Two recent papers just published in 2018 have documented a dramatic rise in the prevalence of EoE to fect currently more than 1 in 1,000 people

Eosinophilic Esophagitis (EoE) is often classified as a rare disease, with prevalence routinely reported as less than 60 cases per 100,000 in the population. Some research carried out more than one decade ago showed incidence ragint from <1 case per 100,000 inhabitantsin the 1990s to nearly 13 cases per 100,000 inhabitants in 2000s. Over the last few years, several studies have shown increasing EoE figures, which have been placing the frequency of the disease in up to 1 in 2000 people. These figures, however, have become obsolete following the recent publication in recent months of two extensive epidemiological studies that provide new data on the epidemiology of the disease in Europe and in the United States.

The first of these works by Ángel Arias & Alfredo J Lucendo analyzes the epidemiology of the disease in a central region of Spain. The authors updated a previous research carried out up to 2011. For adult patients with EoE they have now documented a mean annual incidence of 9.1 new cases per 100,000 inhabitants, exceeding the overall incidence rate of 7.2 that was provided by a meta-analysis summarizing studies carried out between 2008 and 2015. The incidence rate documented here for EoE currently equals that reported for Crohn’s disease in European Countries,including Spain, which ranges between 8.6 and 9.9 new cases per100,000/year.

The authors updated a previous research carried out up to 2011. For adult patients with EoE they have now documented a mean annual incidence of 9.1 new cases per 100,000 inhabitants, exceeding the overall incidence rate of 7.2 that was provided by a meta-analysis summarizing studies carried out between 2008 and 2015. The incidence rate documented here for EoE currently equals that reported for Crohn’s disease in European Countries,including Spain, which ranges between 8.6 and 9.9 new cases per100,000/year.

The prevalence of EoE among adult patients was 111.9 cases per 100,000 inhabitants, thus constituting the highest prevalence for EoE reportedso far.

As for children, an average incidence rate of 10.6 new EoE casesper 100,000 inhabitants, provides evidence that there is an increase,which has grown progressively over time, in the appearance of new EoE cases for this age group also. Population studies carriedout before 2008 showed an overall annual incidence for paediatric EoE of 3.3 cases per 100,000 inhabitants, which increased to 7.3 for studies published after this date. Consequently, the prevalence of EoE in children rapidly increased in central Spain during the years covered by this research, up to a period cumulative prevalence of 105.1 cases per 100,000 inhabitants, and peaking at 111.9 cases per 100,000inhabitants in 2017. The prevalence was almost three times higherin boys than in girls.

The second study by Jacob Robson and collaborators from the Division of Pediatric Gastroenterology at the University of Utah, Salt Lake City, UT ology and Nutrition, Department of Pediatrics, University of Utah, Salt Lake City, Utah present pediatric EoE incidence and prevalence data in Utah spanning a 5-year period. Cases were identified with a search of pathology records for all patients <18 years old who had an endoscopic esophageal biopsy obtained during the study window. Medical records were reviewed to confirm the patient was living in Utah at the time of diagnosis and special attention was paid to ensure the patient did not have evidence of an EoE diagnosis prior to the study period.

Excluding patients not living in Utah at the time of endoscopy and those who did not meet criteria for incident EoE diagnosis, 1,060 new cases of pediatric EoE were identified in Utah over the 5-year study period. The average annual EoE incidence was 24 cases per 100,000 children in Utah over the course of the study. Despite an annual increase of the number of pediatric endoscopies with esophageal biopsy, EoE incidence over the last four years of the study was stable. The prevalence at the end of the 5-year study was 118 cases per 100,000 children, this last figure completely overlaping that provided in Central Spain.

Therefore, two works developed independently by different groups of researchers in Paceintes of very different origin coincide in showing a dramatic increase in the frequency of EoE, which today affects 1 per 850 to 930 patients, regardless of their age.

It should be remembered,however, that the very first cases of EoE were reported less than 4 decades ago and the disease was characterized as a distinct clinico-pathological disorder only in the early 1990s. These population-based studes document a dramatic increase inthe epidemiology of EoE globally over the last few years, to thepoint that it has doubled from the previous estimations provided for Spain and the USA. Considering its chronic nature, the usual recurrence of symptoms and inflammation after treatment withdrawal and the increasingly younger age of affected patients who will suffer from the disease for decades after being diagnosed, the burden of EoE for the national health services will be huge. Efforts to identify risk factors in order to implement preventive strategies to face EoE in future years are urgently needed therefore.

The rising prevalence of the disease cannot be attributed only to the accumulation of cases over time, but also to a continuous and ongoing increase in incidence rates. The reasons behind this increase have not been clarified but their identification is requeried. An increasing generalization in the use of endoscopy for the diagnosis and management of gastroenterological disorders was proposed as an explanation for an increasing frequency of EoE, together with a greater awareness by clinicians that now consider EoE within the differential diagnosis of esophageal dysfunction symptoms. However, recent studies have demonstrated that the increase in new EoE cases outpaces the use of endoscopy with biopsy in the number of new EoE diagnoses during the study period exceeded that of upper endoscopic examations, thus providing additional evidence of a true expansion of the disease in multiple settings over the last decade.

In conclusion, the incidence and prevalence of EoE has increased sharply throughout the last few years in patient of all ages. The present studies report the highestprevalences seen so far for pediatric and adult EoE and provides evidence of the markedly increasing trend in the frequency of EoE documented in several settings. In view of these results, efforts to investigate the causes of EoE and its increasing frequency in order to propose preventive strategies, are urgently needed.

Read the full papers at:

https://www.ncbi.nlm.nih.gov/pubmed/30115573

https://www.ncbi.nlm.nih.gov/pubmed/29935329

Written by Alfredo J Lucendo | Sunday, September 9th, 2018