Source: Eur J Gastroenterol Hepatol  |  Posted 9 years ago

Approximately one-quarter of patients with irritable bowel syndrome (IBS) demonstrate alternating rather than diarrhoea- or constipation-predominant bowel habits, say Spanish and Australian researchers.

They suggest these patients belong in a separate IBS alternating sub-type (A-IBS), by Rome II criteria, rather than in either diarrhoea-predominant (D-IBS) or constipation predominant (C-IBS) IBS subtypes.

The majority of A-IBS patients, however, consider themselves to be constipated, explain investigators, led by Dr. Fermin Mearin of Centro Medico Teknon in Barcelona. They say this is because clinical manifestations in A-IBS are more akin to C-IBS subtype than the D-IBS subtype.

The researchers also report abdominal discomfort/pain and frequency of doctor visits are greater in the A-IBS subtype than in the other two subtypes. Health-related quality of life (HRQOL) is impaired similarly in all three subtypes.

Two thousand people were randomly selected to represent the general population, with 281 classified as potential IBS subjects and 1,719 classified as non-potential IBS patients. Rome II IBS supportive symptoms were used to determine bowel habit classifications.

Of 201 people meeting Rome I criteria, 15% presented with D-IBS, 44% with C-IBS, 19% with A-IBS and the other 22% had normal bowel habits. Of 63 people meeting Rome II criteria, 23% presented with A-IBS.

Under participant self-assessment, 16% of those meeting Rome I criteria considered themselves to have D-IBS, 66% to have C-IBS and 18% to have A-IBS while 24% of those meeting Rome II criteria considered themselves to have A-IBS. Most people classified as A-IBS using Rome II criteria considered themselves to be constipated.

A-IBS clinical manifestations were similar to those of C-IBS, the investigators note, with the addition of defecatory urgency.