Transcript So Who Should Get a Sleep Study

Sleep Medicine
Something Old / Something New
Glenn W. Burris, MD, MS, FAASM
Medical Director
The SOMC Sleep Diagnostic Center
Portsmouth, Ohio
Learning Objectives
1.
The learner will understand the basic components of a diagnostic
polysomnogram and the speaker will explain the definitions of
respiratory events used to calculate the Apnea-Hypopnea Index.
2.
The speaker will present clinical guidelines for the use of
unattended portable monitors in the diagnosis of obstructive sleep
apnea
3.
The learner will understand some of the health benefits of treating
obstructive sleep apnea with nasal CPAP.
The Study of Sleep
1834 – Robert McNish
“ Sleep is the intermediate state between wakefulness
and death, wakefulness being regarded as the
active state of all the animal and intellectual
functions, and death as that of their total
suspension.”
The Study of Sleep
1937 – Davis, Loomis, Harvey, Hobart - different stages of sleep were
reflected in changes of the EEG
1953 – Asereinsky & Kleitman -Identification of Rapid Eye Movements
during Sleep
1957 – Dement & Kleitman - Relationship between eye movements,
body motility, and dreaming
1968 – Rechtschaffen and Kales (R&K) - standard sleep scoring
technique
2007 – American Academy of Sleep Medicine - Manual for the Scoring
of Sleep and Associated Events
Polysomnogram
Continuous monitoring of physiology during sleep
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Electroencephalogram (EEG)
Eye Movements
Nasal and Oral Air flow
Submental Muscle activity (EMG)
Respiratory Effort – Chest and Abdomen
Cardiac Rhythm
Leg Muscle Activity – tibialis anterior
Pulse oximetry
Snore Microphone
Video Monitoring
Polysomnogram
Information is included in 30 second epochs
Polysomnogram
Following completion of the study the information is scored:
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Lights out
Sleep Latency – from lights out to onset of sleep
Sleep Stages
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Non-REM – N1, N2, N3
REM
Sleep Efficiency – percentage of time asleep
Respiratory Events
Leg Movements
Arousals
Heart Rhythms
Snoring intensity
Lights on
Quality of patient’s sleep compared to baseline
Scoring Respiratory Events
Apnea – when all of the following criteria are met
1)
2)
3)
4)
There is a drop in the peak thermal sensor excursion by >90% of
baseline
The duration of the event lasts at least 10 seconds
At least 90% of the event’s duration meets the amplitude criteria for
apnea
Classified as: obstructive, central, or mixed based on respiratory effort
Hypopnea – when all of the following are met
1)
2)
3)
4)
The nasal pressure signal excursion drops by 30% of baseline
The duration of this drop occurs for a period of at least 10 seconds
There is a 4% desaturation from pre-event baseline
At least 90% of the event’s duration meets the amplitude criteria
The AASM Manual for the Scoring of Sleep and Associated Events, 2007
Obstructive Sleep Apnea
Respiratory Disturbance Index (RDI) – no longer used
 apneas, hypopneas, respiratory related arousals
Apnea-Hypopnea Index (AHI)
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total number of respiratory events / hours of sleep
Severity of OSA defined by the AHI:
less than 5
5 – less than 15
15 – less than 30
> 30
– not sleep apnea
– MILD
– MODERATE
– SEVERE
Portable Monitoring for OSA in Adults
In home diagnostic test for OSA
Advantages
 Convenience
 Less costly
 Attending technologist not required
Disadvantage
 Fewer physiologic variables that lead to misdiagnosis
 Technical limitations (apparatus malfunction) = repeat studies
 Validation of the device
Portable Monitoring for OSA in Adults
Types of Monitoring Devices
Type 1 – in sleep center, attended, overnight polysomnogram
Type 2 – record same variables as type 1, unattended
Type 3 – evaluate four physiologic parameters – not sleep
respiratory movement and airflow
heart rate
arterial oxygen saturations
(snoring), (position)
Type 4 – evaluate one or two parameters (saturation and airflow)
Portable Monitoring for OSA in Adults
Limitations of Type 3 devices
 Apnea Hypopnea Index – abnormal breathing events by recording
time as sleep can not be recorded
 Unless the patient was sleeping the entire recording time, the AHI
calculated by a portable monitor will likely be lower than an attended
polysomnogram
 Can not distinguish sleep stages
Portable Monitors and OSA
2005 Center for Medicare and Medicaid Services (CMS)
 evidence was not adequate to conclude, tests remained uncovered
2008
 Reconsidered and will allow for coverage of CPAP therapy based on
a positive diagnosis of OSA by home sleep testing
 Must fulfill all requirements in the National Coverage Determination,
CR6048
 Clinical evaluation as a positive diagnosis from PSG or unattended,
type 2, 3, 4(measuring at least 3 channels)
 Diagnostic tests that are not ordered by the beneficiary’s treating
physician and not considered reasonable and necessary
Portable Monitors and OSA
Clinical Guidelines for the Use of Unattended Portable
Monitors in the Diagnosis of Obstructive Sleep Apnea in
Adults
Portable Monitoring Task Force of the American Academy
of Sleep Medicine
1
Clinical Guidelines for the Evaluation, Management, and
Long-term Care of Obstructive Sleep Apnea in Adults
2
1. J Clinical Sleep Medicine, Vol 3, 2007
2. J Clinical Sleep Medicine, Vol 5, 2009
Portable Monitors and OSA
American Academy of Sleep Medicine Guidelines
 Should be performed only in conjunction with a comprehensive
sleep evaluation, preferably by a sleep medicine specialist
 May be used as an alternative to PSG for the diagnosis of OSA in
patients with a high pretest probability of moderate to severe OSA
 Should not be used in patients who have comorbid medical
conditions that predispose to sleep related breathing disorders
 Must record air flow, respiratory effort and blood oxygen information
Portable Monitors and OSA
Guidelines – cont
 Experienced persons should educate the patient or directly apply the
the monitoring equipment
 Should be a method to monitor the quality of the recordings
 Monitors must be capable of displaying the raw date for clinical
review
 All patients should have a follow-up visit with a provider able to
discuss the results of the test
Obstructive Sleep Apnea
Obstructive Sleep Apnea
Charles Dickens ( 1812 – 1870)
The Posthumous Papers of the Pickwick Club
 Described Joe, a fat boy, who was always excessively sleepy.
A loud snorer.
 First reported in 1965 during the study of severely obese patients 1
1. Brain Res 1965; 2: 167-186
Obstructive Sleep Apnea
Wisconsin Sleep Cohort Study
Random, n=602, ages 30 – 60
• Sleep disordered breathing as high as:
 24% of men
 9% of women
• 4% of men, 2% of women had symptomatic OSA
 AHI - >5
 Daytime hypersomnolence
NEJM 1993;328(17):1230-35.
Risk of OSA in the US Population
Results from the National Sleep Foundation Sleep In America 2005 Poll
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n= = 1506 adults (775 were women)
Mean age 49
Berlin Questionnaire
26% of respondents (31% of men and 21% women) found to be at
high risk of OSA
As many as one in four American adults could benefit from an
evaluation for OSA!
CHEST 2006; 130: 780-786
Identifying Patients with OSA
Clinical Presentation
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Threshold to symptoms highly variable
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Insidious
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Unaware or underestimate their degree of impairment
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Elderly patients aware of frequent awakenings
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Complaints of insomnia and unrefreshing sleep
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Excessive body movement, kicking in sleep
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Decrements in short-term memory
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Moodiness, irritability
Identifying Patients with OSA
Clinical Presentation – cont
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Lack of concentration
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Anxiety / depression
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Morning headaches – up to 50%
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Sensation of choking / dyspnea
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Decreased libido and impotence
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GERD, worse at night
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Nocturia, 28% of patients report 4 to 7 episodes of nightly
Obstructive Sleep Apnea
“My wife made me come!”
Obstructive Sleep Apnea
Cardiovascular disease
Hypertension
Coronary Artery Disease
Stroke
Arrhythmia
Pulmonary Hypertension
Congestive Heart Failure
Hematological
Platelet Activation
Hypercoaguable state
Neurological
TIA
Stroke
Daytime Fatigue
Memory / Intellectual impairment
Morning Headaches
Gastrointestinal
GERD
Fatty Liver
Metabolic
Altered Leptin Levels
Poor Gylcemic Control
Rapid Weight Gain
Psychological
Depression
Irritability / Mood Changes
Nocturnal Panic Attacks
Bed partner Relationships
Genitourinary
Impotence
Nocturia
Renal
Proteinuria
Focal Segmental Glomerulosclerosis
Immune
Elevated TNF-a
Elevated IL-6
Increased C3
Inflammation
C-reactive protein
Decreased IgM
Decreased NK cells
Berlin Questionnaire
Berlin Questionnaire
A means of identifying patients with sleep apnea
 n = 744 adults completed the questionnaire
 279 were in a high-risk group
 100 patients (equal representation of high and low risk group)
underwent a portable sleep study
 Being in the high-risk group predicted an RDI of greater than 5 with
a sensitivity of 0.86 and a specificity of 0.77
Ann Intern Med, 1999, 131: 485-491
Obstructive Sleep Apnea
Physical exam of the Upper Airway
Lack of consensus in describing the physical findings
Nose
 Nasal Obstruction
Oropharynx
 Mallampati Class
Retrognathia
 Risk of narrow airway at the base of the tongue
Mallampati Class
Scoring is as follows:
Class 1: Full visibility of tonsils, uvula and soft palate
Class 2: Visibility of hard and soft palate, upper portion of tonsils and uvula
Class 3: Soft and hard palate and base of the uvula are visible
Class 4: Only Hard Palate visible
Can Anaesth Soc J, 1985 Jul; 32(4) 250-1
Mallampati Class
Mallampati Score as an Independent Predictor of
Obstructive Sleep Apnea
n=137
80 (58%) had OSA as defined as AHI 5 or greater
Likelihood Ratio
Class I
Class II
Class III
Class IV
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4 of 12 patients
24 of 50 patients
45 of 65 patients
7 of 10 patients
0.4
0.7
1.6
1.7
For every increase in Mallampati Score by one,
 increased odds of having OSA by about 2 fold
 the AHI increased by more than 9 events / hour
Sleep 2006; 29 (7) 903-908
Obstructive Sleep Apnea - Hypertension
Sleep Heart Health Study
Multicenter Study, n= 6132
Age > 40 years, 53% female
AHI
<1.5
1.5 – 4
5 -14
15 – 29
Hypertension
43%
53%
59%
62%
>30
67%
JAMA 2000;283:1829-1836
JNC 7 – OSA identifiable cause of hypertension
JAMA 2003; 289: 2560-2572
Obstructive Sleep Apnea - Hypertension
Treatment of OSA with CPAP can Improve Hypertension
17 hypertensive patients, 7 normotensive patients
Moderate to severe OSA (AHI 60 +/- 19)
Four to six months CPAP
NEJM 2000: 343:967
Obstructive Sleep Apnea – Congestive Heart Failure
OSA in Dilated Cardiomyopathy: The effects of CPAP
N=8
Dilated cardiomyopathy and severe OSA (AHI 54)
Left ventricle ejection fraction
Baseline
37%
Stopped CPAP for one week
53%
CPAP
49%
45%
Lancet 1991; 338:1480-4
Obstructive Sleep Apnea – Cardiac Remodeling
Effects of Continuous Positive Airway Pressure on Cardiac
Remodeling as Assessed by Cardiac Biomarkers, Echocardiography,
and Cardiac MRI
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Prospective Study, n = 52, years 2007-2010
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AHI > 15, Epworth Sleepiness Score >10
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Evaluation before CPAP, 3 mos, 6 mos and 12 mos
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At each visit: TnT, CRP, and NT-proBNP levels, and a standard TTE
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CMR at baseline and 6 and12 months after the initiation of CPAP treatment.
CHEST 2012; 141(3):674–681
Obstructive Sleep Apnea - Cardiac Remodeling
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Following 12 months of CPAP therapy, levels of CRP, NT-proBNP, and TnT
did not change
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As early as 3 months after initiation of CPAP, TTE revealed an improvement
in right ventricular end-diastolic diameter, left atrial volume index, right atrial
volume index, and degree of pulmonary hypertension, which continued to
improve over 1 year of follow-up.
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Left ventricular mass, as determined by CMR, decreased from
2
2
159 g/m to 141 8 g/m as early as 6 months into CPAP therapy and
continued to improve until completion of the study at 1 year.
CHEST 2012; 141(3):674–681
Obstructive Sleep Apnea - Diabetes
CPAP Therapy of Obstructive Sleep Apnea in Type 2 Diabetics
Improves Glycemic Control During Sleep
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n=20, type 2 diabetes and newly diagnosed OSA
measured glucose levels every five minutes during sleep
baseline and after treatment with CPAP (average 41 nights)
 Mean glucose decreased in 10 of 11 subjects with glucose >
100mg/dL
 No decrease in subjects with glucose < 100mg/dL
J of Clin. Sleep Med. Dec 15, 2008
Obstructive Sleep Apnea - Diabetes
Impact of Untreated Obstructive Sleep Apnea on Glucose
Control in Type 2 Diabetes
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n = 60, 14 without OSA, 46 with OSA
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Controlled for: sex, race, BMI, waist circumference, Hgb A1C, year of
diagnosis, medications (insulin and oral), exercise, hypertension and
snoring.
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Increasing severity of OSA was associated with poorer glucose control.
Am J Respir Crit Care Med Vol 181. pp 507–513, 2010
Obstructive Sleep Apnea - Diabetes
Compared to controls the mean HbA1c:
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Mild OSA -
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Moderate OSA - increased by 1.93% (P= 0.0033)
Severe OSA –
increased by 3.69% (P< 0.0001)
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Linear Trend (P< 0.0001)
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inverse relationship between OSA severity and glucose control
in patients with type 2 diabetes
increased by 1.49% (P= 0.0028)
Am J Respir Crit Care Med Vol 181. pp 507–513, 2010
Obstructive Sleep Apnea – Mortality
One of the first reports of adverse consequences was published 1988
 8 year study, n=385
 severe OSA compared to less severe OSA (AHI >20, <20)
 significant increase in all cause mortality (death)
 change in mortality corrected by tracheostomy and CPAP
CHEST 1988; 94:9-14
Obstructive Sleep Apnea - Mortality
Sleep Apnea as an Independent Risk Factor for All-Cause Mortality:
The Busselton Health Study
Sleep Apnea diagnosed
Screened 380: 18 had moderate to severe OSA
77 had mild OSA
followed up to 14 years
6 of the 18 died 33% (moderate to severe OSA)
5 of the 77 died 6% (mild OSA)
SLEEP 2008 Vol 31, No 8
Obstructive Sleep Apnea – Mortality
Sleep Disordered Breathing and Mortality: Eighteen-Year
Follow-up of the Wisconsin Sleep Cohort
n= 1546, mean observation period of 13.8 years
AHI
0<5
5 - <15
15 - <30
>30
n
1157
220
82
63
Deaths
46 (4%)
16 (7.3%)
6 (7.0%)
12 (19.75%)
Cardiovascular death – 42% of persons with severe OSA
26% of persons without OSA
SLEEP 2008 Vol 31, No 8
Clinical Pearls
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Obstructive Sleep Apnea is a common medical condition that
contributes significantly to a multitude of comorbid diseases
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Presenting symptoms are heterogeneous and clinical evaluation
should be frequently considered
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Untreated OSA in intimately related to worsening of many medical
conditions
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Identification and treatment of OSA has a positive impact on individual
health and health care resources
The Nightmare – Henry Fuseli, 1781