|
Sign In to gain access to subscriptions and/or personal tools.
|
Comparisons of the Variability of Three Markers of the Human Circadian Pacemaker
Elizabeth B. Klerman
Division of Sleep Medicine, Brigham & Women's Hospital and Harvard Medical School, Boston, MA, USA; Division of Sleep Medicine, Brigham and Women's Hospital, 221 Long-wood Avenue, Boston, MA 02115, USA ebklerman{at}hms.harvard.edu
Hayley B. Gershengorn
Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
Jeanne F. Duffy
Division of Sleep Medicine, Brigham & Women's Hospital and Harvard Medical School, Boston, MA, USA
Richard E. Kronauer
Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
A circadian pacemaker within the central nervous system regulates the approximately 24-h physiologic rhythms in sleep cycles, hormone secretion, and other physiologic functions. Because the pacemaker cannot be examined directly in humans, markers of pacemaker function must be used to study the pacemaker and its response to environmental stimuli. Core body temperature (CBT), plasma cortisol, and plasma melatonin are three marker variables frequently used to estimate the phase of the human pacemaker. Measurements of circadian phase using markers can contain variability due to the circadian pacemaker itself, the intrinsic variability of the marker relative to the pacemaker, the method of analysis of the marker, and the marker assay. For this report, we compared the mathematical variability of a number of methods of identifying circadian phase from CBT, plasma cortisol, and plasma melatonin data collected in a protocol in which pacemaker variability was minimized using low light levels and regular timing of both the light pattern and the rest/activity schedule. We hoped to assess the relative variabilities of the different physiological markers and the analysis methods. Methods were based on the crossing of an absolute threshold, on the crossing of a relative threshold, or on fitting a curve to all data points. All methods of calculating circadian phase from plasma melatonin data were less variable than those calculated using CBT or cortisol data. The standard deviation for the phase estimates using CBT data was 0.78 h, using cortisol data was 0.65 h, and for the eight analysis methods using melatonin data was 0.23 to 0.35 h. While the variability for these markers might be different for other subject populations and/or less stringent study conditions, assessment of the intrinsic variability of the different calculations of circadian phase can be applied to allow inference of the statistical significance of phase and phase shift calculations, as well as estimation of sample size or statistical power for the number of subjects within an experimental protocol.
Key Words: circadian rhythms • cortisol • temperature • melatonin • mathematical analysis • circadian phase
Journal of Biological Rhythms, Vol. 17, No. 2,
181-193 (2002)
DOI: 10.1177/074873002129002474
 CiteULike  Complore  Connotea  Del.icio.us  Digg  Reddit  Technorati  Twitter What's this?
This article has been cited by other articles:
|
|
|
|
 
G. Vandewalle, S. N. Archer, C. Wuillaume, E. Balteau, C. Degueldre, A. Luxen, P. Maquet, and D.-J. Dijk
Functional Magnetic Resonance Imaging-Assessed Brain Responses during an Executive Task Depend on Interaction of Sleep Homeostasis, Circadian Phase, and PER3 Genotype
J. Neurosci.,
June 24, 2009;
29(25):
7948 - 7956.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. A. Rahman, A. Kollara, T. J. Brown, and R. F. Casper
Selectively Filtering Short Wavelengths Attenuates the Disruptive Effects of Nocturnal Light on Endocrine and Molecular Circadian Phase Markers in Rats
Endocrinology,
December 1, 2008;
149(12):
6125 - 6135.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. J. Burgess, V. L. Revell, and C. I. Eastman
A three pulse phase response curve to three milligrams of melatonin in humans
J. Physiol.,
January 15, 2008;
586(2):
639 - 647.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
B. L. Parry, C. J. Meliska, D. L. Sorenson, A. M. Lopez, L. F. Martinez, S. Nowakowski, R. L. Hauger, and J. A. Elliott
Increased Melatonin and Delayed Offset in Menopausal Depression: Role of Years Past Menopause, Follicle-Stimulating Hormone, Sleep End Time, and Body Mass Index
J. Clin. Endocrinol. Metab.,
January 1, 2008;
93(1):
54 - 60.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. W. Cain, D. W. Rimmer, J. F. Duffy, and C. A. Czeisler
Exercise Distributed across Day and Night Does Not Alter Circadian Period in Humans
J Biol Rhythms,
December 1, 2007;
22(6):
534 - 541.
[Abstract]
[PDF]
|
|
|
|
|
|
|
M. Dubik
Melatonin, Sleep, and ADHD
AAP Grand Rounds,
May 1, 2007;
17(5):
58 - 59.
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. J. Lewy
Melatonin and Human Chronobiology
Cold Spring Harb Symp Quant Biol,
January 1, 2007;
72(0):
623 - 636.
[Abstract]
[PDF]
|
|
|
|
|
|
|
N. Goel
An arousing, musically enhanced bird song stimulus mediates circadian rhythm phase advances in dim light
Am J Physiol Regulatory Integrative Comp Physiol,
September 1, 2006;
291(3):
R822 - R827.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Liu and J. Borjigin
Free-Running Rhythms of Pineal Circadian Output
J Biol Rhythms,
October 1, 2005;
20(5):
430 - 440.
[Abstract]
[PDF]
|
|
|
|
|
|
|
T. Liu and J. Borjigin
Reentrainment of the Circadian Pacemaker through Three Distinct Stages
J Biol Rhythms,
October 1, 2005;
20(5):
441 - 450.
[Abstract]
[PDF]
|
|
|
|
|
|
|
J. M. Zeitzer, S. B. S. Khalsa, D. B. Boivin, J. F. Duffy, T. L. Shanahan, R. E. Kronauer, and C. A. Czeisler
Temporal dynamics of late-night photic stimulation of the human circadian timing system
Am J Physiol Regulatory Integrative Comp Physiol,
September 1, 2005;
289(3):
R839 - R844.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Arendt
Melatonin: Characteristics, Concerns, and Prospects
J Biol Rhythms,
August 1, 2005;
20(4):
291 - 303.
[Abstract]
[PDF]
|
|
|
|
|
|
|
H. J. Burgess and C. I. Eastman
Short Nights Attenuate Light-Induced Circadian Phase Advances in Humans
J. Clin. Endocrinol. Metab.,
August 1, 2005;
90(8):
4437 - 4440.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
N. Goel
Late-night presentation of an auditory stimulus phase delays human circadian rhythms
Am J Physiol Regulatory Integrative Comp Physiol,
July 1, 2005;
289(1):
R209 - R216.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Benloucif, M. J. Guico, K. J. Reid, L. F. Wolfe, M. L'Hermite-Baleriaux, and P. C. Zee
Stability of Melatonin and Temperature as Circadian Phase Markers and Their Relation to Sleep Times in Humans
J Biol Rhythms,
April 1, 2005;
20(2):
178 - 188.
[Abstract]
[PDF]
|
|
|
|
|
|
|
M. Ruger, M. C. M. Gordijn, D. G. M. Beersma, B. de Vries, and S. Daan
Nasal versus Temporal Illumination of the Human Retina: Effects on Core Body Temperature, Melatonin, and Circadian Phase
J Biol Rhythms,
February 1, 2005;
20(1):
60 - 70.
[Abstract]
[PDF]
|
|
|
|
|
|
|
C. Gronfier, K. P. Wright Jr., R. E. Kronauer, M. E. Jewett, and C. A. Czeisler
Efficacy of a single sequence of intermittent bright light pulses for delaying circadian phase in humans
Am J Physiol Endocrinol Metab,
July 1, 2004;
287(1):
E174 - E181.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. F. Hatfield, J. Herbert, E. J. W. van Someren, J. R. Hodges, and M. H. Hastings
Disrupted daily activity/rest cycles in relation to daily cortisol rhythms of home-dwelling patients with early Alzheimer's dementia
Brain,
May 1, 2004;
127(5):
1061 - 1074.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
E. K. Baehr, C. I. Eastman, W. Revelle, S. H. L. Olson, L. F. Wolfe, and P. C. Zee
Circadian phase-shifting effects of nocturnal exercise in older compared with young adults
Am J Physiol Regulatory Integrative Comp Physiol,
June 1, 2003;
284(6):
R1542 - R1550.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
