Normal AHI readings

I have read in the past that it is normal for everyone to have some hypopneas. So if that is correct, if you set the machine on the lowest pressure (i.e. 4) does anyone know what AHI readings a person without OSA would get?

someone more knowledgeable than I will be along shortly I'm sure but for diagnosis purposes they don't treat below 5 so perhaps that's one definition of "normal".

bouncer wrote:I have read in the past that it is normal for everyone to have some hypopneas. So if that is correct, if you set the machine on the lowest pressure (i.e. 4) does anyone know what AHI readings a person without OSA would get?

no

would be differant with every person

AHI is the number of apneas or hypopneas recorded during the study per hour of sleep. It is generally expressed as the number of events per hour. Based on the AHI, the severity of OSA is classified as follows:

None/Minimal: AHI < 5 per hour
Mild: AHI ≥ 5, but < 15 per hour
Moderate: AHI ≥ 15, but < 30 per hour
Severe: AHI ≥ 30 per hour

As far as I know, the AHI at 4cm would be the closest approximation of untreated AHI you could measure using a typical machine.

bouncer wrote:I have read in the past that it is normal for everyone to have some hypopneas. So if that is correct, if you set the machine on the lowest pressure (i e 4) does anyone know what AHI readings a person without OSA would get?

No, because everybody is different and "supposedly" anyone below a 5.0 AHI is considered to be non-apnea.
And, even a pressure of "4" has some therapeutic benefit.


Den

.

Believe it or not but some lucky people can have an AHI of 40 and see AHI of 0.0 with 4 or 5 cm pressure. Doesn't happen often but for some lucky people all that they need to hold the airway open is that little bit of pressure.

Severity of apnea in terms of number of events has no correlation with pressure needs.

Now even people who don't have even the mild diagnosis might still have an occasional event of some sort show up on a machine's report when done at 4 cm.
We would assume that it would be below the 5 per hour average needed to meet the diagnosis criteria though.
So it's normal for "normal" people, who don't meet criteria, to have a few pauses in breathing or minor collapses of the airway.
So a machine set at minimum pressure might flag those events if it happened that more pressure was needed but it is possible also that there wouldn't be any flagged events because that minimum might have prevented whatever might have happened if the machine wasn't used.

Pugsy wrote:Believe it or not but some lucky people can have an AHI of 40 and see AHI of 0.0 with 4 or 5 cm pressure. Doesn't happen often but for some lucky people all that they need to hold the airway open is that little bit of pressure.

I am one of those people, I had more events than minutes each hour but only took 5 cm to stop the apnea (they bumped to 6 to stop a couple snore events). It happens.

I have been watching this thread with interest, hoping to see someone with the same experience as I. All my life I have been a light sleeper and I have always been seriously sleep deprived. There is nothing in my life that hasn't been seriously affected by my VERY LOW AHI. Here's what I think is happening. I sleep about five hours per night and I have a 20 or 30 minute nap during the day. After two attacks I wake up. I am in a sweat and very hot. I go to the bathroom. I try to sleep again and fail. Two hours later I'm back asleep. To get five hours of sleep I waste about 8 hours. My initial AHI was 3.8. I was awake almost all the time trying to get used to the machine. When my DME gave me the results I re-calculated my AHI. I eliminated the hours that I was awake. This gave me an AHI of between 5 and 7. Now after two months on APAP I have an AHI of .3 to .7. But I am hoping for better sleep. The first attacks still wake me up. There I am at the edge of the bed assuming a "martial arts" position convince that someone is in my room. Being Canadian I used to play hockey, when I was growing up, after the first attack. This was sometimes at 1:00AM. The lake was next to our house. It still is. Sometimes I would take long walks or read all night.