Obstructive sleep apnea (OSA) with snoring is related to several cardiovascular diseases. It is a cause of systemic hypertension.

Mild lung hypertension is also associated with OSA. Heart blockages are associated with severe OSA but not mild OSA. Night cardiac arrhythmias with OSA are known and therefore all patients with nocturnal cardiac arrhythmias should be evaluated for possible OSA. Treatment of OSA may reduce systemic blood pressure, lung pressure, cardiovascular events and eliminate nocturnal ventricular bradycardia and asystole in many patients with OSA.

The throat is surrounded by muscles that control the airway for speaking, swallowing and breathing. During sleep, these muscles are less active, and this causes the throat to narrow. In most people, this narrowing does not affect breathing. In others, it can cause snoring, sometimes with reduced or completely blocked airflow.

A completely blocked airway without airflow is called an obstructive apnea. Partial obstruction with diminished airflow is called a hypopnea. A person may have apnea and hypopnea during sleep.

Insufficient breathing due to apnea or hypopnea causes oxygen levels to fall and carbon dioxide to rise. Because the airway is blocked, breathing faster or harder does not help to improve oxygen levels until the airway is reopened. Typically, this requires the person to awaken to activate the upper airway muscles. Once the airway is opened, the person then takes several deep breaths to catch up on breathing. As the person awakens, he or she may move briefly, snort or snore, and take a deep breath. Less frequently, a person may awaken completely with a sensation of gasping, smothering, or choking.

Many people with sleep apnea are unaware of their abnormal breathing in sleep, and all patients underestimate how often their sleep is interrupted. Awakening from sleep causes sleep to be unrefreshing and causes fatigue and daytime sleepiness.

Symptoms of OSA

The main symptoms include loud snoring, fatigue, and daytime sleepiness. However, some people have no symptoms. Fatigue and sleepiness have many causes and are often attributed to overwork and increasing age.

Other symptoms may include one or more of the following:

  • Restless sleep
  • Awakening with choking, gasping, or smothering
  • Morning headaches, dry mouth or sore throat
  • Waking frequently to urinate
  • Awakening unrested, groggy
  • Memory impairment, difficulty concentrating, low energy

Certain factors increase the risk of sleep apnea.

  • Increasing age: Sleep apnea occurs at all ages, but it is more common in middle and older age adults.
  • Male sex: Sleep apnea is two times more common in men, especially in middle age.
  • Obesity: The more obese a person is, the more likely they are to have sleep apnea.
  • Sedation from medication or alcohol interferes with the ability to awaken from sleep and can lengthen periods of apnea (no breathing), with potentially dangerous consequences.
  • Abnormality of the airway

Complications of sleep apnea

  • Daytime sleepiness
  • Difficulty concentrating
  • Increased risk of accidents and errors in daily activities
  • More than twice as likely to be involved in a motor vehicle accident
  • Increased risk of cardiovascular problems such as high blood pressure, heart attack, abnormal heart rhythms, or stroke

Diagnosis of sleep apnea

  • A complaint of snoring and ineffective sleep
  • Neck size (greater than 17 inches in men or 16 inches in women) is associated with an increased risk of sleep apnea.
  • A small upper airway: Difficulty seeing the throat because of a tongue that is large for the mouth.
  • High blood pressure, especially if it is resistant to treatment
  • If a bed partner has observed the patient during episodes of stopped breathing (apnea), choking, or gasping during sleep, there is a good possibility of sleep apnea.