Exercise-induced arterial hypoxemia (EIAH) related to OSA?

[MCS2014]

I realize it's physiologically normal to show a reduced Sp02 level during exercise. 
 
During a recent (see report below) moderate to intense workout (stepmill), I reached a low of 81 and I stayed <90 for over 7 minutes. My average was 91.
 
According to this article [https://journals.physiology.org/doi/full/10.1152/jappl.1999.87.6.1997], moderate EIAH is 88–93% and severe EIAH is <88%. A sharp initial and gradual drop in Sp02 began after 2 minutes into the exercise, dropping precipitously for another 8 minutes after which it began rising and leveling off at 90-91 (see graph below).
 
Post-exercise Sp02 returned to baseline (96-97).

My Sp02 average during sleep is 95. I usually don't ever see a reading over 97 at rest. I reside in a location with a moderate altitude of ~ 3000' above sea level. 
 
My AHI reading the night prior the workout was 1.61.
 
Would like to know from those that have a better understanding of EIAH in those of us with CPAP-treated OSA whether this intermittent hypoxemia is anything clinically significant (i.e. needing supplemental 02) and if it would merit checking in with my pulmonologist.
 

 

[Ratchick]

I don't know enough about it to really comment but as with everything, if in doubt, ask a doctor. They'd be able to tell you more. But looking at that article, the figures given for different stages are at sea level. With you being at an altitude that has a small but statistically significant effect on SpO2 even in otherwise healthy people, even at rest, so I would imagine that is going to have an effect on exercise-related oxygenation levels too. How much of that time were you exercising for? It's also worth noting that SpO2 recordings using a finger monitor can be notoriously unreliable during exercise too, it's best for your hand to be still to get accurate, consistent measurements.