Obstructive sleep apnea (OSA) is a sleep-related breathing disorder portrayed by interactions and cessation of breathing during sleep, often accompanied by gasping, choking and loud snoring. OSA is caused by the obstructions in the airflow while sleeping. An apnea is complete, while a hypopnea is a partial cessation of airflow. Less air coming to the lungs means less oxygen in your body and your blood flow.
The tissue and muscles within the upper airway relax and lose some tension, which makes it harder to keep the airways open. OSA is often accompanied by loud snoring, which happens when the air goes through narrower airways, and relaxed tissue vibrates.
If not treated right, obstructive sleep apnea can lead to hypertension, heart disease, stroke, and diabetes. Proper diagnosis and treatment are vital for preventing severe complications.
Obstructive Sleep Apnea – Symptoms
OSA shares some symptoms with other breathing-related sleep disorders, such as central sleep apnea and mixed or complex sleep apnea. Most common warning signs are:
- Loud snoring occurring virtually every night
- Excessive daytime sleepiness
- Episodes of waking up during the night gasping for air or chocking
- Pauses in breathing noticed by your bed partner
- Dry mouth and sore throat in the mornings
- Sweating during the night
- Morning headaches
- Weight gain
- Elevated blood pressure
- Reduced libido and impotence
- Problems with concentration and memory
- Mood changes and depression
Symptoms of OSA get worse during the winter, which can be caused by the weight gain that usually happens during this season. Seasonal allergies can cause nasal congestion and make OSA symptoms even worse. Weather conditions such as atmospheric pressure, humidity and carbon monoxide can all vary depending on the season or the place you are living. Cold and flu seasons are more common during the winter months, and with increased respiratory irritations and infections, the OSA symptoms get worse as well.
Recognizing obstructive sleep apnea in children may be a little harder, as signs are not as visible and can include:
- Sweating a lot during the night
- Chocking or drooling
- Learning and behavioral problems at school
- Sleepiness that is often misinterpreted as laziness
- Restlessness in bed
- Teeth grinding
- Pauses or absence of breathing
- Unusual sleep positions
If you have noticed your child experiencing some of these symptoms, it is best to talk to your doctor, as they can be a signal of many other conditions as well. Doctors will be able to asses the situation accurately and give your child the right treatment.
Obstructive Sleep Apnea – Causes
OSA usually occurs when the muscles in your throat relax too much to allow normal breathing. When your muscles relax, airway narrows as you breath in, and breathing may be inadequate for the next 10 to 20 seconds. That can lower the level of oxygen in your blood and can cause a buildup of carbon dioxide.
Your brain notices that something isn’t alright, and it briefly wakes you up from sleep so you can reopen your airway. This is usually brief, and you won’t remember it.
Your body tries to compensate for the insufficient levels of oxygen by contracting chest muscles and diaphragm more, and also by increasing heart rate and blood pressure, which can lead to many complications in the long run.
You may wake up with short breath or gasping for air, but it usually takes one or two deep breaths to correct this. This pattern can happen just a few times a night, or it can repeat itself more than a hundred times. If these interruptions occur less than five times every hour, it is considered normal.
Mild OSA – A person experiences 5-14 of these episodes every hour.
Moderate OSA – A person experiences 15-30 of these episodes every hour.
Severe OSA – A person experiences more than 30 of these episodes every hour.
Obstructive Sleep Apnea – Risk Factors
Everybody can develop sleep apnea, but certain people are more at risk. OSA is ubiquitous, and it is estimated that it affects millions of people in the US. Men are more likely to suffer from it than women, and it usually happens in the middle-aged men. Nearly 20% of men and 9% of women experience sleep apnea at some point in their lives.
In the 90s, only 3% of people were estimated to have sleep apnea. Experts attribute this rise in OSA to better diagnosis and increased obesity rates.
People who are overweight or obese are much more likely to develop OSA, as around half the people with sleep apnea are overweight. Excess fat and tissue in the throat may obstruct breathing, and being overweight is the number one cause for obstructive sleep apnea. Other risk factors include:
- Neck circumference and size: 17 inches and more for men, and 16 inches and more for women pose a risk factor.
- Sex: Males are two to three times more likely to develop OSA, which can be attributed to larger neck sizes and more common obesity problems.
- Age: The risk of developing obstructive sleep apnea increases with age, and it’s the highest in people aged between 40 and 60 years old. After then, the prevalence decreases.
- Pregnancy: Pregnant women are much more likely to suffer from OSA.
- A family history of sleep apnea: If you have a family member suffering from OSA, you are more at risk to develop it as well. That implies that there are some genetic factors behind it.
- Narrowed airway: Some people have naturally narrower airways. This can be due to enlarged tonsils and adenoids, or due to a bigger than normal tongue blocking the airway.
- Retrognathia: It’s a medical term for when your lower jaw is smaller than your upper one.
- High blood pressure, diabetes and heart disease: They are all linked with obesity, and they increase a chance of OSA as well.
- Asthma and allergies: Both are linked with an increased chance of developing OSA, as congestion additionally blocks airways.
- Opioids: Alcohol relaxes muscles, and that affects throat muscles as well. Cigarettes irritate your throat, lungs, and esophagus, causing fluid retention in the airways, and increasing chances for developing obstructive sleep apnea.
Obstructive Sleep Apnea – Diagnosis
There are two ways in which sleep professionals will conduct their research to determine whether you are suffering from obstructive sleep apnea.
An Overnight Lab Test
An overnight lab check provides extensive information about your sleep that will later be reviewed by a sleep physician. A test is called polysomnogram, and it requires you to stay overnight in a hospital or sleep center. The test lasts the whole night, and the sleep technician will use machines to determine the cause of your sleep problems:
- Electroencephalogram (EEG) – measures your brain waves
- Electro-oculogram (EOG) – measures your eye movement
- Electromyogram (EMG) – measures muscles activity
- Electrocardiogram (EKG or ECG) – measures heart rate and rhythm
- Pulse oximetry test – measures in your blood oxygen levels
- Arterial blood gas analysis (ABG)
Sleep technicians will also closely observe your breathing patterns and respiratory events such as apnea and hypopnea, as well as snoring. A polysomnogram is used for people who already have medical histories of sleep apnea and other sleep-related breathing conditions. The tests will give them enough information to precise asses your situation and give you the right treatment.
This study is conducted at the patients’ home, and there is no need for an overnight stay at the hospital or a sleep facility. At-home tests are not as thorough as a lab test, but they can give sleep physicians enough data needed for a right obstructive sleep apnea diagnosis. This test is usually used for people who don’t have complicated medical histories and have a lower risk of developing sleep apnea.
After the conducted sleep study, a sleep physician reviews the information and makes a diagnosis. They use the Apnea-Hypopnea Index (AHI) to quantify the results.
The AHI represents the number of apneas and hypopneas on average during one hour. An AHI below five is considered within the normal parameters. AHI between 5-15 is typical for mild sleep apnea. Moderate sleep apnea falls between the AHI of 15-30 while the severe OSA has AHI of 30 or more.
Obstructive Sleep Apnea – Treatment
OSA has many different treatment options that include lifestyle changes and other therapies. Lifestyle changes include:
- Weight loss, which also benefits overall health, so it is recommended combined with every other treatment.
- Avoiding alcohol, cigarettes or sleeping pills.
- Side sleeping, as opposed to back sleeping.
- Nasal sprays in case congestion problems are making it harder for you to breathe during the night.
Continuous positive airway pressure (CPAP) is usually the first choice for treating obstructive sleep apnea. In CPAP therapy, there is usually a machine placed beside your bed, and it’s generating a positive flow of continuous air pressure. It connects to a mask that you need to wear during the night. The constant stream of positive air pressure is keeping your airways open thus preventing or reducing breathing interruptions during your sleep.
Masks come in a variety of styles and sizes so that you can get the one best suited for your needs. There are nasal masks, nasal pillow as well as full face masks. Nasal ones go over your nose, nasal pillows rest inside your nostrils, while full face masks go over your nose and mouth. Machines come with a built-in humidifier that prevents the air from drying while you are using the device.
Bilevel positive airway pressure (BiPAP) is an alternative to CPAP therapy. BiPAP uses two different flow pressures rather than one continuous flow like CPAP. It is beneficial for people who have some troubles breathing against a set pressure, BiPAP machines allow users to exhale to a lower pressure and inhale with the higher set pressure. BiPAP therapy is highly effective for treating sleep-related breathing disorders.
Dental devices or mandibular advancement devices are other options for treating people with mild obstructive sleep apnea. They resemble mouthguard and are custom made by a dentist or orthodontist, to fit a specific person. They usually serve to align the lower jaw, rather than keep the airways open, and thanks to them, it is not possible for the tongue to block the throat.
Surgery is available, and it usually comes into play when the other treatments haven’t worked, or they haven’t had the desired effect. The operation is often the best option for those who have additional or a misshapen tissue, as these can block the airflow. That is the case for people with enlarged tonsils, adenoids, a deviated nasal septum, or a smaller lower jaw, causing the narrowing of the throat.
There are several types of surgeries available:
- Upper air stimulator is the device that has a small generating pulse that stimulates the neurons to control your throat muscles and keep them open.
- Somnoplasty uses radiofrequency energy to tighten the palate of your throat.
- UPPP (uvulopalatopharyngoplasty) is a surgical procedure that removes the relaxed, soft tissue at the back of your throat. That increases the width of the airway, allowing more air to come to your lungs.
- Nasal surgery is used to correct the deviations in the nose, such as deviated septum.
- Mandibular/maxillary advancement surgery is done when the situation is so bad that oral devices can’t help correct the situation. Surgeons move the face and the jaw bones forward so that there is more room at the back of your throat. It is a last resort option for people with severe obstructive sleep apnea, and those with some problems with their face and head.
Although drugs can’t be used to treat sleep-related breathing disorders directly, they can be used to address some of the causes of obstructive sleep apnea. Melatonin supplements have shown some benefits while treating people with obstructive sleep apnea, and they can be used in combination with other available treatments.
Dusan is a biologist, a science enthusiast and a huge nature lover. He loves to keep up to date with all the new research and write accurate science-based articles. When he’s not writing or reading, you can find him in the kitchen, trying out new delicious recipes; out in the wild, enjoying the nature or sleeping in his bed.