Subjective and objective sleep indices in women with irritable bowel syndrome

Patients with irritable bowel syndrome (IBS) commonly report sleep disturbances. This study examined self-report (Pittsburgh Sleep Quality Inventory) sleep quality and polysomnography (PSG) sleep variables in 18 women with mild-to-moderate IBS, 18 with severe IBS and 38 with age- and gender-matched controls. All women were studied on two consecutive nights in a sleep research laboratory where PSG data were collected. Retrospective and daily measures were obtained of self-reported sleep quality, psychological distress and gastrointestinal symptoms across one menstrual cycle. Self-report measures of psychological distress and sleep quality were significantly worse in the IBS-severe (IBS-S) group compared with controls. Rapid eye movement (REM) latency was higher in the two IBS groups on Night 1 than the control group (P = 0.06). Percentage time in REM was highest in the IBS-S on Night 2. All groups demonstrated greater sleep disruption on Night 1 (adaptation) when compared with Night 2. These results highlight the importance of considering the 'first-night effect' in those with IBS and the lack of concordance between self-report and objective indices of sleep in women with IBS.