Do you often feel on
waking that you haven’t had a good night’s sleep, despite going to bed early
enough? Do you feel tired and catch yourself yawning throughout the day,
although you seemingly slept for a reasonable time the night before? Or do you
find you wake several times in the night, sometimes with a ‘snort’? You may be
experiencing a condition known as obstructive sleep apnoea (OSA).
What is OSA?
OSA is a condition
characterised by interrupted breathing while sleeping. The word ‘apnoea’ means
absence of breathing and occurs when the muscles of the throat relax and the
tissues slump to such an extent that the airway closes up. An episode of halted
breathing is medically defined as apnoea if it lasts for at least ten seconds.
Another type of breathing impairment associated with OSA is hypopnoea, meaning
reduced breathing, which is when the airway is only partially obstructed by the
relaxation of muscles and slumping of tissues in the throat, and functions at
half capacity or less for at least ten seconds. (1)
What are the symptoms
of OSA?
If you sleep alone,
it is usually easier for OSA to go unnoticed, as the most obvious telltale
signs occur during deep sleep. However, you may find that you wake up several
times during the night, disrupting your sleep. Waking may be accompanied by a
snorting or gasping sound as the brain tells the body to come out of deep sleep
in response to the lack of oxygen in the blood, enabling a sudden, sharp intake
of breath. You may also notice that you wake up in a sweat. (1, 2)
Another symptom is
tiredness and sleepiness during the day. You may struggle to concentrate,
leading to more mistakes at work. You may yawn excessively, or find yourself
nodding off during quiet or dull parts of the day. If you wake several times at
night you will be able to trace the tiredness back to this, but the brain
sometimes tells the body to switch from deep to lighter sleep, rather than
fully waking, to restore normal breathing. Deep sleep is more restful for the
body, so fewer hours of deep sleep per night will increase tiredness during the
day. (1, 2)
The deep sleep
symptoms are often identified by another person, such as a partner, friend or
relative, when you sleep in their presence. They may tell you that you snore
loudly, or that it sounds like you’re struggling to take clear and complete
breaths. Crucially, they can identify your episodes of apnoea, telling you that
you stopped breathing for a prolonged period of time. (1)
Why does OSA happen?
Although most people
experience some relaxation and slumping of the throat’s tissues and muscles
during sleep, they can usually continue to breathe normally. Certain risk
factors increase a person’s chance of developing OSA. (1)
Being overweight or
obese is a major risk factor as excess weight carried on the neck can push the
airway narrower or shut completely, and make it harder for the muscles to
resist the slumping and keep the airway open. Men are at greater risk than
women, again mainly due to the fact that they are more inclined to carry excess
weight on the neck. This risk is more pronounced with a collar size of 17
inches or greater. (1)
Over the age of 40,
risk of OSA increases for both men and women, then again for women after they
reach the menopause. (1)
Natural variations in
the structure of the airway or nasal cavity can be responsible for OSA. Such
variations include a narrower airway than normal, enlarged tonsils or tongue, a
receding jaw, a deviated nasal septum, nasal polyps and enlarged adenoids in
children. OSA can also run in families. (1)
External factors such
as drinking alcohol before bed, smoking and taking sedatives including sleeping
tablets and anxiety medication can also make OSA more likely. (1)
Can OSA be treated?
If you think or
someone else thinks you may have OSA, visit your GP. They will rule out any
other causes of your symptoms and can refer you to a sleep centre for a firm
diagnosis. (1)
Once you are
diagnosed with OSA, your GP will advise you to make lifestyle changes if
needed, or maintain your current healthy lifestyle. Losing weight, stopping
smoking or reducing alcohol intake may be all that is needed to reverse OSA.
Other changes such as sleeping on your side instead of your back, keeping your
mouth closed and your nasal passages clear should also help. There are various
aids available to facilitate directing air through the nose instead of the
mouth, such as chin straps, mouth guards, mandibular advancement devices
(MADs), nasal strips and saline nasal sprays. If you find you often wake up
lying on your back, pillows can be purchased which are designed to prevent you
from rolling from your side onto your back while you sleep. (1, 2)
If your OSA is not
relieved by these changes, it may be worth considering a week’s trial of a
continuous positive airway pressure (CPAP) device. This device pumps air
through a mask into your airway to stop it from closing throughout the night.
The trial is expensive at £100, but if it is successful you may be put on an
NHS waiting list for a free CPAP of your own. CPAPs are also available to buy.
Click here for more information. (1, 2)
If a variation in
structure of the airway is the cause, surgery can be performed to correct this.
(1)
Can OSA cause any
other problems?
If not treated, OSA
will continue to cause constant tiredness, poor concentration and irritability,
negatively affecting your quality of life. Furthermore, it may lead to other
health problems including high blood pressure, heart attacks and strokes,
changes in heart rhythm, and even type 2 diabetes. (1)
If you receive a
diagnosis of OSA and you drive, you’re legally obliged to inform the DVLA, as is the case with all conditions which may
impair your driving. It’s possible that you’ll be asked not to drive until your
symptoms are under control. (1)
Visit the Sleep Apnoea Trust website for further support.
References
- NHS Choices. Obstructive sleep apnoea [cited 28 March 2018]. Available at: https://www.nhs.uk/conditions/obstructive-sleep-apnoea/
- The Guardian. Seven ways to… prevent snoring [cited 28 March 2018]. Available at: https://www.theguardian.com/lifeandstyle/2018/mar/26/seven-ways-to-prevent-snoring
Author: Gabby Gallagher MPharm
Medically reviewed by: Superintendent pharmacist Margaret Hudson BSc(Hons)MRPharmS 09/04/18