Sex, gender, and irritable bowel syndrome: making the connections

Irritable bowel syndrome (IBS) is a widespread chronic health condition experienced more often by women than by men. The extent to which women outnumber men varies, however, with a narrower sex ratio found in population surveys and the widest in gastroenterology clinics. This suggests that explanations of women's excess risk of this condition likely involve both sex, or biological, differences between men and women as well as gender, or social, differences.

This article reviews research on sex and gender factors in IBS and, in particular, the ways in which these factors affect the risk of IBS, either independently or in synergy.

A multidisciplinary literature review of English-language IBS research published between 1966 and 2002 was conducted using a number of electronic databases (ASSIA, MEDLINE, PsycLIT, and SSCI/Web of Knowledge), augmented by manual search of issues not yet entered onto the databases. The key terms sex, gender, women, men, and irritable bowel disease were used to identify articles with potential relevance; titles and abstracts were reviewed and downloaded to a bibliographic referencing system. This approach yielded approximately 450 articles of interest in the subject area.

The literature review highlighted a range of sex- and gender-linked factors in IBS, including hormonal factors, genetic differences, psychosocial factors related to stress, mental well-being, gender roles, and the experience of sexual abuse. In addition, the literature suggests that gender-related factors overlap each other in explanations of IBS among women, and the interactions between these factors and sex-linked biology are not yet fully understood.

A complex model is needed-reflecting sex- and gender-linked factors and their interactions-to fully understand how these factors affect variations in risk and outcome between men and women with IBS.