Circadian Rhythm Sleep Disorders | A Brief Review Time Zone Change

Time Zone Change (Jet-Lag):

• Occurs after rapid travel across multiple time zones.
• Often good sleep alternates with poor sleep on subsequent nights.
• East-bound travel:  Phase adjustment = 60 minutes/day
• West-bound travel: Phase adjustment = 90 minutes/day
• Other physiologic functions:  Hormonal release, GI function, appetite may take more than a week to regulate with the new time zone.
• Patients with manic-depressive illness may experience an exacerbation of mania (eastward flights more common than westward flights).
• PSG:  Variable, fragmented sleep, most disrupted in second half of sleep period.
• Persistence of symptoms beyond 2 weeks suggests another disorder.