People who experience excessive daytime sleepiness along with snoring, choking/gasping, episodes of not breathing or stopping breathing during sleep, or have high blood pressure would be considered high risk for having OSA. Other risk factors include obesity, large neck, male gender, and family history of OSA. If you have thought that you or your family/friend might have OSA, an evaluation by a Sleep Specialist should be done.
Obstructive Sleep Apnea
In order to diagnose OSA, it will take more than just having symptoms. There needs to be objective data evaluating your sleep, oxygen levels, airflow from your nose/mouth, breathing, and heart rate. There are a few very common questionnaires that your Provider might have you fill out when evaluating your sleep. One is called the STOP-BANG questionnaire and another is called the Epworth Sleepiness Scale (ESS).
- S (snoring)
- T (tired)
- O (observed apneas or stopping breathing episodes),
- P (high blood pressure)
- B (obesity, BMI >35)
- A (Age, >50 years old)
- N (neck circumference, >16 inches
- G (male gender)
1 point for each positive letter. A score of 5-8 is considered a high probability of moderate/severe OSA.
ESS: This is a series of questions asking your probability of dozing off in different situations;
- or high chance.
A score of >10 is considered excessive sleepiness.
After your Provider has decided that you need to have a sleep study, the next decision is to decide what study to do. There are 2 main sleep studies: in-laboratory polysomnography (PSG) and home sleep study (HST).
Which sleep study is right for you?
Typically patients who have cardiovascular disease (heart failure, uncontrolled cardiac arrhythmia), pulmonary disease (chronic obstructive pulmonary disease), neurological disorders (stroke, neuromuscular weakness), medications (chronic opioid use), or significant obesity (BMI >50, obesity hypoventilation syndrome) would be recommended to have an in-lab sleep study. This is because these patients could also suffer from central sleep apnea, which is a non-obstructive sleep-disordered breathing issue. This will be discussed in another post.
Those who would be considered high-risk for OSA without medical conditions can most likely due to an HST. Other factors that play a role in the decision-making include transportation, child/family care, cost, and insurance coverage. PSGs are considered the gold standard diagnostic test for OSA. If an HST is performed and is inconclusive, it is recommended to do a PSG for a more accurate study, especially if the clinical suspicion for OSA remains high. HST equipment can sometimes miss apneas, misdiagnose the type of apneas (obstructive vs central), and cannot monitor limb movements. All these parameters are important in the evaluation of someone’s sleep.
Types Of PSG
There are 3 types of PSGs: diagnostic only, split-night (diagnostic and therapeutic), and titration. PSGs will require you to sleep overnight in a sleep center. Typically, you arrive in the early evening. The sleep technician would then start to put several monitors on your body. Once you’re all connected, you are ready to sleep. There are quite a number of monitors: brain waves, eye movements, airflow from nose/mouth, chin muscle tone, chest movements, abdominal movements, oxygen levels, heart rate/rhythm, leg movements. (Should we have a picture?) Additionally, some people are anxious about sleeping in places other than their own beds. It would be a good idea to consider a sleep aid with your sleep study just in case. Your Sleep Provider would be able to prescribe this.
There are a few different types of HSTs. Some HST equipment is more traditional, monitoring airflow, chest movements, oxygen levels, heart rate. There is a new HST device called the WatchPAT. This device is unique in that it does not monitor airflow. All the monitoring is done by a sensor placed on your finger. The WatchPAT device can determine how many times you stop breathing, snoring, body position, heart rate, oxygen levels, sleep stages (REM vs Non-REM), and respirations. Some of these devices are one-time use and can be disposed of the next morning. This is super convenient.
Putting it Together
If you think you or a family/friend have OSA, a formal evaluation by a Sleep Specialist should be done. During the visit, the Provider will decide if a sleep study should be ordered and which type of sleep study would be the most appropriate. If OSA is present, it is likely that treatment would be recommended. Uncontrolled OSA is linked to an increased potential for developing cardiovascular disease. This will be discussed in another post.
I hope you find this helpful. Feel free to comment or leave a question. I hope you have a good night’s sleep!
-Twilight Sleep Doc