Actual stress, psychopathology and salivary cortisol levels in the irritable bowel syndrome (IBS)

Although irritable bowel syndrome (IBS) can be considered a biopsychologica l disorder in which an association between life stress and physiological ch anges leading to bowel irregularity is present, there is a lack of data con cerning possible modifications of the adrenal function during the disease. The aim of the present study was to measure biological and psychological va riables related to the activity of the hypothalamo-pituitary-adrenal axis i n IBS patients compared to healthy subjects. Cortisol was measured in the s aliva (obtained by a stress-free, non invasive collection procedure) of 55 IBS outpatients and 28 matched controls. Moreover, each subject completed t he following self-administered questionnaires: the Rome Burnout Inventory ( RBI) in its physical (RBI-PE) and emotional-mental exhaustion (RBI-EME) com ponents, Beck Depression Inventory, State and Trait Anxiety Inventory (STAI ), Perceived Social Support Scale (PSSS) and a Scale for the Assessment of Perceived Actual Work-Non Work Stress. Compared with controls, IBS subjects showed significantly higher levels of cortisol in the morning and lower in the evening, while they maintained the physiological circadian fluctuation (i.e. cortisol morning level higher than in the evening). Moreover, IBS pa tients presented a significant difference from controls in RBI-PE scores, w hich confirms the presence of fatigue, a symptom frequently reported by the patients. Compared with controls, no differences were found in IBS patient s with respect to other psychological parameters, These findings suggest a dysregulation of the adrenal activity in IBS patients. The results may be r elevant considering that changes in cortisol levels have been shown to be s ensitive indicators of psychosocial stress and coping patterns in both labo ratory and life situations.