Long-term stability of diurnal salivary cortisol and alpha-amylase secretion patterns.
This study aimed to investigate long-term stability and variability of diurnal cortisol and alpha-amylase patterns. Diurnal cortisol and alpha-amylase secretion patterns were assessed on a single workday with three waves of measurement across a total time period of 24months in 189 participants. Separate hierarchical linear models were analyzed, with and without a number of potential predictor variables (age, BMI, smoking, chronic stress, stress reactivity). While low long-term stability was found in diurnal cortisol, the stability of diurnal alpha-amylase was moderate across the time period of 24months. Several predictor variables had a positive impact on diurnal cortisol and alpha-amylase secretion patterns averaged across waves. Our findings underpin the notion that long-term stability is not necessarily warranted in longitudinal studies. It is important to choose an appropriate study design when attempting to disentangle clinically and biologically relevant changes from naturally occurring variations in diurnal cortisol and alpha-amylase.
University of Marburg, Dept. of Psychology, Germany.
Nadine
N
Skoluda
University of Zurich, Dept. of Psychology, Switzerland.
Roberto
R
La Marca
University of Marburg, Dept. of Psychology, Germany.
Mario
M
Gollwitzer
Institute of Occupational and Social Medicine, University of Dusseldorf, Germany.
Andreas
A
Müller
Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Germany.
Heribert
H
Limm
Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Ludwig-Maximilians-University Munich, Munich, Germany; Department of Psychosomatic Medicine and Psychotherapy, Klinikum rechts der Isar, Technische Universitaet Muenchen, Munich, Germany.
Birgitt
B
Marten-Mittag
Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Germany.
Harald
H
Gündel
Institute of Occupational and Social Medicine, University of Dusseldorf, Germany.
Peter
P
Angerer
University of Marburg, Dept. of Psychology, Germany. Electronic address: nater@uni-marburg.de.
Urs M
UM
Nater
D000328:Adult; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012463:Saliva / Q000378:metabolism*; D055815:Young Adult; D000516:alpha-Amylases / Q000378:metabolism*
D000516:alpha-Amylases; D006854:Hydrocortisone
Alpha-amylase; Cortisol; Long-term stability; Salivary biomarker