This study reinforces the recent finding from United States, indicating an increase in the incidence of FBI over the last 15 years. More importantly, the increased incidence of FBI was associated with changes in the etiology as well as demographics of the affected patients, characterized by an increase in the diagnosis of EoE, a reduction in peptic-related stricture, and a reduction in age of presentation. Given that EoE is becoming one of the most common causes for FBI, the diagnosis should be considered in all patients where there is no other clear cause and, if in doubt, esophageal mucosal biopsy should be taken. Our study also confirms that endoscopic removal of impacted bolus is highly effective and safe, with no major morbidity or related death.
The increasing number of cases of EoE presenting for the first time with FBI over the last decade are in keeping with the data from recent epidemiological studies.[4,10–13] A populational cohort study in Switzerland suggested a 153% increased prevalence of EoE cases over the last decade. However, this was associated with a 63% increase in the number of endoscopies and biopsies in the last decade,[4,12,13] indicating that increased awareness of EoE by the treating physician may be a contributor to the increased prevalence. Although a large recent study that examined the esophageal biopsy findings for patients who presented with dysphagia found an increasing prevalence of EoE from 0.1% in 2002 to 1.9% in 2005, the major weakness of this study is that only a small proportion of these patients had esophageal biopsies. Other studies conducted among unselected patients presenting to endoscopy reported prevalence rates varied between 0.9% and 6.5%,[15–18] which may in part related to the variability in the diagnostic criteria (i.e. 15 vs 20 eosinophils/hpf diagnostic cut off) and the location of esophageal biopsies.[19,20] Thus, it remains unclear whether the increasing prevalence in EoE in the current study is related to an increasing awareness or a true increased incidence of EoE. This issue can only be clarified by prospective data collection on all cases of FBI, in which esophageal mucosal biopsy should be performed in all cases given that endoscopic diagnosis can be unreliable. Available data, however, appear to suggest an increase in the estimated annual incidence of EoE from 4.4 to 7.4 per 100 000 inhabitants, which is comparable with that from United States (between 1976 and 2005)[12,13] and Australia.[5,9,21] The current study is consistent with the recent estimated rising incidence of EoE in Australia, from 0.35 per 100 000 person-years during 1991–1995 to 9.45 per 100 000 person-years during 2001–2005.
This study is, however, the first to demonstrate a link between the increasing prevalence of FBI and the changes in the etiology of FBI.[4,10–13] Overall, there is an increased prevalence of EoE but a reduction in peptic-related causes. Although the effects of increased awareness, and thus esophageal biopsy practice, cannot be excluded, the changes in the age presentation strongly support a real change in the etiology of the condition. Given that EoE is a disease of a younger population, the increase in the incidence of EoE is likely to be the principal reason for the reduction in the age of presentation in our cohort. Conversely, the decrease in peptic-related strictures as the cause of FBI, which is most common in the elderly, would also contribute to the reduction in the age of presentation. These changes in epidemiology of FBI at the RAH are unlikely to be related to "referral bias" because there has been no significant change in the referral pattern from the emergency department to other units within our hospital. The reduction in the incidence of peptic strictures and Schatzki's rings over time may relate to the more common use and highly effective treatment of reflux disease with proton pump inhibitors. This has been shown in many studies, especially in symptomatic patients.[22,23,24]
Potentially, changes in the management of food bolus over time may also have contributed to the changes in prevalence of FBI in our cohort. Previously, conservative management in the Emergency Department with agents such as glucagon, buscopan benzodiazepines, or fizzy drinks may have been used more commonly. Currently, as most recent data suggest that these conservative approaches are no more beneficial than placebo, these therapies are less commonly used and endoscopic removal has become the therapeutic modality of choice. This change in practice may have contributed to the increase in the number of cases with FBI admitted under our Unit.
The authors acknowledge inherent weaknesses of the retrospective nature of the current study. However, the relevant data have been collected prospectively and maintained over the study period. Although detailed analysis of patients who were admitted under ENT Unit was not performed, it is unlikely to influence our overall results as the pattern and number of referrals to this Unit has not changed over the 15 years and contributed only 40% to the overall cohort (Fig. 1). The increase in referrals to Gastroenterology may relate to both the increasing population of South Australia (from 1.0 to 1.5 million over the studied period) and the potential change in referral pattern as gastroenterological approach for bolus disimpaction is highly efficacious.
In conclusion, there has been an increase in the prevalence of FBI over 15 years at our hospital, which was associated with a change in the etiology and demographics. The age of presentation is becoming younger with an increased prevalence of EoE and a reduction in peptic strictures. While this may indicate an increased incidence of EoE, heightened awareness of the diagnosis with a lower threshold for esophageal biopsy is also a potential contributor. Overall, our findings suggest that EoE should be thought of in all cases of FBI and biopsy should be performed in all cases that have no apparent abnormality on upper endoscopy.
J Gastroenterol Hepatol. 2013;28(6):963-966. © 2013 Blackwell Publishing