The aims of this study were to estimate the prevalence of chronic constipation and to evaluate the diagnostic accuracy of the symptoms and the self-reported definition of constipation. A cross-sectional survey was conducted in the general community in 1999. A questionnaire comprising 21 items was developed and mailed to a random sample of 489 subjects who were aged between 18 and 65 years and who belonged to a Spanish population. In the 349 subjects (71%) responding to the questionnaire, the prevalence of self-reported constipation was 29.5% (95% confidence interval (CI): 24.9, 34.3) versus 19.2% (95% CI: 15.1, 23.3) and 14.0% (95% CI: 10.4, 17.7) based on Rome I and Rome II criteria, respectively. Agreement was good between self-reported and Rome I criteria (kappa: 0.68) and between Rome I and Rome II criteria (kappa: 0.71), and it was moderate between self-reported and Rome II criteria (kappa: 0.55). Female gender was identified to be a risk factor for constipation; fiber intake and physical exercise were found to be protective factors. Likelihood ratios were higher for the presence of anal blockage and straining and for the absence of hard stools. Chronic constipation is a highly prevalent problem, especially in women. Different prevalence estimates of constipation were observed using different criteria, although agreement between them was acceptable. Anal blockage, straining, and hard stools show the greatest accuracy for the diagnosis of constipation.

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder in western countries. Previous studies on IBS, mostly based on faecal samples, suggest alterations in the intestinal microbiota. However, no consensus has been reached regarding the association between specific bacteria and IBS. We explore the alterations of intestinal bacterial communities in IBS using massive sequencing of amplified 16S rRNA genes. Mucosal biopsies of the ascending and descending colon and faeces from 16 IBS patients and 9 healthy controls were analysed. Strong inter-individual variation was observed in the composition of the bacterial communities in both patients and controls. These communities showed less diversity in IBS cases. There were larger differences in the microbiota composition between biopsies and faeces than between patients and controls. We found a few over-represented and under-represented taxa in IBS cases with respect to controls. The detected alterations varied by site, with no changes being consistent across sample types.

The Cuestionario de Calidad de Vida de Incontinencia Anal incorporates sufficient requirements of reliability and validity to be applied to patients with fecal incontinence.

The frequency of constipation and diarrhoea remains relatively stable over time. Changes in IBS subtypes are common, but changes between constipation and diarrhoea are rare. Alternating IBS is more frequent in women.