What is the appropriate workup for a healthy 17-year-old male with 6 months of fatigue and excessive sleepiness?

Workup for Fatigue and Excessive Sleepiness in a 17-Year-Old Male

A comprehensive sleep study (polysomnography followed by multiple sleep latency test) is the most appropriate next step in the workup of a healthy 17-year-old male with 6 months of fatigue and excessive sleepiness. 1

Initial Evaluation

History

• Establish onset, frequency, and duration of sleepiness and any remission periods
• Assess duration of nighttime sleep
• Screen for symptoms of specific sleep disorders:
  • Narcolepsy: cataplexy (muscle weakness triggered by emotions), hypnagogic hallucinations, sleep paralysis
  • Obstructive sleep apnea: observed apneas, snoring
  • Restless legs syndrome: uncomfortable sensations/urge to move legs, worse at night
• Review medical, neurologic, and psychiatric conditions
• Medication and substance use assessment (including recreational drugs and alcohol)

Screening Tools

• Epworth Sleepiness Scale (ESS) to quantify sleepiness severity
• Sleep diary to document sleep-wake patterns
• STOP questionnaire if OSA is suspected

Laboratory Testing

1. Basic bloodwork to rule out medical causes:

   • Thyroid stimulating hormone (TSH)
   • Complete blood count (CBC)
   • Comprehensive metabolic panel
   • Ferritin levels (especially if restless legs symptoms present; levels <45-50 ng/mL indicate treatable cause) 1

2. Sleep studies:

   • Overnight polysomnography (PSG) followed by multiple sleep latency test (MSLT) 1
   • MSLT involves 4-5 daytime naps at 2-hour intervals to assess:
     • Sleep latency (time to fall asleep)
     • Presence of REM sleep (≥2 naps with REM sleep suggests narcolepsy)

3. Brain imaging:

   • MRI of the brain if neurological causes are suspected (e.g., tumors, multiple sclerosis) 1

Differential Diagnosis

Primary Sleep Disorders

• Narcolepsy (with or without cataplexy)
• Idiopathic hypersomnia
• Obstructive sleep apnea
• Insufficient sleep syndrome (chronic sleep deprivation)
• Restless legs syndrome

Secondary Causes

• Medical conditions (hypothyroidism, anemia)
• Psychiatric disorders (depression, anxiety)
• Medication side effects
• Substance use (including caffeine withdrawal)

Management Approach

Management will depend on the specific diagnosis but generally includes:

1. Sleep hygiene education:

   • Regular sleep-wake schedule
   • Avoiding heavy meals, alcohol, and nicotine near bedtime
   • Creating a dark, quiet, comfortable sleep environment
   • Regular exercise (but not close to bedtime)

2. Disorder-specific treatments:

   • Narcolepsy: modafinil, stimulants, sodium oxybate
   • OSA: continuous positive airway pressure (CPAP)
   • Restless legs syndrome: dopamine agonists, gabapentin
   • Idiopathic hypersomnia: modafinil, lifestyle modifications

3. Behavioral modifications:

   • Scheduled short naps (15-20 minutes) may help manage sleepiness
   • Regular physical activity
   • Avoiding shift work or jobs requiring sustained attention for long periods

Important Considerations

• Distinguish between fatigue and sleepiness - they are different symptoms that may coexist but require different approaches 2
• Excessive daytime sleepiness significantly impacts quality of life, cognitive function, and safety 3
• Untreated sleep disorders can lead to poor academic performance, mood disorders, and increased risk of accidents
• In adolescents, consider the impact of school schedules, social media use, and screen time on sleep patterns

The workup should be thorough as sleep disorders in young people are often underdiagnosed but highly treatable, with significant improvements in quality of life possible with appropriate intervention.