Sleep-wake Patterns,Circadian Characteristics Of Spontaneous Physical Activity And Deep Body Temperature In Narcolepsy

Part Ⅰ.Sleep-wake patterns,non-rapid eye movements and rapid eye movements sleep cycle in narcolepsyAims: To assess the sleep-wake patterns and rapid eye movement(REM)and non-REM(NREM)sleep cycle in teenagers afflicted with narcolepsy.Methods: It’s a case-control study.Fourteen Chinese narcoleptic patients(9 males;average age: 13.4 ± 2.6 yeras)and 14 healthy age-and sex-matched control subjects(9 males;average age: 13.6 ± 1.8 yeras)were enrolled.Ambulatory 24h polysomnography was recorded for 2 days,with adaptation on day 1 and experimental data collection on day 2,followed by standard multiple sleep latency test(MSLT).Results: The total sleep time over 24h of narcoleptic patients was observed to be 1.5 times that of the control subjects(659.86 ± 162.41 vs.437.52 ± 92.84 min,P < 0.001),characterized by enhanced slow wave sleep(166.54 ± 57.57 vs.100.51 ± 27.56 min,P = 0.001).Frequent sleep-wake transitions were identified in nocturnal sleep with all sleep stages altered to wakefulness(P < 0.001).Despite 8 cases of narcolepsy with sleep onset REM periods at night,the duration of NREM-REM sleep cycle episode(P = 0.563)and the ratio of REM/NREM sleep were not significantly altered(P = 0.132).Conclusion: The 24h total sleep and slow wave sleep of patients were both significantly longer than controls,suggesting that daytime sleepiness in narcolepsy was independent of nocturnal sleep disorders.Sleep fragmentation extended to all sleep stages,indicating impaired sleep-wake cycle and stability of sleep stages.The limited effects on NREM-REM sleep cycle suggest the relative conservation of ultradian regulation of sleep in narcolepsy.Part Ⅱ.Circadian Characteristics of Spontaneous Physical Activity and Deep Body Temperature in NarcolepsyAims: To assess circadian characteristics of spontaneous physical activity and deep body temperature in narcoleptic patients.Methods: It’s a case-control study.Fourteen Chinese narcoleptic patients(9 males;average age: 13.4 ± 2.6 yeras)and 14 healthy age-and sex-matched control subjects(9 males;average age: 13.0 ± 1.4 yeras)were enrolled.All subjects were required to wear the actigraphy(Actiwatch)at home with continuous monitoring of spontaneous physical activity data for 1~2 weeks and complete the daily sleep log.Then all subjects’ deep body temperatures were measured for a whole day.Results: According to actigraphy,the nocturnal activity rate(activity per hour)and daytime activity rate of patients were observed to be 3.17 times(18844.58 ± 8902.63 vs.5940.39 ± 1663.17 /h,P <0.001)and 0.75 times(116864.16 ± 36485.59 vs.155719.93 ± 31165.65 /h,P <0.001)that of the control subjects respectively.The nocturnal/day activity rate ratio in patients was calculated to be 4.5 times that of the controls(0.17 ± 0.08 vs.0.04 ± 0.01,P <0.001).The deep body temperature in both groups showed significant circadian rhythms(P <0.05).The mesor,amplitude and phase peak of deep body temperature were comparable between the two groups(P >0.05).Conclusion: Narcoleptic patients are characterized by impaired circadian rhythm of sleep-wake and spontaneous physical activity.The limited effects on deep body temperature suggest the relative conservation of thermoregulation in narcolepsy.