For instance, during colder months, TSH levels naturally rise. It may also rise when you are taking medications such as lithium or eating too many soy products, which contain iso-flavones that boost TSH. In addition, TSH drops in the early part of pregnancy and rises during the latter part.
The murky nature of diagnosing hypothyroidism has sparked some controversy in endocrine circles. According to the New York Times, the controversy erupted in January 2004, when a panel of experts from several organizations published a report in the
The group — made up of experts from the American Thyroid Association (ATA), the AACE, and the Endocrine Society — said it found no significant scientific evidence to treat patients with mild hypothyroidism, even if these patients were experiencing symptoms. The panel recommended against screening the population for thyroid disease, but suggested that doctors be on guard with high-risk patients, such as older women.
In response, the groups that sponsored the panel disagreed and published a rebuttal in the Journal of Clinical Endocrinology &
Still others take issue with the notion of a “normal” level of TSH. As Mary J. Shomon, a patient advocate and thyroid patient herself, said in the
In any case, the debate over what's normal and what's not is far from over. But it may explain why some people have a hard time convincing their doctors that they do have hypothyroidism, even if their blood tests show values that could be considered abnormal.
What is Wilson's syndrome?
Former physician E. Denis Wilson coined the term for a vague condition characterized by low body temperature and symptoms that resemble hypothyroidism. The American Thyroid Association (ATA) has dismissed the syndrome as having no scientific basis in fact and does not support the use of body temperature as a way to diagnose hypothyroidism. The condition is not to be confused with Wilson's disease, which is a rare genetic condition involving copper metabolism.
One result of this debate is the question of whether to treat people with mild or subclinical hypothyroidism. For patients, this situation has meant that people on the high end of the normal range provided by the laboratory — those with a TSH, say, of 3.0 to 5.0 mIU/dL, for instance — may not be treated for mild hypothyroidism, even in the face of uncomfortable symptoms.
Some experts argue that there is no clear, compelling reason to treat these people before they develop true hypothyroidism. But other medical experts disagree and contend that treatment could help prevent the onset of hypothyroidism.
If you happen to have subclinical hypothyroidism, you should discuss your options with your doctor. If you have no symptoms, you may be advised to adopt a wait-and-see approach, with more frequent testing to keep an eye on thyroid function.
But if you are suffering from bothersome symptoms, you may need to explore your treatment options now. If your doctor is reluctant to treat you, you may want to consider switching to a doctor who is more apt to treat subclinical hypothyroidism.