Identification of distinct upper and lower gastrointestinal symptom groupings in an urban population

Abstract

Background: The current classification dividing patients with functional gastrointestinal symptoms into subgroups remains controversial.

Aims: To determine whether distinct symptom groupings exist in the community.

Methods: A random sample of Sydney residents in Penrith, Australia was mailed a validated self report questionnaire. Gastrointestinal symptoms including the Rome criteria for irritable bowel syndrome (IBS) and dyspepsia were measured.

Results: Among 730 respondents, the 12 month age and gender adjusted prevalence (adjusted to the Australian population) of IBS, dyspepsia, and gastro-oesophageal reflux were 11.8% (95% confidence interval (CI) 9.3 to 14.3%), 11.5% (95% CI 9.6 to 14.6%), and 17.5% (95% CI 14.2 to 19.9%), respectively. In total, 60% of the population reported four or more gastrointestinal symptoms. There was considerable overlap of IBS with dyspepsia and among the dyspepsia subgroups by application of the Rome criteria. Independently, 10 symptom groupings were identified by factor analysis. The underlying constructs measured by these factors were generally the major abdominal syndromes recognised by the Rome classification: dyspepsia, IBS, reflux, painless constipation, painless diarrhoea, and bloating, in addition to a number of more specific symptom groupings.

Conclusion: Gastrointestinal symptoms are common and overlap in the community, but distinct upper and lower abdominal symptom groupings can be identified.

Figure 1

A comparison of the 10 symptom groupings derived from factor analysis and four a priori defined diagnostic groups based on the questionnaire responses (dyspepsia alone, irritable bowel syndrome alone, both dyspepsia and irritable bowel syndrome, and neither dyspepsia nor irritable bowel syndrome). Note the general similarity of the relevant factors across the diagnostic groups.