Free-running (non-entrained to 24-h period) circadian sleep disorder in a patient with obstructive sleep apnea, delayed sleep phase tendency, and lack of social interaction

Diagnostic and Treatment Challenges of Sighted Non–24-Hour Sleep-Wake Disorder

“…43 Bright light monotherapy successfully entrained one case with sighted N24SWD. 44 In two case reports, bright light upon awakening combined with melatonin 2 mg, 2 to 3 hours before planned bedtime 45 or 3 mg, 1 hour before planned bedtime 46 successfully entrained the sleep-wake rhythm but with a delayed sleep phase. In another case report, morning bright light therapy at 10,000 lux for 30 minutes and evening melatonin 0.5 to 0.75 mg appeared to stabilize sleep offset but not sleep onset, and melatonin rhythms did not entrain.…”

“…Of the subjects who entrained to a 24-hour schedule, most remained slightly delayed with respect to the environment, a finding noted in previous reports of successful entrainment in N24SWD. 23,45,46 The delayed timing of entrainment may be due to the timing of melatonin close to bedtime. The time of entrainment depends on achieving an adequate phase advance, which depends on timing of melatonin dosing relative to the person's PRC.…”

“…In two prior case reports, only one patient was able to maintain longterm entrainment. 45,46 The limited adherence with our approach may also be due to the timing of melatonin. Based on the PRC in healthy adults, timing melatonin approximately 7 hours before sleep onset would result in the maximum phase advance, 11 and timing it 2 to 3 hours before bedtime, or close to DLMO, results in little to no effect.…”

Circadian disruption and human health: A bidirectional relationship

“…Recent studies have demonstrated a lack of entrainment in 39% and abnormal entrainment in 24% of individuals with no light perception (Flynn‐Evans, Tabandeh, Skene, & Lockley, ). While more rare, this disorder can also occur in sighted individuals, and is thought to be due to multiple factors, including a prolonged intrinsic circadian period (Kitamura et al., ), decreased responsiveness to environmental entraining signals, and decreased social cues (Brown, Quan, & Eichling, ; Kuzniar, Kovacevic‐Ristanovic, Nierodzik, & Smith, ).…”

An unusual circadian rhythm in an active duty service member

“…Based on these findings, treatment for a circadian rhythm disorder was initiated with a regular nightly sleep prescription of midnight-0730 starting on day 14, bright light exposure upon awakening (going out into the direct sunlight for 10 min upon awakening) and 1 mg of melatonin 30 min prior to sleep [3,4]. The patient reported some initial difficulties maintaining a regular sleep-wake cycle.…”