I have tapered to 5mg using Dorset Lady’s 5 week taper. Curiosity got the better of me and last week I had an am cortisol test done. The lab where I had the test said it had to be done before 10am. I was aware that the earlier in the morning the better, but because I take my thyroid medication first thing in the morning, I usually end up taking my prednisone around 11am. I didn’t take my prednisone until after I had the blood draw, which was around 9:45am. The test results placed me right in the middle of the normal range. My question is, if I should have had the test closer to 8am, how would my taking it later influence the results? Would they tend to be lower than had I had the draw earlier? Just wondering if this test result is meaningful at all or if I wasted my money
Thanks!
AM Cortisol Test: I have tapered to 5mg using... - PMRGCAuk
AM Cortisol Test
For the basal cortisol test it is actually fine to take the blood sample at any time between 9am and 1pm, it doesn't affect the meaning of the result.
pubmed.ncbi.nlm.nih.gov/317...
Thanks! This is very helpful. My follow-up question is if I had the draw slightly under 24 hours from my last prednisone, would that influence the test? It was slightly less than an hour short of 24 hours when I had the draw.
If anything it would have suppressed the level but obviously it didn't suppress it much if you were in normal range - the trigger for cortisol production is a very low level at midnight-ish. The halflife for pred is usually taken as 3-4 hours, it takes 5 half lives to effectively get all of a drug out of your system - if it is 4 hours that is 22 hours, if it is 3 hours it is 17 hours. Either way, 21 hours is more,
What WAS the reading? Or were you just told, in the normal range? I only trust numbers ...
I would never settle for just being told I was in the normal range I am in the states and our lab values seem very different from those in the UK. The range for my lab is 6.2 to 19.4 (ug/dL) and my result was deemed normal at 12.5.
At the risk of repeating myself, I am incredibly grateful for your wealth of knowledge on PMR and GCA. I learn more from you than at any physician’s appointment. I have great doctors, but there are gaps in their PMR/GCA knowledge that you and Dorset Lady and several others in our wonderful support group are able to fill in. Thank you!
what does affect the results is the fact that you are on 5 mgs of Prednisalone therefore your Cortisol needs are being met by the drug. You get a more accurate result from 3 mgs, I believe. I did fail my test at 5 mgs ( my own function with no Pred) and passed as normal at 3 mgs. Presumably my body had spotted the lack and upped its game.
That’s interesting SJ - I had this test recently while on 4.5 mgs and failed - was told I should stay on that dose ad infinitum not go down any further. I am to see him again in 6 months though…
No, you taper VERY slowly and carefully to see if it will improve, it probably will. What they SHOULD do is teach you how to recognise symptoms of adrenal crisis and possibly provide you with a rescue pack of hydrocortisone. If you were still to consistently fail at lower doses then they would have to consider keeping you on a replacement dose. But there are several on the forum who "failed" at 5, had a poor result at 3 but normal at 1,5mg. The only way to get back to normal is to persist at a lower dose, with safety netting, until the adrenal function returns to more like normal - but that can take up to a year after stopping pred altogether.
Thanks PMRpro - that feels like the right way to go. Now to persuade Endo and Rheumie to see it that way!
They have to remember that this is adrenal insufficiency SECONDARY to being on longterm pred and that the aim is to get off pred in the end providing the PMR allows it. It usually does even if it doesn't seem like it sometimes, The only way to get adrenal function back is to taper slowly - if you don't try it will never happen. I'm surprised they don't know that ...
My Rheumy, who knows these things because "I have delt with several patients with PMR", has stated that both Basal Cortisol and Acth tests are pointless until one is completely off Pred. (She also has a hang-up about sleeping with only one pillow?) She is, of course, completely failing to understand the point and it worries me just how many problems, maybe even serious ones, she has caused her "several patients".
Couldn't agree more. SEVERAL patients - golly, I suppose that makes a change from the woman who claimed to have managed thousands of GCA patients in her career ,,, There is not much point having an ACTH test and wasting time and money possibly but a basal cortisol is cheap and easy, can be done by the GP and shows if it might be worth doing the ACTH test. There are people with normal levels and others with intermediate basal cortisol levels and following that can show if any progress is being made. Having a half decent intermediate level probably means you can get off daily pred to see if it improves but keep the emergency pack just in case. Just makes me think that a lot of doctors have lost the ability to think logically ...
On the other hand, thousands HAVE passed through these portals and in 10 years plus on the forums, I have only come across a couple who didn't get off pred because of adrenal function being inadequate.
Like PMRpro I am curious to know the actual levels. And what is considered normal range? I tested 368 at 30mins and 420 at 60mins which caused my rheumie to say that I have adrenal insufficiency and to stay on 4mg for the foreseeable future, although I am seeing him on 2 October so we will discuss then and I will also taper as I feel able to in any case.
Please see my answer to PMRpro. In the states our labs have a different normal range.
Ah yes, I see. I missed it earlier. Can't really make a comparison I guess
You didn’t miss it. I just posted it.
What’s the normal range for your lab values?
Well the rheumie said he wanted to see 450 at 30 mins ideally
I found this just now:
A normal response to the ACTH stimulation test is an increase in the serum cortisol level.
In people with normal adrenal reserve, cortisol levels increase to more than 500–550 nanomol/L after 30 or 60 minutes.
In people with adrenal insufficiency, serum cortisol levels do not increase adequately in response to tetracosactide because the adrenal cortex is already receiving maximum stimulation from endogenous ACTH.
[Arlt, 2003; Bornstein, 2009; Vaidya, 2009; Wallace, 2009; Chakera, 2010; Husebye, 2014; Bancos, 2015]
Ah, I think we had different tests. My was an AM Cortisol blood test and it sounds like you had the synacthen test.
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