Research
Effect of day-to-day variations in adrenal cortex hormone levels on abdominal symptoms
1 Faculty of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan
2 National Institute of Occupational Safety and Health, Health Administration and Psychosocial Factor Research Group, 6-21-1 Nagao, Tama-Ku, Kawasaki, Kanagawa 214-8585, Japan
3 Graduate School of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan
4 Advanced Research Center for Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan
BioPsychoSocial Medicine 2010, 4:2 doi:10.1186/1751-0759-4-2
Published: 18 March 2010Abstract
Introduction
The hypothalamic-pituitary-adrenal axis is known to be related to abdominal symptoms, and the relationship between abdominal pain and cortisol secretory patterns has been previously investigated using a cross-sectional approach. Here, we investigated the effect of day-to-day variations in salivary cortisol and dehydroepiandrosterone-sulfate levels on abdominal symptoms in healthy individuals.
Methods
Eleven college students (4 males and 7 females) participated in this study. The participants were asked to collect their saliva immediately after awakening and before bedtime for eight consecutive days. They also completed a questionnaire about abdominal symptoms before bedtime. The linear mixed model was applied to analyze the effects of the day-by-day variability or the 8-day average adrenal hormone level (at awakening, before bedtime, slope from awakening to bedtime) on abdominal symptoms.
Results
The day-to-day variability of cortisol levels before bedtime was negatively related with loose stool, while the day-to-day variability of the cortisol slope was positively correlated with loose stool. A low 8-day average dehydroepiandrosterone-sulfate level at awakening was positively related with frequent bowel movements, loose stool, and long bouts of severe abdominal pain. Likewise, a low 8-day average dehydroepiandrosterone-sulfate slope was positively related with long bouts of abdominal pain.
Conclusions
Low cortisol levels before bedtime and a steeper diurnal cortisol slope during the day may be related to bouts of diarrhea during the day.



