Snoring Sleep Related Breathing Disorders
Sleep Related Breathing Disorders (SRBDs) is a term used to describe a spectrum of disorders related to increased airway resistance during sleep where breathing is repeatedly interrupted. There are several different types of sleep disordered breathing disorders with varying degrees of severity.
Snoring is a very common condition and a symptom of obstructive sleep apnea (OSA). It is associated with changes in the caliber of the upper airway. This results in vibration of the soft tissue of the palate and creates snoring.
Not everybody who snores has OSA, and not everybody who has OSA snores. Snoring indicates that there is some resistance to the normal path of air from the outside of the lungs, and snoring can be associated with disrupted sleep, daytime fatigue and sleepiness. Snoring can also be extremely disruptive to the sleep of the bed partner and can stress interpersonal relationships of couples.
There are several surgical procedures that can improve snoring, some of which can be performed on an outpatient basis and that involve reducing the excess volume of tissue in the airway that produces snoring. Oral appliances, which are very similar to mouth guards or retainers which are placed in the mouth during sleep to either move the lower jaw or tongue forward, can also improve snoring. Your physician can discuss other options that are also available.
Upper Airway Resistance Syndrome (UARS)
Upper Airway Resistance Syndrome (UARS) is very similar to OSA in that the soft tissue of the throat relaxes, reduces the size of the airway, and results in disturbed sleep and consequent daytime impairment, including excessive daytime sleepiness. Although the increase in upper airway resistance is not enough to meet criteria of the sleep disordered breathing that define obstructive sleep apnea, the resulting increase in breathing effort does cause a brief awaking from sleep that is often undetected by the individual. When this scenario repeats throughout the night, sleep is impaired, just like in obstructive sleep apnea.
The symptoms of UARS tend to be similar to OSA but may be less in severity. People with UARS usually complain of snoring, daytime sleepiness, cognitive impairment, un-refreshing sleep and frequent arousals from sleep.
Continuous Positive Airway Pressure (CPAP) is the most effective treatment for sleep apnea; however there are also surgical options, oral appliances, and behavioral approaches that can be used to treat OSA. Weight loss, although always a good idea in reducing obesity-related conditions (e.g. hypertension, diabetes), is considered supplementary or adjunctive therapy rather than primary treatment for OSA. Other underlying medical conditions, especially nasal allergies, should also be treated. A nasal steroid or nasal antihistamine might help improve nasal obstructive associated with allergies as well as the OSA symptoms. The same treatments that are successful for OSA can be used to treat UARS. Treatments such as surgery, oral appliances, positional therapy (restricting the individual to sleeping on his/her side), and weight loss may be effective in improving sleep disordered breathing in individuals with UARS. CPAP is generally not used for UARS.
Obstructive Sleep Apnea (OSA)
Obstructive Sleep Apnea occurs when the airway completely or partially collapses repeatedly throughout the night. During sleep, the soft tissues in the throat relax. For someone with OSA, these tissues can block the upper airway enough to disrupt sleep related breathing.
When the airway is blocked, the oxygen levels in the body drop causing the person to wake up long enough to begin breathing normally again. These awakenings are often very brief, sometimes only a few seconds and this is the reason that the affected individual is often not aware that they have these awakenings during sleep. This pattern repeats during the night, and someone with severe sleep apnea may wake up hundreds of times each night. Even though the awakenings are usually very short, they fragment and interrupt the sleep cycle. This sleep fragmentation can cause significant levels of daytime fatigue and sleepiness, which are common symptoms of sleep apnea.
There are 3 types of obstructive breathing events:
- Apnea: A period of at least 10 seconds during which there is a complete or near complete pause in breathing.
- Hypopnea: A decrease in airflow lasting at least 10 seconds.
- Respiratory Effort Related Arousal (RERA): A limitation in breathing that results in increases respiratory effort and culminates in an arousal; it does not meet the criteria from an apnea or hypopnea.
OSA is estimated to occur in approximately 18 million Americans; a quarter of men and one-tenth of women between the ages of 30 and 60 years have sleep study evidence of OSA. It is a treatable disease; however, if left untreated, it is associated with serious medical conditions.
Risk Factors of OSA include:
- Obesity. The extra tissue caused by fat deposits around the throat, chest and abdomen create extra resistance which can hamper breathing. However, just because someone is overweight does not mean they have OSA. The opposite is true: many thin people have OSA.
- Large Neck Size. A thick neck can narrow the airway, and increase the likelihood of OSA. Higher risk of OSA is associated with a neck circumference greater than 17 inches (43 centimeters) for men and 15 inches (38 centimeters) for women.
- Narrowed Upper Airway. A small jaw or enlarged tongue can narrow the upper airway and predispose individuals toward the development of OSA. Enlarged tonsils and/or adenoids can also restrict the size of the upper airway.
- Positive OSA Family History. If you have family members with sleep apnea, you may be at increased risk. Like eye color, the shape and size of the airway and cranial facial features may be inherited from our parents and can have an impact on the likelihood of developing OSA.
- Old Age, Male Gender, Post-Menopausal Women, and Minorities. OSA is more common in adults over the age of 65 years, men, post-menopausal women, and among those under the age of 35 years, some minority groups.
- Smoking and Use of Alcohol or Tranquilizers. Smokers are nearly three times more likely to have OSA and alcohol or tranquilizers can relax the muscles in your upper airway and predispose it to collapse.
- High Blood Pressure (hypertension) and Diabetes. OSA is more likely in people who have hypertension and up to three times more common in those with diabetes.
- Chronic Nasal Congestion. OSA occurs twice as often in those with consistent nasal congestion at night, regardless of cause.
A typical OSA patient is a middle aged, obese male; however anyone can develop OSA, and symptoms can vary from person-to-person, increase with age, and have different levels of severity. Common symptoms of OSA in adults may include:
- Snoring (usually loud and disruptive)
- Choking or gasping during sleep
- Observed pauses in breathing
- Daytime fatigue and/or sleepiness
- Dry mouth/sore throat in morning
- Morning headaches
- Night sweats
- Poor concentration and attention
- Memory Problems
- Sleep walking or night terrors.
Other Sleep Related Respiratory Conditions
Other sleep related respiratory conditions include such disorders such as Central Sleep Apnea (CSA) and Sleep Related Hypoventilation/Hypoxemic Syndromes. CSA occurs when you repeatedly stop breathing during sleep because your brain does not cue your body to breathe. This differs from Obstructive Sleep Apnea since in CSA there is no breathing effort because there is no drive to breathe. In its primary form, CSA is the result of instability of the breathing control system as the individual transitions from wakefulness to sleep. Sleep Related Hypoventilation/Hypoxemic Syndromes may be the result of a decreased response to low oxygen or high carbon dioxide during wakefulness and sleep and are characterized by frequent episodes of shallow breathing lasting longer than 10 seconds during sleep
Treating Other Conditions
Continuous Positive Airway Pressure (CPAP) is typically ineffective at resolving these conditions though Bilevel Airway Pressure (BiPAP) or Auto Servo-ventilation (ASV) devices may help to normalize sleep related breathing in patients with Central Sleep Apnea or Sleep Related Hypoventilation/Hypoxemic Syndromes.
A comprehensive history and physical examination by a sleep physician followed by an overnight sleep study or polysomnogram is absolutely necessary to diagnose a sleep related breathing disorder in children or adults.
Based on the results of the overnight sleep study, your sleep physician will be able to determine whether or not you have a sleep related breathing disorder that warrants treatment.
To learn more about the sleep diagnostic tests, visit the Tests Section.