Epidemiology of eosinophilic esophagitis over three decades in Olmsted County, Minnesota

Abstract

Background & aims: Data on secular trends and outcomes of eosinophilic esophagitis (EE) are scarce. We performed a population-based study to assess the epidemiology and outcomes of EE in Olmsted County, Minnesota, over the last 3 decades.

Methods: All cases of EE diagnosed between 1976 and 2005 were identified using the Rochester Epidemiology Project resources. Esophageal biopsies with any evidence of esophagitis and/or eosinophilic infiltration were reviewed by a single pathologist. Clinical course (treatment, response, and recurrence) was defined using information collected from medical records and prospectively via a telephone questionnaire. Incidence rates per 100,000 person years were directly adjusted for age and sex to the US 2000 population structure.

Results: A total of 78 patients with EE were identified. The incidence of EE increased significantly over the last 3 of the 5-year intervals (from 0.35 [95% confidence interval (CI)], 0-0.87] per 100,000 person-years during 1991-1995 to 9.45 [95% CI, 7.13-11.77] per 100,000 person-years during 2001-2005). The prevalence of EE was 55.0 (95% CI, 42.7-67.2) per 100,000 persons as of January 1, 2006, in Olmsted County, Minnesota. EE was diagnosed more frequently in late summer/fall. The clinical course of patients with EE was characterized by recurrent symptoms (observed in 41% of patients).

Conclusions: The prevalence and incidence of EE is higher than previously reported. The incidence of clinically diagnosed EE increased significantly over the last 3 decades, in parallel with endoscopy volume. Seasonal incidence was greatest in late summer and fall. EE also appears to be a recurrent relapsing disease in a substantial proportion of patients.

Figure 1. Flowsheet describing case identification

MS: Multiple sclerosis, PD: Parkinson’s disease #: Patients with esophagitis mentioned in medical records, radiology (barium x ray) reports $: Patients treated for food bolus impaction in the emergency room successfully with glucagon, not needing endoscopy, those with a mention of this diagnosis in the medical records *: Total number of patients with available biopsies to review (not all patients with an endoscopic diagnosis of reflux esophagitis were routinely biopsied)

Figure 2

Incidence of Eosinophilic Esophagitis in Olmsted County, MN over 6 five year intervals (1976–2005) EE: eosinophilic esophagitis;

Figure 3

Secular trends in endoscopy volume per year and number of EE cases diagnosed per year

Figure 4

Distribution of month of diagnosis of incident cases of EE in Olmsted County from 1976–2005.