Symptom differences in moderate to severe IBS patients based on predominant bowel habit

We sought to determine if irritable bowel syndrome (IBS) patients with different bowel habit predominance differ in self-reported viscerosensory symptoms related to the upper and lower gastrointestinal (GI) tract, somatosensory symptoms, and constitutional functions.

Six hundred and twenty-five Rome criteria-positive IBS patients completed a bowel symptom questionnaire (BSQ), psychological symptom checklist (SCL-90), and health status (SF-36). Bowel habit predominance for IBS patients was determined using the Rome criteria for functional constipation (IBS-C; n = 140) and functional diarrhea (IBS-D; n = 216). The BSQ included questions about viscerosensory symptoms of the upper (chest pressure, bloating, fullness, early satiety, nausea) and lower GI tract (bloating, pain, incomplete evacuation), somatosensory symptoms related to the musculoskeletal system (pain in neck/shoulders, lower back/hip, muscles/joints), and constitutional functions (sleep, appetite, libido). Analysis was further conducted between the IBS-C and IBS-D patients, controlling for gender and quality of sleep, and using the Bonferroni correction to control for multiple comparisons.

Female gender was more prevalent among IBS-C than IBS-D (77% vs 56.1%, p < 0.01), whereas age did not differ (40.2 +/- 1.2 yr vs 39.5 +/- 1.0 yr). Symptoms referred to the upper GI were more prevalent in IBS-C than IBS-D: early satiety (56.7% vs 33.9%, p < 0.004), fullness (63.2% vs 38.5%, p < 0.05), and a trend for upper bloating (80.3 vs 62.6%). IBS-C patients reported higher severity ratings for lower GI bloating (p < 0.001). IBS-C more commonly reported musculoskeletal symptoms (92.2% vs 75.4%, p < 0.001), as well as impairment in sleep (31.3 vs 17.5%, p < 0.009), appetite (35.0% vs 18.4%, p < 0.015) and sexual function (45.2% vs 33.1%, p < 0.0021). There were no differences in SCL-90 and SF-36 scores.

Compared with the IBS-D group, the IBS-C patients show greater prevalence of a wide range of symptoms referred to the upper and lower abdomen, musculoskeletal, and constitutional functions. These findings may be related to differences in autonomic or perceptual responses to visceral and somatic stimuli, and are likely to have implications for treatment responses in the two subgroups.