Stability of Melatonin and Temperature as Circadian Phase Markers and Their Relation to Sleep Times in Humans

Journal of Biological Rhythms - Tập 20 Số 2 - Trang 178-188 - 2005
Susan Benloucif1, M. J. Guico2, Kathryn J. Reid3, Lisa F. Wolfe4, M L’Hermite-Baleriaux5, Phyllis C. Zee6
1Center for Sleep and Circadian Biology, Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA.
2Departments of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
3Center for Sleep and Circadian Biology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
4Departments of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
5Faculté de médecine, Université Libre de Bruxelles, Brussels, Belgium
6Center for Sleep and Circadian Biology, Departments of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois

Tóm tắt

Circadian rhythms of core body temperature and melatonin are commonly used as phase markers of the circadian clock. Melatonin is a more stable marker of circadian phase when measured under constant routine conditions. However, little is known about the variability of these phase markers under less controlled conditions. Moreover, there is little consensus about the preferred method of analysis. The objective of this study was to assess various methods of calculating melatonin and temperature phase in subjects with regular sleep schedules living in their natural environment. Baseline data were analyzed from 42 healthy young subjects who were studied on at least two occasions. Each hospital admission was separated by at least 3 weeks. Subjects were instructedto maintain a regular sleep schedule, which was monitored for 1 week before admission by sleep logs and actigraphy. Subjects spent one habituation night under controlled conditions prior to collecting baseline temperature and melatonin measurements. The phase of the melatonin rhythm was assessed by 9 different methods. The temperature nadir (Tmin) was estimated using both Cleveland and Cosine curve fitting procedures, with and without demasking. Variability between admissions was assessed by correlation analysis and by the mean absolute difference in timing of the phase estimates. The relationship to sleep times was assessed by correlation of sleep onset or sleep offset with the various phase markers. Melatonin phase markers were more stable and more highly correlated with the timing of sleep than estimates of Tmin. Of the methods for estimating Tmin, simple cosine analysis was the least variable. In addition, sleep offset was more strongly correlated with the various phase markers than sleep onset. The relative measures of melatonin offset had the highest correlation coefficients, the lowest study-to-study variability, and were more strongly associated with sleep timing than melatonin onsets. Concordance of the methods of analysis suggests a tendency for the declining phase of the melatonin profile to be more stable and reliable than either markers of melatonin onset or measures of the termination of melatonin synthesis.

Từ khóa


Tài liệu tham khảo

10.1046/j.1365-2869.2000.00196.x

Baker S, 2000, Principles and Practice of Sleep Medicine, 606

10.1177/074873049200700301

Burgess HJ, 2003, Sleep, 26, A95

10.1016/j.neulet.2003.11.032

10.1207/S15402010BSM0102_3

10.1053/smrv.2001.0215

10.1177/074873049701200308

10.1080/01621459.1979.10481038

10.1126/science.3726555

10.3109/07420529209064548

10.1111/j.1365-2265.1994.tb03940.x

Duffy JF, 1999, J Investig Med, 47, 141

10.1152/ajpendo.00268.2001

10.3109/07420528909059141

10.1007/0-306-46814-X_27

10.1016/0361-9230(83)90033-3

10.1177/074873002129002474

10.1177/074873099129000678

10.1177/074873099129000641

10.3109/07420528909059144

10.1126/science.7434030

Martin SK, 1998, Sleep, 21, 154

10.1081/CBI-120006080

10.1111/j.1600-079X.1989.tb00412.x

10.3109/07420528409063897

10.3109/07420528909059140

10.1016/0166-4328(96)00083-6

10.1210/jcem-73-2-225

10.1093/sleep/15.5.434

10.1016/S0304-3940(97)13460-7

10.1210/jcem-73-2-227

10.1001/archpsyc.58.1.69

Van Cauter E, 1994, Am J Physiol, 266, E953

10.1111/j.1600-079X.1996.tb00232.x

10.1177/074873049701200507

10.1111/j.1469-7793.2001.t01-1-00937.x

10.1007/BF02004495

10.1034/j.1600-079x.2002.10808.x

10.1111/j.1469-7793.2000.00695.x