Today, the British Medical Journal’s website published my “rapid response” letter:
How can truly hypothyroid patients be accurately diagnosed within the enlarged subclinical category?
Link to full text: https://www.bmj.com/content/365/bmj.l2006/rr-6
It is a response to the new guidelines for subclinical hypothyroidism:
Bekkering, G. E., Agoritsas, T., Lytvyn, L., Heen, A. F., Feller, M., Moutzouri, E., … Vermandere, M. (2019). Thyroid hormones treatment for subclinical hypothyroidism: a clinical practice guideline. BMJ, 365, l2006. https://doi.org/10.1136/bmj.l2006
Quotes
“My main concern with the new guidelines is for the health of patients who are truly hypothyroid despite TSH and T4 levels that place them within the now broader subclinical hypothyroidism category.”
“I believe ‘false-negatives’ will genuinely suffer without appropriate therapy if they are over 30 and not pregnant. A person is a false negative when they are denied the diagnosis and therapy for overt hypothyroidism because they are miscategorized as subclinical.”
[…]“If the TSH-T4 paradigm contributed to overtreatment and ineffective therapy, and if this paradigm resulted in many false positives, then how is it helpful to expand the gray area created by this paradigm, use it to make the subclinical category even wider, and then forbid therapy within that category? This creates a larger gray area for false negatives.”
“I propose a better way forward: Acknowledge the flaws of the TSH-T4 diagnosis paradigm, and then take steps to improve thyroid diagnosis. Surely medicine wishes to prevent harm. Identify the genuinely hypothyroid patients in this category.”
[…]“The symptoms of hypothyroidism are commonly dismissed by logical fallacies. The reasoning is that because the symptoms of hypothyroidism _can_ be caused by other health conditions, they _are_ caused by other health conditions, especially if the TSH and T4 levels persuade. But symptoms are the natural physiological effects of T3 hormone insufficiency, not the direct effects of TSH or T4. To say that all the classic hypothyroid symptoms are ‘nonspecific’ to hypothyroidism leaves no symptoms that are specific to hypothyroidism.”
“The guidelines in Box 3 state that ‘there is no clear evidence on how to attribute symptoms to SCH reliably, even with severe symptoms’ — this is not true.”
[…]“Many relevant tests have been buried and forgotten by a medical paradigm that claimed TSH and T4 testing was enough – and this very paradigm led to the charge of ‘ineffective’ overtreatment of healthy patients within the vague subclinical category.”
[…]- Tania S. Smith
REFERENCES
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Competing interests: No competing interests
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