Post Reply 
AHI vs RDI?
Author Message
lvillanueva5 Offline

Members

Posts: 8
Joined: Nov 2014

Machine: PR System One REMstar Auto CPAP Machine with A-Flex
Mask Type: Nasal mask
Mask Make & Model: Eson - Fisher & Paykel
Humidifier: Unsure
CPAP Pressure: 10
CPAP Software: Not using software

Other Comments:

Sex: Female
Location:

Post: #1
AHI vs RDI?
I have an AHI of 1.5 and an RDI of 18.5 and my doctor has diagnosed me with moderate OSA for which I am now on a CPAP. All the information that I've been reading focuses on the AHI and that if it's below 5, it's normal.

Do cpap machines keep track of RDIs? Is that something that will transmit to sleepyhead? (I've been reading the forum post on it.)

I guess, am I really suffering from moderate OSA if my AHI is normal. I'm not 100% happy with the doctor that I'm seeing and I'm worried that maybe he is pushing the CPAP therapy on me when it doesn't need to be.
11-11-2014 04:53 PM
Find all posts by this user Post Reply Quote this message in a reply

Donate to Apnea Board
AshSF Offline

Advisory Members

Posts: 356
Joined: Oct 2014

Machine: PRS1 D560TS
Mask Type: Nasal pillows
Mask Make & Model: ResMed P10, Bkup: Airfit F10 & Quattro Air
Humidifier: PRS1 60 series with Heated Tube
CPAP Pressure: 8 - 8 w/ Aflex 3
CPAP Software: SleepyHead

Other Comments: Using APAP mode with fixed pressure

Sex: Male
Location:

Post: #2
RE: AHI vs RDI?
Remstar Auto w/ Aflex will track RDI. You can view it in Sleepyhead s/w. You will need to go to Preferences in sleepyhead menu and change the metric from AHI to RDI. It will then display RDI instead of AHI in your stats.

Started APAP 4-20, Closed range to 7.5-14, then straight 8.0 w/ Aflex 3
RDI always below 1. But sleep much much better at straight pressure.
Started on F10, Tried Quattro Air successfully. Finally settled on P10.
11-11-2014 05:22 PM
Find all posts by this user Post Reply Quote this message in a reply
Crimson Nape Offline

Monitors

Posts: 1,332
Joined: Oct 2014

Machine: ResMed S9 Autoset
Mask Type: Other
Mask Make & Model: P-10 / F&P Simplus / DreamWear
Humidifier: H5i w/Climateline
CPAP Pressure: 8 - EPR 3
CPAP Software: SleepyHead

Other Comments: CMS-50F & 50IW

Sex: Male
Location: Georgia

Post: #3
RE: AHI vs RDI?
I'm a newbie too and hadn't known or noticed the RDI designation until you mentioned it. Upon Googling it, I found this definition:

An index used to assess the severity of sleep apnea based on the total number of complete cessations (apnea) and partial obstructions (hypopnea) of breathing occurring per hour of sleep. These pauses in breathing must last for 10 seconds and are associated with a decrease in oxygenation of the blood. In general, the RDI can be used to classify the severity of disease (mild 5-15, moderate 15-30, and severe greater than 30).

Also Known As: Respiratory Disturbance Index, Apnea-Hypopnea Index or AHI

I went back an looked at my Sleep study report, It had my AHI and RDI as the same number, 86.2. I too would like a better explanation.

My bad! Right after I posted this I came across the actual difference between the two, RDI includes respiratory-effort related arousals (RERAs).

Statistics prove that people who have more birthdays live longer.
(This post was last modified: 11-11-2014 05:39 PM by Crimson Nape.)
11-11-2014 05:34 PM
Find all posts by this user Post Reply Quote this message in a reply

Donate to Apnea Board
retired_guy Offline

Preferred Members-2

Posts: 2,744
Joined: Jan 2014

Machine: ResMed S9 Autoset
Mask Type: Nasal pillows
Mask Make & Model: Resmed Airfit P10
Humidifier: ResMed
CPAP Pressure: 10.6/14, EPR 3
CPAP Software: ResScan SleepyHead

Other Comments: Is it bedtime yet?

Sex: Male
Location: Beautiful, albeit very wet Oregon Coast

Post: #4
RE: AHI vs RDI?
I don't see anything in those numbers that would make me say you have "moderate" osa. But sometimes the numbers do not contain all the answers. So let's look to the symptoms. What about snoring? Have the neighbors constructed a sound-proof wall between your houses, and they live a quarter of a mile away? Do your cats move out at night preferring to live at the train station?

Then there's daytime sleepiness. Do you find yourself waking up in a cow pasture just south of Lincoln Nebraska when your original destination was your office in Atlanta? Do your fellow workers make caustic comments about the corn flakes on your nose where you didn't get them all washed off after falling into your breakfast?

Sometimes the apnea therapy is as much about improving quality of sleep, hence quality of life as it is about stopping any specific obstructive apnea.

But I'm suspicious with the numbers you post. So more information would be helpful please.
(This post was last modified: 11-11-2014 07:00 PM by retired_guy.)
11-11-2014 06:58 PM
Find all posts by this user Post Reply Quote this message in a reply
zonk Offline

Advisory Members

Posts: 7,908
Joined: Feb 2012

Machine: A10 AutoSet
Mask Type: Nasal mask
Mask Make & Model: Activa LT
Humidifier: Integrated /ClimateLineAir
CPAP Pressure: 9/13
CPAP Software: ResScan

Other Comments: CPAP since Nov 2010

Sex: Male
Location: Australia

Post: #5
RE: AHI vs RDI?
RDI is always than AHI as it include RERAs plus apnea and hypopnea
RERAs do not meet the scoring criteria of apnea and hypopnea but nevertheless are as worrisome as apnea and hypopnea

By using AHI alone would not qualify you for CPAP under insurance rules but RDI does

Prof Colin E. Sullivan inventor of CPAP siad the following:
Probably the best indicator of SDB, however, is simply the response to continuous positive airway pressure (CPAP) treatment. "It really is a no-brainer," Dr. Sullivan remarked, pointing out that CPAP administration is especially easy with the newer devices that automatically set the appropriate amount of positive pressure.
http://www.apneaboard.com/forums/Thread-...or-Useless
(This post was last modified: 11-11-2014 07:15 PM by zonk.)
11-11-2014 07:15 PM
Find all posts by this user Post Reply Quote this message in a reply

Donate to Apnea Board
lvillanueva5 Offline

Members

Posts: 8
Joined: Nov 2014

Machine: PR System One REMstar Auto CPAP Machine with A-Flex
Mask Type: Nasal mask
Mask Make & Model: Eson - Fisher & Paykel
Humidifier: Unsure
CPAP Pressure: 10
CPAP Software: Not using software

Other Comments:

Sex: Female
Location:

Post: #6
RE: AHI vs RDI?
(11-11-2014 06:58 PM)retired_guy Wrote:  I don't see anything in those numbers that would make me say you have "moderate" osa. But sometimes the numbers do not contain all the answers. So let's look to the symptoms. What about snoring? Have the neighbors constructed a sound-proof wall between your houses, and they live a quarter of a mile away? Do your cats move out at night preferring to live at the train station?

Then there's daytime sleepiness. Do you find yourself waking up in a cow pasture just south of Lincoln Nebraska when your original destination was your office in Atlanta? Do your fellow workers make caustic comments about the corn flakes on your nose where you didn't get them all washed off after falling into your breakfast?

Sometimes the apnea therapy is as much about improving quality of sleep, hence quality of life as it is about stopping any specific obstructive apnea.

But I'm suspicious with the numbers you post. So more information would be helpful please.

I need to download the sleepyhead software and figure that all out. I have no idea what all my numbers are, but as soon as I do, I'll post it.
(This post was last modified: 11-12-2014 08:53 AM by lvillanueva5.)
11-12-2014 08:48 AM
Find all posts by this user Post Reply Quote this message in a reply
Crimson Nape Offline

Monitors

Posts: 1,332
Joined: Oct 2014

Machine: ResMed S9 Autoset
Mask Type: Other
Mask Make & Model: P-10 / F&P Simplus / DreamWear
Humidifier: H5i w/Climateline
CPAP Pressure: 8 - EPR 3
CPAP Software: SleepyHead

Other Comments: CMS-50F & 50IW

Sex: Male
Location: Georgia

Post: #7
RE: AHI vs RDI?
lvillanueva5, The ultimate question is; "Do you feel better when you wake up?"

Statistics prove that people who have more birthdays live longer.
11-12-2014 08:54 AM
Find all posts by this user Post Reply Quote this message in a reply

Donate to Apnea Board
lvillanueva5 Offline

Members

Posts: 8
Joined: Nov 2014

Machine: PR System One REMstar Auto CPAP Machine with A-Flex
Mask Type: Nasal mask
Mask Make & Model: Eson - Fisher & Paykel
Humidifier: Unsure
CPAP Pressure: 10
CPAP Software: Not using software

Other Comments:

Sex: Female
Location:

Post: #8
RE: AHI vs RDI?
(11-12-2014 08:54 AM)sgearhart Wrote:  lvillanueva5, The ultimate question is; "Do you feel better when you wake up?"

No Sad But again, this is day 7 that I am using the cpap. I didn't have a problem sleeping on my side with the simplus mask, but as soon as I moved to my back, it felt like too much pressure.

I downloaded the sleepyhead app and imported my data. My data is:

RDI .32
Hypopnea .11
Obstuctive Apnea .00
Clear airway Apnea .21
Vibratory Snore .11
Periodic Breathing .00

Is this good?
(This post was last modified: 11-12-2014 09:11 AM by lvillanueva5.)
11-12-2014 09:11 AM
Find all posts by this user Post Reply Quote this message in a reply
Crimson Nape Offline

Monitors

Posts: 1,332
Joined: Oct 2014

Machine: ResMed S9 Autoset
Mask Type: Other
Mask Make & Model: P-10 / F&P Simplus / DreamWear
Humidifier: H5i w/Climateline
CPAP Pressure: 8 - EPR 3
CPAP Software: SleepyHead

Other Comments: CMS-50F & 50IW

Sex: Male
Location: Georgia

Post: #9
RE: AHI vs RDI?
I'm envious of your numbers. I'm down to a AHI of 2.8 and walking around like it's a birthday.

Statistics prove that people who have more birthdays live longer.
11-12-2014 09:28 AM
Find all posts by this user Post Reply Quote this message in a reply

Donate to Apnea Board
PsychoMike Offline

Advisory Members

Posts: 551
Joined: Aug 2013

Machine: ResMed S9 AutoSet
Mask Type: Other
Mask Make & Model: Varies with mood, ResMed F10 is my primary
Humidifier: ResMed H5i
CPAP Pressure: 12-17
CPAP Software: SleepyHead

Other Comments: asthma, cyclist upgraditis, just a little crazy (honest :D )

Sex: Male
Location: Alberta, Canada

Post: #10
RE: AHI vs RDI?
LV, it could be that rather than a "pure" apnea, you're more in the upper airway resistive syndrome (UARS) category like me.

In my study, I only had an AHI of 6 which would have placed me in a very mild apnea category. My RDI, on the other hand, was over 50 and considered severe. The issue is that when my airway collapsed (i.e. for an apnea event), my brain was waking up too quickly for it to score the drop in blood oxygen saturation associated with a "real" apnea event....still felt like crap in the morning from not sleeping, but not getting the AHI numbers that would traditionally explain it.

UARS is a form of obstructive sleep breathing, like apneas, but not all docs will diagnose UARS....they just lump it all into OSA and be done with it. An RDI of 18 with an AHI of 1.5, to me at least, suggests moderate UARS, which is real and just as much an issue as OSA. Sure, you don't have an 18 AHI...but for what an RDI of 18 does to your sleep, you may as well have...at its most simple level, the differences are the length of events and what's happening to your blood O2 levels.
11-13-2014 12:17 PM
Find all posts by this user Post Reply Quote this message in a reply
Post Reply 


Forum Jump:

Who's Online (Complete List)