Objective: To explore the natural history of chronic unexplained gastrointestinal (GI) symptoms and to determine the longitudinal trends of prevalence during a 20-year period in a single US community.
Methods: Between January 1, 1990, and December 31, 2009, valid self-report questionnaires of GI symptoms were mailed to randomly selected cohorts of a community. The study used respondents who answered questions on 1 or more of 3 surveys (initial, 1990-1992; second, 2003-2004; and third, 2008-2009). The trends of prevalence of GI symptoms over time were analyzed in responders who completed 3 surveys, and the natural history or transition was evaluated.
Results: The overall prevalence of major symptom groupings including gastroesophageal reflux disease was consistent among residents in a community on 3 survey time points (1990-1992, 2003-2004, and 2008-2009). The transitions of GI symptoms were common in 228 patients who responded to all 3 surveys; only 29% had the same symptom category in 3 surveys; otherwise, symptoms changed over time, resolving, recurring, or transitioning to another disorder. Observed proportions of symptom transitions were significantly different from expected during 20 years (P<.001). Higher non-GI somatic symptom scores were significantly associated with both symptom transitions (odds ratio, 3.9; 95% CI, 1.38 to 10.77) and having sustained symptoms (odds ratio, 12.7; 95% CI, 4.62 to 34.90).
Conclusion: The overall population prevalence of chronic unexplained GI symptoms is stable, but in individuals, transitions seem to be the rule. As these various GI syndromes appear to be so intimately interconnected, the common underlying pathogenesis may account for a major subgroup of chronic unexplained GI disorders.
Functional gastrointestinal disorders (FGIDs) are a heterogeneous group of chronic conditions in which people report recurrent or chronic gastrointestinal (GI) symptoms in the absence of known anatomic or biochemical abnormalities. (1-5) Patients with FGIDs generally report a wide variety of symptoms affecting different regions of the GI tract, and the symptoms often wax and wane over time. (1,6-8) Standardized symptom-based criteria exclusively limited to regions of the GI tract have been developed by the Rome Committee by applying a consensus process. (1,5,6) However, the attribution of a functional GI diagnosis varies according to the criteria applied. For example, 1 in 4 patients diagnosed as having irritable bowel syndrome (IBS) by Rome III criteria fail to meet criteria by Rome IV, and 1 in 4 of these will have no syndromic diagnosis, whereas the rest fall into an alternative disorder for which treatment is not evidence based. (9) The emerging data suggest that a better understanding of the long-term natural history of chronic GI symptoms is needed to accurately classify the disorders. Previous studies have also found that overlap of symptoms between any 2 FGIDs is common in the general population, (10-12) and gastroesophageal reflux disease (GERD) also overlaps more than expected by chance with FGIDs. (10,12,13) Moreover, these various GI symptom complexes frequently transform from one to another over time. (7,8)
Little is known about the long-term natural course of GI symptoms in the community. In a previous study, (8)...