Description

• Disorder characterized by cessation of breathing during sleep:
  • Defined as apneic episodes >10 s with brief EEG arousals or >3% oxygenation desaturation
• Risk factors:
  • Anatomic factors:
    • Micrognathia, retrognathia
    • Mandibular hypoplasia
    • Adenoid and tonsillar hypertrophy
    • Inferior displacement of the hyoid
  • Nonanatomic factors:
    • Central fat distribution/obesity (strongest risk factor)
    • Male >40 yr of age
    • Myxedema (hypothyroidism)
    • Alcohol/sedative use or use disorder
  • Smoking
• Associated illness:
  • Various dysrhythmias, particularly atrial fibrillation and bradyarrhythmia
  • Right and left heart failure
  • MI
  • Stroke
  • Motor vehicle accidents
  • Hypertension poorly controlled by medical therapies

Epidemiology

• Affects about 15% of males and 5% of females
• Prevalence has increased due to higher rates of obesity
• 80% of moderate or severe cases undiagnosed in middle-aged adults

Etiology

3 classifications of sleep apnea:

• Obstructive (84%) is due to upper airway closure despite intact respiratory drive:
  • Also known as Pickwickian syndrome
  • Pharyngeal airway is narrowed
• Central (0.4%) is due to lack of respiratory effort despite patent upper airway
• Complex (15%) is due to a combination of obstructive and central sleep apnea