There are 3 types of sleep apnea:
Central Apnea - caused by a failure of the brain to activate the muscles of breathing during sleep.
Obstructive Sleep Apnea (OSA) - caused by a collapse of the airway during sleep.
Mixed Apnea- a combination of central and OSA.
If interruptions in breathing (apnea) occur 15 or more times per hour the individual has significant sleep apnea. A normal Apnea Hypo Apnea Index (AHI) is < 5. A AHI of 5-15 is mild OSA, 15 to 30 is moderate OSA and > 30 apneic episode per hour is severe OSA.
Risk Factors for OSA include:
Increasing age (common among adults, rare in children)
More common in men than in pre-menopausal women, but the prevalence in post-menopausal women is about the same as men of same age.
Central/truncal obesity
Large neck size (> 17 inches in men and > 16 inches in women)
A large tongue that obstructs the airway
Smoking
Use of alcohol or other Central Nervous System (CNS) depressant drugs, sedatives and muscle relaxants.
Short-term OSA
Short-term OSA may be the result of upper airway infections, nasal congestion, swelling of the throat as in Infectious Mononucleosis and also in individuals with large tonsils. Here the apnea resolves once the underlying condition is treated.
Warning signs of OSA include:
Loud snoring
Excessive daytime sleepiness (fatigue), sleepy while driving
Apneic episodes witnessed by another person
Choking and gasping for air during sleep
Memory problems, irritability, anxiety and increasing depression.
Difficulty performing duties at work/home/school
Accidents on the job and /or Motor Vehicle Accidents (MVA).
Waking up due to acid reflux from the stomach- Gastro Esophageal Reflux Disease (GERD)
Morning headaches
Complications of OSA:
High Blood Pressure (hypertension)
Ischemic Heart Disease leading to heart attacks and stroke
Arrhythmias (irregular heartbeats)
Type 2 Diabetes Mellitus
Pulmonary Hypertension (elevated pressure in the blood vessels of the lungs) and Death.
Diagnosis of OSA:
Diagnosis is made by a careful history from patient and individual(s) who observe apneic episodes in the patient during sleep, and a careful physical examination. The gold standard test used to diagnose sleep apnea is an overnight polysomnogram(PSG) "sleep study". The polysomnogram can be performed either in a sleep laboratory or by Home Diagnostic Titration Testing (HDTT).
Treatment of OSA:
For mild to moderate cases of OSA, oral appliances may work; these can be made by a Dentist or Orthodontist. Upper airway surgery (on the soft palate) or nasal surgery (correction of nasal septum/rhinoplasty) may be recommended.
For Severe OSA the most common treatment is the use of CPAP therapy (Constant Positive Airway Pressure). The CPAP device is a small portable machine with a generator which delivers room air to the lungs at a positive pressure through a tubing via a full face mask worn every night during sleep.
For patients who find it difficult to sleep with a mask, a nasal pillow device can be substituted to increase compliance. If the CPAP pressure appears to be excessive bi-level therapy which uses a lower level of pressure can substituted.
RECOMMENDATIONS:
Behavior modification is the key to symptom improvement. Individuals should lose weight, engage in regular exercise, stop smoking, avoid sleeping on the back, avoid alcohol and sedating medications, treat any allergic/upper respiratory symptoms.
Summary: Even if symptoms improve with behavior therapy, individuals should not discontinue their CPAP therapy without consulting with their Health Care Provider. The only accurate and safe way to determine if an individual no longer has sleep apnea is to perform a repeat polysomnogram.
Author: Beverly Russell, MA, ANP-BC is an Adult Medicine Nurse Practitioner at Kaiser Los Angeles Medical Center. She works with the Bariatric Surgery Pre-operative/OPTIONS Program, and many of her patients have severe Obstructive Sleep Apnea (OSA). http://www.BeverlyRussellSeminars.com