Transcript Obstructive Sleep Apnea Updates - American Osteopathic Association

Obstructive Sleep Apnea Updates:
Prevalence, Predictors, Diagnosis
and Therapy
October 2, 2013
Tina Waters, MD
Objectives
• Describe the prevalence of obstructive
sleep apnea (OSA)
• Identify clinical features that should
prompt a suspicion for OSA
• Understand the importance of
incorporating screening tools with
testing to diagnose OSA
• Review the current therapies available
for OSA
Obstructive Sleep Apnea
(OSA)
Characterized by
recurrent episodes of
upper airway collapse
and obstruction
associated with arousals
and/or oxyhemoglobin
desaturation.
This is a
polysomnographic
(PSG) finding.
Obstructive Sleep Apnea
Syndrome (OSAS)
• When OSA is associated with daytime
symptoms, such as excessive daytime
sleepiness, it is labeled the obstructive
sleep apnea syndrome.
Obstructive Sleep Apnea
• PSG reveals > 5 obstructive events/hr on
PSG and at least 1 of the following
- Daytime sleepiness, sleep attacks,
unrefreshing sleep, fatigue or insomnia
- Waking with breath holding, gasping or
choking
- Observer reports loud snoring, breathing
interruptions or both
OR
• PSG reveals > 15 obstructive events/hr
International Classification of Sleep Disorders, 2nd ed.
American Academy of Sleep Medicine. 2005.
Sleep Apnea Severity Grading
Mild
AHI
5 -<15
Sa02 (%)
>85
EKG
Mild tachybradycardia
Moderate
15 -<30
75-85
Severe
>30
<75
Prominent tachybradycardia,
Asystole <3 sec
Asystole >3 sec, VT
Apnea-hypopnea index (AHI) - primary grading parameter
AHI = apneas + hypopneas
total sleep time (hrs)
American Academy of Sleep Medicine Task Force Sleep 1999;22:667-689
Types of Apnea
• Apnea = complete airway obstruction
• Drop in thermal sensor excursion >90% for > 10 sec
- Obstructive: Continued effort during period of absent
airflow
- Central: Absent effort during period of absent airflow
- Mixed: Absent effort initially followed by resumption
of effort
Iber C et al, AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications, 2007.
Obstructive Apneas
Hypopneas
Evolving Hypopnea Definition
• Hypopnea = partial airway obstruction
• 2007 Scoring Manual1
- Recommended: Drop in nasal pressure
excursion by >30% for >10 sec w/ >4%
desaturation
- Alternate: Drop in nasal pressure excursion by
>50% for >10 sec w/ >3% desaturation or
arousal
• 2012 Revised Scoring2
- Drop in nasal pressure excursion by >30% for
>10 sec w/ >3% desaturation or arousal
1Iber
C et al, AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications, 2007;
Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications Version 2.0, 2012.
2AASM
Impact of Hypopnea Scoring on AHI
3 recognized hypopnea definitions produce
markedly different AHIs
Ruehland WR et al. SLEEP 2009;32:150-157.
OSA
• Clinically recognized more than 40
years ago
• Awareness of this condition was slow
to develop until population based
studies were performed and uncovered
a high prevalence of OSA in adults
Guilleminault el al. Annu Rev Med 1976;27:465-484
Population-based OSA and
OSAS prevalence studies
Study
# subjects
AHI>=5
AHI >=15
OSAS Methods
WI, 1993
M=352
W=250 (age 30-60)
M=24%
W=9%
M=9%
W=4%
M=4%
W=2%
PA, 1998,
2001
M=741
W=1000
(age 20-100)
M=17%
W=5%
M=7%
W=2%
M=3.3% PSG
W=1.2%
Spain,
2001
M=325
W=235 (age 30-70)
M=26%
W=28%
M=14%
W=7%
M=3.4%
W=3%
PSG
Australia,
1995
M=294 (age 40-65)
M=25.9%
M=10%
(AHI≥10)
M=3.1%
W=n/a
HST
Hong
M=153 W=106 (age M=8.8%
Kong,
30-60)
W=3.7%
2001, 2004
M=5.3%
W=1.2%
M=4.1% PSG
W=2.1%
Korea,
2004
M=309, W=148
(age 40-69)
M=27%
W=16%
M=10.1%
W=4.7%
M=4.5% PSG or HST
W=3.2%
India, 2006
M=88 W=63 (age
30-60)
M=19.7%
W=7.4%
n/a
M=4.9% PSG
W=2.1%
PSG
Adapted from Lee et al. Expert Rev Respir Med 2008;2:349-364
Ethnicity
• Similar prevalence in Asian
populations when compared to
Western societies
- Despite lower BMI in Asians
- Could be attributed to cephalometric
differences
• Limited data on prevalence of OSA in
Hispanics
Ip et al. Chest 2001;119:62-69
Ip et al. Am J Respir Crit Care Med 2001;163:A636
Ip et al. Chest 2004;125:127-134
O’Connor et al. Sleep 2003;26:74-79
Ethnicity
• Population based studies suggest that
OSA prevalence is as high or higher in
African Americans compared with
Caucasians.
• For community dwelling African
Americans >65 years, the odds of
having severe OSA was 2.5x greater
relative to Caucasians.
Ancoli-Israel et al. Am J Respir Crit Care Med 1995;1946-1949
Ethnicity
• Cleveland Family Study:
- OSA prevalence is higher in African Americans <25 years
than Caucasians
• Other investigators reported disproportionately
higher severity of OSA in young and elderly African
Americans compared to Caucasians
• Sleep Heart Health Study:
- Similar OSA prevalence African Americans compared to
other ethnic groups
Redline. Semin Respir Crit Care Med, 1998;19:113-122
Young, Peppard, Gottlieb, Am J Respir Crit Care Med 2002
Lee et al. Expert Rev Respir Med 2008;2:349-364
Young, et al. Arch Intern Med 2002;893-900
Redline et al. Am J Respir Crit Care Med 1997;155:186-192
OSA- Women
• Differences in clinical presentation
(compared to men)
- ↓ snoring and apneas
- ↑ insomnia
- ↑ EDS and fatigue
• ↓ survival rates compared to men with
similar AHIs
Redline, et al. Am J Respir Crit Care Med 1994; 149:722-26
Collop, et al. Chest Med 2004;25:257-268
Young, et al. Thorax 1998;53(Suppl 3):S16-19
OSA-Women
• Differences in PSG features (compared to
men)
- Lower AHI (when matched for body weight)
• Less collapsibility of upper airway
- Less supine position dependency of
respiratory events
- Commonly cluster during REM sleep
O’Connor, et al. Am J Respir Crit Care Med 2000;161:1465-1472
OSA - Women
• OSA is less common in premenopausal women than in men
- Risk of OSA increases in women during
menopause
- Lower prevalence of OSA among
postmenopausal women who use HRT
compared to women not on HRT
Young et al. Am J Respir Crit Care Med 2003;167:1181-1185
Shahar et al. Am J Respir Crit Care Med 2003;167:1186-1192
OSA - Aging
• Several studies found OSA to be highly
prevalent in people >65 years
• Prevalence for moderate OSA (AHI≥15)
varies from 7- 44%
Duran, et al. Am J Respir Crit Care Med 2001;163:685-689
Bixler, et al. Am J Respir Crit Care Med 1998;157:144-148
Bixler, et al. Am J Respir Crit Care Med 2001;163:608-613
Aging
• For ages 65-95 years
- HST – 427 people
- OSA defined as an AHI ≥ 10 occurred in
70% of men and 56% of women
• 3x higher than middle age prevalence
estimates
• For ages 71-100 years - Spain cohort
- AHI ≥5: 81% men and 80% women
• 3x higher than middle age
- AHI ≥ 15: 57% men and 49% women
• 4x higher than middle age
Ancoli-Israel et al. Sleep 1991;14:486-495
Durán, et al. World Conference Space Odyssey, 2001
Aging
• MrOs Sleep Study
- AHI ≥ 15, prevalence estimate of 21.4%-26.4%
- Prevalence increased with increasing age
• 22.8% <72 years
• 30.1% >=80 years
• Cleveland Family Study
- Higher prevalence for AHI ≥ 15 if >60 years compared
with 25-60 years
- Men: 42% vs 22%; Women: 32% vs 4%
• Sleep Heart Health Study
- AHI ≥ 15, 1.7 fold higher proportion in older (60-99
years) vs younger (40-60 years)
Mehra, et al. JAGS 2007;55:1356-1364
Redline, Semin Respir Crit Care Med 1995
Young et al. Arch Intrn Med, 2002
From: Predictors of Sleep-Disordered Breathing in Community-Dwelling Adults: The Sleep Heart Health Study
Arch Intern Med. 2002;162(8):893-900. doi:10.1001/archinte.162.8.893
Figure Legend:
Smoothed plot (5-year moving average) of the prevalence of an apnea-hypopnea index (AHI) of 15 or greater by age.
Date of download: 4/11/2013
Copyright © 2012 American Medical
Association. All rights reserved.
OSA and Aging
• Risk factors
-
Increased weight
Reduced lung function
Impaired ventilatory control
Increased upper airway collapsibility
• Soft palate gets longer
• Pharyngeal fat pads increase in size
• Response of genioglosus muscle to
negative pressure stimulation diminishes
- Impaired thyroid function
- Reduced slow wave sleep
Incidence of OSA
Study
N
Years of f/u
Definition
Incidence
Wisconsin
554
4
AHI <5 to
AHI ≥ 5
10.6%
Cleveland
Family
286
5
AHI <5 to
AHI ≥ 15
15% men
8.2% women
Sleep Heart
Health
2968
5
AHI <5 to
AHI ≥ 15
11.1% men
4.9% women
Adapted from Lee et al. Expert Rev Respir Med 2008;2:349-364
Tishler et al. JAMA 2003;289:2230-2237
Peppard et al. JAMA 2000;284:3015-3021
Newman et al. Arch Intern Med 2005;165:2408-2413
OSA Progression
N
Baseline
AHI
f/u AHI
8-yr AHI
increase
95% CI for
increase
All
282
2.5
5.1
2.7 ± 8.2
(1.7, 3.6)
Women
121
1.5
3.8
2.3 ± 6.1
(1.2, 3.4)
Men
161
3.3
6.3
3.0 ± 9.4
(1.5, 4.5)
BMI<30
179
1.5
3.0
1.6 ± 5.4
(0.8, 2.3)
BMI>30
103
4.8
10.1
5.2 ± 12
(2.8, 7.7)
3.4
7.0
3.7 (1.0)
obese –
non-obese
30-45 yrs
137
1.8
3.4
1.7 ± 6.5
(0.6, 2.7)
45-60 yrs
145
3.3
6.9
3.7 ± 9.5
(2.1, 5.2)
1.5
3.5
2.0 (1.0)
Old-young
Not-habit
snore
134
1.3
2.6
1.3 ± 5.1
(0.6, 2.0)
Habit snore
148
5.5
11.8
6.3 ± 9.7
(4.1, 8.4)
4.2
9.2
5.9 (1.0)
Habit – nonhabit snore
Wisconsin Sleep Cohort
Adapted from Terry et al. Am J Respir Crit Care Med, 2002
OSA Progression
• Wisconsin Sleep Cohort
- 282 participants
- Significant increase in OSA severity
over 8 year interval
• Cleveland Family Study
- Similar trends to Wisconsin Sleep
Cohort
- After 5 years, mean AHI increased from
2.0 (SD=1.4) to 6.2 (SD=7.9)
Prevalence of OSA in
diseases
OSA defined as either AHI ≥ 10 or 15. Each bar in the figure represents an individual study.
Prevalence of OSA in
diseases - references
Netzer, et al. Ann Intern Med
1999;131:485-491
Punjabi, et al. Sleep 2000;23:471-480
Punjabi, et al.Am R Respir Crit Care
Med 2002;165:677-682
Frey, Pilcher. Obes Surg 2003;13:676683
Rasheid, et al. Obes Surg 2003;13:58-61
Worsnop, et al. Am J Respir Crit Care
Med 1998; 157:111-115
Javaheri, et al. Circulation
1998;97:2154-2159
Javaheri, et al. Ann Intern Med 1995;
122:487-492
Javaheri, et al. Int J Cardiol
2006;106:21-28
Oldenburg et al. Eur J Heart Fail
2007;9:251-257
Andreas, et al. Coron Artery Dis
1996;7:541-545
Dyken, et al. stroke 1996;27:401-407
Turkington, et al. Stroke 2002;33:20372042
Foster et al. Sleep 2005;28:A606
West, et al. Thorax 2006;61:945-950
Fogel, et al. J Clin Endocrinol Metab
2001;86:1175-1180
Vgontzas, et al. J Clin Endocrinol
Metab 2001;86:517-520
Mooe, et al. Chest 1996;109:659-663
Mooe, et al. Am J Med 1996;101:251256
Parra, et al. Am J Respir Crit Care Med
2000;161:375-380
Bassetti, et al. Stroke 2006;37:967-972
Hui, et al. Chest 2002;122:852-860
Prevalence of OSA in
diseases
• Over 80% of individuals with moderate
to severe OSA are estimated to be
undiagnosed
- Implies unaddressed risk factors for
cardiovascular diseases, stroke, and
DM-II
Young et al. Sleep 1997;20:705-6
Kapur et al. Sleep Breath 2002;6:49-54
Common Symptoms
Nighttime
Daytime
• Snoring
• Gasping/snorting
• Witnessed
apneas
• Restless Sleep
• Nocturia
• Night sweats
• Excessive daytime
sleepiness
• Fatigue
• Morning headaches
• Memory problems
• Irritability
Risk Factors
Modifiable
Non-Modifiable
• Obesity
• Medications
- opiates
- benzodiazepines
- alcohol
• Smoking
• Nasal congestion
• Gender
• Genetic
predisposition
• Race
• Aging
• Menopause
• Craniofacial
anatomy
Young et al. JAMA 2004;291:2013-2016
Anatomic Risk Factors for
OSA
• Obesity
- Increased visceral fat; parapharyngeal
fat pads
- Increased neck size
• Increased size of upper airway soft
tissue structures
- Macroglossia, elongated soft palate,
increased lateral pharyngeal walls,
adeno-tonsillar hypertrophy
Anatomic Risk Factors for
OSA
• Recessed mandible
- Retrognathia
• Nasal airway restriction
- Septal deviation
- Allergic rhinitis
- Nasal polyps
Friedman palate position
Class 1
Class 2
Class 3
Class 4
Class 1, soft palate, fauces, uvula, anterior and posterior pillars
visible Class 2, soft palate, fauces and uvula visible
Class 3, soft palate and base of uvula visible
Tsai et al AJRCCM 2003
Class 4, soft palate not visible
Mallampati et al Can Anaest Soc J, 1985
Physical Exam
Elongated Uvula and enlarged tonsils
Physical Exam
Macroglossia and tongue ridging
Retrognathia
High-arched palate and
overjet
Nasal exam
What a deal!
25 cents
Neck circumference
• Patients with OSA have significantly
increased neck circumference
compared to non-apneic snorers
• Measure at superior border of
cricothyroid membrane
• > 40 cm (15.7 inches) has been shown
to be predictive of OSA with 61%
sensitivity and 93% specificity,
regardless of sex
Katz et al. Am Rev Respir Dis 1990;141:1228-1231
Kushida et al. Ann Intern Med 1997;127:581-587
AASM Adult OSA Task Force –
Physical findings that may suggest OSA presence
• Increased neck
circumference: >17in
for men, >16in for
women
• BMI ≥ 30kg/m2
• Friedman Class III or
greater
• Nasal abnormalities
(turbinate
hypertrophy, septal
deviation, etc)
• Retrognathia
• Lateral peritonsillar
narrowing
• Macroglossia
• Tonsillar hypertrophy
• Elongated/enlarged
uvula
• High-arched/narrow
hard palate
• Overjet
Epstein et al. J Clin Sleep Med 2009;5(3)263-276
OSA screening
• In addition to history and examination,
a number of self-report screening
instruments are available to assist in
recognition of patients with suspected
OSA
• Inexpensive and time-efficient
Epworth Sleepiness Scale
• How likely are you to doze off or fall asleep in the
following situations, in contrast to feeling just tired?
• This refers to your usual way of life in recent times.
• Even if you have not done some of these things
recently try to work out how they would have
affected you.
• Use the following scale to choose the most
appropriate number for each situation:
- 0 = would never doze or sleep
- 1 = slight chance of dozing or sleeping
- 2 = moderate chance of dozing or sleeping
- 3 = high chance of dozing or sleeping
Johns Sleep 1991;14(6):540-545
Johns Sleep 1992;15:376-81
Epworth Sleepiness Scale
0 = would never doze or sleep
1 = slight chance of dozing or sleeping
2 = moderate chance of dozing or sleeping
3 = high chance of dozing or sleeping
•
•
•
•
•
•
•
•
Sitting and reading
Watching TV
Sitting inactive in a public place
Being a passenger in a motor vehicle for an hour
or more
Lying down in the afternoon
Sitting and talking to someone
Sitting quietly after lunch (no alcohol)
Stopped for a few minutes in traffic while driving
EDS and OSA
• Sleep Heart Health Study
- Significant, progressive increase in ESS
score with increasing AHI
• ESS = 7.2 (AHI<5)
• ESS = 9.3 (AHI ≥ 30)
- % subjects with excessive daytime
sleepiness increased from 21% in those
with AHI<5 to 35% in those with AHI>30
Gottlieb, et al. Am J Respir Crit Care Med 1999;159:502-507
STOP-BANG
• Developed and validated in preoperative patients
• Sensitive screening tool for OSA
Chung, et al. Anesthesiology 2008;108:812-821
STOP-BANG Questionnaire
Answer - either yes or no:
1. Do you SNORE loudly (louder than talking or loud enough
to be heard through closed doors)?
2. Do you often feel TIRED, fatigued or sleepy during the
daytime?
3. Has anyone OBSERVED you stop breathing during your
sleep?
4. Do you have or are you being treated for high blood
PRESSURE?
5. BMI more than 35?
6. AGE over 50 years?
7. NECK circumference > 15.75 inches (40cm)?
8. Male GENDER?
STOP
• ≥ 2 yes answers: High risk of OSA
• < 2 yes answers: Low risk of OSA
• Sensitivity:
- 65.6% for AHI ≥ 5
- 74.3% for AHI ≥ 15
- 79.5% for AHI ≥ 30
STOP-BANG
• ≥ = 3 yes answers: High-risk for OSA
• < 3 yes answers: Low-risk for OSA
• Sensitivity:
- 83.6% for AHI ≥ 5
- 92.9% for AHI ≥ 15
- 100% for AHI ≥ 30
Sensitivity increases from 74 to 93% using STOP-BANG
Indications for In-Lab PSG
• Sleep-related breathing disorders
- OSA, CSA, Complex SA
- Hypoventilation
- Nocturnal desaturation
• Narcolepsy and other hypersomnias
• Abnormal motor activity/behaviors in sleep
- Seizures
- Limb movements
- Parasomnias
International Classification of Sleep Disorders, 2nd ed.
American Academy of Sleep Medicine. 2005.
In-Lab PSG
•
•
•
•
Gold standard for evaluation of OSA
8-hr attended night study
Established scoring criteria
Tailored based on clinical history
- PAP, OA Titration
- Oxygen therapy
- Expanded EEG/EMG
• Aim to record NREM/REM,
supine/off-supine sleep
Iber C et al, AASM Manual for the Scoring of Sleep and Associated Events:
Rules, Terminology and Technical Specifications, 2007.
In-Lab PSG Parameters
•
•
•
•
•
•
•
•
•
•
EEG: bilateral frontal, central, occipital
EOG: bilateral outer canthi
EMG: submental and leg
ECG
Nasal-oral airflow
Thoraco-abdominal effort
Oxygen saturation
Carbon dioxide
Body position
Snore
Iber C et al, AASM Manual for the Scoring of Sleep and Associated Events:
Rules, Terminology and Technical Specifications, 2007.
Staging Sleep on PSG
Each 30 sec epoch assigned a stage allowing for identification of
state-dependency of respiratory events
Normal Adult Hypnogram
Slow wave sleep
(OSA protective)
predominates in first 1/3
REM sleep
(OSA exacerbating)
increases in last 1/3
Sleep Study Monitoring Devices
• Type 1: In-lab, attended, overnight PSG
• Type 2: Comprehensive portable, min 7 ch
- EEG, EOG, chin EMG, ECG, airflow, effort, SPO2
• Type 3: Modified portable, min 4 ch
- 2 effort channels or effort + airflow, ECG, SPO2
• Type 4: Single or dual parameter, 1-2 ch
- SPO2 or airflow
In March 2008, CMS approved CPAP coverage based on a
diagnosis of OSA by HST
Practice parameters for the use of portable monitoring devices in the investigation of suspected obstructive sleep apnea in
adults. A joint project by the AASM, ATS, and ACCP SLEEP 2003;26(7):907-913; CMS. 2008;
http://www.cms.hhs.gov/MLNMattersArticles/downloads/MM6048.pdf..
HST Indications
• 18-65 yrs of age
• High pre-test probability mod-to-severe OSA
• Absence of co-morbid sleep/medical
disorders that compromise accuracy
• Patients who otherwise could not complete
in-lab PSG due to safety, immobility or critical
illness
• May be indicated to monitor response to nonPAP therapies (oral appliances, surgery,
weight loss)
Should not be used for screening asymptomatic patients
Collop NA et al. For AASM Task Force on PM. JCSM 2007;3(7):737-747.
HST Contraindications
• Co-morbid sleep disorders
-
Central sleep apnea, Sleep hypoventilation
Periodic limb movements
Insomnia
Circadian rhythm disorders
Parasomnias
Narcolepsy
• Co-morbid medical conditions
- Mod-severe Heart failure
• LVEF <45, pulmonary edema, NYHA class III or IV
- Other mod-severe cardiac disease
- Symptomatic neurological disease
• Neuromuscular, PD, active epilepsy, stroke
- Mod-severe pulmonary diseases
• Use nocturnal O2, resting wake PO2< 60 or PCO2> 45
Collop NA et al. For AASM Task Force on PM. JCSM 2007;3(7):737-747.
HST Methodology
• 4-7 channel devices including
airflow (thermal & nasal pressure),
effort (inductive plethysmography)
& oximetry
• Tech applies sensors/directly
educates patient
• Raw data display w/editing &
manual scoring
Raw data review by sleep
specialist
• AHI based on recording time
-> underestimates AHI
• Follow-up to review results
Collop NA et al. For AASM Task Force on PM. JCSM 2007;3(7):737-747;
CMS. 2008; http://www.cms.hhs.gov/MLNMattersArticles/downloads/MM6048.pdf..
The HomePAP Study
RCT comparing HST/Auto-PAP titration & In-lab PSG/CPAP
titration for high probability mod-to-severe OSA
(adjusted neck circumference >43 cm and ESS score >12)
Rosen CL et al. SLEEP 2012;35:757-767.
HomePAP Results
• Only 53% of subjects eligible w/AHI >15
• At 3 mo, nightly PAP use greater (4.7+2.1 vs.
3.7+2.4 hr) & PAP adherence higher (63+29
vs. 49+36 %nights) in Home vs. Lab arm
• Significant improvements within groups in
all outcomes* w/PAP therapy
• Similar PAP acceptance (93 vs. 94%), time to
treatment, outcomes* between groups
* Included Epworth Sleepiness Scale, Functional Outcomes of Sleep Quality
(FOSQ),Sleep Apnea Quality of Life Instrument (SAQLI), SF 36
Rosen CL et al. SLEEP 2012;35:757-767.
What about Split Night Studies?
• Diagnostic PSG (2 hr) followed by PAP
titration if criteria met
• AASM recommends split for AHI >401
• Position & state dependency of events
often precludes splitting
• Providers may request split at lower
cutoff (i.e. AHI >15)
1Chesson
AL et al. SLEEP 1997;20:406-422.
Nocturnal Oximetry as an OSA
Screening Tool?
• Type 4 study- doesn’t identify respiratory
events or confirm sleep
• Lacks specificity & sensitivity
• Excessive false positives
Chesson AL et al. SLEEP 1997;20:406-422; Epstein L et al. Chest 1998;113:97-103.
In-lab PSG vs. HST
Which Procedure is Right?
• In newly presenting patients w/ OSA
symptoms, two main questions should
be considered:
- How severe is the patient’s OSA likely to
be?
- Does the patient have a medical condition
or co-morbid sleep disorder that would
make HST unsafe, misleading or
substantially incomplete?
Decision Tree for Mod-to-Severe OSA
Does pt have
high pre-test
prob of modsevere OSA?
Evaluate for other sleep
disorders; consider in-lab
PSG
N
Y
Does pt have
signs/symptoms of
co-morbid medical
disorders?
Y
N
N
Does pt have
signs/symptoms
of co-morbid
sleep disorders?
N
Y
OSA
diagnosed?
In-lab PSG
Y
N
Sleep study
PM or in-lab PSG
PM
PM: Portable monitoring
OSA
diagnosed?
Y
Treatment
Adapted from Collop NA et al. For AASM Task Force on PM. JCSM 2007;3(7):737-747.
Limitations of Testing for OSA
• First night effect – sleep architecture changes
induced by artificial environment
- Prolonged sleep & REM latency
- Increased light sleep, arousals & awakenings
- Reduced REM & deep NREM (stage N3) sleep
• Night-to-night variability esp. for milder cases
• Stage & position dependent OSA
- Reduced detection on in-lab PSG
- May miss entirely on HST
OSA
Nasal CPAP
Pathophysiology of OSA
The Starling resistor offers a
pathophysiology of obstructive sleep
apnea, based on collapsibility of the
airway, and which can be reversed by
positive airway pressure therapy.
The Starling resistor model
The pharyngeal airway is represented as a collapsible segment
between rigid nasal and tracheal segments.
OSA
Nasal CPAP
Overview of OSA
Treatment
Before CPAP
CPAP 5 cmH2O
Effective Troubleshooting
Outcomes
Pressure tolerance
Humidification
Interface
Follow up
Orientation
Compliance Data
% days use
100
95
90
85
80
75
70
65
60
95.2
92.9
90.5
85.4
2 weeks
Sin et al. Chest 2002
4 week
3 month
6 month
Oral Appliances
• 52% of patients treated with OA reduce
their AHI to < 10 per hour
• Favorable effects on sleepiness and
quality of life were demonstrated
• Improvements in other neurocognitive
outcomes were not consistent
• OA less efficacious in reducing the AHI
• OA may have better compliance and are
usually preferred over CPAP
Ferguson et al. SLEEP 2006;29(2):244-262
Adjustable OA vs CPAP
• 70.3%, 47.6%, and 41.4% of patients with mild,
moderate, and severe disease achieved an AHI <
5 respectively with an aOA
• 70.1% achieved an AHI < 5 using CPAP compared
with 51.6% for an aOA (P < .001)
• aOA is comparable to CPAP for mild OSA
• CPAP is superior for moderate to severe OSA
• On multivariate analysis, a lower AHI was the only
predictor of a successful aOA titration
Holley et al. CHEST 2011; 140(6):1511–1516
Surgery in OSA
Caples, Rowley et al. Sleep 2010;33:1396-407.
Surgery
• UPPP rarely achieves a surgical cure
• 50% of UPPP have a 50% reduction in
AHI
• Hard to assess candidates for the
procedure
• UPPP may decrease future adherence to
CPAP
Khan et al. Mayo Clin Proc 2009; 84:795
Aboussouan et al. Chest 1995;107:946-51
Maxillomandibular
advancement
www.sleepapneasurgery.com
Substantial and consistent
reductions in AHI with MMA
Caples, Rowley et al. Sleep 2010;33:1396-407.
Conclusion
• OSA is characterized by repeated
episodes of complete or partial
obstruction of the upper airway during
sleep
• OSA syndrome prevalence is 4% in men
and 2% in women across geographical
regions and ethnic groups
• A simple upper airway exam and quick
validated screening tools can be used
to aid in the diagnosis of OSA
Conclusion
• In-lab PSG is recommended for most sleep
disorders including OSA in presence of comorbid sleep/medical disorders
• HST is a confirmatory test for adults 18-65
yr w/ high pre-test probability of mod-tosevere OSA without co-morbidities
• HST is not recommended for screening
asymptomatic populations
• OSA therapy options include PAP, oral
appliances and surgery