Postinfectious functional gastrointestinal disorders: a focus on epidemiology and research agendas

Epidemiologic research is fundamental and complementary to our understanding of disease and development of primary, secondary, and tertiary interventions. To put the current evidence into context and identify gaps and research priorities in the areas of disease attribution, burden of disease, clinical characterization, and management of postinfectious functional gastrointestinal disorders (PI-FGDs), we took a multidisciplinary approach from the domains of infectious disease, gastroenterology, epidemiology, and public health. Our review of data from these disciplines found that, despite a complete understanding of pathoetiology, studies continue to accumulate and point toward evidence of a causal association for FGD. For some FGDs, Bradford Hill's criteria for causality yield more certainty than other criteria. In addition, the growing recognition of the impact of acute foodborne illness on economics and society is leading to exploration of the potential long-term health effects and disease burden of PI-FGDs, although a paucity of data exist in terms of pathogen-specific risk, disability duration, and relevant disability weights. Lastly, the understanding of PI-FGDs is changing the way research is approached and suggests a need for a more expansive exploration of biologic mechanisms and how FGDs are categorized. Areas of research priorities are catalogued in this paper and will hopefully provide inspiration for future studies and contributions to the field of gastroenterology.