sensors back to basics · 2018-07-19 · disclosure richard a. bonato, ph.d., m.a., rpsgt ceo and...

DISCLOSURE

Richard A. Bonato, Ph.D., M.A., RPSGT

CEO and Co-Founder of BRAEBON® Medical Corporation

Has been involved in the study of sleep and its disorders since

1986, has taught courses on Sleeping & Dreaming at Carleton

University, was the director of a sleep disorders laboratory, and

has been an author, co-author, reviewer, and examiner in

various educational organizations within the sleep field,

including the AASM, AAST, BRPT, and has served on the

Executive of the Canadian Sleep Society.

BRAEBON manufactures and sells wearable sleep sensors,

home apnea recorders, and a micro-recorder, DentiTrac, for

tracking oral appliance compliance.

Copyright 2017 BRAEBON

Oral Appliance Therapy for OSA

and Measuring Compliance in

Custom Oral Devices for OSA


Objectives

• How does OAT (and CPAP) work and how do

you know it is working?

• Compliance and why measure it?

• Test Treat Trac®

• Technology: understanding what to use

• Types of patients who may benefit from oral

appliance compliance measurement

• Evaluation of oral appliance success:

compliance reporting


iOS & Droid App – Free Dental Sleep Study Guide

Sleep Disordered Breathing Spectrum


Two key questions for DSM:

1. How does OAT work, how do you

know oral appliance therapy (OAT) is

working for an apnea patient?

2. How do you know if a patient is

wearing their oral appliance?

Change….

• Omnipresent

• Very difficult for many people

• Technology change (Test. Treat. Trac.)

• What was life like in the year 1900?

• What was the environmental crisis of

the day?

Technology we use…..

Lab (PSG) vs home (HSAT)

Type 1 PSG Type 2 HST Type 3 HSAT Type 4 HSAT

Sleep Tech in

Sleep Lab

No Tech, Home

(MediPalm/Byte)

No Tech

Home (MediByte)

No Tech,

Home (Oximeter)

16 or more

channels: EEG,

EOG, EMG, EKG,

Legs

7 or more: EEG,

EOG, EMG

4 or more 1 or 2

Thermal airflow,

Pressure airflow,

Ventilatory effort,

Snoring, Body Pos

Thermal airflow,

Pressure airflow,

Ventilatory effort,

Snoring, Body Pos

Thermal airflow,

Pressure airflow,

Ventilatory effort,

Snoring, Body Pos

Perhaps pressure

airflow

SpO2 SpO2 SpO2 SpO2

SCOPER Scale: Collop et al. 2011

Polysomnogram = PSG (full PSG or full poly)

1989: >200 lbs; 6’ high

Full Polysomnograpy (Type 1)

2003: ½ lb; 4.75” x 2.75” x 0.75” (L x W x H)

Polysomnogram = multiple sleep graph recording

EEG EOG

Chin EMG

Legs EMG

SpO2

Chest effort

Abdominal effort

EKG

Body Position

Airflow

Type 1

With in-lab PSG (Type 1)….

• We can evaluate virtually all sleep

disorders (about 90)

• Plus MSLT & MWT

• But PSG is NOT a gold standard for OSA

• There is no anatomical or biological

gold standard for OSA

• Best at the time and we got stuck with it

Home sleep apnea testing (HSAT): Type 2 / 3

2006: 93 grams; 2.75” x 2” x 0.70”

Type 2 Home Sleep Recording

Type 2: EEG, EOG, EMG + cardiopulmonary

Unambiguous Stage REM sleep….

Type 1 or Type 2

EEG During sleep stages

Beta = 16 to 30 Hz EEG

Gamma = > 30 Hz EEG

CNV & DC Potentials

Alpha EEG = 8 to 12 Hz

Theta EEG = 4 to 8 Hz

Delta EEG = 0.5 to 4 Hz

Sleep Spindle = 12 to 14 Hz

NREM REM Sleep Cycle

Copyright 2011 Braebon

OSA SNORING EKG BRUXISM

Different tests are easily configured:

bruxism, EKG, snoring, PLMs (legs), etc.


ORAL CPAP PAP INDUCED

APPLIANCE AUTOPAP PLMS

Different therapies can be monitored.


Simultaneously record:

1. EEG

2. EOG

3. EMG

4. EKG

5. Snore

6. Pressure Airflow

7. Flow Limitation

8. Thermal Airflow

9. Chest Effort

10. Abdominal Effort

11. Sum

12. SpO2

13. Pulse Rate

14. Body Position

15. *PPG (Photoplethysmogram)

16. User Events

HSAT Type 3 simpler cardiopulmonary recorder

2008: 91 grams; 2.75” x 2” x 0.70”

BRAEB

ON

Type 3 but with fewer channels



1. Snore

2. Pressure Airflow

3. Flow Limitation

4. Chest Effort

5. SpO2

6. Pulse Rate

7. Body Position


9. User Events

Type 4: overnight pulse oximetry

Type 4: Pulse Oximetry (+ more?)


1. Snore

2. Pressure Airflow

3. Flow Limitation

4. SpO2

5. Pulse Rate


DentiTrac micro-recorder

2015: 5 grams; ~12 x 11 x 5 mm

What do these devices have in common?

• They are ALL recorders

What do we do with this info?

• SDB: AHI is often focus

• Why?

• Other measures: Arousals, RDI, flow

limitation, RERAs, PRV, etc.

• Goal is successful treatment: CPAP or

OAT

How does CPAP work?

• A CPAP machine blows room air into

your airway so it doesn't collapse when

you breathe in.

• Interface covers nose (maybe mouth,

but nose better)

• Think of CPAP as an air splint

• Effective but usually low compliance

CPAP (cont’d)

• Bedside blower size is usually not an

issue for people

• Blowers are getting smaller for easier

travel: Travel PAP

• Mask interfaces remain the largest

issue for most people

How does OAT work?

• A device is placed in the mouth and

holds the mandible and / or tongue

forward, usually with increased vertical

opening, which acts as a mechanical

splint to increase airway space so your

airway doesn’t collapse (as much) when

you breathe in

• TRD vs MRD

How does OAT work?

• Custom usually better than boil & bite

• Titratable usually better than non

• Bite registration?

• Phonetic

• George Gauge

86% increase

in anterior-

posterior

area

How does OAT compare to CPAP?

Chan & Cistulli, 2009

Are you better off using something

that works well (i.e., CPAP with AHI &

PSG measures) but using it less OR

are you better off using something

that does not work quite as well (i.e.,

OAT) but using it more?


Amer J Resp Crit Care Med 2013


• Measured cardiovascular (24-h blood

pressure, arterial stiffness), subjective

sleepiness, driving simulator

performance, and quality of life

(Functional Outcomes of Sleep

Questionnaire-36)

• Randomly assigned 126 (108

completed) patients with moderate to

severe OSA


What This Study Adds to the Field

In the short term, health outcomes in patients with moderate

to severe OSA were similar after treatment with

CPAP and MAD. This was likely explained by the greater

efficacy of CPAP being offset by inferior compliance relative

to MAD. These findings strongly challenge current

practice parameters recommending MAD treatment be

considered only in patients with mild to moderate OSA.

Long-term comparative effectiveness studies between

CPAP and MAD that include objectively measured treatment

compliance are needed to better define treatment

strategies for patients with OSA.

CPAP reduced AHI better, but moderate to

severe OSA patients were similar after

treatment with CPAP and oral appliance.

Because patients wear oral appliances

more than they wear CPAP.

Long-term studies needed to compare

CPAP and MAD using objective

compliance measurement [e.g., DentiTrac].


• Why did Philips et al (2013) find this?

• “Mean Disease Alleviation” (later)


• Q/ How do you know if CPAP Tx is

working for the patient?


Pt with Hx of MI, TIA….


• Q/ How do you know if OA Tx is

working for the patient?


Before: AHI 9.5 After: AHI 11.2


Before: AHI 9.5

After: AHI 11.2 Patient feels better now

Pulse Rate Variability from 60 to 120

Overall AHI / RDI = 15.7 / 24.2

But supine this person falls into mild….

Follow-up: Baseline vs OAT Tx

16.3

3.8

CPAP Noncompliant patient using temp appliance (in a tent)

38

11

72

6



• We’ve talked about technology, we’ve

talked about how CPAP & OAT work,

how to measure their success

• How do you actually know if people

are actually complying or adhering to

treatment?

What is compliance?

• “Extent to which a person’s behavior (taking

meds, following a diet) coincides with medical

or health advice” (Haynes et al., 1979)

• Also, adherence, concordance or cooperation

(not passive terms, suggest more choice, etc.)

• For dental sleep medicine or orthodontics:

extent to which the person is using prescribed

therapy


Direct or Indirect compliance measurement

• Direct:

• Use physiological measures (airflow, body temp)

• Less subject to bias

• This is where CPAP has been

• Indirect:

• Self-reports are more frequently used and easier

• More subject to bias

• This is where OAT has been


Why is it important to measure?

• Better compliance = better results: reduced

treatment time (ortho)

• Noncompliance = waste of resources =

insurance payers will no longer pay (CPAP)


Achilles heel of CPAP = compliance

CPAP Achilles heel: compliance

• mask is a huge issue

• not size of blower

• not humidity

• not hose


Two Achilles heels of OAT

1. Objective compliance

measurement

2. A priori determination of

successful OAT candidate

Definition of compliance: CPAP

• To qualify to retain funding for CPAP after an

initial 3-month trial, a patient must

demonstrate “continued use of CPAP therapy”:

• > 4 hrs per night for > 70% of all nights

during a 30-day period of the initial 90-day

trial

• Historical def’n is >4 hrs nightly five

nights per week


Europe

Qualifying for continued CPAP funding

• France: > 3 hrs per night 7 days per week

• Germany: > 4 hrs per night

• Italy: > 3 hours per night

• Spain: > 5 hours per night

Which definition is more correct?


CPAP machines & the luxury of size


A CPAP report…..


AHI, Pressure (cm H20), leak, hours of use


Let me tell you about our patient Juan…

• Juan is from Columbia

• Juan is a bit of a round individual

• Juan has a BMI of 32.5


• Mallampati score of 0 (or less)

• Weight = 1.36kg and Height = 8”

Meet Juan….


Juan needs CPAP @ 11 cmH20


Gaming CPAP compliance

• Quick & dirty demonstration of CPAP

compliance deception:

• Cannot guarantee that it is actually

that patient wearing that particular

CPAP

• Could be bedpartner or a simple or

more sophisticated simulation

• This has important implications for the

future

CPAP Compliance / Intolerance

• When adherence is defined as greater than 4

hours of nightly use, 46 to 83% of patients with

obstructive sleep apnea have been reported to

be nonadherent to treatment.

Weaver & Grunstein (2008). Proc Am Thorac Soc Vol 5. pp

173–178, 2008

• CPAP Intolerance is a large target market for

dentists


CPAP is state of the art treatment but…

After about a year 50% of people

stop using it



Kribbs, Pack, Kline, Getsy, Schuett, Henry,

Maislin, Dinges. Effects of one night without

nasal CPAP treatment on sleep and sleepiness

in patients with obstructive sleep apnea.

Am Rev Respir Dis 1993;147:1162–1168.

Sleeping without CPAP for one night

reversed virtually all of the sleep and

daytime alertness gains derived from

sleeping with CPAP.

AASM OA Practice Parameters: 2005

• Adherence data for OAs mostly relies on

subjective reports.

• In contrast, CPAP compliance is

routinely monitored objectively.

• Development of similar capabilities for

OA therapy should be pursued for both

research and clinical purposes.

What about OAT compliance measurement?


Two Achilles heels of OAT

1. Objective compliance

measurement

What is OAT compliance?

1. How compliant are you everyday?

2. How compliant are you on days you are

wearing it for at least 15 min?

3. How compliant are you > 4 hrs daily for 5

out of 7 days for the entire data collection

period? (historical CPAP def’n)

4. How compliant are you > 4 hrs daily during

a 30-day period of the initial 90-day usage?

(this is the new CPAP def’n)


4. How compliant are you if you changed

appliances and now have a new one

(i.e., more than one)?

5. How compliant are you since the last

time we looked (uploaded) at the data?

What is OAT compliance? (cont’d)

• Headgear timer: miniature electronic watch with memory

• Pts increased wearing time when told about monitoring.

• Hours increased from 35-50 / week to 100 / week.

Northcutt, M. E. The timing headgear. J. Clin. Orthod.

V.8, p.321-324, Jun. 1974.

• Timing headgear neckband and timer

• Timing headgear readout monitor

• Neckband placed on monitor for readout

Orthokinetics: Compliance Science System

• Objectively inform orthodontists and patients the

number of hours the headgear is being worn

• Compliance Science System in 46 patients (blind)

• After two months two groups set up:

• uncooperative <16 hrs daily now informed of monitor

• cooperative > 16 hrs daily remain blind to monitor

• 4 months later: statistically significant increase in

usage in the uncooperative group

Creative children found a way around it….

Temperature sensor with periodic sampling


What is an OAT compliance

monitor (DentiTrac)?

Is it a sensor? NO

Is it a chip? NO

Is it a micro-recorder? YES


Both are dataloggers (recorders)


Having a lab embed a recorder into an appliance

is as simple as inserting a label…

•We anticipate most dentists will

check a box when ordering the

appliance


Auxilary can do much of this:

• Data is read by the base station and

uploaded to the cloud portal for analysis

and reporting

• Reading data is as simple as placing the

OA into the base station


DentiTrac processed data

2. CWhenWorn = 91%

1. Ceveryday = 87%

3. C5 of 7 = 95%

4. C90 = 100%


CPAP compliance &

OAT compliance data


CPAP & OAT Compliance Data Detailed View

Pearson r = 0.92, r2 = .85; t-test = NS

Definition of compliance: OAT


Vanderveken et al. 2013: Thorax

• Objective compliance measurement &

OAT

• Compared objective and subjective OAT

compliance

• Introduced “mean disease alleviation”

Vanderveken et al. 2013

• Objective OAT compliance measurement

allows calculation of mean disease

alleviation, defined as a combined function of

efficacy and compliance, being a measure of

overall therapeutic effectiveness

• Effectiveness = compliance x efficacy.

• OA efficacy (%) = baseline AHI minus

AHI with OA (e.g., 10 – 4.4 = 56%)

• Mean Disease Alleviation = product of

adjusted compliance (worn 91.2% of the

time) with therapeutic OA efficacy (56%

above = 51.1%


Mean disease alleviation

CPAP example…

• If the AHI on CPAP drops from 50 to 2

then it is a 96% reduction

• If the patient only wears the CPAP 50%

of the time then Mean Disease

Alleviation = 50% x 96% = 48%

• Higher compliance with OAT = similar

adjusted effectiveness as compared

with CPAP

• OAT is not as good as CPAP in

reducing AHI, but MDA values might be

comparable with CPAP because of the

higher compliance with OA therapy (and

that’s what Philips et al. 2013 said too)


More research using objective OA compliance…

51 patients with mild to moderate OSA

Dieltjens et al. 2015 JAMA Oto Head & Neck

• Neither anthropometric & polysomnographic

parameters nor reports of excessive daytime

sleepiness correlated with OAT compliance

• Two parameters which correlated with higher

OAT objective compliance were decreased

snoring and dry mouth

Journal Dental Sleep Medicine: 2015

CPAP & OAT have limitations: CPAP Tx often

has low patient acceptance, poor tolerance and

suboptimal compliance; OAT usually has inferior

PSG efficacy when compared to CPAP

According to MDA concept….

• OSA Tx with CPAP, OAT or other non-

CPAP modalities, as a single treatment,

usually means incomplete elimination of

the disorder with average MDA index,

as a marker of real clinical

effectiveness, ranging from 40 to 59%

Vanderveken 2015….

• Greater CPAP efficacy is offset by its

inferior compliance relative to OAT

• This is not imaginary, and results in a

similar overall effectiveness for both

therapeutic modalities

• Mandibular advancement + tongue

protrusion = effective treatment for

moderate-to-severe OSA: tongue bulb

added to MRD provides further

therapeutic effectiveness.

Vanderveken 2015: Combo Tx

Dort & Remmers

JCSM 2012

• OAT + multilevel upper airway surgery

• OAT + positional Tx

• Recent study reported MDA increased

from 42% to 70% when OAT was

combined with positional Tx

(Dieltjens et al., 2014)

Vanderveken 2015: Combo Tx

But can we game OAT same as CPAP?

• It is much more difficult to deceive OAT

with DentiTrac objective compliance

than to deceive CPAP with Juan

• My OA won’t fit my bedpartner

• My dog luvs my OA as a chew toy

• Juan is not a substitute

• What about a heated water bath?


• Bϋchi heating bath deception

• 2 litres of water warmed to 35 C (95 F)

between 2100 and 0700 to simulate wearing

• Off 0700 to 1400

• On again 1400 to 1600 and 1700 to 1900

• Off 1900 to 2100

• Thus, total of 14 hrs wearing & 10 non-

wearing every 24 hours

Schott & Goz, Journal of Orofacial

Orthopedics, 2010, 79, pp 339-347.


With a simple temp measurement device,

they concluded that the warm water

bath could deceive the temperature

sensing technology and report wearing

when not actually worn

The DentiTrac was not susceptible to

this deception because more than

temperature is being recorded and

anti-deception algorithms are

implemented

To conclude:

• Exciting times for OA Tx

• OAT compliance measurement is a

rapidly expanding frontier of dental

sleep medicine

• New standards evolving

• Modeled after the existing CPAP

compliance paradigm

• Test. Treat. Trac.®

Where to go from here?

• Principles & Practice of Sleep Medicine (6th Ed)

• ASBA Diplomate Exam


Thank you!

[email protected]

sensors back to basics · 2018-07-19 · disclosure richard a. bonato, ph.d., m.a., rpsgt ceo and...

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