Sleep apnea: the essentials Simon Bowler Director Medicine Mater Adult Hospital Mater Private Hospital
Queensland Sleep
Sleep Apnea Most OSA is straightforward Most does not need specialist attention Areas of uncertainty CPAP vs no CPAP therapy in borderline cases Disconnect between symptoms and measurements More complex forms (eg central)
Commercial drivers need specialist review
Who should have a sleep study?
How do you assess severity of OSA? Who needs CPAP – who doesn’t?
What is the risk of untreated OSA? What to do if patient doesn’t tolerate CPAP? Can changing posture cure sleep apnea Does weight loss fix sleep apnea Sleep apnea, driving and the law?
How common is sleep apnoea? 30-60 yr old public servants
602 polysomnograms AHI>15 (ie sig. OSAS) in
• 17% male heavy snorers 7.5% all males • 7% female heavy snorers 2% of all females.. Wisconsin Sleep Cohort Study NEJM 1996;328:1230
Scenario Peter aged 48 Bulldozer driver coal fields Well. BMI 35 Hypertension on Coversyl Snores - some apneas No daytime somnolence ESS 6 No MV accidents 5
1. General meas: Wt reduction 2. attention to nasal patency 3.± avoid supine sleep (If less sleepy; intolerant CPAP) MAS
± MAS
CPAP
± CPAP (If sleepy++; marked supine or REM effects or hypoxia)
….
Scenario Pete: “I’m feeling fine - no way I’m wearing a Darth Vader mask to bed”
Wife Susan says: “You’ll have a heart attack and die if you don’t or end up paraplegic in a car accident” 13
The consequences of OSA Susan: from the web:
NIH: “When your sleep is interrupted throughout the night, you can be drowsy during the day. People with sleep apnea are at higher risk for car crashes, workrelated accidents and other medical problems. If you have it, it is important to get treatment.”
ASA: “..increased chance of heart attack or stroke ..x4 as likely to have a motor vehicle accident
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CARDIOVASCULAR DISEASE
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Sleep apnea and CV disease Metabolic syndrome
Sleep apnea
?
Cardiovascular events
16
Fatal events
OSA CPAP and CV outcomes Non Fatal events
Months
Marin Lancet 2005; 365: 1046
Months
17
Outcomes: MI / CVA vs normals • Severe untreated OSA had x3 the chance of a heart attack or stroke compared with normal or treated severe OSA
Caveats •not a randomised study • differences between CPAP / no CPAP groups not excluded • no account of subsequent Rx or compliance
Marin Lancet 2005; 365: 1046 18
Meta analysis of CPAP and Syst BP
CPAP produces small but significant drop in BP Fava C Chest 2013 Online 10.1378/chest.13-1414
Hundreds of episodes a night of semi asphyxiation, hypoxia, sympathetic overdrive, recurrent arousal and fragmented sleep experienced over years can be very bad for some / most but perhaps not all patients
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Sleep and driving
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CPAP and driving skills: reaction time OSA pre CPAP NL x 2 OSA post CPAP
Mazza ERJ 2006 28: 1020
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CPAP + number of MVA’s n= 210 age 52± 11y BMI 35±10 RDI 54±29
OSA George Thorax 2001;56:508
No OSA
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For Pete ? • An asymptomatic patient • What to do • Will CPAP make him feel better?
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Treatment based on AHI Pete’s RDI
AHI Mild 0
10
Moderate 15
Severe
20
30
1. General meas: Wt reduction 2. attention to nasal patency 3.± avoid supine sleep (If less sleepy; intolerant CPAP) MAS
± MAS
CPAP
± CPAP (If sleepy++; marked supine or REM effects or hypoxia)
….
CPAP will in disease modeling: Increase the probability of survival by 25%.
Decrease the relative risk of having a cardiovascular event by 46%
Decrease the relative risk of having a stroke by 49% Decrease the relative risk of having an RTA by 31%. Increase the probability of event-free survival by 92%. for a cost-reduction of £973 (95% CI: -£1,983; £1,508) over 14 years
Guest J Thorax online April O8 10.1136/thx.2007.086454
Effect of CPAP in non sleepy OSA • Parallel gp study • CPAP vs Sham Baseline mean • n=29 vs 25 • ESS 8 vs 6 • BMI 29 vs 29 • AHI 57 vs 57 • 6 weeks Rx No benefit found.. Barbe Ann Intern Med. 2001;134:1015
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Positional therapy and OSA 16 pats with positional OSA Time supine fell 42.8 ±26 to 5.8 ±7.2 % AHI fell 26.7 ± 17 to 6.0 ±3.0 ESS 9.4 ±5 to 6.6 ±5 Used device for 74% nights 8.0± 2.0h/n Good compliance at 3 months – results persisted Heinzer Sleep 2012:13;425
Weight reduction and OSA 25 pat (17m) 44y; 154kg; BMI 52.7 Lap band Mean weight loss 44.7kg (50% excess weight loss) AHI fell from 61.6 ±34 to 13.4 ± 13 ESS from 13 ±7 to 3.8 ±3 Improved depression, T2DM, metabolic syndrome
Int J Obesity 2005;29:1048
For Pete ? • Long term implications for untreated sleep apnea in an asymptomatic patient are unknown • Is he really asymptomatic ? •? Trial of CPAP •? MWT (NB occupation) • Treat cardio vascular risk factors • Lose weight • If he’s really asymptomatic observe • Control of snoring
only
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http://www.austroads.com.au/
In summary: driving and sleep If the patient has sleep apnea (RDI>10) and (or) is sleepy (ESS ≥ 16) and or has had sleepiness driving or crashes due to sleepiness –
Must use CPAP (and have improved sleepiness) You must be happy the patient is adhering (ESS; download) You should fill in an F7312 and the patient should submit You have legal protection in reporting the patient if you believe non compliance or a risk driving
Refer if worries
If the patient holds a commercial license and meets above condition Should be referred to a sleep physician