Transcript OSA
Is Snoring Bad For You?
Dr. Shanthi Paramothayan
BSc MBBS PhD LLM MScMedEd FHEA FCCP FRCP
Consultant Respiratory Physician
Honorary Senior Lecturer
St. Helier University Hospital
8th September 2012
History
Mr. AN
35 years
Cab driver
Non smoker
Minimal alcohol
Divorced
Depressed
Snores loudly
Daytime somnolence
Poor sleep
Fatigue
Un-refreshed
History
New girlfriend reports:
Loud
snoring
Apnoeas
Snorts and grunts
Examination
Obese : Wt = 182 kg, Ht = 190 cm, BMI =
50
Collar size = 23 inches
BP = 150/95
Narrow oropharynx
Chest clear
Epworth Sleepiness Score: 16
Epworth Sleepiness Score
How likely are you to doze off or fall asleep during the following
situations, in contrast to just feeling tired?
Score of 0 to 3 where 0= would never dose; 1= slight chance;
2= moderate chance; 3 = high chance.
Situation
1.
2.
3.
4.
5.
6.
7.
8.
Sitting and Reading
Watching TV
Sitting inactive in a public place
As a passenger in a car for an hour
Without a break
Lying down to rest in the afternoon
Sitting and talking to someone
Sitting quietly after lunch (no alcohol)
In a car while stopped in traffic
Score
Epworth Sleepiness Score
Score of <
Score of >
breathing
Score of >
Score of >
Score of >
6: Normal
8: Possible sleep disordered
12: Probability of OSA
16: High probability of OSA
20: Consider narcolepsy
Maximum score = 24
So what is the diagnosis?
Differential diagnosis of snoring:
1.
Simple snoring – consider ENT causes (e.g
deviated septum). May be positional and
exacerbated by alcohol, sedatives
2.
Upper airways resistance syndrome
(UARS)
3.
Obstructive sleep apnoea (OSA)
Hypersomnolence
1.
2.
3.
4.
5.
6.
7.
8.
UARS
OSA
Narcolepsy
Obesity-hypoventilation (Pickwickian)
syndrome
Insomnia/other sleep related disorders
Restless Leg Syndrome (periodic limb
movement)
REM behaviour disorder
Chronic insufficient sleep
Obstructive Sleep Apnoea
Apnoea means “without breath” in Greek
People with OSA stop breathing repeatedly during their sleep,
often for a minute or longer, even up to 100 x every night
Apnoea: complete obstruction of airways for > 10 secs
Hypopnoea: Partial obstruction of airways (30 –50 %) for > 10
secs
AHI: apnoea/hypopnoea index (no / hour, same as RDI)
Mild OSA: AHI of > 10 / hr
Moderate OSA: AHI of > 20 / hr
Severe OSA: AHI of > 30 / hr
Obstructive sleep apnoea and upper airways
resistance syndrome
UARS:
Snoring with brief, repetitive arousals due to increases in
resistance to airflow and increased respiratory effort
Negative intrathoracic pressure autonomic and CV
changes hypertension. No oxygen desaturations
Sleep fragmentation results in daytime somnolence
OSA:
Snoring with apnoeas and hypopnoeas and oxygen
desaturations ( 4% from baseline)
The AHI is a continuous variable like BP, so separating normal
from abnormal is difficult.
Epidemiology of OSA
Common: 5 % of women and 10 % of men aged
over 35 (USA: Wisconsin cohort study, 9-24% in
M and 4 – 9% in F)
M:F = 2-3 : 1 ( in F after menopause)
Prevalence increases with age
Race: Prevalence > in African-Americans
Mortality and Morbidity: retrospective data
suggest the greater mortality in patients with AHI
> 20 / hour
Risk Factors for OSA
Obesity: BMI > 25, collar size > 17 inches
Age: loss of muscle mass in airways and neck and
excess fat
Nasal problems that impede airflow
Enlarged tonsils and adenoids (children)
Hypothyroidism
Acromegaly
Other structural abnormalities: retrognathia,
micrognathia
Amyloidosis, neuromuscular disorders, Marfan’s,
Down’s
Can be exacerbated by: supine position, alcohol
and sedatives
Low threshold for referral in
Overweight
patients
Snoring or disturbed sleep
Unexplained tiredness
Unexplained sleepiness
Lack of concentration, memory, libido
Resistant hypertension (requiring many
antihypertensives
Metabolic syndrome: Diabetes, HT,
hypercholesterolaemia
Cardiovascular disease (heart failure,
arrhythmias,
So what happens in OSA?
Site of obstruction is soft palate, extending to the
region at the base of the tongue (no rigid structures
to hold airway open)
When awake, muscles in the region keep passages
open
When asleep, muscles relax, and there is reduced
neuromuscular activity, causing airway collapse and
obstruction of airway
This results in an oxygen desaturation
When breathing stops, the sleeper awakens (arousal)
for a few seconds and there is a rise in BP
Repeated arousals cause sleep fragmentation (no
REM sleep) and un-refreshed sleep
Normal
Sleep apnoea-hypopnoea syndrome
Upper airway resistance increases during sleep
in normal subjects
Typical presentation of OSA
Symptoms are insidious and often present for
years
Snoring, loud and habitual and bothersome to
others
Witnessed apnoeas that end with a loud snort
Gasping and choking sensations
Restless sleep, frequent arousals, nocturia
Feeling un-refreshed, morning headaches
Excessive sleepiness during day
Poor: concentration, memory, libido
Problems with family and work
Road traffic accidents (RTA)
Approach to a patient with possible OSA
Get clear history and talk to witnesses (partner)
Driving history and occupation (truck drivers, train
drivers)
Assess daytime sleepiness (ESS) and other
symptoms
Weight, height and calculate BMI
Collar size
Oropharynx (tonsils)
Nasal airflow
Blood pressure
Cardiovascular and respiratory examination
Investigating patients with possible OSA
Bloods: FBC, U+E’s , glucose, thyroid
function
Epworth sleepiness score
(Multiple sleep latency test)
If necessary: ECG, CXR
ENT referral
Investigating patients with possible OSA
Overnight pulse oximetry
Overnight limited sleep study: oximetry,
thoracic and abdominal wall movement,
oronasal airflow, snore volume, BP
Full polysomnography: as above plus
Leg movements (anterior tibialis EMG) and
video,
Sleep stages (EEG, EMG, EOG)
ECG and blood pressure
Consequences of OSA
Untreated OSA is related to a significant mortality risk, 3X (Sleep,
American Heart Association, American College of cardiology,
OSA is a risk factor for developing nocturnal hypertension
(independent of other factors (Davies, Thorax 1998)
Recent evidence that OSA causes hypertension and treatment with
CPAP improves BP (Becker et al, Circulation 2003, 107:68-73,
Nieto et al, JAMA 2000, 283:1829-1836, Peppard P, N Engl J Med
2000, 342: 1378-1384)
OSA increases risk of stroke, heart block and MI
Risk of OSA is increased in patients with pulmonary hypertension
Link between OSA and heart failure (also with central sleep
apnoea)
Increased risk of RTA
Evidence of link between OSA and CV disease
Animal models
Epidemiology
Association long suspected ? Confounding
factors?
Wisconsin Sleep Cohort study
– 18 year follow up of 1522 (30-60 yrs) with mild,
moderate, or severe OSA or no OSA
– Mortality was 19% with severe OSA v 4% with no OSA
Sleep study (Australia)
– 14 year study of 380
– Moderate-to-severe sleep OSA was an independent risk
factor for dying (33% in severe OSA v 7.7% in no OSA)
Mechanism of increased cardiovascular morbidity in
OSA
OSA associated with increased CV morbidity
Intermittent hypoxia increases formation of reactive
oxygen species and oxidative stress
Reactive oxygen species cause rupture of unstable
atherosclerotic plaques
Inflammatory pathways activated
Inflammatory cytokines and adhesion molecules:
cell/leukocyte/platelet interaction
Endothelial dysfunction
Syndrome Z
Hypertension
Central Obesity
Insulin resistance
Hyperlipidaemia
OSA
Syndrome X
Syndrome Z
So suspect OSA in patients with above risk
factors
Management of patients with OSA
Depends on severity of OSA and symptoms
General:
Weight reduction (dietician, medication)
Advice on sleep position (tennis ball !)
Avoidance of alcohol and sedatives
Treat nasal congestion
Try devices to stop snoring (e.g snorban)
Information, telephone numbers and websites
Information about Driving : Patient must inform
DVLA if they are being investigated for OSA
Management of patients with OSA
Oral appliances
CPAP
Medication: Modafinil (Provigil)=stimulant. For
patients still symptomatic despite CPAP
Surgery: uvulopalatopharyngoplasty (UPPP),
craniofacial reconstruction, tracheostomy
Oral Appliances
Oral appliances move tongue or mandible
forward
Suitable as 1st line therapy for mild OSA if
patient doesn’t tolerate CPAP
Not as effective as CPAP (Engleman, 2002)
Mandibular advance devices move lower jaw
forward
Tongue-retaining devices pull tongue forward
Should be fitted by specialist
dentist/maxillofacial surgeon
Side effects: TMJ pain, excessive salivation
CPAP (Continuous Positive Airways Pressure)
Treatment of choice in moderate and severe OSA
CPAP improves snoring, sleep quality, daytime
sleepiness, mood, cognitive function, QOL (Becker,
2003)
CPAP decreases BP and has other cardiovascular
benefits in patients with OSA (RCT evidence)
Compliance is a major problem: 50 – 70 % use it
regularly and significantly
Common side effects: rhinorrhoea, dry mouth, dry
eyes, nose bleeds, claustrophobia, aerophagia
Need regular assessment, advice, help with mask
fitting, humidifier etc – so need competent technical
staff
Patients with OSA can drive once established
effectively on CPAP
So what happened to my cab driver?
Overnight limited sleep study showed
significant OSA
Patient given information about weight
reduction, referred to dietician
Patient referred urgently for CPAP
Patient advised NOT to drive and to inform
DVLA until established on CPAP
Now what about you?
Do
you snore?
What
If
is you ESS?
you snore and your ESS is >
12…………
Central Sleep Apnoea
Absent/reduced ventilatory drive
Congenital
Ondine’s curse
Acquired
Destructive brain lesions
Neuromuscular disease
Severe obesity
Chest wall abnormalities
Conclusions
OSA is common. Need increased awareness (especially GP’s) and
referral for sleep study
Pulse oximetry suitable for majority with OSA but will miss UARS
and mild OSA, or patients with hypoxia for other reasons
Limited sleep study can be done at home and will be sufficient for
the majority with OSA but may miss other problems
Increasing evidence that OSA is a significant risk factor for
systemic hypertension, cardiovascular disease, pulmonary
hypertension and all cause mortality
Evidence that treatment of OSA reduces risk
OSA responsible for a significant number of road traffic accidents
CPAP is the treatment of choice for OSA