Thyroid function tests during substantial weight change Writing it up because I had to work it out twice and would rather nobody else did.
What changes if the standard account of Thyroid function tests during substantial is wrong? I ask because I have been treating it as settled and I noticed this week that I could not say why.
Working through the consequences rather than the evidence, since others here are better placed on the evidence.
Post #22 describes the usual case. This is about the unusual one.
Ask what decision the result would change before ordering it. A test whose result changes nothing is a test that generates worry rather than information.
Analytical imprecision: any measurement has an error margin. A small difference in consecutive tests is usually measurement noise, not a real change. Knowing the imprecision helps distinguish noise from signal.
Written quickly, so the reasoning may be tighter than the wording.
The arithmetic in post #31 is right; the assumption feeding it is the part to check.
Liver enzyme changes during rapid weight loss are commonly reported and have several possible explanations, which is exactly why they need clinical interpretation rather than forum interpretation.
Not disagreeing with anyone above, just adding the bit I keep having to look up.
Lipid changes during substantial weight loss are expected and their trajectory is not always monotonic. A single mid-course panel can be misleading.
Confirming post #54 from a second method, which matters more than confirming it from a second person.
Glycaemic markers integrate over different periods. A point glucose and a longer-term marker disagreeing is not a contradiction; it is two different questions.
The reason Thyroid function tests during substantial is hard to answer is that the obvious measurement and the relevant quantity are not the same thing, and substituting one for the other is silent.
Sensible. I would want the same detail before I acted on it either.
Read the full topic (75 posts)
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