Sleep Apnea

G. Surya Thejaswi
Clinical Research Associate
MV Hospital for Diabetes & Research Centre
Royapuram

DEFINITION

Sleep apnea is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing, during sleep. Each pause in breathing, called an apnea, can last from a few seconds to minutes, and may occur 5 to 30 times or more an hour. Similarly, each abnormally low breathing event is called a hypopnea.

Sleep apnea is diagnosed with an overnight sleep test called a polysomnogram, or "sleep study".


TYPES OF SLEEP APNEA

* Obstructive sleep apnea is the most common type of sleep apnea. It occurs when the soft tissue in the back of your throat relaxes during sleep, causing a blockage of the airway (as well as loud snoring).


* Central sleep apnea is a much less common type of sleep apnea that involves the central nervous system, rather than an airway obstruction. It occurs when the brain fails to signal the muscles that control breathing. People with central sleep apnea seldom snore.

* Complex/Mixed sleep apnea is a combination of obstructive sleep apnea and central sleep apnea.

ANATOMY OF A SLEEP APNEA EPISODE

As air flow stops during a sleep apnea episode, the oxygen level in your blood drops. Your brain responds by briefly disturbing your sleep enough to kick start breathing—which often resumes with a gasp or a choking sound. If you have obstructive sleep apnea, you probably won’t remember these awakenings. Most of the time, you’ll stir just enough to tighten your throat muscles and open your windpipe. In central sleep apnea, you may be conscious of your awakenings.

SLEEP APNEA SIGNS AND SYMPTOMS:

Major signs and symptoms of sleep apnea

* Loud and chronic snoring
* Choking, snorting, or gasping during sleep
* Long pauses in breathing
* Daytime sleepiness, no matter how much time you spend in bed

Other common signs and symptoms of sleep apnea include:

* Waking up with a dry mouth or sore throat
* Morning headaches
* Restless or fitful sleep
* Insomnia or nighttime awakenings
* Going to the bathroom frequently during the night
* Waking up feeling out of breath
* Forgetfulness and difficulty concentrating
* Moodiness, irritability, or depression

Signs and symptoms of sleep apnea in children

While obstructive sleep apnea can be common in children, it’s not always easy to recognize. In addition to continuous loud snoring, children with sleep apnea may adopt strange sleeping positions and suffer from bedwetting, excessive perspiration at night, or night terrors. Children with sleep apnea may also exhibit changes in their daytime behavior, such as:

* Hyperactivity or inattention
* Developmental and growth problems
* Decrease in school performance
* Irritable, angry, or hostile behavior
* Breathing through mouth instead of nose

Is it just snoring or is it sleep apnea?

Not everyone who snores has sleep apnea, and not everyone who has sleep apnea snores. So how do you tell the difference between garden variety snoring and a more serious case of sleep apnea?

The biggest telltale sign is how you feel during the day. Normal snoring doesn’t interfere with the quality of your sleep as much as sleep apnea does, so you’re less likely to suffer from extreme fatigue and sleepiness during the day.

SLEEP APNEA CAUSES AND RISK FACTORS

Anyone can have sleep apnea-young, old, male, female, and even children can suffer. However, certain risk factors have been associated with obstructive and central sleep apnea.

Risk factors for obstructive sleep apnea

You have a higher risk for obstructive sleep apnea if you are:
* Overweight
* Male
* Related to someone who has sleep apnea
* Over the age of 65
* Black, Hispanic, or a Pacific Islander
* A smoker

Other risk factors for obstructive sleep apnea include certain physical attributes, such as having a thick neck, deviated septum, receding chin, or enlarged tonsils or adenoids (the most common cause of sleep apnea in children). Allergies or other medical conditions that cause to nasal congestion and blockage can also contribute to sleep apnea.

Risk factors for central sleep apnea

Like obstructive sleep apnea, central sleep apnea is more common in males and people over the age of 65. However, unlike obstructive sleep apnea, central sleep apnea is often associated with serious illness, such as heart disease, stroke, neurological disease, or spinal or brainstem injury.

COMPLICATIONS OF SLEEP APNEA:


Few facts:

* Obstructive Sleep Apnea (OSA) is the most common form of sleep-disordered breathing, accounting for over 80% of cases.
* Estimates suggest that up to 40% of people with OSA will have diabetes, but the incidence of new diabetes in people with OSA is not known.
* In people who have diabetes, the prevalence of OSA may be up to 23%, and the prevalence of some form of sleep disordered breathing may be as high as 58%.
* Overweight and obesity may play a role, but some recent studies show an association between the two conditions that is independent of overweight/ obesity.
* OSA may have effects on glycemic control in people with type 2 diabetes.
* OSA is associated with a range of cardiovascular complications such as hypertension, stroke and heart failure.



Possible mechanistic links between OSA, metabolic syndrome and diabetes mellitus

SELF-HELP TREATMENT OPTIONS FOR SLEEP APNEA

While a diagnosis of sleep apnea can be scary, it is a treatable condition. In fact, there are many things you can do on your own to help, particularly for mild to moderate sleep apnea. Home remedies and lifestyle modifications can go a long way in reducing sleep apnea symptoms.

Lifestyle changes that can help sleep apnea
* Lose weight. Some people find that even moderate to severe sleep apnea can be completely corrected by losing excess weight. For others, even a small amount of weight loss can open up the throat and improve sleep apnea symptoms.
* Quit smoking. Smoking is believed to contribute to sleep apnea by increasing inflammation and fluid retention in your throat and upper airway.
* Avoid alcohol, sleeping pills, and sedatives, especially before bedtime, because they relax the muscles in the throat and interfere with breathing.
* Avoid caffeine and heavy meals within two hours of going to bed.
* Maintain regular sleep hours. Sticking to a steady sleep schedule will help you relax and sleep better. Apnea episodes decrease when you get plenty of sleep.

MEDICAL TREATMENT OPTIONS FOR SLEEP APNEA


If your sleep apnea is moderate to severe, or you’ve tried self-help strategies and lifestyle changes without success, it’s important to see a sleep doctor. A sleep specialist can evaluate your symptoms and help you find an effective treatment.
Treatments for central and complex sleep apnea usually include:

* Treating the underlying medical condition causing the apnea, such as a heart or neuromuscular disorder.
* Using supplemental oxygen while you sleep.
* Breathing devices that are also used to manage obstructive sleep apnea.
Medications are only available to treat the sleepiness associated with sleep apnea, not the apnea itself, so should only be used in conjunction with other proven sleep apnea treatments.

CPAP for sleep apnea

Continuous Positive Airflow Pressure, or CPAP for short, is the most common treatment for moderate to severe obstructive sleep apnea. In many cases, you’ll experience immediate symptom relief and a huge boost in your mental and physical energy. The CPAP device is a mask-like machine that provides a constant stream of air which keeps your breathing passages open while you sleep. Most CPAP devices are the size of a tissue box.

If you’ve given up on sleep apnea machines in the past because of discomfort, you owe it to yourself to give them a second look. CPAP technology is constantly being updated and improved. The new CPAP devices are lighter, quieter, and more comfortable, so make sure your sleep apnea device is up to date.


Other breathing devices for sleep apnea

In addition to CPAP, there are other adjustable airway pressure devices that a sleep specialist may recommend:

* Bilevel positive airway pressure (BPAP) devices can be used for those who are unable to adapt to using CPAP, or for central sleep apnea sufferers who need assistance for a weak breathing pattern. This device automatically adjusts the pressure while you're sleeping, providing more pressure when you inhale, less when you exhale. Some BPAP devices will also automatically deliver a breath if it detects you haven't taken one for a certain number of seconds.
* Adaptive servo-ventilation (ASV) can be used for treating central sleep apnea as well as obstructive sleep apnea. The device stores information about your normal breathing pattern and automatically uses airflow pressure to prevent pauses in your breathing while you’re asleep.

DENTAL DEVICES AND SURGERY FOR SLEEP APNEA

If you’ve tried CPAP and self-help tips and your sleep apnea persists, you may benefit from a dental device or surgical treatment.

Dental devices for sleep apnea

Two common oral devices are the mandibular repositioning device and the tongue retaining device. These devices open your airway by bringing your lower jaw or your tongue forward during sleep. Dental devices are only effective for mild to moderate sleep apnea.

Surgery as treatment for sleep apnea

If you have exhausted other apnea treatment options, you may want to discuss surgical options with your doctor or sleep specialist. Surgery can increase the size of your airway, thus reducing your episodes of sleep apnea.

The surgeon may remove tonsils, adenoids, or excess tissue at the back of the throat or inside the nose. Or, the surgeon may reconstruct the jaw to enlarge the upper airway. Surgery carries risks of complications and infections, and in some rare cases, symptoms can become worse after surgery.