Salivary cortisol tests with high levels?

[fred1e]

Has anyone used the 24hour salivary cortisol tests after having a high blood cortisol (620 on a 7am finger prick test, where high was above 557)

They seem to be used more with adrenal insufficiency, so just wondering if it would be helpful?

[humanbean]

I think the medical profession usually uses saliva cortisol testing during the night when Cushing's Syndrome is suspected. For other purposes it is generally considered by them to be a waste of time. (Patients on this forum would probably disagree.)

A little snippet you may find interesting - NASA uses saliva testing for cortisol and other hormones for their space station astronauts - or used to. I think they now have machines which are like miniature blood testing labs in the space station for finger-prick testing. I don't know if they still use saliva as well.

The saliva and blood tests for cortisol are not measuring the same thing, so it is possible for one to be very high and one to be very low.

Are you aware of the difference between Total T4 and Free T4? And that Free T4 is more reliable and informative than Total T4?

You can think of blood cortisol testing as measuring Total Cortisol, and saliva cortisol testing is equivalent to measuring Free Cortisol, although nobody ever uses those terms. I find they help me to envisage what is actually going on.

Free Cortisol (from saliva) is exactly what it suggests - it is "pure" cortisol.

Total Cortisol (from blood) is measuring Free Cortisol + Cortisol which is attached to transport proteins which move cortisol around the body.

The body needs to be able to attach and detach transport proteins from cortisol as and when necessary. The body can make immediate use of Free Cortisol, but not Total Cortisol.

From anecdotal results discussed on this forum I think that T3 might have something to do with the attaching and detaching of cortisol from its transport proteins. But I'm neither a doctor nor a scientist, so take that with a pinch of salt.

[Hidden]

You could do the salivary cortisol test but you would be better asking your GP to do an early morning serum cortisol & a 24 hour urine to see if they show your cortisol is high. The oestrogen contraceptive pill, HRT & Biotin (found in some supplements) can give an elevated result so if you're on them you need to come off them for 6 weeks prior to testing. Being on long term steroids can also give elevated results. What symptoms are you experiencing? High cortisol can point to Cushing's syndrome, symptoms are weight gain round the trunk, round, flushed face, insomnia, excess facial hair, thinning hair, elevated BP & possibly muscle weakness.

[fred1e in reply to Hidden]

Thank you...no I'm not on any of the above, and GP early am cortisol is similarly raised....

My endo has asked for a 24 hour urine collection, but for some reason, GPs are having a problem organising this with their lab, hence looking at salivary tests.

Endo has also asked for low dose dex suppression test.... but wanted to check 24 levels first.

[Hidden]

That's good that your GP is investigating further, Cushing's is not a nice condition to have so I hope you don't have it. I've had it due to a benign pituitary tumour so if I can help, just ask. If you are on FaceBook then there is a support group called Cushing's UK which can help you & give you lots of advice.

[fred1e in reply to Hidden]

Thank you.....I think it is more precautionary testing as I don’t have full symptoms.....also mine is unlikely to be pituitary as I had an mri for central hypothyroidism last year, but do have other results that could point to the adrenal side of things!Isn’t life “fun” sometimes!

[Hidden]

Oh absolutely!! My life seems to be spent going to hospital appointments!!