Portable Testing for Sleep Disorders

How to do it

When to use it

Pittsburgh Mind Body Center, Core D“The Pittsburgh Sleep Group (PSG)”

Sleep Testing Possibilities

Questionnaires Actigraphy Full PSG Other

Portable Testing

What we will cover in this sessionRationaleTypes of equipmentPros and cons of different systemsCostsExamples of usage; some hands on “play”Questions/Answers

Portable Sleep Apnea Monitoring

Current State of non-Sleep Laboratory Diagnosis of OSA

Clinical suspicionProbably accurate in obvious cases but cannot be

routinely relied uponLacks sensitivity and specificity

QuestionnairesValidate clinical suspicionNone sufficiently sensitive or specific as a stand alone

diagnostic methodAre useful as an adjunct to clinical decision-making,

triage – MAP, Berlin are reasonable to consider

Cardiovascular Consequences of Sleep-Disordered BreathingReport of a Workshop From the National Center on Sleep Disorders

Research and the National Heart, Lung, and Blood Institute

Circulation 2004109:951-957

Basic Science Clinical Epidemiology

Clinical Therapeutic Studies

SleepDisordered Breathing

&Cardiovascular

Disease

Cellular / molecularstudies

Mouse models

Pathway studiesfor humans

• High – risk patient subsets• Development of new treatment approaches

Develop new tools for

population screening

Prospective cohort studies

Incorporation of SDB / Sleep Deprivationin ongoing CV cohort studies

Institute of Medicine Report2006

What is needed? Expand awareness

among health care professionals through education and training.

Develop and validate new and existing diagnostic and therapeutic technologies.

Ability of type III monitors in the home setting to identify AHI suggestive of OSAHS in laboratory-based

polysomnography

Pos LR >10

Neg LR < 0.1

From Trikalinos et al, AHRQ, 07

Current State of non-Sleep Laboratory Diagnosis of OSA

Diagnostic equipment • Terminology: Portable, ambulatory, out-

of-sleep lab, HST, etc

• Types of equipmentType 2Type 3Type 4

Type 2 Monitors: Mini-PSG

Advantage• Multiple channels• Flexibility of signal

type• Comprehensive• Use standard software

of a base system• Portability• Extensive track-record

in research applications

Disadvantage• Tech hook up • Expensive• Probably no

reimbursement for home PSG

• Loss of signal – no way to easily correct problem

Type 3 Monitors: Cardio-pulmonary Studies

Advantage• Easy to set up: easily

done by most patients; technician not required

• Inexpensive (<$10K)• Very portable• Reduced number of

signals

Disadvantage• Reduced number of

signals• No reimbursement• Signal loss at home;

not way to correct• Requires scoring or at

least overview of scoring by tech; takes longer than you think

Type 4 Monitors: Oximetry +

Advantage• Most portable• Inexpensive• Easy to set up• Core signals:

oxygenation and airflow

• Now may include PAT signal

Disadvantage• No reimbursement• Minimal number of

signals – may not capture important aspects of some OSA

• Signal loss

Current Uncertainties: Type 3 & 4 Devices

How many signals are needed? Which signals add the most value? Are there clinical populations that this

does not work in? How can technology be combined with

clinical decision making to optimize OSA diagnosis outside the sleep lab?

More uncertainties…

New technologies – how do they fit in to the existing PSAT device classification?• WatchPAT-100• PTT• ARES• New systems on the horizon will have

capabilities to be a level 2-4 by adding or taking away modules

Stardust

Made by Respironics, Inc Level 3 device Measures: airflow, resp. effort, oximetry,

heart rate, body position Well validated Moderately expensive, ~$7000 but

subsequent units are cheaper Moderate tech time for scoring

Embletta

Somnologica/Medcare Level 3 Measures: Airflow, respiratory effort,

oximetry, body position Well-validated, widely used Moderately expensive, similar to Stardust Moderate tech time for scoring

Type 3 monitor

Type 3 monitor

Stardust Report

Apnea link

Resmed, Inc. Level 4 Measures: airflow +/- oximetry Some validation; generally shows that it’s

accurate in detecting more severe OSA Relatively inexpensive; consumables less

than $15 for earlier models Limited tech time

Example of moderate sleep apnea on Apnea Link

WatchPAT

Works on principle of changes in peripheral arterial tonometry

Indirect measure of ANS activity PAT is a surrogate marker for apnea,

hypoxia Moderately expensive to purchase;

individual probes are recurring cost Minimal to no tech time for scoring

WatchPAT Example

Other devices

Apnea Risk Evaluation System (ARES)• New unit• Cardiopulmonary

monitor• Moderately expensive• Some local experience

with it• Tech time minimal

Night Cap

Developed by Dr. Allan Hobson Head cap that can measure NREM vs.

REM sleep Limited validation studies Not used much anymore as best as I can

tell ?Commercial availability

Bodymedia -Sensewear

Bodymedia, Inc Wearable devices

that sense activity – more akin to actigraphy

Evolving more into a obesity management solution than a sleep rhythm detector

Scenario 1

Your objective is to measure psychological “well-being” in a cohort of Iraq war veterans over a 3 year span beginning with the end of military service

You are concerned that sleep disorders will be a mediator of psychological health

Your are also concerned that sleep disorders will confound the sleep measure

Scenario 1, continued

Your budget is very limited How can you assess for sleep apnea in a

cost efficient way? How can other sleep disorders be

assessed? What tools would you use and why?

Scenario 2

Your objective is to screen a population of factory workers for sleep apnea as part of a wellness program you are consulted about

You have 2500 middle-aged men and women to screen

Your budget total budget for sleep screening is $20 per person but you can get some equipment through a different grant

Scenario 2, continued

How would you screen for sleep apnea? What are the pros and cons? What else do you need to know?

Scenario 3

Your objective is to measure sleep and rule out sleep apnea in a study of obese individuals contemplating bariatric surgery and stress

This is a pilot study and you have essentially no budget but you have friend who will help with the sleep part for free (within reason).

Scenario 3, continued

What would your approach be? How might you combine approaches?

Further reading

http://www.cms.hhs.gov/mcd/viewtechassess.asp?from2=viewtechassess.asp&where=index&tid=48&

Or, go to www.ahrq.gov and search for completed technology assesments in 2007