Why standard home test said AHI 8 (twice) but WatchPAT said AHI 46
Hospital's respiratory department had me do the same standard home test once in 2017 and again in 2022. There's a little thingy going in the nostrils (presumably to check breathing), an electrode to be taped on the chest and a finger probe. All of this to be worn the whole night once. In 2017 it yielded AHI = 8, and in 2022 almost the same thing. On that basis I was prescribed CPAP machine with set pressure 10 which didn't help at all (no sleep improvement).
Then a few months ago I did a WatchPAT test which yielded AHI = 46. This was requested by a neuropsychiatrist who asked my GP to refer me back to the respiratory department.
To be sure, my symptoms are consistent with severe OSA which tends to give the WatchPAT results more credence.
Anyway my question is: why the test discrepancy? I heard the WatchPAT is more sensitive than the standard test - is that true?
RE: Why standard home test said AHI 8 (twice) but WatchPAT said AHI 46
When there's different test brands or types, it added variables to the test results. Different years can as well.
The test is also a one night snapshot of Apnea. If you were to look at your OSCAR charts, each night is a little different. You could in theory retest the sleep study every night for a year, and it'll give different numbers.
Which of these 3 is more accurate? I don't know. Do you feel like your untreated AHI is closer to 8 or 46?
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RE: Why standard home test said AHI 8 (twice) but WatchPAT said AHI 46
Without showing the reports hard to say anything useful.....
RE: Why standard home test said AHI 8 (twice) but WatchPAT said AHI 46
watchpat looks like an o2 sensor. o2 sensors show o2 drops or desats. give a thought to maybe the desats are not strictly apnea related. maybe you have something else going on. without seeing oscar it makes the most sense to me. maybe you also need a pulmonologist and an in lab sleep test.
First Diagnosed July 1990
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RE: Why standard home test said AHI 8 (twice) but WatchPAT said AHI 46
Thanks all.
@SarcasticDave94 : my symptoms are severe - chronic mild shortness of breath that goes up if I slept less hours than I need + constant heavy fatigue. I feel like an anaemic 100 years old man (I'm 45). For years I've been wondering what on earth is causing this. Undetected severe sleep apnea is the only explanation that makes sense to me.
Will sleep with machine on as soon as I can to produce data and see what's going on.
