Science, Sleep Apnea, Solutions
Sleep Apnea: Screening, Testing and Treatment
Sleep apnea is a serious condition where your airway repeatedly closes during sleep, depriving you of oxygen until you gasp awake.
The combined effects of disturbed sleep and repeated bouts of low oxygen cause lots of problems for your physical and mental health. Despite this, many sufferers remain undiagnosed.
But how do you get diagnosed?
There are several steps towards understanding and addressing sleep apnea:
- Signs – know how to spot potential sleep apnea.
- Questionnaires – answer some questionnaires to assess your risk.
- Diagnosis – undergo a sleep study.
- Treatment – start treatment appropriate for the severity of your condition.
Signs of sleep apnea
Loud snoring alone does not necessarily mean you have sleep apnea. If you can’t tell where loud snoring ends and sleep apnea begins, ask yourself or your partner if you have any of the following:
- Very loud snoring, with periodic silence followed by choking/gasping
- Headaches and a sore throat in the morning
- Excessive sleepiness in the daytime
- Lack of concentration
- Mood swings and changes in behaviour
Side note: Can SnoreLab identify sleep apnea?
This is a question we get asked a lot. Some users have discovered sounds in their recordings that indicate apnea events, and then found them useful in subsequent medical consultations. But, it is important to note that SnoreLab is not a tool for sleep apnea screening. It is our goal to create a system to identify risky periods in your session using the tell-tale sign of silence followed by gasping or choking. That said, once we have created this, it will not be diagnostic. This is because sleep apnea is characterised by more than sound profile alone and requires a sleep study to be properly assessed.
Screening questionnaires
If you are showing the signs of sleep apnea, before getting more in-depth diagnostic tests, it is useful to assess your risk using some screening questionnaires.
Epworth Sleepiness Scale
Feeling excessively sleepy during the day is a key symptom of sleep apnea. Therefore, it is a good idea to measure your fatigue by using the Epworth Sleepiness Scale [1]. This questionnaire gives you a numerical score based on your self-assessed likelihood of falling asleep in certain scenarios. A score of sixteen or higher shows that you are very sleepy during the day.
Assess your sleep apnea risk with
STOP-Bang questionnaire
The STOP-Bang questionnaire [2] is the favored screening tool in the medical profession [3]. It is straightforward, highly effective and considers more than tiredness alone. It is a set of eight questions with yes/no answers in a handy acronym, where each letter refers to a sleep apnea risk factor:
- S – snoring
- T – tired
- O – observed breathing cessation during sleep
- P – pressure, specifically high blood pressure
- B – body mass index greater than 35
- A – age
- N – neck size
- G – gender
Assess your sleep apnea risk with the STOP-Bang questionnaire
Berlin questionnaire
Similar to the STOP-Bang questionnaire, the Berlin questionnaire looks at several factors but clusters them into three categories [3]:
- Snoring – frequency, volume and observed apnea
- Tiredness – fatigue after sleep, tiredness throughout the day, sleeping whilst driving
- Cardiovascular fitness – blood pressure and BMI
If for two or more of these categories, you score two or above, you are at high risk of sleep apnea.
Diagnosis – sleep studies
Despite there being some prominent indicators of sleep apnea, getting reliably diagnosed means undergoing a sleep study.
The Apnea-Hypopnea Index (AHI)
It is the purpose of a sleep study is to identify and quantify sleep apnea, giving you a severity score. This score depends on how many times you experience the characteristic low-oxygen events. The apnea-hypopnea index (AHI) is this measurement [4], counting how many times you experience apnea or hypopnea in an hour:
- Apnea episode – complete airflow blockage for at least ten seconds.
- Hypopnea episode – at least 50% reduction in airflow for at least ten seconds.
Your AHI score relates to the severity of sleep apnea which is helpful when deciding how to treat it:
- 0-5 events per hour – normal
- 5-15 events per hour – mild sleep apnea
- 15-30 events per hour – moderate sleep apnea
- 30+ events per hour – severe sleep apnea
Polysomnography at a sleep clinic
Because snoring sound alone is not a reliable indicator of sleep apnea, other qualities need measuring too. This is done via a procedure is called polysomnography (poly = many, somnus = sleep, graph = drawing/measurements) and is usually conducted by a trained professional at a sleep clinic.
Sleep might not seem likely once you have been wired up and attached to the various monitors. But by observing eye movements, brain activity, muscle activation, airflow, oxygen levels and heart rate, you can construct a detailed image of what is happening to your body whilst you sleep, and gain insight into your sleep apnea.
What happens in a sleep study
Home tests
Although they are reliable, polysomnography tests in sleep clinics are impractical and expensive. Further, if you are lucky enough to get a referral for one, you’re likely to be waiting a while. Smaller scale tests done at home are therefore increasing in popularity.
Home testing uses portable devices with fewer parts, but importantly with enough measurements to get a good picture of your sleep apnea. Generally, they consist of:
- Chest strap – monitors heart rate and chest expansion
- Finger clamp sensor – uses infra-red to examine blood oxygen through your finger nail
- Nasal tube – tracks your breathing
- Audio unit – listens to your snoring patterns
If you are deemed to be at risk of sleep apnea, these kits can be supplied by your doctor. After performing the test at home, you return the kit for the results to be analyzed and a score to be generated.
Read Susan’s story, a SnoreLab user’s account of having a home sleep study to diagnose her severe obstructive sleep apnea.
Treating sleep apnea
The steps you take to improve your sleep apnea depend on the severity of your condition. If you suffer from mild to moderate sleep apnea, the techniques and consumer remedies you use to reduce normal snoring can still be very effective. Similar to so many other health issues, weight loss cannot be recommended enough.
If your condition is at the severe end of the scale, you are likely to be prescribed a device that keeps your airways open at night. This is called CPAP which stands for “continuous positive airway pressure”.
The device consists of a mask you fit over your face and an attached unit that draws in air. By introducing air into your throat and increasing air pressure, the soft parts of your throat are prevented from collapsing and causing obstruction.
With SnoreLab’s insights, you can read about the different types of CPAP mask and solving common issues with CPAP.
Conclusion
If you’re a loud snorer and find yourself feeling sleepy throughout the day, you may be suffering from sleep apnea without even knowing it. Being aware of the signs and using questionnaires is useful to assess your risk, after which it might be a good idea to present to your doctor.
With in-depth sleep studies that can be done at a specialist clinic or at home, you make that important step away from the masses of un-diagnosed people to become someone who understands their condition and knows what to do about it.