Differential Diagnosis for Fatigue and Daytime Sleepiness

• Single Most Likely Diagnosis
  • Sleep Apnea: This condition is characterized by pauses in breathing during sleep, leading to fragmented sleep and excessive daytime sleepiness. It is a common cause of fatigue and daytime sleepiness, especially in overweight individuals or those with a large neck circumference.
• Other Likely Diagnoses
  • Insomnia: Difficulty initiating or maintaining sleep can lead to fatigue and daytime sleepiness. It is a common sleep disorder that can be caused by various factors, including stress, anxiety, or irregular sleep schedules.
  • Restless Leg Syndrome: This condition is characterized by an uncontrollable urge to move the legs, usually due to uncomfortable sensations. It can disrupt sleep and lead to fatigue and daytime sleepiness.
  • Hypothyroidism: An underactive thyroid gland can cause fatigue, sleepiness, and dry skin. It is a common endocrine disorder that can be diagnosed with a simple blood test.
  • Anemia: A decrease in red blood cells or hemoglobin can lead to fatigue, weakness, and shortness of breath. It is a common condition that can be caused by iron deficiency, vitamin deficiency, or chronic diseases.
• Do Not Miss Diagnoses
  • Sleep-Related Accidents or Injuries: Untreated sleep disorders can increase the risk of accidents or injuries, especially while driving or operating heavy machinery.
  • Narcolepsy: A neurological disorder that affects the brain's ability to regulate sleep-wake cycles. It can cause excessive daytime sleepiness, cataplexy, and sleep paralysis.
  • Obstructive Sleep Apnea with Cardiovascular Complications: Untreated sleep apnea can increase the risk of cardiovascular disease, including heart attacks, strokes, and high blood pressure.
  • Myasthenia Gravis: A rare autoimmune disorder that can cause muscle weakness, fatigue, and respiratory failure.
• Rare Diagnoses
  • Idiopathic Hypersomnia: A rare sleep disorder characterized by excessive daytime sleepiness and prolonged nighttime sleep.
  • Kleine-Levin Syndrome: A rare neurological disorder that causes recurring episodes of excessive daytime sleepiness and automatic behavior.
  • Prader-Willi Syndrome: A rare genetic disorder that causes excessive daytime sleepiness, obesity, and short stature.
  • Fatal Insomnia: A rare prion disease that causes gradual degeneration of the brain, leading to complete insomnia and eventually death.