Understanding and Recognizing Obstructive Sleep Apnea

Barbara Phillips, MD, MSPH, FCCP

August 9, 2008

Disclosures

• Consulting, speaking– Boehringer Ingelheim– Department of Transportation, FMCSA– GSK– Jefferson County Metro Government– TempurPedic– Ventus

• Leadership position– American College of Chest Physicians– National Sleep Foundation

Pre-Test Questions

Meet Mr S Nora

• A 55 year old man complains that his wife will no longer sleep with him because he is too noisy and it is disrupting her sleep.

• This has been going on for several years, but has worsened in the past 18 months as he has gained weight.

• Last year, he ran off the road while driving back from a sales meeting in the evening.

Mr S Nora

• Past Medical History– Hypertension– Glucose intolerance

• Medications– Metoprolol– HCTZ

• Examination: bp 146/94, BMI 33 Kg/m2

• Neck circumference=18.5 inches

The Epworth Sleepiness Scale  

How likely are you to doze off or fall asleep in the following situations, in contrast to just feeling 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 chose the most appropriate number for each situation:

0=would never doze1=slight chance of dozing2= moderate chance of dozing3=high chance of dozing

 Situation Chance of Dozing Sitting and reading _____Watching TV _____Sitting, inactive, in a public place _____As a passenger in a car for an hour _____Lying down in the afternoon _____Sitting and talking to someone _____Sitting quietly after a lunch without alcohol _____In a car, while stopped for a few minutes in traffic _____

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Risk Factors for Obstructive Sleep Apnea

• Obesity (Kripke DF 1997; Tsai WH 2003)

• Male Gender (until about age 50)• Postmenopausal state (Young T, 2003)

• Upper airway anatomic obstruction• African-American, Asian, or Hispanic

ethnicity (Kripke DF 1997; Young T 2003; Stepanski E 1999; Li KK 1999)

• Being a football player (George CF 2003) or truck driver (Howard, 2005)

Clinical Practice Recommendation

• Practice Recommendation: The risk for obstructive sleep apnea correlates on a continuum with obesity, large neck circumference, and hypertension. Combinations of these factors increase the risk for OSAHS in a non-linear manner.

• Evidence-Based Source: Institute for Clinical Systems Improvement

• Web Site of Supporting Evidence: http://www.icsi.org/sleep_apnea/sleep_apnea__diagnosis_and_treatment_of_obstructive_.html

• Strength of Evidence: • Class A: Randomized, controlled trial; Class B: Cohort study; Class C: Non-

randomized trial with concurrent or historical controls, Case-control study, Study of sensitivity and specificity of a diagnostic test, Population-based descriptive study; Class D: Cross-sectional study, Case series, Case report; Class R: Consensus statement, Consensus report, Narrative review

Clinical Practice Recommendation

• Practice Recommendation:Polysomnography is the accepted standard test for the diagnosis of obstructive sleep apnea syndrome. The benefit of using attended polysomnography for diagnosis is the ability to establish a diagnosis and ascertain an effective CPAP treatment pressure.

• Evidence-Based Source:Institute for Clinical Systems Improvement

• Web Site of Supporting Evidence: http://www.icsi.org/sleep_apnea/sleep_apnea__diagnosis_and_treatment_of_obstructive_.html

• Strength of Evidence: • Class C: Non-randomized trial with concurrent or historical controls, Case-control

study, Study of sensitivity and specificity of a diagnostic test, Population-based descriptive study; Class D: Cross-sectional study, Case series, Case report; Class M: Meta-analysis, Systematic review, Decision analysis, Cost-effectiveness analysis; Class R: Consensus statement, Consensus report, Narrative review

Weight Loss for OSA

• Modest (10%) weight loss results in significant improvement in AHI

(Yee BJ, Int J Obes 2006)

• Bariatric Surgery results in 75-88% cure rate at 1 year, independent of approach. (Guardiano SA Chest 2003, Crooks, PF, Annu Rev Med 2006)

Change in Weight and BMI over 4 Yrs(Peppard PE, JAMA 2000, WSCS, n=690)

-20% to< -10%(n = 22)

-10% to< - 5%

(n = 39)

- 5% to< + 5%

(n = 371)

+ 5% to< + 10%(n = 179)

+ 10% to+ 20%

(n = 79)

Mea

n C

han

ge

in A

HI,

Eve

nts

/h

Change in Body Weight

From JNC7…

Refractory HTN in OSA(Logan J Hypertension 2001)

• N = 41

• BP > 140/90 on 3 antiHTN meds

• Excluded causes of secondary HTN, poor compliance

• Prevalence of 95% in men and 65% of women

Effect of CPAP on Blood Pressure in Hypertensive Patients

(Becker HF, Circ, 2003)

Polysomnography Results

• AHI 42 events/hour

• Sa02 lowest 76%; 26 minutes with Sa02 below 85%

• Sleep Efficiency 64%, TST 4.8 hours

• No Stage 3 sleep, 5% REM sleep

CMS’s Definition of Obstructive Sleep Apnea (OSA)

CPAP will be covered for adults with sleep-disordered breathing if:– AHI or RDI > 15 OR– AHI or RDI > 5 with (“mild, symptomatic”)

• Hypertension• Stroke• Sleepiness• Ischemic heart disease• Insomnia• Mood disorders

Apnea + Hypopnea Index (AHI), AKARespiratory Disturbance Index (RDI)

And Oxygen Desaturation Index (ODI)

• AHI = Apneas + Hypopneas

Total Sleep Time, in Hours• RDI = AHI, more or less

(may include RERA’s)

• ODI = Number of 4% desats/hr• SDB = Sleep-Disordered Breathing

(What you say when you are not sure what you are including. May include snoring, RERA’s, oxygen desaturation)

Sleep Heart Health Study: Apneas and Hypopneas

Decrease in airflow or chest wall movement to an amplitude smaller than approximately 25% (apnea) or 70% (hypopnea) of baseline

At least 10 seconds Associated with oxyhemoglobin

desaturation of 4% or greater as compared with baseline

L EOG

R EOG

O1 A2

C3 A2

Chin EMG

ECG

Leg EMG

NC AF

Th AF

Chest

Abd

SaO2

Apnea

Arousal from sleep

L EOG

R EOG

O1 A2

C3 A2

Chin EMG

ECG

Leg EMG

NC AF

Th AF

Chest

Abd

SaO2

Severity Criteria Based on PSG From the American Academy of Sleep

Medicine (Sleep, 1999)

• “Mild” sleep apnea is 5-15 events/hr

• “Moderate” sleep apnea is 15-30 events/hr

• “Severe” sleep apnea is over 30 events/hr

• (“Events” includes apneas, hypopneas, and RERA’s)

Which Patient Has “Mild” OSA?

Patient 1 Patient 2

AHI (events/hr) 40 10Apnea duration (secs) 10-22 10-90

Lowest Sa02 (%) 90 71

% REM on study 18 0

Arousals/hr 8 80

Cardiac arrhythmias none v tach

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Increased Risk of Crash with OSA (FMCSA, 2007)

Howard ME, AJRCCM 2004N=3268

George, C F P Thorax 2001;56:508-512

Crashes and CPAP (n=210, with OSA, 210 controls)

BMI and OSA Predict Atrial Fibrillation(Gami AS, JACC 2007)

Association of nocturnal arrhythmias with sleep-disordered breathing. The Sleep Heart Health

Study (Mehra et al, AJRCCM 2006)

(N= 228 with RDI > 30 c/w n=338 with RDI < 5)

OR Adjusted for Age, Sex, BMI, CHD

NSVT 3.4 (1.03-11.2)

CVE 1.74 (1.11-2.74)

Atrial Fibrillation 4.02 (1.03-15.74)

Recurrence of Atrial Fibrillation Following Cardioversion Is Higher in Patients with

Untreated Obstructive Sleep Apnea(Kanagala et al, Circ, 2003)

0102030405060708090

100

Controls (n=79) Treated OSA(n=12)

Untreated Osa(n=27)

% Recurrence at 12 Months

*p<0.009 compared to controls**p<0.013 compared to treated OSA

*,**

Stroke or Death (Yaggi HK NEJM 2005)

Hazard Ratios for Death by RDI Adjusted for BMI

(Lavie P, Eur Respir J 2005)

Relative Mortality RDI > 50/hr (Lavie Eur Respir J 2005)

CPAP, OSA, and Death(Doherty LS, Chest 2005)

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Clinical Practice Recommendation

• Practice Recommendation: Lifestyle modifications, particularly weight loss and reduced alcohol consumption can play a significant role in the reduction of severity of sleep apnea

• Evidence-Based Source:Institute for Clinical Systems Improvement

• Web Site of Supporting Evidence:http://www.icsi.org/sleep_apnea/sleep_apnea__diagnosis_and_treatment_of_obstructive_.html

• Strength of Evidence:• Class A: Randomized, controlled trial; Class B: Cohort study; Class C:

Non-randomized trial with concurrent or historical controls, Case-control study, Study of sensitivity and specificity of a diagnostic test, Population-based descriptive study; Class D: Cross-sectional study, Case series, Case report; Class R: Consensus statement, Consensus report, Narrative review

Alcohol and OSA• “Most but not all studies … have

demonstrated harmful effects on nocturnal respiration, including increased number and duration of hypopnea and apnea events.” (Young T, AJRCCM 2002)

• Alcohol may not change CPAP pressure needed (Wessendorf TW, Sleep Med Rev 2002)

Cigarette Smoking and OSA• Most data indicates relationship

– OR 2.05 (Khoo SM, Respir Med 2004, n=2298)– OR 2.5 (Kashyap R, Sleep Breath 2001, n=108)– OR 4.4 (Wetter D, Arch Intern Med 1994, n=811)

• Some does not– No diff (Casasola, Sleep Breath 2002, n=38)

• Ex-smokers do NOT appear to have increased risk of OSA

• Parental smoking appears to be a risk for SDB in children (Kadatis AG, Pediatr Pulmonol 2004, n=3680)

Cigarette Smoking and Other Problems

• Reduced CPAP compliance

(Russo-Magno P, J Am Geriatr Soc 2001, n=33)

• Greater oxygen desaturation

(Casasola, Sleep Breath 2002, n=38)

Exercise for OSA?(Quan SF, Sleep Breath 2007)

• 4275 SHHS participants

• Logistic regression analysis

• > 3 hrs/week of self-reported vigorous exercise

reduced risk of AHI > 15 (Adjusted OR, 0.68;

95%CI, 0.51-0.91 )

• Similar but weaker associations for less vigorous

exercise or different definitions of OSA

Oral Appliance Reviews• Cochrane Database Review (Lim, 2004)

– OA improved sleepiness and SDB compared to controls, but CPAP is the more effective of the two treatment modalities

• Ferguson KA, Sleep 2006– 52% chance of control of sleep apnea with OA– Successful treatment more likely in mild-to-moderate sleep apnea – Greater degrees of mandibular protrusion more successful. – High BMI predicts failure

• Hoekema, Crit Rev Oral Biol Med, 2004– OA are more effective than controls for treating OSA, and possibly

more effective than UPPP– OA are less effective than CPAP, but patients generally preferred OA

therapy to CPAP– OA are a viable treatment for mild-moderate OSA

Do Oral Appliances Work?(Cochrane Database Syst Rev. 2006 Jan 25;(1):CD001106)

“CPAP is effective in reducing symptoms of sleepiness and improving quality of life measures in people with moderate and severe obstructive sleep apnea (OSA). It is more effective than oral appliances in reducing respiratory disturbances in these people but subjective outcomes are more equivocal. Certain people tend to prefer oral appliances to CPAP where both are effective. This could be because they offer a more convenient way of controlling OSA.”

Indications for Oral Appliances (Kushida C, Sleep 2006)

– Primary snoring

– Mild to moderate OSA patients who: • Prefer OAs to CPAP• Do not respond to CPAP• Are not appropriate candidates for CPAP• Fail treatment attempts with CPAP or behavioral changes

– Patients with severe OSA should have an initial trial of nasal CPAP [before considering OAs]

– Upper airway surgery may also supersede use of OAs in patients for whom these operations are predicted to be highly effective in treating sleep apnea

Types of Oral Appliances (OA)

• There > 50 different OAs commercially available; only about 30 have been approved by the FDA for OSA

• Two basic types:– Mandibular repositioners (MRD); reposition and

maintain the mandible and tongue in a forward position

– Tongue retainers (TRD); engage and hold only the tongue in a forward position without affecting the mandible or teeth (not FDA approved for OSA)

Consequences of Sleep Apnea

• Sleepiness• Impaired quality of life• Decreased cognitive function• Increased hospitalizations and health care

costs• Increased car accidents• Impaired glucose control• Hypertension• Increased cardiac risk• Increased mortality rate• Impotence

Effectiveness of Nasal CPAP

• Decreases sleepiness• Improves quality of life• Improves cognitive function• Decreases hospitalizations and health care

costs• Decreases car accidents• Improves glucose control• Lowers blood pressure• Reduces cardiac risk• Reduces mortality rate• Reverses impotence

Meet Ms S Nora

• Mr Nora’s 52 year-old wife presents with a complaint of sleep onset insomnia.

• This started at about the time of menopause, but has gotten worse; she blames her husband’s snoring

• She notes that she has gained weight recently, and wonders if her poor sleep is related

Ms S Nora

• Past Medical History– Hypothyroidism– Depression

• Medications– Thyroxin– Buproprion

• Examination: bp 128/74, BMI 28 Kg/m2

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The effects of gender and BMI change with aging

AFTER THE AGE OF 50, GENDER BECOMES AN UNIMPORTANT VARIABLE

AFTER THE AGE OF 60, BMI BECOMES AN UNIMPORTANT VARIABLE

Tischler PV. JAMA. 2003

Menopause and Sleep Apnea(Young T, AJRRC, 2003, n=589)

Changes in Airway Age - MRI findings

• Soft palate gets longer• Pharyngeal fat pads

increase in size• Shape of bony

structures around pharyngeal airway change

• Response of genioglossus muscle to negative pressure stimulation diminishes

Malhotra et al. Am J. Med, 2006. 119:72.e9-e14

Midsagittal magnetic resonance image illustrating anatomic structures of interest

Women with Sleep Apnea Are Different from Men

Women with OSA are more likely to– present with insomnia– be depressed– have thyroid disease– report nightmares, palpitation, and hallucinations– have comorbid Restless Legs Syndrome

They are less likely to have snoring and witnessed apneas

Valipour A. Sleep 2007

Shepertycky and Kryger, Sleep 2005

Women Are Under-diagnosed

• Symptoms of insomnia, chronic fatigue or depression may not be recognized as attributable to OSA– delay in diagnosis and treatment

• Severe cases of OSA are more likely to be referred; UARS may not be diagnosed or treated

• Women are less likely to be accompanied to clinic by a bed partner, whose complementary sleep history is often important in identifying sleep symptoms

The Stereotype….

The Reality.

Ms S Nora: Polysomnography Results

• AHI 18 events/hour

• Sa02 lowest 86%

• Sleep Efficiency 54%, TST 4.1 hours

• No Stage 3 sleep, 15% REM sleep

Treatment of Sleep Apnea

• Behavioral Therapy– Avoid alcohol, nicotine and

sleep medications– Lose weight if overweight

• Physical or Mechanical Treatment– CPAP (Continuous Positive

Airway Pressure)– Oral appliance

• Surgery in very rare cases

Understanding and Recognizing Obstructive Sleep Apnea

• Sleep apnea is common, treatable, and associated with morbidity and mortality.

• The best-proven consequences of sleep apnea are hypertension and car crashes. Which kill.

• History and physical findings differ between men and women; PSG is the definitive test.

• CPAP treatment is safe, effective and inexpensive. Lifestyle changes can help.

• Oral appliances are safe, somewhat effective, and inexpensive.

Post-Test Questions

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