A team of researchers, from the USA and Germany, investigated behavioral and physiological sleep characteristics in irritable bowel syndrome (IBS) patients, with and without concurrent dyspeptic symptoms.
They assessed 31 women with IBS who were stratified into two groups.
Of these, 15 had bowel symptoms only (IBS-only) and 16 had both lower and upper dyspeptic symptoms (IBS+D). In addition, 23 healthy women served as controls.
The team evaluated subjective sleep quality, insomnia symptoms, alertness, state anxiety, perceived daytime stress, and daytime and nighttime GI symptoms over 4 consecutive days.
|Significant proportion of patients report nighttime GI symptoms.|
|American Journal of Gastroenterology|
On night 4, subjects underwent polysomnographic (PSG) monitoring for an objective assessment of sleep quality including microarousals and respiratory parameters.
In addition, saliva samples were collected for cortisol analyses each morning and evening across the 4 days of the study. Any psychological disturbances were assessed using these samples.
The researchers found that patients reported significantly more dissatisfaction with their sleep quality and increased daytime fatigue, as a result of both insomnia-type symptomatology and non-restful sleep.
These complaints were significantly greater in IBS+D compared to IBS-only for some measures.
Furthermore, a significant proportion of patients, particularly IBS+D patients, reported nighttime GI symptoms.
The team also found that patients reported significantly greater average anxiety across the 4 days. This was greatest in IBS+D group.
Both patient subgroups showed normal levels and circadian changes in cortisol compared to controls. However, the IBS+D group had significantly increased morning salivary cortisol levels than the IBS-only group.
PSG data showed no significant differences between the patient groups and controls.
Whereas, significant correlations were found between psychological distress and retrospective subjective sleep complaints for patients.
Dr Sigrid Elsenbruch's team concluded, "This study confirms the importance of sleep complaints and nighttime GI symptoms in women with IBS that are not substantiated by any objective, physiological evidence.
"Rather, there is a reporting bias regarding sleep disturbances, which appears to be related to symptom severity and psychological disturbances".