Breathing-Related Sleep Disorders

Breathing-related sleep disorders are conditions characterized by abnormal respiration during sleep, leading to disrupted sleep, daytime fatigue, and other health complications. These disorders are classified in the *DSM-5* and *International Classification of Sleep Disorders (ICSD-3)*.

Major Types of Breathing-Related Sleep Disorders

1. Obstructive Sleep Apnea (OSA) – Most Common

  • Definition: Repeated episodes of partial (hypopnea) or complete (apnea) upper airway obstruction during sleep.
  • Key Symptoms:
    • Loud snoring, gasping/choking at night.
    • Excessive daytime sleepiness (EDS).
    • Morning headaches, dry mouth.
    • Witnessed breathing pauses (reported by bed partner).
  • Risk Factors:
    • Obesity, male sex, older age.
    • Anatomical factors (e.g., enlarged tonsils, recessed jaw).
    • Alcohol/sedative use (relaxes throat muscles).
  • Complications:
    • Hypertension, heart disease, stroke.
    • Cognitive impairment, mood disorders (depression, anxiety).

2. Central Sleep Apnea (CSA)

  • Definition: Brain fails to send proper signals to breathing muscles, causing pauses in breathing.
  • Key Symptoms:
    • Episodes of stopped breathing (without snoring).
    • Frequent awakenings, insomnia.
    • Shortness of breath upon waking.
  • Causes/Subtypes:
    • Cheyne-Stokes Breathing (common in heart failure).
    • Drug-Induced CSA (e.g., opioids).
    • High-Altitude Periodic Breathing.
  • Complications:
    • Worsening heart failure, arrhythmias.

3. Sleep-Related Hypoventilation Disorders

  • Definition: Inadequate breathing leading to elevated CO₂ levels during sleep.
  • Types:
    • Obesity Hypoventilation Syndrome (OHS) – Occurs in obese individuals.
    • Neuromuscular Disorders (e.g., ALS, muscular dystrophy).
    • Chronic Obstructive Pulmonary Disease (COPD)-Related Hypoventilation.
  • Symptoms:
    • Fatigue, morning confusion.
    • Bluish tint to skin (cyanosis) in severe cases.

4. Sleep-Related Hypoxemia Disorder

  • Definition: Low blood oxygen levels during sleep without apnea/hypoventilation.
  • Causes: Lung disease (e.g., COPD, interstitial lung disease).

Diagnosis

  • Polysomnography (Sleep Study):
    • Measures brain waves, oxygen levels, heart rate, breathing effort.
    • Determines Apnea-Hypopnea Index (AHI) (mild: 5-15, moderate: 15-30, severe: 30+).
  • Home Sleep Apnea Testing (HSAT): Simplified test for suspected OSA.

Treatment Options

1. Obstructive Sleep Apnea (OSA)

  • Continuous Positive Airway Pressure (CPAP):
    • Gold standard treatment – keeps airway open with pressurized air.
  • Oral Appliances: Mandibular advancement devices (for mild-moderate OSA).
  • Surgery:
    • Uvulopalatopharyngoplasty (UPPP), tonsillectomy, maxillomandibular advancement.
  • Lifestyle Changes:
    • Weight loss, avoiding alcohol/sedatives, positional therapy (side sleeping).

2. Central Sleep Apnea (CSA)

  • Adaptive Servo-Ventilation (ASV): Adjusts air pressure dynamically.
  • Bilevel Positive Airway Pressure (BiPAP): Different pressures for inhalation/exhalation.
  • Treat Underlying Cause:
    • Heart failure management, opioid reduction.

3. Hypoventilation & Hypoxemia Disorders

  • Non-Invasive Ventilation (NIV): BiPAP with backup rate.
  • Supplemental Oxygen: For chronic hypoxemia.

When to See a Doctor

  • Loud snoring + daytime fatigue.
  • Witnessed breathing pauses during sleep.
  • Unexplained morning headaches or memory problems.
  • Known heart/lung disease with poor sleep.