What is the diagnosis and treatment for a 20-60 year old night shift worker experiencing extreme fatigue, dizziness, and hypersomnia on days off, with difficulty functioning?

Shift Work Disorder: Diagnosis and Management

Diagnosis

This night shift worker has Shift Work Disorder (SWD), a circadian rhythm sleep disorder characterized by excessive sleepiness during work hours and difficulty functioning during scheduled wake times that occurs in approximately 30% of shift workers. 1, 2

Diagnostic Criteria

To confirm SWD, the following must be present:

• Excessive sleepiness or insomnia temporally associated with work periods occurring during habitual sleep phase 3
• Symptoms persist for at least 3 months 3
• No other medical or mental disorder accounts for the symptoms 3
• Symptoms do not meet criteria for other sleep disorders (e.g., obstructive sleep apnea, narcolepsy) 3

Essential Clinical Assessment

Obtain a detailed sleep history focusing on:

• Frequency and timing of symptoms in relation to work schedule 4
• Epworth Sleepiness Scale (ESS) score—expect ≥10 in symptomatic patients 4, 3
• Sleep diary documenting sleep-wake patterns over 1-2 weeks 5
• Bed partner observations if available 6, 4

Screen for comorbid conditions that commonly coexist with SWD:

• Obstructive sleep apnea (affects 24% of adults and causes similar symptoms) 6, 7
• Restless legs syndrome 5
• Depression and anxiety disorders 5
• Medication review for sedating agents 6, 4

Order baseline laboratory tests to exclude secondary causes:

• Thyroid stimulating hormone (TSH) for hypothyroidism 4
• Complete blood count 4
• Liver function tests 4
• Serum chemistry 4

Treatment Algorithm

Step 1: Non-Pharmacologic Interventions (First-Line)

Implement sleep/circadian hygiene measures:

• Maintain a consistent sleep-wake schedule even on days off 4
• Schedule two brief 15-20 minute naps during or before shifts 4, 8
• Use bright light therapy during night shifts to partially re-entrain the circadian clock 8, 2
• Avoid bright light exposure during the commute home and use blackout curtains 2
• Avoid heavy meals and alcohol before sleep periods 4
• Increase daytime bright light exposure on days off 7

Consider melatonin for sleep promotion:

• Administer melatonin to help achieve sleep during required rest periods 8, 2
• Timing should be individualized based on desired sleep period 2

Use strategic caffeine:

• Consume caffeinated beverages before shifts and during scheduled breaks 8
• Avoid caffeine 4-6 hours before planned sleep 8

Step 2: Pharmacologic Treatment (When Non-Pharmacologic Measures Are Insufficient)

Modafinil is the FDA-approved first-line pharmacologic treatment for excessive sleepiness in SWD:

• Dosing: 200 mg taken approximately 1 hour before the start of the night shift 3, 1
• This dose produces statistically significant improvement in wakefulness as measured by sleep latency tests and Clinical Global Impression of Change 3
• Modafinil improves sustained attention, memory, and overall clinical condition 9
• Armodafinil is an alternative FDA-approved option with similar efficacy 1, 8

Important safety considerations:

• Advise patients not to alter behavior regarding potentially dangerous activities until response to medication is established 3
• Monitor for allergic reactions—instruct patients to stop medication immediately if rash, hives, or mouth sores develop 3

Step 3: Optimize Underlying Conditions

Address any identified medical, neurological, or psychiatric disorders before or concurrent with SWD treatment:

• If obstructive sleep apnea is identified, initiate CPAP therapy before considering other diagnoses 7
• Optimize management of cardiovascular, metabolic, or endocrine conditions 7
• Carefully withdraw sedating medications if possible 4

Critical Pitfalls to Avoid

Do not use benzodiazepines for sleep promotion in this population:

• Risk of decreased cognitive performance, dependence, and next-morning impairment 7
• Exercise caution with zolpidem due to risk of next-morning impairment 7

Do not assume all shift workers have SWD:

• Only 30% of shift workers develop clinically significant SWD 2
• Diagnosis requires meeting specific criteria including temporal relationship to work schedule and exclusion of other disorders 3

Do not overlook workplace safety implications:

• SWD increases risk of work-related injuries and motor vehicle accidents 6, 9
• Drowsy driving causes 15-33% of fatal crashes 6
• Address fitness for duty, particularly in safety-sensitive occupations 6

Long-Term Considerations

The most definitive treatment is switching to daytime work, though this may not be feasible for all workers 2

SWD is associated with increased risk of:

• Cardiovascular disease 9
• Gastrointestinal disease 9
• Obesity and insulin resistance 6
• Cancer 6
• Decreased quality of life and productivity 1, 9