Posted by Captin Cannuck on September 11, 2008 at 15:13:49:In Reply to: CPAP Statistics question posted by oakville28 on September 08, 2008 at 04:45:33:
The fact that you looked at the daily and not weekly or monthly statistics is very important. One night is not long enough to really know anything. With more time, the real picture reveals itself. For example, lets say during the first hour, I had 20 apneas while using CPAP. I wake up and check my results, and it tells me that my AHI is 20. If I went back to sleep for another hour and during hour number two, I had only ten apneas, then I woke up and checked the results, the AHI stat would go down to (20=10/2=15) an AHI of 15. If I did the same after hour three, then (20+10=10/3=13). Now I am down to an AHI of 13... So you see, the more the number of hours, the more accurate the AHI stat. Sometimes you can get unusual results due to congestion. Do you have a cold or stuffy nose etc.? Those could be an important conditions that can have a major bearing on the results. Also, if pressure is too high, you can get central apneas. Pressure has to be just right to achieve optimum results (not too high, not too low).
To answer your numbers are high. In the book "The Promise Of Sleep", there is a good discussion of the severity of AHI as it relates to the AHI scale. Here iw what William Dement, who is the co-founder (along with Dr. Christian Guilleminault) of the AHI scale said on that:
"In 1973 Christian Guilleminault and I proposed the measure that is still used for the clinical definition of sleep apnea and for rating its severity. We called it the Apnea/Hyponea Index (AHI). Hyponea is the term we use when the throat doesn't quite close entirely, but air flow is reduced sufficiently to lower oxygen and cause an arousal. The AHI score represents the average number of Apnea and Hyponea eposodes that a patient has during an hour of sleep. We decided that an AHI of 5 should be the lower limit for making a diagnosis of apnea, so a score of less than 5 (breathing stops fewer than 5 times per hour) is considered too low for clinical diagnosis and doesn't require treatment. However treatment may be necessary if a patient has an AHI of 5 yo 10 with other signs or symptoms of apnea sucha s daytime fatigue or high blood pressure. Although not all my colleagues agree, I feel strongly that people with an AHI of 10 to 20 should definately consider treatement, even if they are not feeling sleepy during the day. In my opinion, anyone with a score over 20 should always be treated - they will soon have a serious, life-threatening problem." (Passage from Willian C. Dement, The Promise of Sleep - pg. 174).