Associations between sociodemographic, sampling and health factors and various salivary cortisol indicators in a large sample without psychopathology

• Published in: Psychoneuroendocrinology 2009-09, Vol.34 (8), p.1109-1120
• Main Authors: Vreeburg, Sophie A, Kruijtzer, Boudewijn P, van Pelt, Johannes, van Dyck, Richard, DeRijk, Roel H, Hoogendijk, Witte J.G, Smit, Jan H, Zitman, Frans G, Penninx, Brenda W.J.H
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Age Factors; Aged; Behavioral psychophysiology; Biological and medical sciences; Biomarkers - metabolism; Circadian Rhythm; Cortisol awakening response; Dexamethasone - pharmacology; Dexamethasone suppression test; Diurnal slope; Endocrinology & Metabolism; Female; Fundamental and applied biological sciences. Psychology; Health Status; Hormones and behavior; HPA-axis; Humans; Hydrocortisone - metabolism; Male; Middle Aged; Psychiatry; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Research Design; Saliva - drug effects; Saliva - metabolism; Salivary cortisol; Sex Factors; Socioeconomic Factors; Time Factors; Wakefulness
• ISSN: 0306-4530; 1873-3360
• DOI: 10.1016/j.psyneuen.2009.04.024

Summary Background Cortisol levels are increasingly often assessed in large-scale psychosomatic research. Although determinants of different salivary cortisol indicators have been described, they have not yet been systematically studied within the same study with a large sample size. Sociodemographic, health and sampling-related determinants of salivary cortisol levels were examined in a sample without potential disturbances because of psychopathology. Methods Using 491 respondents (mean age = 43.0 years, 59.5% female) without lifetime psychiatric disorders from the Netherlands Study of Depression and Anxiety (NESDA), sociodemographic, sampling and health determinants of salivary cortisol levels were examined. Respondents collected seven salivary cortisol samples providing information about 1-h awakening cortisol, diurnal slope, evening cortisol and a dexamethasone (0.5 mg) suppression test (DST). Results Higher overall morning cortisol values were found for smokers, physically active persons, persons without cardiovascular disease, sampling on a working day or in a month with less daylight. In addition, the cortisol awakening response was significantly flattened for males, persons with cardiovascular disease, those with late awakening times and those with longer sleep duration. Diurnal slope was steeper in men, physically active persons, late awakeners, working persons, and season with less daylight. A higher evening cortisol level was associated with older age, smoking and season with more daylight. Cortisol suppression after dexamethasone ingestion was found to be less pronounced in smokers, less active persons and sampling on a weekday. Conclusion Sociodemographic variables (sex, age), sampling factors (awakening time, working day, sampling month, sleep duration) and health indicators (smoking, physical activity, cardiovascular disease) were shown to influence different features of salivary cortisol levels. Smoking had the most consistent effect on all cortisol variables. These factors should be considered in psychoneuroendocrinology research.