Highly Irrespectible wrote:
After all that, he incorrectly diagnosed me with Hypothyroid. One of his nurses told me that everyone who comes into their office is diagnosed as Hypothyroid. Of course, that's statistically impossible unless it's medical fraud.
Your thyroid gland works under the control of a classic negative-feedback system: Hypothalamus produces thyrotropin-releasing hormone (TRH), which prods the pituitary gland below to release thyrotropin, or thyroid-stimulating hormone (TSH), which it turn inspires the thyroid gland itself to synthesize thyroid hormone (T3 and T4, the latter usually called thyroxine and having far greater biological activity).
Higher T3 and T4 blood levels both tell the hypothalamus and pituitary to to chill, because TRH and TSH aren't needed when T3 and T4 levels are normal or high. Conversely, when T3 and T4 levels drop, the brain resumes higher production of TRH and/or TSH.
In most cases of primary thyroid failure, the gland doesn't just shut off. Like most endocrine glands that go haywire, it starts to gradually become less effective at doing its job. In response, the pituitary has to bombard the thyroid with increasing amounts of TSH to achieve the same effect. This is called "compensated failure," and of course it can't last forever without medical intervention because a dead thyroid is a dead thyroid. If your car has no gas in the tank, you can stomp on the accelerator all you want, and you'll just sit there and probably blurt out profanities as well.
Given the above, when a doc tests your levels of these chemicals to determine your thyroid status, he or she doesn't just look at how much T3 and T4 is floating around in your system. If your TSH is elevated above normal, your thyroid is possibly, through not always, sliding downhill.
A TSH value of about 0.2 to 4.0 mIU/ml is considered normal. Even if it's slightly elevated, most docs will repeat the test, especially if you have no clinical symptoms of hypothyroidism, because there a number of things other than thyroid issues that can cause an elevated TSH.
http://www.nlm.nih.gov/medlineplus/ency/article/003684.htmJeffrey Brown is considered something of a rogue because he uses a cut-off of 2.0 mIU/ml to make a diagnosis of hypothyroidism. Any higher than that and it's Cytomel, etc. city. I don't know this for sure, but I'd guess that -- at least when it comes to athletes -- even when the TSH is only slightly higher than 2.0, he doesn't repeat the test but immediately writes a prescription for thyroid meds. And it wouldn't surprise me if he does repeat the test when TSH is, say, 1.7 or 1.8, anticpating that on re-testing TSH might fortuitously rise into his personal hot zone.
Dr. Brown believes he has medical justification, and not just swooshy justification, for using a lower TSH cut-off in hard-training athletes. But his various peers in the field of endocrinology are skeptical at best.
April 10, 2013 -- the Wall Street Journal
"U.S. Track's Unconventional Physician"
http://www.wsj.com/articles/SB10001424127887323550604578412913149043072Also see a pharmacist's response, which gives a great overview of the whole topic:
"Is thyroid replacement a performance-enhancing drug?"
https://www.sciencebasedmedicine.org/is-thyroid-replacement-a-performance-enhancing-drug/Over time, thyroid replacement could go one of two ways. It could continue to be treated like inhaled anti-asthma medications, where asthmatic athletes who require treatment would otherwise be at a serious disadvantage in athletic competitions. We’d consider this simply a leveling of the playing field for those athletes. Or it could be that thyroid replacement could be scrutinized even more closely, perhaps requiring better documentation to justify use in an athlete, requiring clearly-demonstrated medical need based on a specific set of parameters, recognizing that there’s thyroid replacement, and then there’s unnecessary supplementation. From my personal perspective, I’m skeptical of medical mavericks who haven’t yet produced enough evidence to convince their peers and change the medical consensus. Until I see the evidence, I’m staying skeptical of Dr. Brown’s approach.